From patchwork Thu Sep 3 11:23:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753255 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B5587722 for ; Thu, 3 Sep 2020 11:23:56 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 90FEB2078E for ; Thu, 3 Sep 2020 11:23:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="J+nPTsrf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 90FEB2078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3FAD86E9AA; Thu, 3 Sep 2020 11:23:52 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) by gabe.freedesktop.org (Postfix) with ESMTPS id 830A36E9A8 for ; Thu, 3 Sep 2020 11:23:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132229; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=c+wC7ixkxZtL6B/Ur8An//2LHjZwp8cEzzDSJyc9S+g=; b=J+nPTsrf1k9dtdvD4k6E/TlzZ54UWC93g1s/7AXada02MsHFu5/ILRXkDtLoPtYaYjby7m Qd3C5T4Vj6ER8wpDOw2LeTj6JnOKuEerSCK4VKvQR/IJLAPNxP/Ch6MLLGMn4bZn/7TJ/N 19enBmCwtgJbM+L4xpFy5GHhHzkiq8Q= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-206-02yKD_ADPoeG4RVMWn-kPw-1; Thu, 03 Sep 2020 07:23:47 -0400 X-MC-Unique: 02yKD_ADPoeG4RVMWn-kPw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B6114801AB3; Thu, 3 Sep 2020 11:23:45 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id D88925C1C2; Thu, 3 Sep 2020 11:23:42 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 01/17] ACPI / LPSS: Resume Cherry Trail PWM controller in no-irq phase Date: Thu, 3 Sep 2020 13:23:21 +0200 Message-Id: <20200903112337.4113-2-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , "Rafael J . Wysocki" , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The DSDTs on most Cherry Trail devices have an ugly clutch where the PWM controller gets poked from the _PS0 method of the graphics-card device: Local0 = PSAT /* \_SB_.PCI0.GFX0.PSAT */ If (((Local0 & 0x03) == 0x03)) { PSAT &= 0xFFFFFFFC Local1 = PSAT /* \_SB_.PCI0.GFX0.PSAT */ RSTA = Zero RSTF = Zero RSTA = One RSTF = One PWMB |= 0xC0000000 PWMC = PWMB /* \_SB_.PCI0.GFX0.PWMB */ } Where PSAT is the power-status register of the PWM controller, so if it is in D3 when the GFX0 device's PS0 method runs then it will turn it on and restore the PWM ctrl register value it saved from its PS3 handler. Note not only does it restore it, it ors it with 0xC0000000 turning it on at a time where we may not want it to get turned on at all. The pwm_get call which the i915 driver does to get a reference to the PWM controller, already adds a device-link making the GFX0 device a consumer of the PWM device. So it should already have been resumed when the above AML runs and the AML should thus not do its undesirable poking of the PWM controller register. But the PCI core powers on PCI devices in the no-irq resume phase and thus calls the troublesome PS0 method in the no-irq resume phase. Where as LPSS devices by default are resumed in the early resume phase. This commit sets the resume_from_noirq flag in the bsw_pwm_dev_desc struct, so that Cherry Trail PWM controllers will be resumed in the no-irq phase. Together with the device-link added by the pwm-get this ensures that the PWM controller will be on when the troublesome PS0 method runs, which stops it from poking the PWM controller. Acked-by: Rafael J. Wysocki Signed-off-by: Hans de Goede --- drivers/acpi/acpi_lpss.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c index 5e2bfbcf526f..67892fc0b822 100644 --- a/drivers/acpi/acpi_lpss.c +++ b/drivers/acpi/acpi_lpss.c @@ -257,6 +257,7 @@ static const struct lpss_device_desc bsw_pwm_dev_desc = { .flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY, .prv_offset = 0x800, .setup = bsw_pwm_setup, + .resume_from_noirq = true, }; static const struct lpss_device_desc byt_uart_dev_desc = { From patchwork Thu Sep 3 11:23:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753259 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3D781722 for ; Thu, 3 Sep 2020 11:24:00 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1BDFD2078E for ; Thu, 3 Sep 2020 11:24:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="TWDy0XcE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1BDFD2078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C80B46E9AB; Thu, 3 Sep 2020 11:23:54 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 31B2F6E9AB for ; Thu, 3 Sep 2020 11:23:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132232; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Vz/DPJyK8Z7twHTt1MIA2s6MtCK9x+8KAwAMVF0PM/w=; b=TWDy0XcEiYITqGi36BTQntOhKXEul2fTrYOnPV5Lw/jKuhrpK/13X4GXDdFPPNmRT5hpTm G8zkzRHM84MHkWo+AUqO+7wL3M0Pu898pXPsh9M94NTfMA4R3v5ooE8kJ+vFqDMqBL/lMl d+d8MYCZ7oIMy4kCFeud/sJ1Po9LoGQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-360-8l9JdKUyNkSlwHsJKryuLw-1; Thu, 03 Sep 2020 07:23:50 -0400 X-MC-Unique: 8l9JdKUyNkSlwHsJKryuLw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AE6EC64090; Thu, 3 Sep 2020 11:23:48 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0B2D35C1C2; Thu, 3 Sep 2020 11:23:45 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 02/17] ACPI / LPSS: Save Cherry Trail PWM ctx registers only once (at activation) Date: Thu, 3 Sep 2020 13:23:22 +0200 Message-Id: <20200903112337.4113-3-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , "Rafael J . Wysocki" , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The DSDTs on most Cherry Trail devices have an ugly clutch where the PWM controller gets turned off from the _PS3 method of the graphics-card dev: Method (_PS3, 0, Serialized) // _PS3: Power State 3 { ... PWMB = PWMC /* \_SB_.PCI0.GFX0.PWMC */ PSAT |= 0x03 Local0 = PSAT /* \_SB_.PCI0.GFX0.PSAT */ ... } Where PSAT is the power-status register of the PWM controller. Since the i915 driver will do a pwm_get on the pwm device as it uses it to control the LCD panel backlight, there is a device-link marking the i915 device as a consumer of the pwm device. So that the PWM controller will always be suspended after the i915 driver suspends (which is the right thing to do). This causes the above GFX0 PS3 AML code to run before acpi_lpss.c calls acpi_lpss_save_ctx(). So on these devices the PWM controller will already be off when acpi_lpss_save_ctx() runs. This causes it to read/save all 1-s (0xffffffff) as ctx register values. When these bogus values get restored on resume the PWM controller actually keeps working, since most bits are reserved, but this does set bit 3 of the LPSS General purpose register, which for the PWM controller has the following function: "This bit is re-used to support 32kHz slow mode. Default is 19.2MHz as PWM source clock". This causes the clock of the PWM controller to switch from 19.2MHz to 32KHz, which is a slow-down of a factor 600. Surprisingly enough so far there have been few bug reports about this. This is likely because the i915 driver was hardcoding the PWM frequency to 46 KHz, which divided by 600 would result in a PWM frequency of approx. 78 Hz, which mostly still works fine. There are some bug reports about the LCD backlight flickering after suspend/resume which are likely caused by this issue. But with the upcoming patch-series to finally switch the i915 drivers code for external PWM controllers to use the atomic API and to honor the PWM frequency specified in the video BIOS (VBT), this becomes a much bigger problem. On most cases the VBT specifies either 200 Hz or 20 KHz as PWM frequency, which with the mentioned issue ends up being either 1/3 Hz, where the backlight actually visible blinks on and off every 3s, or in 33 Hz and horrible flickering of the backlight. There are a number of possible solutions to this problem: 1. Make acpi_lpss_save_ctx() run before GFX0._PS3 Pro: Clean solution from pov of not medling with save/restore ctx code Con: As mentioned the current ordering is the right thing to do Con: Requires assymmetry in at what suspend/resume phase we do the save vs restore, requiring more suspend/resume ordering hacks in already convoluted acpi_lpss.c suspend/resume code. 2. Do some sort of save once mode for the LPSS ctx Pro: Reasonably clean Con: Needs a new LPSS flag + code changes to handle the flag 3. Detect we have failed to save the ctx registers and do not restore them Pro: Not PWM specific, might help with issues on other LPSS devices too Con: If we can get away with not restoring the ctx why bother with it at all? 4. Do not save the ctx for CHT PWM controllers Pro: Clean, as simple as dropping a flag? Con: Not so simple as dropping a flag, needs a new flag to ensure that we still do lpss_deassert_reset() on device activation. 5. Make the pwm-lpss code fixup the LPSS-context registers Pro: Keeps acpi_lpss.c code clean Con: Moves knowledge of LPSS-context into the pwm-lpss.c code 1 and 5 both do not seem to be a desirable way forward. 3 and 4 seem ok, but they both assume that restoring the LPSS-context registers is not necessary. I have done a couple of test and those do show that restoring the LPSS-context indeed does not seem to be necessary on devices using s2idle suspend (and successfully reaching S0i3). But I have no hardware to test deep / S3 suspend. So I'm not sure that not restoring the context is safe. That leaves solution 2, which is about as simple / clean as 3 and 4, so this commit fixes the described problem by implementing a new LPSS_SAVE_CTX_ONCE flag and setting that for the CHT PWM controllers. Acked-by: Rafael J. Wysocki Signed-off-by: Hans de Goede --- Changes in v2: - Move #define LPSS_SAVE_CTX_ONCE define to group it with LPSS_SAVE_CTX --- drivers/acpi/acpi_lpss.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c index 67892fc0b822..a8d7d83ac761 100644 --- a/drivers/acpi/acpi_lpss.c +++ b/drivers/acpi/acpi_lpss.c @@ -67,7 +67,15 @@ ACPI_MODULE_NAME("acpi_lpss"); #define LPSS_CLK_DIVIDER BIT(2) #define LPSS_LTR BIT(3) #define LPSS_SAVE_CTX BIT(4) -#define LPSS_NO_D3_DELAY BIT(5) +/* + * For some devices the DSDT AML code for another device turns off the device + * before our suspend handler runs, causing us to read/save all 1-s (0xffffffff) + * as ctx register values. + * Luckily these devices always use the same ctx register values, so we can + * work around this by saving the ctx registers once on activation. + */ +#define LPSS_SAVE_CTX_ONCE BIT(5) +#define LPSS_NO_D3_DELAY BIT(6) struct lpss_private_data; @@ -254,7 +262,7 @@ static const struct lpss_device_desc byt_pwm_dev_desc = { }; static const struct lpss_device_desc bsw_pwm_dev_desc = { - .flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY, + .flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY, .prv_offset = 0x800, .setup = bsw_pwm_setup, .resume_from_noirq = true, @@ -885,9 +893,14 @@ static int acpi_lpss_activate(struct device *dev) * we have to deassert reset line to be sure that ->probe() will * recognize the device. */ - if (pdata->dev_desc->flags & LPSS_SAVE_CTX) + if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE)) lpss_deassert_reset(pdata); +#ifdef CONFIG_PM + if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE) + acpi_lpss_save_ctx(dev, pdata); +#endif + return 0; } @@ -1031,7 +1044,7 @@ static int acpi_lpss_resume(struct device *dev) acpi_lpss_d3_to_d0_delay(pdata); - if (pdata->dev_desc->flags & LPSS_SAVE_CTX) + if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE)) acpi_lpss_restore_ctx(dev, pdata); return 0; From patchwork Thu Sep 3 11:23:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753263 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AF67E14E3 for ; Thu, 3 Sep 2020 11:24:02 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8E1EC2078E for ; Thu, 3 Sep 2020 11:24:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QacDUQnF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E1EC2078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 19EBE6E9B2; 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Thu, 03 Sep 2020 07:23:53 -0400 X-MC-Unique: eqmfdRC_Mci3mD7kcakojw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A1A3D64086; Thu, 3 Sep 2020 11:23:51 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0596D5C1C2; Thu, 3 Sep 2020 11:23:48 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 03/17] pwm: lpss: Fix off by one error in base_unit math in pwm_lpss_prepare() Date: Thu, 3 Sep 2020 13:23:23 +0200 Message-Id: <20200903112337.4113-4-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" According to the data-sheet the way the PWM controller works is that each input clock-cycle the base_unit gets added to a N bit counter and that counter overflowing determines the PWM output frequency. So assuming e.g. a 16 bit counter this means that if base_unit is set to 1, after 65535 input clock-cycles the counter has been increased from 0 to 65535 and it will overflow on the next cycle, so it will overflow after every 65536 clock cycles and thus the calculations done in pwm_lpss_prepare() should use 65536 and not 65535. This commit fixes this. Note this also aligns the calculations in pwm_lpss_prepare() with those in pwm_lpss_get_state(). Note this effectively reverts commit 684309e5043e ("pwm: lpss: Avoid potential overflow of base_unit"). The next patch in this series really fixes the potential overflow of the base_unit value. Fixes: 684309e5043e ("pwm: lpss: Avoid potential overflow of base_unit") Reviewed-by: Andy Shevchenko Acked-by: Uwe Kleine-König Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- Changes in v3: - Add Fixes tag - Add Reviewed-by: Andy Shevchenko tag --- drivers/pwm/pwm-lpss.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c index 9d965ffe66d1..43b1fc634af1 100644 --- a/drivers/pwm/pwm-lpss.c +++ b/drivers/pwm/pwm-lpss.c @@ -93,7 +93,7 @@ static void pwm_lpss_prepare(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm, * The equation is: * base_unit = round(base_unit_range * freq / c) */ - base_unit_range = BIT(lpwm->info->base_unit_bits) - 1; + base_unit_range = BIT(lpwm->info->base_unit_bits); freq *= base_unit_range; base_unit = DIV_ROUND_CLOSEST_ULL(freq, c); @@ -104,8 +104,8 @@ static void pwm_lpss_prepare(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm, orig_ctrl = ctrl = pwm_lpss_read(pwm); ctrl &= ~PWM_ON_TIME_DIV_MASK; - ctrl &= ~(base_unit_range << PWM_BASE_UNIT_SHIFT); - base_unit &= base_unit_range; + ctrl &= ~((base_unit_range - 1) << PWM_BASE_UNIT_SHIFT); + base_unit &= (base_unit_range - 1); ctrl |= (u32) base_unit << PWM_BASE_UNIT_SHIFT; ctrl |= on_time_div; From patchwork Thu Sep 3 11:23:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753267 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ED9BD166C for ; Thu, 3 Sep 2020 11:24:04 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CC4882078E for ; Thu, 3 Sep 2020 11:24:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UzfIJ8Yg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC4882078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C817F6E9B3; Thu, 3 Sep 2020 11:24:00 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2B0646E9B3 for ; Thu, 3 Sep 2020 11:23:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132238; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZukzWkoKOICgMwClnkSHfjft9LoCEglKBEzHtiqOOV4=; b=UzfIJ8Yg+GGJlz4Dm57uaPWRb+8+9tblrRDJ0Tz9XZaF7ncJ0IkcgbLep46S0ji3FuZMzV u0Qe4BxJd56eQoW0nL7NI+QGgu7jsdLsLRwoKBPcht62Ykyt7RagHmkkWTmOgsKjJ0LW4G 017e2v/ePqDJBvW/5zDn2xza7PS9/eQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-10-pdpVvNiWPduzJMNpzU_yqA-1; Thu, 03 Sep 2020 07:23:56 -0400 X-MC-Unique: pdpVvNiWPduzJMNpzU_yqA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A117C10ABDB8; Thu, 3 Sep 2020 11:23:54 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id EB0625C1C2; Thu, 3 Sep 2020 11:23:51 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 04/17] pwm: lpss: Add range limit check for the base_unit register value Date: Thu, 3 Sep 2020 13:23:24 +0200 Message-Id: <20200903112337.4113-5-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" When the user requests a high enough period ns value, then the calculations in pwm_lpss_prepare() might result in a base_unit value of 0. But according to the data-sheet the way the PWM controller works is that each input clock-cycle the base_unit gets added to a N bit counter and that counter overflowing determines the PWM output frequency. Adding 0 to the counter is a no-op. The data-sheet even explicitly states that writing 0 to the base_unit bits will result in the PWM outputting a continuous 0 signal. When the user requestes a low enough period ns value, then the calculations in pwm_lpss_prepare() might result in a base_unit value which is bigger then base_unit_range - 1. Currently the codes for this deals with this by applying a mask: base_unit &= (base_unit_range - 1); But this means that we let the value overflow the range, we throw away the higher bits and store whatever value is left in the lower bits into the register leading to a random output frequency, rather then clamping the output frequency to the highest frequency which the hardware can do. This commit fixes both issues by clamping the base_unit value to be between 1 and (base_unit_range - 1). Fixes: 684309e5043e ("pwm: lpss: Avoid potential overflow of base_unit") Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- Changes in v5: - Use clamp_val(... instead of clam_t(unsigned long long, ... Changes in v3: - Change upper limit of clamp to (base_unit_range - 1) - Add Fixes tag --- drivers/pwm/pwm-lpss.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c index 43b1fc634af1..da9bc3d10104 100644 --- a/drivers/pwm/pwm-lpss.c +++ b/drivers/pwm/pwm-lpss.c @@ -97,6 +97,8 @@ static void pwm_lpss_prepare(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm, freq *= base_unit_range; base_unit = DIV_ROUND_CLOSEST_ULL(freq, c); + /* base_unit must not be 0 and we also want to avoid overflowing it */ + base_unit = clamp_val(base_unit, 1, base_unit_range - 1); on_time_div = 255ULL * duty_ns; do_div(on_time_div, period_ns); @@ -105,7 +107,6 @@ static void pwm_lpss_prepare(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm, orig_ctrl = ctrl = pwm_lpss_read(pwm); ctrl &= ~PWM_ON_TIME_DIV_MASK; ctrl &= ~((base_unit_range - 1) << PWM_BASE_UNIT_SHIFT); - base_unit &= (base_unit_range - 1); ctrl |= (u32) base_unit << PWM_BASE_UNIT_SHIFT; ctrl |= on_time_div; From patchwork Thu Sep 3 11:23:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753271 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2F6C7722 for ; Thu, 3 Sep 2020 11:24:07 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0DE5A2078E for ; Thu, 3 Sep 2020 11:24:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bdGBE9IV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0DE5A2078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AF7026E9B4; Thu, 3 Sep 2020 11:24:04 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 495256E9B0 for ; Thu, 3 Sep 2020 11:24:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132242; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=oeojNYihj1/4GnBYNf4T6ofPGFiKE3ZSQ6kb3lrJ21A=; b=bdGBE9IVxYD0nrHks7bi3l+ij1iiGM0+iQOvgY51ezrfst1lkCN9HaSfKgvxqazXeUv5+X AVo/HWA+51ZbWNIat78i/x911Pv3I/MmWl+JuI7RBIVg7qSxMBTsXdUxGCAUs4UgsxwIUE jOgbVzkFb4CyeBqwyowaIXIO7HsoT/Y= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-286-7d56g-MINIe_IRrt3oiCgQ-1; Thu, 03 Sep 2020 07:24:00 -0400 X-MC-Unique: 7d56g-MINIe_IRrt3oiCgQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9A9FD1008552; Thu, 3 Sep 2020 11:23:58 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id F202A5C1C2; Thu, 3 Sep 2020 11:23:54 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 05/17] pwm: lpss: Add pwm_lpss_prepare_enable() helper Date: Thu, 3 Sep 2020 13:23:25 +0200 Message-Id: <20200903112337.4113-6-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" In the not-enabled -> enabled path pwm_lpss_apply() needs to get a runtime-pm reference; and then on any errors it needs to release it again. This leads to somewhat hard to read code. This commit introduces a new pwm_lpss_prepare_enable() helper and moves all the steps necessary for the not-enabled -> enabled transition there, so that we can error check the entire transition in a single place and only have one pm_runtime_put() on failure call site. While working on this I noticed that the enabled -> enabled (update settings) path was quite similar, so I've added an enable parameter to the new pwm_lpss_prepare_enable() helper, which allows using it in that path too. Suggested-by: Andy Shevchenko Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- drivers/pwm/pwm-lpss.c | 45 ++++++++++++++++++++++++------------------ 1 file changed, 26 insertions(+), 19 deletions(-) diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c index da9bc3d10104..8a136ba2a583 100644 --- a/drivers/pwm/pwm-lpss.c +++ b/drivers/pwm/pwm-lpss.c @@ -122,41 +122,48 @@ static inline void pwm_lpss_cond_enable(struct pwm_device *pwm, bool cond) pwm_lpss_write(pwm, pwm_lpss_read(pwm) | PWM_ENABLE); } +static int pwm_lpss_prepare_enable(struct pwm_lpss_chip *lpwm, + struct pwm_device *pwm, + const struct pwm_state *state, + bool enable) +{ + int ret; + + ret = pwm_lpss_is_updating(pwm); + if (ret) + return ret; + + pwm_lpss_prepare(lpwm, pwm, state->duty_cycle, state->period); + pwm_lpss_cond_enable(pwm, enable && lpwm->info->bypass == false); + ret = pwm_lpss_wait_for_update(pwm); + if (ret) + return ret; + + pwm_lpss_cond_enable(pwm, enable && lpwm->info->bypass == true); + return 0; +} + static int pwm_lpss_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { struct pwm_lpss_chip *lpwm = to_lpwm(chip); - int ret; + int ret = 0; if (state->enabled) { if (!pwm_is_enabled(pwm)) { pm_runtime_get_sync(chip->dev); - ret = pwm_lpss_is_updating(pwm); - if (ret) { - pm_runtime_put(chip->dev); - return ret; - } - pwm_lpss_prepare(lpwm, pwm, state->duty_cycle, state->period); - pwm_lpss_cond_enable(pwm, lpwm->info->bypass == false); - ret = pwm_lpss_wait_for_update(pwm); - if (ret) { + ret = pwm_lpss_prepare_enable(lpwm, pwm, state, true); + if (ret) pm_runtime_put(chip->dev); - return ret; - } - pwm_lpss_cond_enable(pwm, lpwm->info->bypass == true); } else { - ret = pwm_lpss_is_updating(pwm); - if (ret) - return ret; - pwm_lpss_prepare(lpwm, pwm, state->duty_cycle, state->period); - return pwm_lpss_wait_for_update(pwm); + ret = pwm_lpss_prepare_enable(lpwm, pwm, state, false); } } else if (pwm_is_enabled(pwm)) { pwm_lpss_write(pwm, pwm_lpss_read(pwm) & ~PWM_ENABLE); pm_runtime_put(chip->dev); } - return 0; + return ret; } static void pwm_lpss_get_state(struct pwm_chip *chip, struct pwm_device *pwm, From patchwork Thu Sep 3 11:23:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753273 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CDBF214E3 for ; Thu, 3 Sep 2020 11:24:09 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AC79E2087C for ; Thu, 3 Sep 2020 11:24:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="V0DrcurM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AC79E2087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C9A0D6E9B5; Thu, 3 Sep 2020 11:24:08 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-1.mimecast.com [205.139.110.61]) by gabe.freedesktop.org (Postfix) with ESMTPS id 283D86E9B6 for ; Thu, 3 Sep 2020 11:24:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132247; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rcsh1Zuxbjaphp45a6ku70Y44sKjR/XPz2zgB+NaLdU=; b=V0DrcurMy/TXNUxCvJLs5G7p4hb9YZrcf9m0KT5id2JdTTTltWP5UkBp8+tvOmzHPVqTHD iQlCh8zIJ1bc9ndZjgGhx7jzcczyJvtFp4j4lr3Gcn8bceeFjw9gDHpr6SFRxVddvnJP4n lyiJyCHl5OwfAf4+Bk5OVW/sxEryOks= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-352-37hU4JLoNKeg_puT9la2AQ-1; Thu, 03 Sep 2020 07:24:03 -0400 X-MC-Unique: 37hU4JLoNKeg_puT9la2AQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 945008015DB; Thu, 3 Sep 2020 11:24:01 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id E11B55C1C2; Thu, 3 Sep 2020 11:23:58 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 06/17] pwm: lpss: Make pwm_lpss_apply() not rely on existing hardware state Date: Thu, 3 Sep 2020 13:23:26 +0200 Message-Id: <20200903112337.4113-7-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Before this commit pwm_lpss_apply() was assuming 2 pre-conditions were met by the existing hardware state: 1. That the base-unit and on-time-div read back from the control register are those actually in use, so that it can skip setting the update bit if the read-back value matches the desired values. 2. That the controller is enabled when the cached pwm_state.enabled says that the controller is enabled. As the long history of fixes for subtle (often suspend/resume) lpss-pwm issues shows, these assumptions are not necessary always true. 1. Specifically is not true on some (*) Cherry Trail devices with a nasty GFX0._PS3 method which: a. saves the ctrl reg value. b. sets the base-unit to 0 and writes the update bit to apply/commit c. restores the original ctrl value without setting the update bit, so that the 0 base-unit value is still in use. 2. Assumption 2. currently is true, but only because of the code which saves/restores the state on suspend/resume. By convention restoring the PWM state should be done by the PWM consumer and the presence of this code in the pmw-lpss driver is a bug. Therefor the save/restore code will be dropped in the next patch in this series, after which this assumption also is no longer true. This commit changes the pwm_lpss_apply() to not make any assumptions about the state the hardware is in. Instead it makes pwm_lpss_apply() always fully program the PWM controller, making it much less fragile. *) Seen on the Acer One 10 S1003, Lenovo Ideapad Miix 310 and 320 models and various Medion models. Acked-by: Thierry Reding Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- Changes in v10: - Fixup some wording / mistakes in the commit message Changes in v9: - This is a new patch in v9 of this series --- drivers/pwm/pwm-lpss.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c index 8a136ba2a583..9c5c7217c9b6 100644 --- a/drivers/pwm/pwm-lpss.c +++ b/drivers/pwm/pwm-lpss.c @@ -85,7 +85,7 @@ static void pwm_lpss_prepare(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm, unsigned long long on_time_div; unsigned long c = lpwm->info->clk_rate, base_unit_range; unsigned long long base_unit, freq = NSEC_PER_SEC; - u32 orig_ctrl, ctrl; + u32 ctrl; do_div(freq, period_ns); @@ -104,16 +104,14 @@ static void pwm_lpss_prepare(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm, do_div(on_time_div, period_ns); on_time_div = 255ULL - on_time_div; - orig_ctrl = ctrl = pwm_lpss_read(pwm); + ctrl = pwm_lpss_read(pwm); ctrl &= ~PWM_ON_TIME_DIV_MASK; ctrl &= ~((base_unit_range - 1) << PWM_BASE_UNIT_SHIFT); ctrl |= (u32) base_unit << PWM_BASE_UNIT_SHIFT; ctrl |= on_time_div; - if (orig_ctrl != ctrl) { - pwm_lpss_write(pwm, ctrl); - pwm_lpss_write(pwm, ctrl | PWM_SW_UPDATE); - } + pwm_lpss_write(pwm, ctrl); + pwm_lpss_write(pwm, ctrl | PWM_SW_UPDATE); } static inline void pwm_lpss_cond_enable(struct pwm_device *pwm, bool cond) @@ -124,8 +122,7 @@ static inline void pwm_lpss_cond_enable(struct pwm_device *pwm, bool cond) static int pwm_lpss_prepare_enable(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm, - const struct pwm_state *state, - bool enable) + const struct pwm_state *state) { int ret; @@ -134,12 +131,12 @@ static int pwm_lpss_prepare_enable(struct pwm_lpss_chip *lpwm, return ret; pwm_lpss_prepare(lpwm, pwm, state->duty_cycle, state->period); - pwm_lpss_cond_enable(pwm, enable && lpwm->info->bypass == false); + pwm_lpss_cond_enable(pwm, lpwm->info->bypass == false); ret = pwm_lpss_wait_for_update(pwm); if (ret) return ret; - pwm_lpss_cond_enable(pwm, enable && lpwm->info->bypass == true); + pwm_lpss_cond_enable(pwm, lpwm->info->bypass == true); return 0; } @@ -152,11 +149,11 @@ static int pwm_lpss_apply(struct pwm_chip *chip, struct pwm_device *pwm, if (state->enabled) { if (!pwm_is_enabled(pwm)) { pm_runtime_get_sync(chip->dev); - ret = pwm_lpss_prepare_enable(lpwm, pwm, state, true); + ret = pwm_lpss_prepare_enable(lpwm, pwm, state); if (ret) pm_runtime_put(chip->dev); } else { - ret = pwm_lpss_prepare_enable(lpwm, pwm, state, false); + ret = pwm_lpss_prepare_enable(lpwm, pwm, state); } } else if (pwm_is_enabled(pwm)) { pwm_lpss_write(pwm, pwm_lpss_read(pwm) & ~PWM_ENABLE); From patchwork Thu Sep 3 11:23:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753279 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 38D97166C for ; 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Thu, 3 Sep 2020 11:24:06 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id DC2CC5C1C2; Thu, 3 Sep 2020 11:24:01 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 07/17] pwm: lpss: Remove suspend/resume handlers Date: Thu, 3 Sep 2020 13:23:27 +0200 Message-Id: <20200903112337.4113-8-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" PWM controller drivers should not restore the PWM state on resume. The convention is that PWM consumers do this by calling pwm_apply_state(), so that it can be done at the exact moment when the consumer needs the state to be stored, avoiding e.g. backlight flickering. The only in kernel consumers of the pwm-lpss code, the i915 driver and the pwm-class sysfs interface code both correctly restore the state on resume, so there is no need to do this in the pwm-lpss code. More-over the removed resume handler is buggy, since it blindly restores the ctrl-register contents without setting the update bit, which is necessary to get the controller to actually use/apply the restored base-unit and on-time-div values. Acked-by: Thierry Reding Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- Changes in v9: - This is a new patch in v9 of this series --- drivers/pwm/pwm-lpss-platform.c | 1 - drivers/pwm/pwm-lpss.c | 24 ------------------------ drivers/pwm/pwm-lpss.h | 3 --- 3 files changed, 28 deletions(-) diff --git a/drivers/pwm/pwm-lpss-platform.c b/drivers/pwm/pwm-lpss-platform.c index 48f34d20aecd..c6502cf7a7af 100644 --- a/drivers/pwm/pwm-lpss-platform.c +++ b/drivers/pwm/pwm-lpss-platform.c @@ -89,7 +89,6 @@ static int pwm_lpss_prepare(struct device *dev) static const struct dev_pm_ops pwm_lpss_platform_pm_ops = { .prepare = pwm_lpss_prepare, - SET_SYSTEM_SLEEP_PM_OPS(pwm_lpss_suspend, pwm_lpss_resume) }; static const struct acpi_device_id pwm_lpss_acpi_match[] = { diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c index 9c5c7217c9b6..3444c56b4bed 100644 --- a/drivers/pwm/pwm-lpss.c +++ b/drivers/pwm/pwm-lpss.c @@ -260,30 +260,6 @@ int pwm_lpss_remove(struct pwm_lpss_chip *lpwm) } EXPORT_SYMBOL_GPL(pwm_lpss_remove); -int pwm_lpss_suspend(struct device *dev) -{ - struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev); - int i; - - for (i = 0; i < lpwm->info->npwm; i++) - lpwm->saved_ctrl[i] = readl(lpwm->regs + i * PWM_SIZE + PWM); - - return 0; -} -EXPORT_SYMBOL_GPL(pwm_lpss_suspend); - -int pwm_lpss_resume(struct device *dev) -{ - struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev); - int i; - - for (i = 0; i < lpwm->info->npwm; i++) - writel(lpwm->saved_ctrl[i], lpwm->regs + i * PWM_SIZE + PWM); - - return 0; -} -EXPORT_SYMBOL_GPL(pwm_lpss_resume); - MODULE_DESCRIPTION("PWM driver for Intel LPSS"); MODULE_AUTHOR("Mika Westerberg "); MODULE_LICENSE("GPL v2"); diff --git a/drivers/pwm/pwm-lpss.h b/drivers/pwm/pwm-lpss.h index 7909fa12fca2..70db7e389d66 100644 --- a/drivers/pwm/pwm-lpss.h +++ b/drivers/pwm/pwm-lpss.h @@ -19,7 +19,6 @@ struct pwm_lpss_chip { struct pwm_chip chip; void __iomem *regs; const struct pwm_lpss_boardinfo *info; - u32 saved_ctrl[MAX_PWMS]; }; struct pwm_lpss_boardinfo { @@ -37,7 +36,5 @@ struct pwm_lpss_boardinfo { struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev, struct resource *r, const struct pwm_lpss_boardinfo *info); int pwm_lpss_remove(struct pwm_lpss_chip *lpwm); -int pwm_lpss_suspend(struct device *dev); -int pwm_lpss_resume(struct device *dev); #endif /* __PWM_LPSS_H */ From patchwork Thu Sep 3 11:23:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753283 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D30B314E3 for ; Thu, 3 Sep 2020 11:24:19 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B1F872083B for ; Thu, 3 Sep 2020 11:24:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="EOAzVj6h" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B1F872083B Authentication-Results: mail.kernel.org; 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Thu, 03 Sep 2020 07:24:14 -0400 X-MC-Unique: B0vmSOdDOKOmHE0IMh7tmQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 69478801AB3; Thu, 3 Sep 2020 11:24:12 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id A12915C1C2; Thu, 3 Sep 2020 11:24:06 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 08/17] pwm: crc: Fix period / duty_cycle times being off by a factor of 256 Date: Thu, 3 Sep 2020 13:23:28 +0200 Message-Id: <20200903112337.4113-9-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" While looking into adding atomic-pwm support to the pwm-crc driver I noticed something odd, there is a PWM_BASE_CLK define of 6 MHz and there is a clock-divider which divides this with a value between 1-128, and there are 256 duty-cycle steps. The pwm-crc code before this commit assumed that a clock-divider setting of 1 means that the PWM output is running at 6 MHZ, if that is true, where do these 256 duty-cycle steps come from? This would require an internal frequency of 256 * 6 MHz = 1.5 GHz, that seems unlikely for a PMIC which is using a silicon process optimized for power-switching transistors. It is way more likely that there is an 8 bit counter for the duty cycle which acts as an extra fixed divider wrt the PWM output frequency. The main user of the pwm-crc driver is the i915 GPU driver which uses it for backlight control. Lets compare the PWM register values set by the video-BIOS (the GOP), assuming the extra fixed divider is present versus the PWM frequency specified in the Video-BIOS-Tables: Device: PWM Hz set by BIOS PWM Hz specified in VBT Asus T100TA 200 200 Asus T100HA 200 200 Lenovo Miix 2 8 23437 20000 Toshiba WT8-A 23437 20000 So as we can see if we assume the extra division by 256 then the register values set by the GOP are an exact match for the VBT values, where as otherwise the values would be of by a factor of 256. This commit fixes the period / duty_cycle calculations to take the extra division by 256 into account. Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- Changes in v3: - Use NSEC_PER_USEC instead of adding a new (non-sensical) NSEC_PER_MHZ define --- drivers/pwm/pwm-crc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c index 272eeb071147..c056eb9b858c 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -21,8 +21,8 @@ #define PWM_MAX_LEVEL 0xFF -#define PWM_BASE_CLK 6000000 /* 6 MHz */ -#define PWM_MAX_PERIOD_NS 21333 /* 46.875KHz */ +#define PWM_BASE_CLK_MHZ 6 /* 6 MHz */ +#define PWM_MAX_PERIOD_NS 5461333 /* 183 Hz */ /** * struct crystalcove_pwm - Crystal Cove PWM controller @@ -72,7 +72,7 @@ static int crc_pwm_config(struct pwm_chip *c, struct pwm_device *pwm, /* changing the clk divisor, need to disable fisrt */ crc_pwm_disable(c, pwm); - clk_div = PWM_BASE_CLK * period_ns / NSEC_PER_SEC; + clk_div = PWM_BASE_CLK_MHZ * period_ns / (256 * NSEC_PER_USEC); regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, clk_div | PWM_OUTPUT_ENABLE); From patchwork Thu Sep 3 11:23:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753287 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 85F71722 for ; Thu, 3 Sep 2020 11:24:23 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5FCDE2087C for ; Thu, 3 Sep 2020 11:24:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="iJFo0pUw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5FCDE2087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6972A6E9C0; Thu, 3 Sep 2020 11:24:22 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 134BF6E9C0 for ; Thu, 3 Sep 2020 11:24:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132260; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Y73Fo+LL3s7ZWkvjroKn4rnnokL4shRdg8EOZEgl13g=; b=iJFo0pUwq+PF4nvYWdcZW01y0up5OOOQdzsln/2HBSqWeUbfjnxuawMJBBQ0w29mSKpRTw /DbMz722W5LR1f0sl86uPybvdTGvBxEHSSmDbUHlVPbUbRrN/loXCQr5QKeUGfrDOW/89e Wqo2YCImoGQZ7Wqe9IDfV6zivP4wSxM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-555-52q8BwU6PuGWcy1tNvY-QA-1; Thu, 03 Sep 2020 07:24:18 -0400 X-MC-Unique: 52q8BwU6PuGWcy1tNvY-QA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C2E5464087; Thu, 3 Sep 2020 11:24:16 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id B6B505C1C2; Thu, 3 Sep 2020 11:24:12 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 09/17] pwm: crc: Fix off-by-one error in the clock-divider calculations Date: Thu, 3 Sep 2020 13:23:29 +0200 Message-Id: <20200903112337.4113-10-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The CRC PWM controller has a clock-divider which divides the clock with a value between 1-128. But as can seen from the PWM_DIV_CLK_xxx defines, this range maps to a register value of 0-127. So after calculating the clock-divider we must subtract 1 to get the register value, unless the requested frequency was so high that the calculation has already resulted in a (rounded) divider value of 0. Note that before this fix, setting a period of PWM_MAX_PERIOD_NS which corresponds to the max. divider value of 128 could have resulted in a bug where the code would use 128 as divider-register value which would have resulted in an actual divider value of 0 (and the enable bit being set). A rounding error stopped this bug from actually happen. This same rounding error means that after the subtraction of 1 it is impossible to set the divider to 128. Also bump PWM_MAX_PERIOD_NS by 1 ns to allow setting a divider of 128 (register-value 127). Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- Changes in v3: - Introduce crc_pwm_calc_clk_div() here instead of later in the patch-set to reduce the amount of churn in the patch-set a bit --- drivers/pwm/pwm-crc.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c index c056eb9b858c..44ec7d5b63e1 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -22,7 +22,7 @@ #define PWM_MAX_LEVEL 0xFF #define PWM_BASE_CLK_MHZ 6 /* 6 MHz */ -#define PWM_MAX_PERIOD_NS 5461333 /* 183 Hz */ +#define PWM_MAX_PERIOD_NS 5461334 /* 183 Hz */ /** * struct crystalcove_pwm - Crystal Cove PWM controller @@ -39,6 +39,18 @@ static inline struct crystalcove_pwm *to_crc_pwm(struct pwm_chip *pc) return container_of(pc, struct crystalcove_pwm, chip); } +static int crc_pwm_calc_clk_div(int period_ns) +{ + int clk_div; + + clk_div = PWM_BASE_CLK_MHZ * period_ns / (256 * NSEC_PER_USEC); + /* clk_div 1 - 128, maps to register values 0-127 */ + if (clk_div > 0) + clk_div--; + + return clk_div; +} + static int crc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm) { struct crystalcove_pwm *crc_pwm = to_crc_pwm(c); @@ -68,11 +80,10 @@ static int crc_pwm_config(struct pwm_chip *c, struct pwm_device *pwm, } if (pwm_get_period(pwm) != period_ns) { - int clk_div; + int clk_div = crc_pwm_calc_clk_div(period_ns); /* changing the clk divisor, need to disable fisrt */ crc_pwm_disable(c, pwm); - clk_div = PWM_BASE_CLK_MHZ * period_ns / (256 * NSEC_PER_USEC); regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, clk_div | PWM_OUTPUT_ENABLE); From patchwork Thu Sep 3 11:23:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753291 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 25CFD14E3 for ; Thu, 3 Sep 2020 11:24:29 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0435B2087C for ; Thu, 3 Sep 2020 11:24:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HokFkIAA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0435B2087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E9B456E9C2; Thu, 3 Sep 2020 11:24:27 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id ECD9A6E9B8 for ; Thu, 3 Sep 2020 11:24:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132265; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ssNgCUXpAKBFoEiowMJpHnd/L+IbBFe8IIgVfV3vAFg=; b=HokFkIAAQFewi9cuTuxVgh1srA1eZx3AUMRyWWqqReok+8jPCI1MJ0sOOKT3p9flQ1XpTd sRqaORV6mMe/RoUibnYpDrRizBKIkfTy9O2rQ00Rx6IliAi4HV+0h85q+A5Nvdd9nkomdZ MBu/jcDY9TgA6gn9x58cOrJSFpSy6qs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-282-vbgng-ZqM0OwQkfEcHtloQ-1; Thu, 03 Sep 2020 07:24:23 -0400 X-MC-Unique: vbgng-ZqM0OwQkfEcHtloQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A7BCD100855C; Thu, 3 Sep 2020 11:24:21 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 18EE05C1C2; Thu, 3 Sep 2020 11:24:16 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 10/17] pwm: crc: Fix period changes not having any effect Date: Thu, 3 Sep 2020 13:23:30 +0200 Message-Id: <20200903112337.4113-11-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The pwm-crc code is using 2 different enable bits: 1. bit 7 of the PWM0_CLK_DIV (PWM_OUTPUT_ENABLE) 2. bit 0 of the BACKLIGHT_EN register The BACKLIGHT_EN register at address 0x51 really controls a separate output-only GPIO which is earmarked to be used as output connected to the backlight-enable pin for LCD panels, this GPO is part of the PMIC's "Display Panel Control Block." . This pin should probably be moved over to a GPIO provider driver (and consumers modified accordingly), but that is something for an(other) patch. Enabling / disabling the actual PWM output is controlled by the PWM_OUTPUT_ENABLE bit of the PWM0_CLK_DIV register. As the comment in the old code already indicates we must disable the PWM before we can change the clock divider. But the crc_pwm_disable() and crc_pwm_enable() calls the old code make for this only change the BACKLIGHT_EN register; and the value of that register does not matter for changing the period / the divider. What does matter is that the PWM_OUTPUT_ENABLE bit must be cleared before a new value can be written. This commit modifies crc_pwm_config() to clear PWM_OUTPUT_ENABLE instead when changing the period, so that period changes actually work. Note this fix will cause a significant behavior change on some devices using the CRC PWM output to drive their backlight. Before the PWM would always run with the output frequency configured by the BIOS at boot, now the period time specified by the i915 driver will actually be honored. Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- drivers/pwm/pwm-crc.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c index 44ec7d5b63e1..81232da0c767 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -82,14 +82,11 @@ static int crc_pwm_config(struct pwm_chip *c, struct pwm_device *pwm, if (pwm_get_period(pwm) != period_ns) { int clk_div = crc_pwm_calc_clk_div(period_ns); - /* changing the clk divisor, need to disable fisrt */ - crc_pwm_disable(c, pwm); + /* changing the clk divisor, clear PWM_OUTPUT_ENABLE first */ + regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, 0); regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, clk_div | PWM_OUTPUT_ENABLE); - - /* enable back */ - crc_pwm_enable(c, pwm); } /* change the pwm duty cycle */ From patchwork Thu Sep 3 11:23:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753293 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3D633722 for ; Thu, 3 Sep 2020 11:24:33 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1BF382087C for ; Thu, 3 Sep 2020 11:24:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="VvdU/Bf3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1BF382087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 363686E9BB; Thu, 3 Sep 2020 11:24:32 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 428E16E9C1 for ; Thu, 3 Sep 2020 11:24:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132270; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bls/UFMf0L0kdioky5wX0QpmXgpNAMyX15B1clsViAI=; b=VvdU/Bf3kDE3Lo2mxjLvuWGvMahPsY59GraHacOhS0jgIVGnIaH1wZLU/MocFv+5OzABJe 6ej8mcBkxa1dll48PCJRyS1MPp4npiNAtnfNtr/zs8puvBCYcG8LmfJots6K9cvgS5GMWf J6fRu1aJWeyPWFgb0gH3lgNg/9acPY4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-157-Gb-25KYKNryeOE-1n4DYcg-1; Thu, 03 Sep 2020 07:24:28 -0400 X-MC-Unique: Gb-25KYKNryeOE-1n4DYcg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 80F84640A7; Thu, 3 Sep 2020 11:24:26 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 014FC5C1C2; Thu, 3 Sep 2020 11:24:21 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 11/17] pwm: crc: Enable/disable PWM output on enable/disable Date: Thu, 3 Sep 2020 13:23:31 +0200 Message-Id: <20200903112337.4113-12-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The pwm-crc code is using 2 different enable bits: 1. bit 7 of the PWM0_CLK_DIV (PWM_OUTPUT_ENABLE) 2. bit 0 of the BACKLIGHT_EN register So far we've kept the PWM_OUTPUT_ENABLE bit set when disabling the PWM, this commit makes crc_pwm_disable() clear it on disable and makes crc_pwm_enable() set it again on re-enable. Acked-by: Uwe Kleine-König Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- Changes in v3: - Remove paragraph about tri-stating the output from the commit message, we don't have a datasheet so this was just an unfounded guess --- drivers/pwm/pwm-crc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c index 81232da0c767..b72008c9b072 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -54,7 +54,9 @@ static int crc_pwm_calc_clk_div(int period_ns) static int crc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm) { struct crystalcove_pwm *crc_pwm = to_crc_pwm(c); + int div = crc_pwm_calc_clk_div(pwm_get_period(pwm)); + regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div | PWM_OUTPUT_ENABLE); regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1); return 0; @@ -63,8 +65,10 @@ static int crc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm) static void crc_pwm_disable(struct pwm_chip *c, struct pwm_device *pwm) { struct crystalcove_pwm *crc_pwm = to_crc_pwm(c); + int div = crc_pwm_calc_clk_div(pwm_get_period(pwm)); regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 0); + regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div); } static int crc_pwm_config(struct pwm_chip *c, struct pwm_device *pwm, From patchwork Thu Sep 3 11:23:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753297 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5A34F14E3 for ; Thu, 3 Sep 2020 11:24:38 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 38BD5208B3 for ; Thu, 3 Sep 2020 11:24:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="h/vjbK9l" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 38BD5208B3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 737E16E9C3; Thu, 3 Sep 2020 11:24:37 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-1.mimecast.com [207.211.31.81]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4A19C6E9C4 for ; Thu, 3 Sep 2020 11:24:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132275; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ssaDmZ3q4kks75jcoGrHn3rdUGB2JCDdcC8N/xAd3GA=; b=h/vjbK9lgV7uZGg7XS8IJohQAwdESppmqdciGrbxYoRn3tfKjI60AHkWEID844t65jHM+L i2jdTOrIVXIgnVhSOd5/JM3fgn6Fh0qHw/Skmy2OC11RP6wjPjPgWIJF7vkCcok9KAzZ4P gpRJBV0Y9eQQORKde4FDR37p17zZRQI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-109-Ih1gWwOKPkmaZkg1k-xeCg-1; Thu, 03 Sep 2020 07:24:33 -0400 X-MC-Unique: Ih1gWwOKPkmaZkg1k-xeCg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E5D006409F; Thu, 3 Sep 2020 11:24:31 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id CBCE45C1C2; Thu, 3 Sep 2020 11:24:26 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 12/17] pwm: crc: Implement apply() method to support the new atomic PWM API Date: Thu, 3 Sep 2020 13:23:32 +0200 Message-Id: <20200903112337.4113-13-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Replace the enable, disable and config pwm_ops with an apply op, to support the new atomic PWM API. Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- Changes in v6: - Rebase on 5.9-rc1 - Use do_div when calculating level because pwm_state.period and .duty_cycle are now u64 Changes in v3: - Keep crc_pwm_calc_clk_div() helper to avoid needless churn --- drivers/pwm/pwm-crc.c | 89 ++++++++++++++++++++++++++----------------- 1 file changed, 54 insertions(+), 35 deletions(-) diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c index b72008c9b072..27dc30882424 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -51,59 +51,78 @@ static int crc_pwm_calc_clk_div(int period_ns) return clk_div; } -static int crc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm) +static int crc_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) { - struct crystalcove_pwm *crc_pwm = to_crc_pwm(c); - int div = crc_pwm_calc_clk_div(pwm_get_period(pwm)); + struct crystalcove_pwm *crc_pwm = to_crc_pwm(chip); + struct device *dev = crc_pwm->chip.dev; + int err; - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div | PWM_OUTPUT_ENABLE); - regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1); + if (state->period > PWM_MAX_PERIOD_NS) { + dev_err(dev, "un-supported period_ns\n"); + return -EINVAL; + } - return 0; -} + if (state->polarity != PWM_POLARITY_NORMAL) + return -EOPNOTSUPP; -static void crc_pwm_disable(struct pwm_chip *c, struct pwm_device *pwm) -{ - struct crystalcove_pwm *crc_pwm = to_crc_pwm(c); - int div = crc_pwm_calc_clk_div(pwm_get_period(pwm)); + if (pwm_is_enabled(pwm) && !state->enabled) { + err = regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 0); + if (err) { + dev_err(dev, "Error writing BACKLIGHT_EN %d\n", err); + return err; + } + } - regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 0); - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div); -} + if (pwm_get_duty_cycle(pwm) != state->duty_cycle || + pwm_get_period(pwm) != state->period) { + u64 level = state->duty_cycle * PWM_MAX_LEVEL; -static int crc_pwm_config(struct pwm_chip *c, struct pwm_device *pwm, - int duty_ns, int period_ns) -{ - struct crystalcove_pwm *crc_pwm = to_crc_pwm(c); - struct device *dev = crc_pwm->chip.dev; - int level; + do_div(level, state->period); - if (period_ns > PWM_MAX_PERIOD_NS) { - dev_err(dev, "un-supported period_ns\n"); - return -EINVAL; + err = regmap_write(crc_pwm->regmap, PWM0_DUTY_CYCLE, level); + if (err) { + dev_err(dev, "Error writing PWM0_DUTY_CYCLE %d\n", err); + return err; + } } - if (pwm_get_period(pwm) != period_ns) { - int clk_div = crc_pwm_calc_clk_div(period_ns); - + if (pwm_is_enabled(pwm) && state->enabled && + pwm_get_period(pwm) != state->period) { /* changing the clk divisor, clear PWM_OUTPUT_ENABLE first */ - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, 0); + err = regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, 0); + if (err) { + dev_err(dev, "Error writing PWM0_CLK_DIV %d\n", err); + return err; + } + } - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, - clk_div | PWM_OUTPUT_ENABLE); + if (pwm_get_period(pwm) != state->period || + pwm_is_enabled(pwm) != state->enabled) { + int clk_div = crc_pwm_calc_clk_div(state->period); + int pwm_output_enable = state->enabled ? PWM_OUTPUT_ENABLE : 0; + + err = regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, + clk_div | pwm_output_enable); + if (err) { + dev_err(dev, "Error writing PWM0_CLK_DIV %d\n", err); + return err; + } } - /* change the pwm duty cycle */ - level = duty_ns * PWM_MAX_LEVEL / period_ns; - regmap_write(crc_pwm->regmap, PWM0_DUTY_CYCLE, level); + if (!pwm_is_enabled(pwm) && state->enabled) { + err = regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1); + if (err) { + dev_err(dev, "Error writing BACKLIGHT_EN %d\n", err); + return err; + } + } return 0; } static const struct pwm_ops crc_pwm_ops = { - .config = crc_pwm_config, - .enable = crc_pwm_enable, - .disable = crc_pwm_disable, + .apply = crc_pwm_apply, }; static int crystalcove_pwm_probe(struct platform_device *pdev) From patchwork Thu Sep 3 11:23:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753301 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4F9AD722 for ; Thu, 3 Sep 2020 11:24:45 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2DFEC2087C for ; Thu, 3 Sep 2020 11:24:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OYQFpV4u" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2DFEC2087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6150D6E9C5; Thu, 3 Sep 2020 11:24:44 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) by gabe.freedesktop.org (Postfix) with ESMTPS id 872FD6E9C5 for ; Thu, 3 Sep 2020 11:24:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132282; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BihA1BpHNAPbZmr7utm+7lcBoH9ReI2g/yHAfDzPOZk=; b=OYQFpV4uJalEEn2AIyB5Gh9cWlkZFZYA3z1SclVSjAeyWD34QzQ8L90vch0l4B8KsYZ7Oz onsl7sb07KdRFBXVgGy9V3tv3ikPEwRYKmBVHl70qLXtMNaTd7zP98mimFrmZu7RWSFC+o jBmklVYktPaHwFbMlzDP90z3yWWRYu4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-86-EHjOs5jPN_eBJa0VFXdbgA-1; Thu, 03 Sep 2020 07:24:40 -0400 X-MC-Unique: EHjOs5jPN_eBJa0VFXdbgA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D353910ABDD1; Thu, 3 Sep 2020 11:24:35 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3B8FF5C1C2; Thu, 3 Sep 2020 11:24:32 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 13/17] pwm: crc: Implement get_state() method Date: Thu, 3 Sep 2020 13:23:33 +0200 Message-Id: <20200903112337.4113-14-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Implement the pwm_ops.get_state() method to complete the support for the new atomic PWM API. Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede --- Changes in v6: - Rebase on 5.9-rc1 - Use DIV_ROUND_UP_ULL because pwm_state.period and .duty_cycle are now u64 Changes in v5: - Fix an indentation issue Changes in v4: - Use DIV_ROUND_UP when calculating the period and duty_cycle from the controller's register values Changes in v3: - Add Andy's Reviewed-by tag - Remove extra whitespace to align some code after assignments (requested by Uwe Kleine-König) --- drivers/pwm/pwm-crc.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c index 27dc30882424..ecfdfac0c2d9 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -121,8 +121,39 @@ static int crc_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } +static void crc_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct crystalcove_pwm *crc_pwm = to_crc_pwm(chip); + struct device *dev = crc_pwm->chip.dev; + unsigned int clk_div, clk_div_reg, duty_cycle_reg; + int error; + + error = regmap_read(crc_pwm->regmap, PWM0_CLK_DIV, &clk_div_reg); + if (error) { + dev_err(dev, "Error reading PWM0_CLK_DIV %d\n", error); + return; + } + + error = regmap_read(crc_pwm->regmap, PWM0_DUTY_CYCLE, &duty_cycle_reg); + if (error) { + dev_err(dev, "Error reading PWM0_DUTY_CYCLE %d\n", error); + return; + } + + clk_div = (clk_div_reg & ~PWM_OUTPUT_ENABLE) + 1; + + state->period = + DIV_ROUND_UP(clk_div * NSEC_PER_USEC * 256, PWM_BASE_CLK_MHZ); + state->duty_cycle = + DIV_ROUND_UP_ULL(duty_cycle_reg * state->period, PWM_MAX_LEVEL); + state->polarity = PWM_POLARITY_NORMAL; + state->enabled = !!(clk_div_reg & PWM_OUTPUT_ENABLE); +} + static const struct pwm_ops crc_pwm_ops = { .apply = crc_pwm_apply, + .get_state = crc_pwm_get_state, }; static int crystalcove_pwm_probe(struct platform_device *pdev) From patchwork Thu Sep 3 11:23:34 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753309 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A362B722 for ; Thu, 3 Sep 2020 11:24:52 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 820AC2078E for ; Thu, 3 Sep 2020 11:24:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QGFBICdp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 820AC2078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AB6D96E9C9; Thu, 3 Sep 2020 11:24:50 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) by gabe.freedesktop.org (Postfix) with ESMTPS id D8EF56E9C9 for ; Thu, 3 Sep 2020 11:24:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132287; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1wMXBHDyyQ6t98T6xFtSD2movAwUy8KekR8cCyDYfqQ=; b=QGFBICdp4wjlJm2QScMyUCpHKzqJeiyV/trAwi45qgGpS0TiJuOkZgVWpEWzDYLp+wFK0d Na3xsIinHRGjOLzIyDKcNq7/zkEA9vXC618eFyQHumswoiAuYuIrxgazLpsjwbUdc8ZVVV Atz325j5huZbqHsul1i6rdrdsjIQrt4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-442-KJlaSW5qPvSXYSHkIJdPeQ-1; Thu, 03 Sep 2020 07:24:43 -0400 X-MC-Unique: KJlaSW5qPvSXYSHkIJdPeQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 24E1910ABDBC; Thu, 3 Sep 2020 11:24:41 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 260115C1C2; Thu, 3 Sep 2020 11:24:36 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 14/17] drm/i915: panel: Add get_vbt_pwm_freq() helper Date: Thu, 3 Sep 2020 13:23:34 +0200 Message-Id: <20200903112337.4113-15-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, Jani Nikula , intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Factor the code which checks and drm_dbg_kms-s the VBT PWM frequency out of get_backlight_max_vbt(). This is a preparation patch for honering the VBT PWM frequency for devices which use an external PWM controller (devices using pwm_setup_backlight()). Acked-by: Jani Nikula Signed-off-by: Hans de Goede --- drivers/gpu/drm/i915/display/intel_panel.c | 27 ++++++++++++++-------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c index 4072d7062efd..df7472a3b9f8 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.c +++ b/drivers/gpu/drm/i915/display/intel_panel.c @@ -1543,18 +1543,9 @@ static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul); } -static u32 get_backlight_max_vbt(struct intel_connector *connector) +static u16 get_vbt_pwm_freq(struct drm_i915_private *dev_priv) { - struct drm_i915_private *dev_priv = to_i915(connector->base.dev); - struct intel_panel *panel = &connector->panel; u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz; - u32 pwm; - - if (!panel->backlight.hz_to_pwm) { - drm_dbg_kms(&dev_priv->drm, - "backlight frequency conversion not supported\n"); - return 0; - } if (pwm_freq_hz) { drm_dbg_kms(&dev_priv->drm, @@ -1567,6 +1558,22 @@ static u32 get_backlight_max_vbt(struct intel_connector *connector) pwm_freq_hz); } + return pwm_freq_hz; +} + +static u32 get_backlight_max_vbt(struct intel_connector *connector) +{ + struct drm_i915_private *dev_priv = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + u16 pwm_freq_hz = get_vbt_pwm_freq(dev_priv); + u32 pwm; + + if (!panel->backlight.hz_to_pwm) { + drm_dbg_kms(&dev_priv->drm, + "backlight frequency conversion not supported\n"); + return 0; + } + pwm = panel->backlight.hz_to_pwm(connector, pwm_freq_hz); if (!pwm) { drm_dbg_kms(&dev_priv->drm, From patchwork Thu Sep 3 11:23:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753311 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 225FB722 for ; Thu, 3 Sep 2020 11:24:54 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 012B42078E for ; Thu, 3 Sep 2020 11:24:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="aFXCXxGE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 012B42078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 17DD16E9CC; Thu, 3 Sep 2020 11:24:51 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-2.mimecast.com [207.211.31.81]) by gabe.freedesktop.org (Postfix) with ESMTPS id 326996E9C9 for ; Thu, 3 Sep 2020 11:24:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132288; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=sVjx4EGfhRBDZlJyfOCPuAVbuYnQnae4/qIYiLWMT1M=; b=aFXCXxGERXAhGtCk/A9SMeZXftLvtz5tHPGg17nVK3RbtPiphcxOGsOj+CE1sS4G2fPrRP cya8NqKSta3nJDfQeEMOhA/TDexSr96OgaJIGm4kbHyqWKz5K03GtSBd3aBfAMqLR85g5/ 5xcBf7a/tyHwU4wTBO4Xy5zDQtchp80= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-547-3A717rmQMKq6aUtx-lCz8Q-1; Thu, 03 Sep 2020 07:24:46 -0400 X-MC-Unique: 3A717rmQMKq6aUtx-lCz8Q-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A7922101964D; Thu, 3 Sep 2020 11:24:44 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7300F5C1C2; Thu, 3 Sep 2020 11:24:41 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 15/17] drm/i915: panel: Honor the VBT PWM frequency for devs with an external PWM controller Date: Thu, 3 Sep 2020 13:23:35 +0200 Message-Id: <20200903112337.4113-16-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, Jani Nikula , intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" So far for devices using an external PWM controller (devices using pwm_setup_backlight()), we have been hardcoding the period-time passed to pwm_config() to 21333 ns. I suspect this was done because many VBTs set the PWM frequency to 200 which corresponds to a period-time of 5000000 ns, which greatly exceeds the PWM_MAX_PERIOD_NS define in the Crystal Cove PMIC PWM driver, which used to be 21333. This PWM_MAX_PERIOD_NS define was actually based on a bug in the PWM driver where its period and duty-cycle times where off by a factor of 256. Due to this bug the hardcoded CRC_PMIC_PWM_PERIOD_NS value of 21333 would result in the PWM driver using its divider of 128, which would result in a PWM output frequency of 6000000 Hz / 256 / 128 = 183 Hz. So actually pretty close to the default VBT value of 200 Hz. Now that this bug in the pwm-crc driver is fixed, we can actually use the VBT defined frequency. This is important because: a) With the pwm-crc driver fixed it will now translate the hardcoded CRC_PMIC_PWM_PERIOD_NS value of 21333 ns / 46 Khz to a PWM output frequency of 23 KHz (the max it can do). b) The pwm-lpss driver used on many models has always honored the 21333 ns / 46 Khz request Some panels do not like such high output frequencies. E.g. on a Terra Pad 1061 tablet, using the LPSS PWM controller, the backlight would go from off to max, when changing the sysfs backlight brightness value from 90-100%, anything under aprox. 90% would turn the backlight fully off. Honoring the VBT specified PWM frequency will also hopefully fix the various bug reports which we have received about users perceiving the backlight to flicker after a suspend/resume cycle. Acked-by: Jani Nikula Signed-off-by: Hans de Goede --- .../drm/i915/display/intel_display_types.h | 1 + drivers/gpu/drm/i915/display/intel_panel.c | 19 +++++++++++-------- 2 files changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index e8f809161c75..7171e7c8d928 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -223,6 +223,7 @@ struct intel_panel { bool util_pin_active_low; /* bxt+ */ u8 controller; /* bxt+ only */ struct pwm_device *pwm; + int pwm_period_ns; /* DPCD backlight */ u8 pwmgen_bit_count; diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c index df7472a3b9f8..5a13089d2fc0 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.c +++ b/drivers/gpu/drm/i915/display/intel_panel.c @@ -40,8 +40,6 @@ #include "intel_dsi_dcs_backlight.h" #include "intel_panel.h" -#define CRC_PMIC_PWM_PERIOD_NS 21333 - void intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode, struct drm_display_mode *adjusted_mode) @@ -597,7 +595,7 @@ static u32 pwm_get_backlight(struct intel_connector *connector) int duty_ns; duty_ns = pwm_get_duty_cycle(panel->backlight.pwm); - return DIV_ROUND_UP(duty_ns * 100, CRC_PMIC_PWM_PERIOD_NS); + return DIV_ROUND_UP(duty_ns * 100, panel->backlight.pwm_period_ns); } static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level) @@ -671,9 +669,10 @@ static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 static void pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level) { struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel; - int duty_ns = DIV_ROUND_UP(level * CRC_PMIC_PWM_PERIOD_NS, 100); + int duty_ns = DIV_ROUND_UP(level * panel->backlight.pwm_period_ns, 100); - pwm_config(panel->backlight.pwm, duty_ns, CRC_PMIC_PWM_PERIOD_NS); + pwm_config(panel->backlight.pwm, duty_ns, + panel->backlight.pwm_period_ns); } static void @@ -1917,6 +1916,9 @@ static int pwm_setup_backlight(struct intel_connector *connector, return -ENODEV; } + panel->backlight.pwm_period_ns = NSEC_PER_SEC / + get_vbt_pwm_freq(dev_priv); + /* * FIXME: pwm_apply_args() should be removed when switching to * the atomic PWM API. @@ -1926,9 +1928,10 @@ static int pwm_setup_backlight(struct intel_connector *connector, panel->backlight.min = 0; /* 0% */ panel->backlight.max = 100; /* 100% */ level = intel_panel_compute_brightness(connector, 100); - ns = DIV_ROUND_UP(level * CRC_PMIC_PWM_PERIOD_NS, 100); + ns = DIV_ROUND_UP(level * panel->backlight.pwm_period_ns, 100); - retval = pwm_config(panel->backlight.pwm, ns, CRC_PMIC_PWM_PERIOD_NS); + retval = pwm_config(panel->backlight.pwm, ns, + panel->backlight.pwm_period_ns); if (retval < 0) { drm_err(&dev_priv->drm, "Failed to configure the pwm chip\n"); pwm_put(panel->backlight.pwm); @@ -1937,7 +1940,7 @@ static int pwm_setup_backlight(struct intel_connector *connector, } level = DIV_ROUND_UP_ULL(pwm_get_duty_cycle(panel->backlight.pwm) * 100, - CRC_PMIC_PWM_PERIOD_NS); + panel->backlight.pwm_period_ns); panel->backlight.level = intel_panel_compute_brightness(connector, level); panel->backlight.enabled = panel->backlight.level != 0; From patchwork Thu Sep 3 11:23:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753313 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ADCC914E3 for ; Thu, 3 Sep 2020 11:24:55 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8CA422087C for ; Thu, 3 Sep 2020 11:24:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="D24uhsdj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8CA422087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 85A2E6E9C8; Thu, 3 Sep 2020 11:24:54 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-1.mimecast.com [205.139.110.61]) by gabe.freedesktop.org (Postfix) with ESMTPS id 096D46E9D0 for ; Thu, 3 Sep 2020 11:24:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132292; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yBZnW0uEhs9/IogdfbWxz1WbKxUqUn2zepvhTOAX9YU=; b=D24uhsdjnE0xuPVjXcx/GzIdDkcFWWr85yj2Bk/iV/BLomdPUyNvO0ksyP0Osdw3SRTmlG 1s4HrZM9UdKEEmnyS+1h2gsSEZ/ntH4+ZRLvqgtyy2jtiDGEkwCSIfs7WV7sdM38eL/6DR dib9Iis8fnYciafETVC/z3yZ0NuSqk8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-448-qa9iJHyvMaC3FbI8_BYOBQ-1; Thu, 03 Sep 2020 07:24:50 -0400 X-MC-Unique: qa9iJHyvMaC3FbI8_BYOBQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5430A640C2; Thu, 3 Sep 2020 11:24:48 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id EE8BD5C1C2; Thu, 3 Sep 2020 11:24:44 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 16/17] drm/i915: panel: Honor the VBT PWM min setting for devs with an external PWM controller Date: Thu, 3 Sep 2020 13:23:36 +0200 Message-Id: <20200903112337.4113-17-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, Jani Nikula , intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" So far for devices using an external PWM controller (devices using pwm_setup_backlight()), we have been hardcoding the minimum allowed PWM level to 0. But several of these devices specify a non 0 minimum setting in their VBT. Change pwm_setup_backlight() to use get_backlight_min_vbt() to get the minimum level. Acked-by: Jani Nikula Signed-off-by: Hans de Goede --- drivers/gpu/drm/i915/display/intel_panel.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c index 5a13089d2fc0..2b27f9b07403 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.c +++ b/drivers/gpu/drm/i915/display/intel_panel.c @@ -1925,8 +1925,8 @@ static int pwm_setup_backlight(struct intel_connector *connector, */ pwm_apply_args(panel->backlight.pwm); - panel->backlight.min = 0; /* 0% */ panel->backlight.max = 100; /* 100% */ + panel->backlight.min = get_backlight_min_vbt(connector); level = intel_panel_compute_brightness(connector, 100); ns = DIV_ROUND_UP(level * panel->backlight.pwm_period_ns, 100); @@ -1941,8 +1941,9 @@ static int pwm_setup_backlight(struct intel_connector *connector, level = DIV_ROUND_UP_ULL(pwm_get_duty_cycle(panel->backlight.pwm) * 100, panel->backlight.pwm_period_ns); - panel->backlight.level = - intel_panel_compute_brightness(connector, level); + level = intel_panel_compute_brightness(connector, level); + panel->backlight.level = clamp(level, panel->backlight.min, + panel->backlight.max); panel->backlight.enabled = panel->backlight.level != 0; drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n", From patchwork Thu Sep 3 11:23:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11753317 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1AD64722 for ; Thu, 3 Sep 2020 11:24:59 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EDA402087C for ; Thu, 3 Sep 2020 11:24:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ImWESKNK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EDA402087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1B9256E9CE; Thu, 3 Sep 2020 11:24:58 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 774CB6E9CF for ; Thu, 3 Sep 2020 11:24:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599132295; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SbhNPGZV282TeLHWXKEb2sWXfyYtHG5yCs5qSe3JTB8=; b=ImWESKNKjSRaN1Rx3TQSWxMDHJvRIgTCRfm/dC38vV/x2JCW1acUiFFijuUMvoqNCA5LIE Y4zniizOF1xZVFVUo1GcG0hza+fcQ4coeKZ098JYeR87tnxDFVGTTBiBr7NiaHDF6RJl/N YBtjnr9beMEtpBjFkPLu247iA8b9g3o= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-176-0OIiQSk_P6mbrFv32cBcPg-1; Thu, 03 Sep 2020 07:24:54 -0400 X-MC-Unique: 0OIiQSk_P6mbrFv32cBcPg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BF93610ABDBF; Thu, 3 Sep 2020 11:24:51 +0000 (UTC) Received: from x1.localdomain (ovpn-113-3.ams2.redhat.com [10.36.113.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9B84B5C1C2; Thu, 3 Sep 2020 11:24:48 +0000 (UTC) From: Hans de Goede To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , "Rafael J . Wysocki" , Len Brown Subject: [PATCH v10 17/17] drm/i915: panel: Use atomic PWM API for devs with an external PWM controller Date: Thu, 3 Sep 2020 13:23:37 +0200 Message-Id: <20200903112337.4113-18-hdegoede@redhat.com> In-Reply-To: <20200903112337.4113-1-hdegoede@redhat.com> References: <20200903112337.4113-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-acpi@vger.kernel.org, Jani Nikula , intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , Andy Shevchenko , Mika Westerberg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Now that the PWM drivers which we use have been converted to the atomic PWM API, we can move the i915 panel code over to using the atomic PWM API. The removes a long standing FIXME and this removes a flicker where the backlight brightness would jump to 100% when i915 loads even if using the fastset path. Note that this commit also simplifies pwm_disable_backlight(), by dropping the intel_panel_actually_set_backlight(..., 0) call. This call sets the PWM to 0% duty-cycle. I believe that this call was only present as a workaround for a bug in the pwm-crc.c driver where it failed to clear the PWM_OUTPUT_ENABLE bit. This is fixed by an earlier patch in this series. After the dropping of this workaround, the usleep call, which seems unnecessary to begin with, has no useful effect anymore, so drop that too. Acked-by: Jani Nikula Signed-off-by: Hans de Goede --- Changes in v7: - Fix a u64 divide leading to undefined reference to `__udivdi3' errors on 32 bit platforms by casting the divisor to an unsigned long Changes in v6: - Drop the pwm_get_period() check in pwm_setup(), it is now longer needed now that we use pwm_get_relative_duty_cycle() Changes in v4: - Add a note to the commit message about the dropping of the intel_panel_actually_set_backlight() and usleep() calls from pwm_disable_backlight() - Use the pwm_set/get_relative_duty_cycle() helpers instead of using DIY code for this --- .../drm/i915/display/intel_display_types.h | 3 +- drivers/gpu/drm/i915/display/intel_panel.c | 70 ++++++++----------- 2 files changed, 33 insertions(+), 40 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index 7171e7c8d928..e3ebe7c313ba 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -28,6 +28,7 @@ #include #include +#include #include #include @@ -223,7 +224,7 @@ struct intel_panel { bool util_pin_active_low; /* bxt+ */ u8 controller; /* bxt+ only */ struct pwm_device *pwm; - int pwm_period_ns; + struct pwm_state pwm_state; /* DPCD backlight */ u8 pwmgen_bit_count; diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c index 2b27f9b07403..2eb1a3a93df1 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.c +++ b/drivers/gpu/drm/i915/display/intel_panel.c @@ -592,10 +592,10 @@ static u32 bxt_get_backlight(struct intel_connector *connector) static u32 pwm_get_backlight(struct intel_connector *connector) { struct intel_panel *panel = &connector->panel; - int duty_ns; + struct pwm_state state; - duty_ns = pwm_get_duty_cycle(panel->backlight.pwm); - return DIV_ROUND_UP(duty_ns * 100, panel->backlight.pwm_period_ns); + pwm_get_state(panel->backlight.pwm, &state); + return pwm_get_relative_duty_cycle(&state, 100); } static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level) @@ -669,10 +669,9 @@ static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 static void pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level) { struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel; - int duty_ns = DIV_ROUND_UP(level * panel->backlight.pwm_period_ns, 100); - pwm_config(panel->backlight.pwm, duty_ns, - panel->backlight.pwm_period_ns); + pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100); + pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state); } static void @@ -841,10 +840,8 @@ static void pwm_disable_backlight(const struct drm_connector_state *old_conn_sta struct intel_connector *connector = to_intel_connector(old_conn_state->connector); struct intel_panel *panel = &connector->panel; - /* Disable the backlight */ - intel_panel_actually_set_backlight(old_conn_state, 0); - usleep_range(2000, 3000); - pwm_disable(panel->backlight.pwm); + panel->backlight.pwm_state.enabled = false; + pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state); } void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state) @@ -1176,9 +1173,12 @@ static void pwm_enable_backlight(const struct intel_crtc_state *crtc_state, { struct intel_connector *connector = to_intel_connector(conn_state->connector); struct intel_panel *panel = &connector->panel; + int level = panel->backlight.level; - pwm_enable(panel->backlight.pwm); - intel_panel_actually_set_backlight(conn_state, panel->backlight.level); + level = intel_panel_compute_brightness(connector, level); + pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100); + panel->backlight.pwm_state.enabled = true; + pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state); } static void __intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state, @@ -1897,8 +1897,7 @@ static int pwm_setup_backlight(struct intel_connector *connector, struct drm_i915_private *dev_priv = to_i915(dev); struct intel_panel *panel = &connector->panel; const char *desc; - u32 level, ns; - int retval; + u32 level; /* Get the right PWM chip for DSI backlight according to VBT */ if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) { @@ -1916,35 +1915,28 @@ static int pwm_setup_backlight(struct intel_connector *connector, return -ENODEV; } - panel->backlight.pwm_period_ns = NSEC_PER_SEC / - get_vbt_pwm_freq(dev_priv); - - /* - * FIXME: pwm_apply_args() should be removed when switching to - * the atomic PWM API. - */ - pwm_apply_args(panel->backlight.pwm); - panel->backlight.max = 100; /* 100% */ panel->backlight.min = get_backlight_min_vbt(connector); - level = intel_panel_compute_brightness(connector, 100); - ns = DIV_ROUND_UP(level * panel->backlight.pwm_period_ns, 100); - retval = pwm_config(panel->backlight.pwm, ns, - panel->backlight.pwm_period_ns); - if (retval < 0) { - drm_err(&dev_priv->drm, "Failed to configure the pwm chip\n"); - pwm_put(panel->backlight.pwm); - panel->backlight.pwm = NULL; - return retval; - } + if (pwm_is_enabled(panel->backlight.pwm)) { + /* PWM is already enabled, use existing settings */ + pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state); - level = DIV_ROUND_UP_ULL(pwm_get_duty_cycle(panel->backlight.pwm) * 100, - panel->backlight.pwm_period_ns); - level = intel_panel_compute_brightness(connector, level); - panel->backlight.level = clamp(level, panel->backlight.min, - panel->backlight.max); - panel->backlight.enabled = panel->backlight.level != 0; + level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state, + 100); + level = intel_panel_compute_brightness(connector, level); + panel->backlight.level = clamp(level, panel->backlight.min, + panel->backlight.max); + panel->backlight.enabled = true; + + drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n", + NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period, + get_vbt_pwm_freq(dev_priv), level); + } else { + /* Set period from VBT frequency, leave other settings at 0. */ + panel->backlight.pwm_state.period = + NSEC_PER_SEC / get_vbt_pwm_freq(dev_priv); + } drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n", desc);