From patchwork Fri Jul 17 13:37:38 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: 11670263 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 35E9560D for ; Fri, 17 Jul 2020 13:38:09 +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 118A520734 for ; Fri, 17 Jul 2020 13:38:09 +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="HKRDxY/q" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 118A520734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 80EBB6EDAE; Fri, 17 Jul 2020 13:38:08 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 7AF766EDAE for ; Fri, 17 Jul 2020 13:38:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993086; 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=z+DukUbGqLxIgEoyTxsZKRT/VqP8R1wZu1OA1t1Nqi4=; b=HKRDxY/q0vfXMUBVatGE8QR6LvtJZ//uKeVVsrdmJE8XOPe91SzSjxuKG1fS1gDE5pRkR5 YLJv7i/F83fsFA5VAQipWawLodXs0DtNSR0aOXxZg5hX/17JEo4o7fwSmr7CaWs5CqRYFR JdD0Nujci/2IPg3p/CXhkjN7rMNpQgQ= 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-308-snlYMAJ9NMCDqGh5qry_AA-1; Fri, 17 Jul 2020 09:38:02 -0400 X-MC-Unique: snlYMAJ9NMCDqGh5qry_AA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5FC1F107ACCA; Fri, 17 Jul 2020 13:38:00 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id ACD668FA2F; Fri, 17 Jul 2020 13:37:57 +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 Date: Fri, 17 Jul 2020 15:37:38 +0200 Message-Id: <20200717133753.127282-2-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 01/16] ACPI / LPSS: Resume Cherry Trail PWM controller in no-irq phase X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 Fri Jul 17 13:37:39 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: 11670271 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 083A860D for ; Fri, 17 Jul 2020 13:38:15 +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 DA8CC20734 for ; Fri, 17 Jul 2020 13:38:14 +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="aUiwmYdG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DA8CC20734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 55A126EDB2; Fri, 17 Jul 2020 13:38:12 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 486216EDB2 for ; Fri, 17 Jul 2020 13:38:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993089; 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=/gPKngnvzgVzWE2GaHMS110IozFoJNDcY5HjY8Agmjc=; b=aUiwmYdGhXaLgdFR5j4z6L+YslirH692XClyfPnIOlkssppOSKDFPbnkfhzUdMKgQOENLS ZwSlucrw1H5Ayt7MdE9INI+zBccFvhDKjHxxUTA7SZhZSHjH6SoHl3CyvzdVoJa1QSMUEZ rhJbmnMXqnJTr7exsuspVxXPUwJXKHk= 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-EKWMcNZRPi62oV5PNavWTA-1; Fri, 17 Jul 2020 09:38:05 -0400 X-MC-Unique: EKWMcNZRPi62oV5PNavWTA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6633D800470; Fri, 17 Jul 2020 13:38:03 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id A524A8FA27; Fri, 17 Jul 2020 13:38:00 +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 Date: Fri, 17 Jul 2020 15:37:39 +0200 Message-Id: <20200717133753.127282-3-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 02/16] ACPI / LPSS: Save Cherry Trail PWM ctx registers only once (at activation) X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 Fri Jul 17 13:37:40 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: 11670283 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 91F0C60D for ; Fri, 17 Jul 2020 13:38:22 +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 7007820734 for ; Fri, 17 Jul 2020 13:38:22 +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="BdPJGF4e" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7007820734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0992C6EDB4; 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Fri, 17 Jul 2020 09:38:10 -0400 X-MC-Unique: KnMtlRA_M86BSXcFzF_l5g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C06C21DE3; Fri, 17 Jul 2020 13:38:08 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id AA1B98FA27; Fri, 17 Jul 2020 13:38:03 +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 Date: Fri, 17 Jul 2020 15:37:40 +0200 Message-Id: <20200717133753.127282-4-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 03/16] pwm: lpss: Fix off by one error in base_unit math in pwm_lpss_prepare() X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 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 Fri Jul 17 13:37:41 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: 11670279 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 0952F618 for ; Fri, 17 Jul 2020 13:38:20 +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 DB5E720759 for ; Fri, 17 Jul 2020 13:38:19 +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="R1K9rn44" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB5E720759 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 617026EC75; Fri, 17 Jul 2020 13:38:18 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 C39276EC75 for ; Fri, 17 Jul 2020 13:38:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993095; 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=ZEia1iyS9kteob5Qg+X0J7hYEECiauY8z/tZvjJdw/Q=; b=R1K9rn44VQ6GV8KprHq4nkhgqfHhZuEYz+8g395ZzByL3wtmKH/zQzRR8hmEVLWhOSwI1V IyNZQ2drMYN5j4/eD/CyoB+apN55IgOfZlpVdOaDu8MwUhqcU2FvszN96U7n27qfN/47TG ZL/6sKVAUPAvB8Ua2fVeSPLRr9KlFz4= 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-455-XJlNu97EPXWIujvfHaO0Vw-1; Fri, 17 Jul 2020 09:38:13 -0400 X-MC-Unique: XJlNu97EPXWIujvfHaO0Vw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D7432E92C; Fri, 17 Jul 2020 13:38:11 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 120CC8FA27; Fri, 17 Jul 2020 13:38:08 +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 Date: Fri, 17 Jul 2020 15:37:41 +0200 Message-Id: <20200717133753.127282-5-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 04/16] pwm: lpss: Add range limit check for the base_unit register value X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 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 Fri Jul 17 13:37:42 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: 11670287 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 67EB013B6 for ; Fri, 17 Jul 2020 13:38:23 +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 462ED20734 for ; Fri, 17 Jul 2020 13:38:23 +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="P0s6XoKg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 462ED20734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CF6F26EDB9; Fri, 17 Jul 2020 13:38:21 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9BC4B6EDBE for ; Fri, 17 Jul 2020 13:38:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993098; 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=Q3yN+sz0BulP+W2UATYOsntq/Bj7oAK8zYvKmp5zmWw=; b=P0s6XoKg4sgaDBBvHt5FZ6CSRAW1dS06hdWVUs6cQxsMztpSYCrB3TomrILIRc8GevAZF/ 1HMwOvQokwLUSjM1b/9UYh/QLiT/Z3Lf4kxlmBh6C0o2cfIg1FaYs0WrrxPtyLa3elDk0Y 9+3Zq9uxy7Xop2S3TuPKrSGwO+48g5o= 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-467-NqJ7eKLIP7WaqJ0y0AWh2A-1; Fri, 17 Jul 2020 09:38:17 -0400 X-MC-Unique: NqJ7eKLIP7WaqJ0y0AWh2A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C0FF68EB969; Fri, 17 Jul 2020 13:38:14 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2833B8FA27; Fri, 17 Jul 2020 13:38:12 +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 Date: Fri, 17 Jul 2020 15:37:42 +0200 Message-Id: <20200717133753.127282-6-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 05/16] pwm: lpss: Add pwm_lpss_prepare_enable() helper X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- 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 Fri Jul 17 13:37:43 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: 11670295 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 30966618 for ; Fri, 17 Jul 2020 13:38:30 +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 0EFB320734 for ; Fri, 17 Jul 2020 13:38:30 +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="LRSnwWzA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0EFB320734 Authentication-Results: mail.kernel.org; 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Fri, 17 Jul 2020 09:38:20 -0400 X-MC-Unique: 8IJKdJJ7OjiUxxNK2RRIfA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 79C198EB965; Fri, 17 Jul 2020 13:38:18 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 120D68FA27; Fri, 17 Jul 2020 13:38:14 +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 Date: Fri, 17 Jul 2020 15:37:43 +0200 Message-Id: <20200717133753.127282-7-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 06/16] pwm: lpss: Use pwm_lpss_apply() when restoring state on resume X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Before this commit a suspend + resume of the LPSS PWM controller would result in the controller being reset to its defaults of output-freq = clock/256, duty-cycle=100%, until someone changes to the output-freq and/or duty-cycle are made. This problem has been masked so far because the main consumer (the i915 driver) was always making duty-cycle changes on resume. With the conversion of the i915 driver to the atomic PWM API the driver now only disables/enables the PWM on suspend/resume leaving the output-freq and duty as is, triggering this problem. The LPSS PWM controller has a mechanism where the ctrl register value and the actual base-unit and on-time-div values used are latched. When software sets the SW_UPDATE bit then at the end of the current PWM cycle, the new values from the ctrl-register will be latched into the actual registers, and the SW_UPDATE bit will be cleared. The problem is that before this commit our suspend/resume handling consisted of simply saving the PWM ctrl register on suspend and restoring it on resume, without setting the PWM_SW_UPDATE bit. When the controller has lost its state over a suspend/resume and thus has been reset to the defaults, just restoring the register is not enough. We must also set the SW_UPDATE bit to tell the controller to latch the restored values into the actual registers. Fixing this problem is not as simple as just or-ing in the value which is being restored with SW_UPDATE. If the PWM was enabled before we must write the new settings + PWM_SW_UPDATE before setting PWM_ENABLE. We must also wait for PWM_SW_UPDATE to become 0 again and depending on the model we must do this either before or after the setting of PWM_ENABLE. All the necessary logic for doing this is already present inside pwm_lpss_apply(), so instead of duplicating this inside the resume handler, this commit makes the resume handler use pwm_lpss_apply() to restore the settings when necessary. This fixes the output-freq and duty-cycle being reset to their defaults on resume. Signed-off-by: Hans de Goede --- Changes in v5: - The changes to pwm_lpss_apply() are much cleaner now thanks to the new pwm_lpss_prepare_enable() helper. Changes in v3: - This replaces the "pwm: lpss: Set SW_UPDATE bit when enabling the PWM" patch from previous versions of this patch-set, which really was a hack working around the resume issue which this patch fixes properly. --- drivers/pwm/pwm-lpss.c | 56 ++++++++++++++++++++++++++++++++++++------ 1 file changed, 48 insertions(+), 8 deletions(-) diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c index 8a136ba2a583..cf4eaf7ef2a2 100644 --- a/drivers/pwm/pwm-lpss.c +++ b/drivers/pwm/pwm-lpss.c @@ -143,29 +143,39 @@ static int pwm_lpss_prepare_enable(struct pwm_lpss_chip *lpwm, return 0; } -static int pwm_lpss_apply(struct pwm_chip *chip, struct pwm_device *pwm, - const struct pwm_state *state) +static int __pwm_lpss_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state, bool from_resume) { struct pwm_lpss_chip *lpwm = to_lpwm(chip); int ret = 0; if (state->enabled) { if (!pwm_is_enabled(pwm)) { - pm_runtime_get_sync(chip->dev); + if (!from_resume) + pm_runtime_get_sync(chip->dev); + ret = pwm_lpss_prepare_enable(lpwm, pwm, state, true); - if (ret) + if (ret && !from_resume) pm_runtime_put(chip->dev); } else { 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); + + if (!from_resume) + pm_runtime_put(chip->dev); } return ret; } +static int pwm_lpss_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + return __pwm_lpss_apply(chip, pwm, state, false); +} + static void pwm_lpss_get_state(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state) { @@ -278,10 +288,40 @@ EXPORT_SYMBOL_GPL(pwm_lpss_suspend); int pwm_lpss_resume(struct device *dev) { struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev); - int i; + struct pwm_state saved_state; + struct pwm_device *pwm; + int i, ret; + u32 ctrl; - for (i = 0; i < lpwm->info->npwm; i++) - writel(lpwm->saved_ctrl[i], lpwm->regs + i * PWM_SIZE + PWM); + for (i = 0; i < lpwm->info->npwm; i++) { + pwm = &lpwm->chip.pwms[i]; + + ctrl = pwm_lpss_read(pwm); + /* If we did not reach S0i3/S3 the controller keeps its state */ + if (ctrl == lpwm->saved_ctrl[i]) + continue; + + /* + * We cannot just blindly restore the old value here. Since we + * are changing the settings we must set SW_UPDATE and if the + * PWM was enabled before we must write the new settings + + * PWM_SW_UPDATE before setting PWM_ENABLE. We must also wait + * for PWM_SW_UPDATE to become 0 again and depending on the + * model we must do this either before or after the setting of + * PWM_ENABLE. + * So instead of reproducing all the code from pwm_apply() here, + * we just reapply the state as stored in pwm->state. + */ + saved_state = pwm->state; + /* + * Update enabled to its actual setting for the + * enabled<->disabled transitions inside apply(). + */ + pwm->state.enabled = !!(ctrl & PWM_ENABLE); + ret = __pwm_lpss_apply(&lpwm->chip, pwm, &saved_state, true); + if (ret) + dev_err(dev, "Error restoring state on resume\n"); + } return 0; } From patchwork Fri Jul 17 13:37:44 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: 11670301 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 A64C0618 for ; Fri, 17 Jul 2020 13:38:33 +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 8428620734 for ; Fri, 17 Jul 2020 13:38:33 +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="Wozoo7xn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8428620734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3EC1F6EDBC; Fri, 17 Jul 2020 13:38:31 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 E0A676EDBF for ; Fri, 17 Jul 2020 13:38:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993108; 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=N/xQY2ndEh9mW9MwVPKpVHE1H/7u+wSTzv3ok3js0g0=; b=Wozoo7xngYU8X6shlA4WnvecJ1H+WqEd1HUc2ktymky7EzxVsCKOie2Se6+Bl+0idhRrCf 7/ujgXLkviWmC9Z577F2nsPAzhPrAHAoPNI8hmkpzAUttfeyj+Heo/OScBhtj8T5dSwvKc lKw6zy4ub3UMVWF0GQL3PAbQYGnrDBY= 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-43-QCwneyZBPOGBum7Fsx1Fjw-1; Fri, 17 Jul 2020 09:38:25 -0400 X-MC-Unique: QCwneyZBPOGBum7Fsx1Fjw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7CC23102C80B; Fri, 17 Jul 2020 13:38:23 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id BE1BD8FA27; Fri, 17 Jul 2020 13:38:18 +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 Date: Fri, 17 Jul 2020 15:37:44 +0200 Message-Id: <20200717133753.127282-8-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 07/16] pwm: crc: Fix period / duty_cycle times being off by a factor of 256 X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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. Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- 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 Fri Jul 17 13:37:45 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: 11670303 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 57B7460D for ; Fri, 17 Jul 2020 13:38:40 +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 356C320734 for ; Fri, 17 Jul 2020 13:38:40 +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="hg2jT885" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 356C320734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A84B189E86; Fri, 17 Jul 2020 13:38:39 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 9869889E86 for ; Fri, 17 Jul 2020 13:38:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993117; 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=H8fH7uW7rjL+GZ+fftT+fw3GP/XhNeMys1Knw7XwAIE=; b=hg2jT885AO919YNBO2PyEZEfixeGzC0pmxA/++O3LjazCdgaRKQENL8CPt6MmoF8MS33GA Y/S2Cd/DDeKyRQFbGbRdoePuKUiRKoj1jTx7hSavvaQ2J5skAMx12bBVM19p3vYPuTohlP qvccEFYUfIQU0FglJ4zF6Dvf1kyRcHQ= 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-14-oXjO79EbOtaavpe2bjr5GA-1; Fri, 17 Jul 2020 09:38:35 -0400 X-MC-Unique: oXjO79EbOtaavpe2bjr5GA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B0F8E8EB971; Fri, 17 Jul 2020 13:38:33 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id C24228FA27; Fri, 17 Jul 2020 13:38:23 +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 Date: Fri, 17 Jul 2020 15:37:45 +0200 Message-Id: <20200717133753.127282-9-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 08/16] pwm: crc: Fix off-by-one error in the clock-divider calculations X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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). Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- 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 Fri Jul 17 13:37:46 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: 11670313 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 D097E13B6 for ; Fri, 17 Jul 2020 13:38:48 +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 AF4652076A for ; Fri, 17 Jul 2020 13:38:48 +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="T675Hh9w" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AF4652076A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 280766EDBA; Fri, 17 Jul 2020 13:38:48 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 97E426EDC1 for ; Fri, 17 Jul 2020 13:38:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993125; 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=EMbMxst1oiHtTJmDDNK1CEbufosoaisjf4HJnYds+98=; b=T675Hh9w9u9LRuxCrg8w0X/xcKr17OGfCftGS6eRbfgPimdzxJv/u1yrffMzBng/uXNw6+ 4VozLtGVh11XVtHNUo9EVSNrNGPm2LzXdeBZg5oM9n8rgfwDJCbjPG15vPqzsybhmtOvht MidhIgyo7tnUQ//LEFTCzqAasSJixeQ= 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-367-lVeEGG9RO4Sa2zkNWDP6_w-1; Fri, 17 Jul 2020 09:38:42 -0400 X-MC-Unique: lVeEGG9RO4Sa2zkNWDP6_w-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D4A121080; Fri, 17 Jul 2020 13:38:39 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 02D0E8FA27; Fri, 17 Jul 2020 13:38:33 +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 Date: Fri, 17 Jul 2020 15:37:46 +0200 Message-Id: <20200717133753.127282-10-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 09/16] pwm: crc: Fix period changes not having any effect X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 I strongly suspect that the BACKLIGHT_EN register at address 0x51 really controls a separate output-only GPIO which is connected to the LCD panels backlight-enable input. Like how the PANEL_EN register at address 0x52 controls an output-only GPIO which is earmarked for the LCD panel's enable pin. If this is correct then this GPIO should really be added to the gpio-crystalcove.c driver and the PWM driver should stop poking it. But I've been unable to come up with a definitive answer here, so I'm keeping this as is for now. 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. Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- 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 Fri Jul 17 13:37:47 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: 11670319 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 E8033618 for ; Fri, 17 Jul 2020 13:38:55 +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 C535F20759 for ; Fri, 17 Jul 2020 13:38:55 +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="UBZSccfJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C535F20759 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4DE9C6EDC3; Fri, 17 Jul 2020 13:38:55 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5212D6EDC3 for ; Fri, 17 Jul 2020 13:38:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993132; 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=4Ib64GzsX/8qSglGMuvDRtcc6hdwRktBSJO+EDu4u2I=; b=UBZSccfJznsp/69ftI8ERvt5rIZgSncKH4rw+aSdBaUM2SFMhQspxCYFYRz1Bwx3//pQI5 smIwd6f3ZQpsxSIL4PIG5bnxoWyqKHjH0+m1lA+r1Hn4Dwxb9W/ao9/RTXkkD711XIfOrq +hTJP21Ae8l2MG08EJRNe0Y9lRVr2HI= 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-313-dKUlCn-0PHCLOgOSO83cTQ-1; Fri, 17 Jul 2020 09:38:48 -0400 X-MC-Unique: dKUlCn-0PHCLOgOSO83cTQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2F8C08EB998; Fri, 17 Jul 2020 13:38:46 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 25B817BD7C; Fri, 17 Jul 2020 13:38:40 +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 Date: Fri, 17 Jul 2020 15:37:47 +0200 Message-Id: <20200717133753.127282-11-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 10/16] pwm: crc: Enable/disable PWM output on enable/disable X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- 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 Fri Jul 17 13:37:48 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: 11670323 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 6608213B6 for ; Fri, 17 Jul 2020 13:39:02 +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 4396C20775 for ; Fri, 17 Jul 2020 13:39:02 +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="PqVohLy3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4396C20775 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A42A56EDC5; Fri, 17 Jul 2020 13:39:01 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 555C4888AE for ; Fri, 17 Jul 2020 13:39:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993139; 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=rsgaSScqfqS4PRyzzf5oPN1LM95C1kF5r/jgzFwdEWU=; b=PqVohLy3Yg518sEOui7dCe8DdE9YjWwAHXwWKRVp+4vxzmvs/0q97SadbnFw58WaIXAWWX vkug8U77/U8kkaf9nPA25NUeddG8Pk9te5Kcv2IRhduG7LrGWcpEouBPSROUuVw2ayNbet hOpuECT0jRjNLWec04fnSQTm5uscx6A= 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-167-_C9LoJ8WPnuVuw4ikn3rcw-1; Fri, 17 Jul 2020 09:38:55 -0400 X-MC-Unique: _C9LoJ8WPnuVuw4ikn3rcw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A531319057A8; Fri, 17 Jul 2020 13:38:50 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 72F177BD7C; Fri, 17 Jul 2020 13:38:46 +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 Date: Fri, 17 Jul 2020 15:37:48 +0200 Message-Id: <20200717133753.127282-12-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 11/16] pwm: crc: Implement apply() method to support the new atomic PWM API X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Replace the enable, disable and config pwm_ops with an apply op, to support the new atomic PWM API. Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko --- Changes in v3: - Keep crc_pwm_calc_clk_div() helper to avoid needless churn --- drivers/pwm/pwm-crc.c | 89 ++++++++++++++++++++++++++----------------- 1 file changed, 53 insertions(+), 36 deletions(-) diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c index b72008c9b072..8a7f4707279c 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -51,59 +51,76 @@ 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)); - - regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div | PWM_OUTPUT_ENABLE); - regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1); - - return 0; -} - -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, - int duty_ns, int period_ns) -{ - struct crystalcove_pwm *crc_pwm = to_crc_pwm(c); + struct crystalcove_pwm *crc_pwm = to_crc_pwm(chip); struct device *dev = crc_pwm->chip.dev; - int level; + int err; - if (period_ns > PWM_MAX_PERIOD_NS) { + if (state->period > PWM_MAX_PERIOD_NS) { dev_err(dev, "un-supported period_ns\n"); return -EINVAL; } - if (pwm_get_period(pwm) != period_ns) { - int clk_div = crc_pwm_calc_clk_div(period_ns); + if (state->polarity != PWM_POLARITY_NORMAL) + return -EOPNOTSUPP; + + 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; + } + } + + if (pwm_get_duty_cycle(pwm) != state->duty_cycle || + pwm_get_period(pwm) != state->period) { + int level = state->duty_cycle * PWM_MAX_LEVEL / state->period; + 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_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 Fri Jul 17 13:37:49 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: 11670329 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 ADB6513B6 for ; Fri, 17 Jul 2020 13:39:06 +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 8C02A20734 for ; Fri, 17 Jul 2020 13:39:06 +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="E/ENw540" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C02A20734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0F37C6EDC6; Fri, 17 Jul 2020 13:39:06 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 EFBBA6EDC6 for ; Fri, 17 Jul 2020 13:39:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993144; 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=1V2c/64RZn70JrVNqYPs5uTiS7MghLouOUSREBgE3zw=; b=E/ENw540ORZ4zIs1aNsrp62ak//Z3Ml7c6z+70/bJxAGsCrHpRbulxZXYa4TgUENfkGJwo WTJXUf5bwNrYeclycFjv+4lzNY+f6Jq1vNwbBUjUj59+TfBZ9igb6UfMAgBWlAJA9S5JXq AQ39AKNcE4XVRDTfOmrczgGxxJ63yv8= 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-38-NlhfjF17PvqhAKI_cKxcvA-1; Fri, 17 Jul 2020 09:39:02 -0400 X-MC-Unique: NlhfjF17PvqhAKI_cKxcvA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B892D14A49; Fri, 17 Jul 2020 13:38:53 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id EA2CE8FA27; Fri, 17 Jul 2020 13:38:50 +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 Date: Fri, 17 Jul 2020 15:37:49 +0200 Message-Id: <20200717133753.127282-13-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 12/16] pwm: crc: Implement get_state() method X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Implement the pwm_ops.get_state() method to complete the support for the new atomic PWM API. Reviewed-by: Andy Shevchenko Signed-off-by: Hans de Goede --- 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 8a7f4707279c..370ab826a20b 100644 --- a/drivers/pwm/pwm-crc.c +++ b/drivers/pwm/pwm-crc.c @@ -119,8 +119,39 @@ 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(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 Fri Jul 17 13:37:50 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: 11670345 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 0ABE0618 for ; Fri, 17 Jul 2020 13:39:24 +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 DD48420734 for ; Fri, 17 Jul 2020 13:39:23 +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="dzkluc6m" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DD48420734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 151F36EDCA; Fri, 17 Jul 2020 13:39:23 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 B759C6EDCA for ; Fri, 17 Jul 2020 13:39:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993158; 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=0E358gUSBhGTotJA8GEwcHbmCx7Te/Sih/QfnaV6xJs=; b=dzkluc6mghKVCbtJLiC7Gl851H6If6reuJ6Zc+Aea8y4737nTYXB6CXxOSvlLEdEvVToiB Is5j7DdQjyHt6HI5v2eRH/7novbxVd8i9opQ+Mq0uPwLZy6tL2V+l+NUjwEdL90SpIs7x1 EckVF+9MWRZCOFJHPbeA718NL0DyZRE= 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-412-E5p5wfHEMOWmvwGIQj0xbQ-1; Fri, 17 Jul 2020 09:39:13 -0400 X-MC-Unique: E5p5wfHEMOWmvwGIQj0xbQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3259580BCCB; Fri, 17 Jul 2020 13:39:00 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 089428FA3C; Fri, 17 Jul 2020 13:38:53 +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 Date: Fri, 17 Jul 2020 15:37:50 +0200 Message-Id: <20200717133753.127282-14-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 13/16] drm/i915: panel: Add get_vbt_pwm_freq() helper X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 3c5056dbf607..8efdd9f08a08 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 Fri Jul 17 13:37:51 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: 11670337 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 7417B618 for ; Fri, 17 Jul 2020 13:39:21 +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 5260E20734 for ; Fri, 17 Jul 2020 13:39:21 +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="FOpVUDD8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5260E20734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AD6FF6EDC8; Fri, 17 Jul 2020 13:39:19 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 849636EDC8 for ; Fri, 17 Jul 2020 13:39:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993157; 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=cOeaPycuz3pd2BsD3TwE5ShVvLycX2FCdXrVRwJqqNk=; b=FOpVUDD8zW4FHCp5PQJPXBSPWW8DpLnbDfji5h2QqC0+Jb/9mlEQ31xkgHUiTvu8nN8+et EWPPJdXFdahVLbYTFQPcmil9wwwxinn6ERObR77FBT1kaJeYEeaPfALlMOwRUHRWIoXBOg eomJT9WJr19ss2qzDFhNmI/g49Karc0= 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-233-1VVgLKf2Mp6mXDdecFm5og-1; Fri, 17 Jul 2020 09:39:13 -0400 X-MC-Unique: 1VVgLKf2Mp6mXDdecFm5og-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6184A10BA; Fri, 17 Jul 2020 13:39:03 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 776CE8FA27; Fri, 17 Jul 2020 13:39:00 +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 Date: Fri, 17 Jul 2020 15:37:51 +0200 Message-Id: <20200717133753.127282-15-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [PATCH v5 14/16] drm/i915: panel: Honor the VBT PWM frequency for devs with an external PWM controller X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 2bf3d4cb4ea9..de32f9efb120 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 8efdd9f08a08..14e611c92194 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(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 Fri Jul 17 13:44:29 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: 11670353 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 6C2D560D for ; Fri, 17 Jul 2020 13:44:45 +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 4A7CC2076A for ; Fri, 17 Jul 2020 13:44:45 +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="b+39FTix" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4A7CC2076A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 730CA6EDD0; Fri, 17 Jul 2020 13:44:41 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@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 292976E0FA for ; Fri, 17 Jul 2020 13:44:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993479; 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=wFxzn0JHmm3vfb35/XuLlaLchu4vOFUQ8XAR0bQcpag=; b=b+39FTixLQpmnN3ZbF30zPR2QmFis0GrHCG8WhFnzTdkEPPOOoeb8LB7BDw2hERtmr5jAM r1FtpUfS5msOk8ggcNtANmMpR1/fadgHKW9xNhTio5cFIFWcABBxsY3fEQldE+WYHnmLVH owwfz+27IdJknT/KuK6RZunV1HUxi9c= 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-478-dNxV-KE6MJmm3_Gfli90Ow-1; Fri, 17 Jul 2020 09:44:36 -0400 X-MC-Unique: dNxV-KE6MJmm3_Gfli90Ow-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EDC36106B247; Fri, 17 Jul 2020 13:44:33 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4127E10013C0; Fri, 17 Jul 2020 13:44:31 +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 Date: Fri, 17 Jul 2020 15:44:29 +0200 Message-Id: <20200717134430.127575-1-hdegoede@redhat.com> In-Reply-To: <20200717133753.127282-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Subject: [Intel-gfx] [PATCH v5 15/16] drm/i915: panel: Honor the VBT PWM min setting for devs with an external PWM controller X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 14e611c92194..cb28b9908ca4 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(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 Fri Jul 17 13:44:30 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: 11670359 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 E10DD618 for ; Fri, 17 Jul 2020 13:44:48 +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 BF76C2076A for ; Fri, 17 Jul 2020 13:44:48 +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="A+ZQgbCQ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF76C2076A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4779A6EDD1; Fri, 17 Jul 2020 13:44:45 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from us-smtp-1.mimecast.com (us-smtp-1.mimecast.com [205.139.110.61]) by gabe.freedesktop.org (Postfix) with ESMTPS id AC9626EDCF for ; Fri, 17 Jul 2020 13:44:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594993482; 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=TvTZhPSdzExaa3NqVT5lrZowcWZbA2nAdgDfnfLh550=; b=A+ZQgbCQUKGT74ww9kATxPRwO6tHtzrCX+UMxZLq4ubnpiU+VTiYY1KZalvQ3XIgQ3BJF0 EIX3NYvycdHm612fv6ecJM4VNuCJ/tu9HuVSepT8JiHs69CO5zi6mHfAtNuJPvP6aMua7t FuGWUX7ZvX1kct4/YlGML8DFK/rw81U= 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-Qz7nQif4PPGmfrt5J-VdiQ-1; Fri, 17 Jul 2020 09:44:39 -0400 X-MC-Unique: Qz7nQif4PPGmfrt5J-VdiQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E8436800463; Fri, 17 Jul 2020 13:44:36 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-162.ams2.redhat.com [10.36.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4053E10013C0; Fri, 17 Jul 2020 13:44:34 +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 Date: Fri, 17 Jul 2020 15:44:30 +0200 Message-Id: <20200717134430.127575-2-hdegoede@redhat.com> In-Reply-To: <20200717134430.127575-1-hdegoede@redhat.com> References: <20200717133753.127282-1-hdegoede@redhat.com> <20200717134430.127575-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Subject: [Intel-gfx] [PATCH v5 16/16] drm/i915: panel: Use atomic PWM API for devs with an external PWM controller X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & 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, Andy Shevchenko , Mika Westerberg Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 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 | 71 +++++++++---------- 2 files changed, 34 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 de32f9efb120..4bd9981e70a1 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 cb28b9908ca4..3d97267c8238 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) { @@ -1916,36 +1915,30 @@ 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_get_period(panel->backlight.pwm)) { + /* PWM is already enabled, use existing settings */ + pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state); + + 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 / 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); } - level = DIV_ROUND_UP(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; - drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n", desc); return 0;