From patchwork Tue Jan 8 16:08:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Maarten Lankhorst X-Patchwork-Id: 10752303 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D7FD66C5 for ; Tue, 8 Jan 2019 16:08:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C83F4288B2 for ; Tue, 8 Jan 2019 16:08:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BC7DD28C16; Tue, 8 Jan 2019 16:08:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 5F39D288B2 for ; Tue, 8 Jan 2019 16:08:49 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 844D26EFAF; Tue, 8 Jan 2019 16:08:48 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mblankhorst.nl (mblankhorst.nl [IPv6:2a02:2308::216:3eff:fe92:dfa3]) by gabe.freedesktop.org (Postfix) with ESMTPS id 613BA6EB46 for ; Tue, 8 Jan 2019 16:08:45 +0000 (UTC) From: Maarten Lankhorst To: intel-gfx@lists.freedesktop.org Date: Tue, 8 Jan 2019 17:08:39 +0100 Message-Id: <20190108160842.13396-2-maarten.lankhorst@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190108160842.13396-1-maarten.lankhorst@linux.intel.com> References: <20190108160842.13396-1-maarten.lankhorst@linux.intel.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 2/5] drm/i915/backlight: Fix backlight takeover on LPT, v3. X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Hans de Goede , Tolga Cakir , Basil Eric Rabi Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP On lynxpoint the bios sometimes sets up the backlight using the CPU display, but the driver expects using the PWM PCH override register. Read the value from the CPU register, then convert it to the other units by converting from the old duty cycle, to freq, to the new units. This value is then programmed in the override register, after which we set the override and disable the CPU display control. This allows us to switch the source without flickering, and make the backlight controls work in the driver. Changes since v1: - Read BLC_PWM_CPU_CTL2 to cpu_ctl2. - Clean up cpu_mode if slightly. - Always disable BLM_PWM_ENABLE in cpu_ctl2. Changes since v2: - Simplify cpu_mode handling (Jani) Signed-off-by: Maarten Lankhorst Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108225 Cc: Basil Eric Rabi Cc: Hans de Goede Cc: Tolga Cakir Cc: Ville Syrjälä Tested-by: Tolga Cakir Cc: Jani Nikula Reviewed-by: Hans de Goede Reviewed-by: Jani Nikula --- drivers/gpu/drm/i915/intel_panel.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index f71b33cf1c97..1c9ef54d58fe 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -1493,8 +1493,8 @@ static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unus { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel; - u32 pch_ctl1, pch_ctl2, val; - bool alt; + u32 cpu_ctl2, pch_ctl1, pch_ctl2, val; + bool alt, cpu_mode; if (HAS_PCH_LPT(dev_priv)) alt = I915_READ(SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY; @@ -1508,6 +1508,8 @@ static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unus pch_ctl2 = I915_READ(BLC_PWM_PCH_CTL2); panel->backlight.max = pch_ctl2 >> 16; + cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2); + if (!panel->backlight.max) panel->backlight.max = get_backlight_max_vbt(connector); @@ -1516,12 +1518,28 @@ static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unus panel->backlight.min = get_backlight_min_vbt(connector); - val = lpt_get_backlight(connector); + panel->backlight.enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE; + + cpu_mode = panel->backlight.enabled && HAS_PCH_LPT(dev_priv) && + !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) && + (cpu_ctl2 & BLM_PWM_ENABLE); + if (cpu_mode) + val = pch_get_backlight(connector); + else + val = lpt_get_backlight(connector); val = intel_panel_compute_brightness(connector, val); panel->backlight.level = clamp(val, panel->backlight.min, panel->backlight.max); - panel->backlight.enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE; + if (cpu_mode) { + DRM_DEBUG_KMS("CPU backlight register was enabled, switching to PCH override\n"); + + /* Write converted CPU PWM value to PCH override register */ + lpt_set_backlight(connector->base.state, panel->backlight.level); + I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_OVERRIDE_ENABLE); + + I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2 & ~BLM_PWM_ENABLE); + } return 0; }