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From: "Mike Pagano" <mpagano@gentoo.org>
To: gentoo-commits@lists.gentoo.org
Subject: [gentoo-commits] proj/linux-patches:5.15 commit in: /
Date: Tue, 30 Nov 2021 00:49:45 +0000 (UTC)	[thread overview]
Message-ID: <1638233348.e9f26ab59b40c1bc915f2d074f3d37b12038af40.mpagano@gentoo> (raw)

commit:     e9f26ab59b40c1bc915f2d074f3d37b12038af40
Author:     Mike Pagano <mpagano <AT> gentoo <DOT> org>
AuthorDate: Tue Nov 30 00:49:08 2021 +0000
Commit:     Mike Pagano <mpagano <AT> gentoo <DOT> org>
CommitDate: Tue Nov 30 00:49:08 2021 +0000
URL:        https://gitweb.gentoo.org/proj/linux-patches.git/commit/?id=e9f26ab5

VESA patch needs fix

removing in case 5.15.6 comes out before I fix it

Signed-off-by: Mike Pagano <mpagano <AT> gentoo.org>

 0000_README                                        |   4 -
 ...15-PWM-support-for-VESA-backlight-helpers.patch | 618 ---------------------
 2 files changed, 622 deletions(-)

diff --git a/0000_README b/0000_README
index 0923a646..68d0c0db 100644
--- a/0000_README
+++ b/0000_README
@@ -75,10 +75,6 @@ Patch:  2000_BT-Check-key-sizes-only-if-Secure-Simple-Pairing-enabled.patch
 From:   https://lore.kernel.org/linux-bluetooth/20190522070540.48895-1-marcel@holtmann.org/raw
 Desc:   Bluetooth: Check key sizes only when Secure Simple Pairing is enabled. See bug #686758
 
-Patch:  2800_drm-i915-PWM-support-for-VESA-backlight-helpers.patch 
-From:   https://patchwork.freedesktop.org/series/95127/
-Desc:   drm/i915: Add support for panels with VESA backlights with PWM enable/disable
-
 Patch:  2900_tmp513-Fix-build-issue-by-selecting-CONFIG_REG.patch
 From:   https://bugs.gentoo.org/710790
 Desc:   tmp513 requies REGMAP_I2C to build.  Select it by default in Kconfig. See bug #710790. Thanks to Phil Stracchino

diff --git a/2800_drm-i915-PWM-support-for-VESA-backlight-helpers.patch b/2800_drm-i915-PWM-support-for-VESA-backlight-helpers.patch
deleted file mode 100644
index 45969bce..00000000
--- a/2800_drm-i915-PWM-support-for-VESA-backlight-helpers.patch
+++ /dev/null
@@ -1,618 +0,0 @@
-From patchwork Fri Nov  5 18:33:38 2021
-Content-Type: text/plain; charset="utf-8"
-MIME-Version: 1.0
-Content-Transfer-Encoding: 8bit
-Subject: [v5,1/5] drm/i915: Add support for panels with VESA backlights with
- PWM enable/disable
-From: Lyude Paul <lyude@redhat.com>
-X-Patchwork-Id: 462369
-Message-Id: <20211105183342.130810-2-lyude@redhat.com>
-To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
- intel-gfx@lists.freedesktop.org
-Cc: David Airlie <airlied@linux.ie>, open list <linux-kernel@vger.kernel.org>,
- stable@vger.kernel.org
-Date: Fri,  5 Nov 2021 14:33:38 -0400
-
-This simply adds proper support for panel backlights that can be controlled
-via VESA's backlight control protocol, but which also require that we
-enable and disable the backlight via PWM instead of via the DPCD interface.
-We also enable this by default, in order to fix some people's backlights
-that were broken by not having this enabled.
-
-For reference, backlights that require this and use VESA's backlight
-interface tend to be laptops with hybrid GPUs, but this very well may
-change in the future.
-
-v4:
-* Make sure that we call intel_backlight_level_to_pwm() in
-  intel_dp_aux_vesa_enable_backlight() - vsyrjala
-
-Signed-off-by: Lyude Paul <lyude@redhat.com>
-Link: https://gitlab.freedesktop.org/drm/intel/-/issues/3680
-Fixes: fe7d52bccab6 ("drm/i915/dp: Don't use DPCD backlights that need PWM enable/disable")
-Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
-Cc: <stable@vger.kernel.org> # v5.12+
----
- .../drm/i915/display/intel_dp_aux_backlight.c | 27 ++++++++++++++-----
- 1 file changed, 21 insertions(+), 6 deletions(-)
-
-diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-index 569d17b4d00f..f05b71c01b8e 100644
---- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-+++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-@@ -293,6 +293,13 @@ intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state,
- 	struct intel_panel *panel = &connector->panel;
- 	struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
- 
-+	if (!panel->backlight.edp.vesa.info.aux_enable) {
-+		u32 pwm_level = intel_backlight_invert_pwm_level(connector,
-+								 panel->backlight.pwm_level_max);
-+
-+		panel->backlight.pwm_funcs->enable(crtc_state, conn_state, pwm_level);
-+	}
-+
- 	drm_edp_backlight_enable(&intel_dp->aux, &panel->backlight.edp.vesa.info, level);
- }
- 
-@@ -304,6 +311,10 @@ static void intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state
- 	struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
- 
- 	drm_edp_backlight_disable(&intel_dp->aux, &panel->backlight.edp.vesa.info);
-+
-+	if (!panel->backlight.edp.vesa.info.aux_enable)
-+		panel->backlight.pwm_funcs->disable(old_conn_state,
-+						    intel_backlight_invert_pwm_level(connector, 0));
- }
- 
- static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector, enum pipe pipe)
-@@ -321,6 +332,15 @@ static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector,
- 	if (ret < 0)
- 		return ret;
- 
-+	if (!panel->backlight.edp.vesa.info.aux_enable) {
-+		ret = panel->backlight.pwm_funcs->setup(connector, pipe);
-+		if (ret < 0) {
-+			drm_err(&i915->drm,
-+				"Failed to setup PWM backlight controls for eDP backlight: %d\n",
-+				ret);
-+			return ret;
-+		}
-+	}
- 	panel->backlight.max = panel->backlight.edp.vesa.info.max;
- 	panel->backlight.min = 0;
- 	if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
-@@ -340,12 +360,7 @@ intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector)
- 	struct intel_dp *intel_dp = intel_attached_dp(connector);
- 	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
- 
--	/* TODO: We currently only support AUX only backlight configurations, not backlights which
--	 * require a mix of PWM and AUX controls to work. In the mean time, these machines typically
--	 * work just fine using normal PWM controls anyway.
--	 */
--	if ((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) &&
--	    drm_edp_backlight_supported(intel_dp->edp_dpcd)) {
-+	if (drm_edp_backlight_supported(intel_dp->edp_dpcd)) {
- 		drm_dbg_kms(&i915->drm, "AUX Backlight Control Supported!\n");
- 		return true;
- 	}
-
-From patchwork Fri Nov  5 18:33:39 2021
-Content-Type: text/plain; charset="utf-8"
-MIME-Version: 1.0
-Content-Transfer-Encoding: 7bit
-Subject: [v5,2/5] drm/nouveau/kms/nv50-: Explicitly check DPCD backlights for
- aux enable/brightness
-From: Lyude Paul <lyude@redhat.com>
-X-Patchwork-Id: 462371
-Message-Id: <20211105183342.130810-3-lyude@redhat.com>
-To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
- intel-gfx@lists.freedesktop.org
-Cc: David Airlie <airlied@linux.ie>, Ben Skeggs <bskeggs@redhat.com>,
- Karol Herbst <kherbst@redhat.com>, open list <linux-kernel@vger.kernel.org>
-Date: Fri,  5 Nov 2021 14:33:39 -0400
-
-Since we don't support hybrid AUX/PWM backlights in nouveau right now,
-let's add some explicit checks so that we don't break nouveau once we
-enable support for these backlights in other drivers.
-
-Reviewed-by: Karol Herbst <kherbst@redhat.com>
-Signed-off-by: Lyude Paul <lyude@redhat.com>
----
- drivers/gpu/drm/nouveau/nouveau_backlight.c | 5 ++++-
- 1 file changed, 4 insertions(+), 1 deletion(-)
-
-diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c
-index 1cbd71abc80a..ae2f2abc8f5a 100644
---- a/drivers/gpu/drm/nouveau/nouveau_backlight.c
-+++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c
-@@ -308,7 +308,10 @@ nv50_backlight_init(struct nouveau_backlight *bl,
- 		if (ret < 0)
- 			return ret;
- 
--		if (drm_edp_backlight_supported(edp_dpcd)) {
-+		/* TODO: Add support for hybrid PWM/DPCD panels */
-+		if (drm_edp_backlight_supported(edp_dpcd) &&
-+		    (edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) &&
-+		    (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP)) {
- 			NV_DEBUG(drm, "DPCD backlight controls supported on %s\n",
- 				 nv_conn->base.name);
- 
-
-From patchwork Fri Nov  5 18:33:40 2021
-Content-Type: text/plain; charset="utf-8"
-MIME-Version: 1.0
-Content-Transfer-Encoding: 7bit
-Subject: [v5,3/5] drm/dp: Don't read back backlight mode in
- drm_edp_backlight_enable()
-From: Lyude Paul <lyude@redhat.com>
-X-Patchwork-Id: 462376
-Message-Id: <20211105183342.130810-4-lyude@redhat.com>
-To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
- intel-gfx@lists.freedesktop.org
-Cc: Thomas Zimmermann <tzimmermann@suse.de>, David Airlie <airlied@linux.ie>,
- open list <linux-kernel@vger.kernel.org>, Maxime Ripard <mripard@kernel.org>
-Date: Fri,  5 Nov 2021 14:33:40 -0400
-
-As it turns out, apparently some machines will actually leave additional
-backlight functionality like dynamic backlight control on before the OS
-loads. Currently we don't take care to disable unsupported features when
-writing back the backlight mode, which can lead to some rather strange
-looking behavior when adjusting the backlight.
-
-So, let's fix this by just not reading back the current backlight mode on
-initial enable. I don't think there should really be any downsides to this,
-and this will ensure we don't leave any unsupported functionality enabled.
-
-This should fix at least one (but not all) of the issues seen with DPCD
-backlight support on fi-bdw-samus
-
-v5:
-* Just avoid reading back DPCD register - Doug Anderson
-
-Signed-off-by: Lyude Paul <lyude@redhat.com>
-Fixes: 867cf9cd73c3 ("drm/dp: Extract i915's eDP backlight code into DRM helpers")
-Reviewed-by: Douglas Anderson <dianders@chromium.org>
----
- drivers/gpu/drm/drm_dp_helper.c | 40 ++++++++++-----------------------
- 1 file changed, 12 insertions(+), 28 deletions(-)
-
-diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
-index ada0a1ff262d..af2aad2f4725 100644
---- a/drivers/gpu/drm/drm_dp_helper.c
-+++ b/drivers/gpu/drm/drm_dp_helper.c
-@@ -3363,27 +3363,13 @@ int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backli
- 			     const u16 level)
- {
- 	int ret;
--	u8 dpcd_buf, new_dpcd_buf;
-+	u8 dpcd_buf = DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD;
- 
--	ret = drm_dp_dpcd_readb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf);
--	if (ret != 1) {
--		drm_dbg_kms(aux->drm_dev,
--			    "%s: Failed to read backlight mode: %d\n", aux->name, ret);
--		return ret < 0 ? ret : -EIO;
--	}
--
--	new_dpcd_buf = dpcd_buf;
--
--	if ((dpcd_buf & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK) != DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
--		new_dpcd_buf &= ~DP_EDP_BACKLIGHT_CONTROL_MODE_MASK;
--		new_dpcd_buf |= DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD;
--
--		if (bl->pwmgen_bit_count) {
--			ret = drm_dp_dpcd_writeb(aux, DP_EDP_PWMGEN_BIT_COUNT, bl->pwmgen_bit_count);
--			if (ret != 1)
--				drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux pwmgen bit count: %d\n",
--					    aux->name, ret);
--		}
-+	if (bl->pwmgen_bit_count) {
-+		ret = drm_dp_dpcd_writeb(aux, DP_EDP_PWMGEN_BIT_COUNT, bl->pwmgen_bit_count);
-+		if (ret != 1)
-+			drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux pwmgen bit count: %d\n",
-+				    aux->name, ret);
- 	}
- 
- 	if (bl->pwm_freq_pre_divider) {
-@@ -3393,16 +3379,14 @@ int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backli
- 				    "%s: Failed to write aux backlight frequency: %d\n",
- 				    aux->name, ret);
- 		else
--			new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE;
-+			dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE;
- 	}
- 
--	if (new_dpcd_buf != dpcd_buf) {
--		ret = drm_dp_dpcd_writeb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, new_dpcd_buf);
--		if (ret != 1) {
--			drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux backlight mode: %d\n",
--				    aux->name, ret);
--			return ret < 0 ? ret : -EIO;
--		}
-+	ret = drm_dp_dpcd_writeb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, dpcd_buf);
-+	if (ret != 1) {
-+		drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux backlight mode: %d\n",
-+			    aux->name, ret);
-+		return ret < 0 ? ret : -EIO;
- 	}
- 
- 	ret = drm_edp_backlight_set_level(aux, bl, level);
-
-From patchwork Fri Nov  5 18:33:41 2021
-Content-Type: text/plain; charset="utf-8"
-MIME-Version: 1.0
-Content-Transfer-Encoding: 7bit
-Subject: [v5,4/5] drm/dp,
- drm/i915: Add support for VESA backlights using PWM for brightness control
-From: Lyude Paul <lyude@redhat.com>
-X-Patchwork-Id: 462379
-Message-Id: <20211105183342.130810-5-lyude@redhat.com>
-To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
- intel-gfx@lists.freedesktop.org
-Cc: Rajeev Nandan <rajeevny@codeaurora.org>, David Airlie <airlied@linux.ie>,
- Doug Anderson <dianders@chromium.org>, Maxime Ripard <mripard@kernel.org>,
- open list <linux-kernel@vger.kernel.org>,
- Thomas Zimmermann <tzimmermann@suse.de>
-Date: Fri,  5 Nov 2021 14:33:41 -0400
-
-Now that we've added support to i915 for controlling panel backlights that
-need PWM to be enabled/disabled, let's finalize this and add support for
-controlling brightness levels via PWM as well. This should hopefully put us
-towards the path of supporting _ALL_ backlights via VESA's DPCD interface
-which would allow us to finally start trusting the DPCD again.
-
-Note however that we still don't enable using this by default on i915 when
-it's not needed, primarily because I haven't yet had a chance to confirm if
-it's safe to do this on the one machine in Intel's CI that had an issue
-with this: samus-fi-bdw. I have done basic testing of this on other
-machines though, by manually patching i915 to force it into PWM-only mode
-on some of my laptops.
-
-v2:
-* Correct documentation (thanks Doug!)
-* Get rid of backlight caps
-
-Signed-off-by: Lyude Paul <lyude@redhat.com>
-Reviewed-by: Doug Anderson <dianders@chromium.org>
-Cc: Rajeev Nandan <rajeevny@codeaurora.org>
-Cc: Satadru Pramanik <satadru@gmail.com>
----
- drivers/gpu/drm/drm_dp_helper.c               | 72 +++++++++++++------
- .../drm/i915/display/intel_dp_aux_backlight.c | 44 +++++++++---
- include/drm/drm_dp_helper.h                   |  7 +-
- 3 files changed, 89 insertions(+), 34 deletions(-)
-
-diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
-index af2aad2f4725..23f9073bc473 100644
---- a/drivers/gpu/drm/drm_dp_helper.c
-+++ b/drivers/gpu/drm/drm_dp_helper.c
-@@ -3290,6 +3290,10 @@ int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_bac
- 	int ret;
- 	u8 buf[2] = { 0 };
- 
-+	/* The panel uses the PWM for controlling brightness levels */
-+	if (!bl->aux_set)
-+		return 0;
-+
- 	if (bl->lsb_reg_used) {
- 		buf[0] = (level & 0xff00) >> 8;
- 		buf[1] = (level & 0x00ff);
-@@ -3316,7 +3320,7 @@ drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct drm_edp_backli
- 	int ret;
- 	u8 buf;
- 
--	/* The panel uses something other then DPCD for enabling its backlight */
-+	/* This panel uses the EDP_BL_PWR GPIO for enablement */
- 	if (!bl->aux_enable)
- 		return 0;
- 
-@@ -3351,11 +3355,11 @@ drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct drm_edp_backli
-  * restoring any important backlight state such as the given backlight level, the brightness byte
-  * count, backlight frequency, etc.
-  *
-- * Note that certain panels, while supporting brightness level controls over DPCD, may not support
-- * having their backlights enabled via the standard %DP_EDP_DISPLAY_CONTROL_REGISTER. On such panels
-- * &drm_edp_backlight_info.aux_enable will be set to %false, this function will skip the step of
-- * programming the %DP_EDP_DISPLAY_CONTROL_REGISTER, and the driver must perform the required
-- * implementation specific step for enabling the backlight after calling this function.
-+ * Note that certain panels do not support being enabled or disabled via DPCD, but instead require
-+ * that the driver handle enabling/disabling the panel through implementation-specific means using
-+ * the EDP_BL_PWR GPIO. For such panels, &drm_edp_backlight_info.aux_enable will be set to %false,
-+ * this function becomes a no-op, and the driver is expected to handle powering the panel on using
-+ * the EDP_BL_PWR GPIO.
-  *
-  * Returns: %0 on success, negative error code on failure.
-  */
-@@ -3363,7 +3367,12 @@ int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backli
- 			     const u16 level)
- {
- 	int ret;
--	u8 dpcd_buf = DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD;
-+	u8 dpcd_buf;
-+
-+	if (bl->aux_set)
-+		dpcd_buf = DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD;
-+	else
-+		dpcd_buf = DP_EDP_BACKLIGHT_CONTROL_MODE_PWM;
- 
- 	if (bl->pwmgen_bit_count) {
- 		ret = drm_dp_dpcd_writeb(aux, DP_EDP_PWMGEN_BIT_COUNT, bl->pwmgen_bit_count);
-@@ -3405,12 +3414,13 @@ EXPORT_SYMBOL(drm_edp_backlight_enable);
-  * @aux: The DP AUX channel to use
-  * @bl: Backlight capability info from drm_edp_backlight_init()
-  *
-- * This function handles disabling DPCD backlight controls on a panel over AUX. Note that some
-- * panels have backlights that are enabled/disabled by other means, despite having their brightness
-- * values controlled through DPCD. On such panels &drm_edp_backlight_info.aux_enable will be set to
-- * %false, this function will become a no-op (and we will skip updating
-- * %DP_EDP_DISPLAY_CONTROL_REGISTER), and the driver must take care to perform it's own
-- * implementation specific step for disabling the backlight.
-+ * This function handles disabling DPCD backlight controls on a panel over AUX.
-+ *
-+ * Note that certain panels do not support being enabled or disabled via DPCD, but instead require
-+ * that the driver handle enabling/disabling the panel through implementation-specific means using
-+ * the EDP_BL_PWR GPIO. For such panels, &drm_edp_backlight_info.aux_enable will be set to %false,
-+ * this function becomes a no-op, and the driver is expected to handle powering the panel off using
-+ * the EDP_BL_PWR GPIO.
-  *
-  * Returns: %0 on success or no-op, negative error code on failure.
-  */
-@@ -3434,6 +3444,9 @@ drm_edp_backlight_probe_max(struct drm_dp_aux *aux, struct drm_edp_backlight_inf
- 	int ret;
- 	u8 pn, pn_min, pn_max;
- 
-+	if (!bl->aux_set)
-+		return 0;
-+
- 	ret = drm_dp_dpcd_readb(aux, DP_EDP_PWMGEN_BIT_COUNT, &pn);
- 	if (ret != 1) {
- 		drm_dbg_kms(aux->drm_dev, "%s: Failed to read pwmgen bit count cap: %d\n",
-@@ -3519,7 +3532,7 @@ drm_edp_backlight_probe_max(struct drm_dp_aux *aux, struct drm_edp_backlight_inf
- }
- 
- static inline int
--drm_edp_backlight_probe_level(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl,
-+drm_edp_backlight_probe_state(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl,
- 			      u8 *current_mode)
- {
- 	int ret;
-@@ -3534,6 +3547,9 @@ drm_edp_backlight_probe_level(struct drm_dp_aux *aux, struct drm_edp_backlight_i
- 	}
- 
- 	*current_mode = (mode_reg & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK);
-+	if (!bl->aux_set)
-+		return 0;
-+
- 	if (*current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
- 		int size = 1 + bl->lsb_reg_used;
- 
-@@ -3564,7 +3580,7 @@ drm_edp_backlight_probe_level(struct drm_dp_aux *aux, struct drm_edp_backlight_i
-  * @bl: The &drm_edp_backlight_info struct to fill out with information on the backlight
-  * @driver_pwm_freq_hz: Optional PWM frequency from the driver in hz
-  * @edp_dpcd: A cached copy of the eDP DPCD
-- * @current_level: Where to store the probed brightness level
-+ * @current_level: Where to store the probed brightness level, if any
-  * @current_mode: Where to store the currently set backlight control mode
-  *
-  * Initializes a &drm_edp_backlight_info struct by probing @aux for it's backlight capabilities,
-@@ -3584,24 +3600,38 @@ drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl
- 
- 	if (edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP)
- 		bl->aux_enable = true;
-+	if (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP)
-+		bl->aux_set = true;
- 	if (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT)
- 		bl->lsb_reg_used = true;
- 
-+	/* Sanity check caps */
-+	if (!bl->aux_set && !(edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP)) {
-+		drm_dbg_kms(aux->drm_dev,
-+			    "%s: Panel supports neither AUX or PWM brightness control? Aborting\n",
-+			    aux->name);
-+		return -EINVAL;
-+	}
-+
- 	ret = drm_edp_backlight_probe_max(aux, bl, driver_pwm_freq_hz, edp_dpcd);
- 	if (ret < 0)
- 		return ret;
- 
--	ret = drm_edp_backlight_probe_level(aux, bl, current_mode);
-+	ret = drm_edp_backlight_probe_state(aux, bl, current_mode);
- 	if (ret < 0)
- 		return ret;
- 	*current_level = ret;
- 
- 	drm_dbg_kms(aux->drm_dev,
--		    "%s: Found backlight level=%d/%d pwm_freq_pre_divider=%d mode=%x\n",
--		    aux->name, *current_level, bl->max, bl->pwm_freq_pre_divider, *current_mode);
--	drm_dbg_kms(aux->drm_dev,
--		    "%s: Backlight caps: pwmgen_bit_count=%d lsb_reg_used=%d aux_enable=%d\n",
--		    aux->name, bl->pwmgen_bit_count, bl->lsb_reg_used, bl->aux_enable);
-+		    "%s: Found backlight: aux_set=%d aux_enable=%d mode=%d\n",
-+		    aux->name, bl->aux_set, bl->aux_enable, *current_mode);
-+	if (bl->aux_set) {
-+		drm_dbg_kms(aux->drm_dev,
-+			    "%s: Backlight caps: level=%d/%d pwm_freq_pre_divider=%d lsb_reg_used=%d\n",
-+			    aux->name, *current_level, bl->max, bl->pwm_freq_pre_divider,
-+			    bl->lsb_reg_used);
-+	}
-+
- 	return 0;
- }
- EXPORT_SYMBOL(drm_edp_backlight_init);
-diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-index f05b71c01b8e..96fe3eaba44a 100644
---- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-+++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-@@ -282,6 +282,12 @@ intel_dp_aux_vesa_set_backlight(const struct drm_connector_state *conn_state, u3
- 	struct intel_panel *panel = &connector->panel;
- 	struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
- 
-+	if (!panel->backlight.edp.vesa.info.aux_set) {
-+		const u32 pwm_level = intel_backlight_level_to_pwm(connector, level);
-+
-+		intel_backlight_set_pwm_level(conn_state, pwm_level);
-+	}
-+
- 	drm_edp_backlight_set_level(&intel_dp->aux, &panel->backlight.edp.vesa.info, level);
- }
- 
-@@ -294,8 +300,13 @@ intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state,
- 	struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
- 
- 	if (!panel->backlight.edp.vesa.info.aux_enable) {
--		u32 pwm_level = intel_backlight_invert_pwm_level(connector,
--								 panel->backlight.pwm_level_max);
-+		u32 pwm_level;
-+
-+		if (!panel->backlight.edp.vesa.info.aux_set)
-+			pwm_level = intel_backlight_level_to_pwm(connector, level);
-+		else
-+			pwm_level = intel_backlight_invert_pwm_level(connector,
-+								     panel->backlight.pwm_level_max);
- 
- 		panel->backlight.pwm_funcs->enable(crtc_state, conn_state, pwm_level);
- 	}
-@@ -332,7 +343,7 @@ static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector,
- 	if (ret < 0)
- 		return ret;
- 
--	if (!panel->backlight.edp.vesa.info.aux_enable) {
-+	if (!panel->backlight.edp.vesa.info.aux_set || !panel->backlight.edp.vesa.info.aux_enable) {
- 		ret = panel->backlight.pwm_funcs->setup(connector, pipe);
- 		if (ret < 0) {
- 			drm_err(&i915->drm,
-@@ -341,14 +352,27 @@ static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector,
- 			return ret;
- 		}
- 	}
--	panel->backlight.max = panel->backlight.edp.vesa.info.max;
--	panel->backlight.min = 0;
--	if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
--		panel->backlight.level = current_level;
--		panel->backlight.enabled = panel->backlight.level != 0;
-+
-+	if (panel->backlight.edp.vesa.info.aux_set) {
-+		panel->backlight.max = panel->backlight.edp.vesa.info.max;
-+		panel->backlight.min = 0;
-+		if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
-+			panel->backlight.level = current_level;
-+			panel->backlight.enabled = panel->backlight.level != 0;
-+		} else {
-+			panel->backlight.level = panel->backlight.max;
-+			panel->backlight.enabled = false;
-+		}
- 	} else {
--		panel->backlight.level = panel->backlight.max;
--		panel->backlight.enabled = false;
-+		panel->backlight.max = panel->backlight.pwm_level_max;
-+		panel->backlight.min = panel->backlight.pwm_level_min;
-+		if (current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_PWM) {
-+			panel->backlight.level = panel->backlight.pwm_funcs->get(connector, pipe);
-+			panel->backlight.enabled = panel->backlight.pwm_enabled;
-+		} else {
-+			panel->backlight.level = panel->backlight.max;
-+			panel->backlight.enabled = false;
-+		}
- 	}
- 
- 	return 0;
-diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
-index afdf7f4183f9..8b2ed4199284 100644
---- a/include/drm/drm_dp_helper.h
-+++ b/include/drm/drm_dp_helper.h
-@@ -1868,7 +1868,7 @@ drm_dp_sink_can_do_video_without_timing_msa(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
-  *
-  * Note that currently this function will return %false for panels which support various DPCD
-  * backlight features but which require the brightness be set through PWM, and don't support setting
-- * the brightness level via the DPCD. This is a TODO.
-+ * the brightness level via the DPCD.
-  *
-  * Returns: %True if @edp_dpcd indicates that VESA backlight controls are supported, %false
-  * otherwise
-@@ -1876,8 +1876,7 @@ drm_dp_sink_can_do_video_without_timing_msa(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
- static inline bool
- drm_edp_backlight_supported(const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE])
- {
--	return (edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP) &&
--		(edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP);
-+	return !!(edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP);
- }
- 
- /*
-@@ -2238,6 +2237,7 @@ drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk)
-  * @max: The maximum backlight level that may be set
-  * @lsb_reg_used: Do we also write values to the DP_EDP_BACKLIGHT_BRIGHTNESS_LSB register?
-  * @aux_enable: Does the panel support the AUX enable cap?
-+ * @aux_set: Does the panel support setting the brightness through AUX?
-  *
-  * This structure contains various data about an eDP backlight, which can be populated by using
-  * drm_edp_backlight_init().
-@@ -2249,6 +2249,7 @@ struct drm_edp_backlight_info {
- 
- 	bool lsb_reg_used : 1;
- 	bool aux_enable : 1;
-+	bool aux_set : 1;
- };
- 
- int
-
-From patchwork Fri Nov  5 18:33:42 2021
-Content-Type: text/plain; charset="utf-8"
-MIME-Version: 1.0
-Content-Transfer-Encoding: 8bit
-Subject: [v5,5/5] drm/i915: Clarify probing order in
- intel_dp_aux_init_backlight_funcs()
-From: Lyude Paul <lyude@redhat.com>
-X-Patchwork-Id: 462382
-Message-Id: <20211105183342.130810-6-lyude@redhat.com>
-To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
- intel-gfx@lists.freedesktop.org
-Cc: David Airlie <airlied@linux.ie>, open list <linux-kernel@vger.kernel.org>
-Date: Fri,  5 Nov 2021 14:33:42 -0400
-
-Hooray! We've managed to hit enough bugs upstream that I've been able to
-come up with a pretty solid explanation for how backlight controls are
-actually supposed to be detected and used these days. As well, having the
-rest of the PWM bits in VESA's backlight interface implemented seems to
-have fixed all of the problematic brightness controls laptop panels that
-we've hit so far.
-
-So, let's actually document this instead of just calling the laptop panels
-liars. As well, I would like to formally apologize to all of the laptop
-panels I called liars. I'm sorry laptop panels, hopefully you can all
-forgive me and we can move past this~
-
-Signed-off-by: Lyude Paul <lyude@redhat.com>
-Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
----
- .../drm/i915/display/intel_dp_aux_backlight.c    | 16 +++++++++++-----
- 1 file changed, 11 insertions(+), 5 deletions(-)
-
-diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-index 96fe3eaba44a..8b9c925c4c16 100644
---- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-+++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
-@@ -456,11 +456,17 @@ int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector)
- 	}
- 
- 	/*
--	 * A lot of eDP panels in the wild will report supporting both the
--	 * Intel proprietary backlight control interface, and the VESA
--	 * backlight control interface. Many of these panels are liars though,
--	 * and will only work with the Intel interface. So, always probe for
--	 * that first.
-+	 * Since Intel has their own backlight control interface, the majority of machines out there
-+	 * using DPCD backlight controls with Intel GPUs will be using this interface as opposed to
-+	 * the VESA interface. However, other GPUs (such as Nvidia's) will always use the VESA
-+	 * interface. This means that there's quite a number of panels out there that will advertise
-+	 * support for both interfaces, primarily systems with Intel/Nvidia hybrid GPU setups.
-+	 *
-+	 * There's a catch to this though: on many panels that advertise support for both
-+	 * interfaces, the VESA backlight interface will stop working once we've programmed the
-+	 * panel with Intel's OUI - which is also required for us to be able to detect Intel's
-+	 * backlight interface at all. This means that the only sensible way for us to detect both
-+	 * interfaces is to probe for Intel's first, and VESA's second.
- 	 */
- 	if (try_intel_interface && intel_dp_aux_supports_hdr_backlight(connector)) {
- 		drm_dbg_kms(dev, "Using Intel proprietary eDP backlight controls\n");


             reply	other threads:[~2021-11-30  0:50 UTC|newest]

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