[RFC][PATCH 0/5 v3] adv7511 EDID probing improvements

[RFC][PATCH 0/5 v3] adv7511 EDID probing improvements

[John Stultz]

Wanted to send out v3 of this patch set improving the EDID
probing on the adv7511 used on HiKey.

The first three patches are fixups that are hopefully straight
forward, integrating feedback I got from Laurant.

The last two patches try to clean up and resue code to avoid
an issue I'm seeing where something is going wrong with the
regmap cache state for the ADV7511_REG_EDID_I2C_ADDR (0x43)
register which results in i2c_transfer errors if we don't do the
regcache_sync/_mark_dirty() calls. I suspect there might be a
better solution there, so suggestions will be very welcome.

Thoughts and feedback would be appreciated!

thanks
-john

New in v3:
* Addressed naming improvements and drm_kms_helper_hotplug_event
  usage corrections as suggested by Laurent.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org

Archit Taneja (1):
  drm/bridge: adv7511: Enable HPD interrupts to support hotplug and
    improve monitor detection

John Stultz (4):
  drm/bridge: adv7511: Use work_struct to defer hotplug handing to out
    of irq context
  drm/bridge: adv7511: Switch to using drm_kms_helper_hotplug_event()
  drm/bridge: adv7511: Rework adv7511_power_on/off() so they can be
    reused internally
  drm/bridge: adv7511: Reuse __adv7511_power_on/off() when probing EDID

 drivers/gpu/drm/bridge/adv7511/adv7511.h     |  2 +
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 62 +++++++++++++++++++---------
 2 files changed, 44 insertions(+), 20 deletions(-)

-- 
2.7.4

[RFC][PATCH 0/5 v3] adv7511 EDID probing improvements

[John Stultz]

Wanted to send out v3 of this patch set improving the EDID
probing on the adv7511 used on HiKey.

The first three patches are fixups that are hopefully straight
forward, integrating feedback I got from Laurant.

The last two patches try to clean up and resue code to avoid
an issue I'm seeing where something is going wrong with the
regmap cache state for the ADV7511_REG_EDID_I2C_ADDR (0x43)
register which results in i2c_transfer errors if we don't do the
regcache_sync/_mark_dirty() calls. I suspect there might be a
better solution there, so suggestions will be very welcome.

Thoughts and feedback would be appreciated!

thanks
-john

New in v3:
* Addressed naming improvements and drm_kms_helper_hotplug_event
  usage corrections as suggested by Laurent.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org

Archit Taneja (1):
  drm/bridge: adv7511: Enable HPD interrupts to support hotplug and
    improve monitor detection

John Stultz (4):
  drm/bridge: adv7511: Use work_struct to defer hotplug handing to out
    of irq context
  drm/bridge: adv7511: Switch to using drm_kms_helper_hotplug_event()
  drm/bridge: adv7511: Rework adv7511_power_on/off() so they can be
    reused internally
  drm/bridge: adv7511: Reuse __adv7511_power_on/off() when probing EDID

 drivers/gpu/drm/bridge/adv7511/adv7511.h     |  2 +
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 62 +++++++++++++++++++---------
 2 files changed, 44 insertions(+), 20 deletions(-)

-- 
2.7.4

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[RFC][PATCH 1/5 v3] drm/bridge: adv7511: Use work_struct to defer hotplug handing to out of irq context

[John Stultz]

I was recently seeing issues with EDID probing, where
the logic to wait for the EDID read bit to be set by the
IRQ wasn't happening and the code would time out and fail.

Digging deeper, I found this was due to the fact that
IRQs were disabled as we were running in IRQ context from
the HPD signal.

Thus this patch changes the logic to handle the HPD signal
via a work_struct so we can be out of irq context.

With this patch, the EDID probing on hotplug does not time
out.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
v3: Rename irq_work to hpd_work and remove extra whitespace, as
    suggested by Laurent
---
 drivers/gpu/drm/bridge/adv7511/adv7511.h     |  2 ++
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 11 ++++++++++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h
index 992d76c..0396791 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511.h
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h
@@ -317,6 +317,8 @@ struct adv7511 {
 	bool edid_read;
 
 	wait_queue_head_t wq;
+	struct work_struct hpd_work;
+
 	struct drm_bridge bridge;
 	struct drm_connector connector;
 
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index 8dba729..4fcea44 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -402,6 +402,13 @@ static bool adv7511_hpd(struct adv7511 *adv7511)
 	return false;
 }
 
+static void adv7511_hpd_work(struct work_struct *work)
+{
+	struct adv7511 *adv7511 = container_of(work, struct adv7511, hpd_work);
+
+	drm_helper_hpd_irq_event(adv7511->connector.dev);
+}
+
 static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd)
 {
 	unsigned int irq0, irq1;
@@ -419,7 +426,7 @@ static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd)
 	regmap_write(adv7511->regmap, ADV7511_REG_INT(1), irq1);
 
 	if (process_hpd && irq0 & ADV7511_INT0_HPD && adv7511->bridge.encoder)
-		drm_helper_hpd_irq_event(adv7511->connector.dev);
+		schedule_work(&adv7511->hpd_work);
 
 	if (irq0 & ADV7511_INT0_EDID_READY || irq1 & ADV7511_INT1_DDC_ERROR) {
 		adv7511->edid_read = true;
@@ -1006,6 +1013,8 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 			goto err_i2c_unregister_edid;
 	}
 
+	INIT_WORK(&adv7511->hpd_work, adv7511_hpd_work);
+
 	if (i2c->irq) {
 		init_waitqueue_head(&adv7511->wq);
 
-- 
2.7.4

[RFC][PATCH 2/5 v3] drm/bridge: adv7511: Switch to using drm_kms_helper_hotplug_event()

[John Stultz]

In chasing down a previous issue with EDID probing from calling
drm_helper_hpd_irq_event() from irq context, Laurent noticed
that the DRM documentation suggests that
drm_kms_helper_hotplug_event() should be used instead.

Thus this patch replaces drm_helper_hpd_irq_event() with
drm_kms_helper_hotplug_event(), which requires we update the
connector.status entry and only call _hotplug_event() when the
status changes.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
v3: Update connector.status value and only call __hotplug_event()
    when that status changes, as suggested by Laurent.
---
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index 4fcea44..d93d66f 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -405,8 +405,22 @@ static bool adv7511_hpd(struct adv7511 *adv7511)
 static void adv7511_hpd_work(struct work_struct *work)
 {
 	struct adv7511 *adv7511 = container_of(work, struct adv7511, hpd_work);
+	enum drm_connector_status status;
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(adv7511->regmap, ADV7511_REG_STATUS, &val);
+	if (ret < 0)
+		status = connector_status_disconnected;
+	else if (val & ADV7511_STATUS_HPD)
+		status = connector_status_connected;
+	else
+		status = connector_status_disconnected;
+
+	if (adv7511->connector.status != status)
+		drm_kms_helper_hotplug_event(adv7511->connector.dev);
 
-	drm_helper_hpd_irq_event(adv7511->connector.dev);
+	adv7511->connector.status = status;
 }
 
 static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd)
-- 
2.7.4

[RFC][PATCH 2/5 v3] drm/bridge: adv7511: Switch to using drm_kms_helper_hotplug_event()

[John Stultz]

In chasing down a previous issue with EDID probing from calling
drm_helper_hpd_irq_event() from irq context, Laurent noticed
that the DRM documentation suggests that
drm_kms_helper_hotplug_event() should be used instead.

Thus this patch replaces drm_helper_hpd_irq_event() with
drm_kms_helper_hotplug_event(), which requires we update the
connector.status entry and only call _hotplug_event() when the
status changes.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
v3: Update connector.status value and only call __hotplug_event()
    when that status changes, as suggested by Laurent.
---
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index 4fcea44..d93d66f 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -405,8 +405,22 @@ static bool adv7511_hpd(struct adv7511 *adv7511)
 static void adv7511_hpd_work(struct work_struct *work)
 {
 	struct adv7511 *adv7511 = container_of(work, struct adv7511, hpd_work);
+	enum drm_connector_status status;
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(adv7511->regmap, ADV7511_REG_STATUS, &val);
+	if (ret < 0)
+		status = connector_status_disconnected;
+	else if (val & ADV7511_STATUS_HPD)
+		status = connector_status_connected;
+	else
+		status = connector_status_disconnected;
+
+	if (adv7511->connector.status != status)
+		drm_kms_helper_hotplug_event(adv7511->connector.dev);
 
-	drm_helper_hpd_irq_event(adv7511->connector.dev);
+	adv7511->connector.status = status;
 }
 
 static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd)
-- 
2.7.4

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[RFC][PATCH 3/5 v3] drm/bridge: adv7511: Enable HPD interrupts to support hotplug and improve monitor detection

[John Stultz]

From: Archit Taneja <architt@codeaurora.org>

On some adv7511 implementations, we can get some spurious
disconnect signals which can cause monitor probing to fail.

This patch enables HPD (hot plug detect) interrupt support
which allows the monitor to be properly re-initialized when
the spurious disconnect signal goes away.

This also enables proper hotplug support.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Originally-by: Archit Taneja <architt@codeaurora.org>
[jstultz: Added proper commit message]
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index d93d66f..4b90975 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -338,7 +338,7 @@ static void adv7511_power_on(struct adv7511 *adv7511)
 		 * Still, let's be safe and stick to the documentation.
 		 */
 		regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(0),
-			     ADV7511_INT0_EDID_READY);
+			     ADV7511_INT0_EDID_READY | ADV7511_INT0_HPD);
 		regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(1),
 			     ADV7511_INT1_DDC_ERROR);
 	}
@@ -846,6 +846,10 @@ static int adv7511_bridge_attach(struct drm_bridge *bridge)
 	if (adv->type == ADV7533)
 		ret = adv7533_attach_dsi(adv);
 
+	if (adv->i2c_main->irq)
+		regmap_write(adv->regmap, ADV7511_REG_INT_ENABLE(0),
+				ADV7511_INT0_HPD);
+
 	return ret;
 }
 
-- 
2.7.4

[RFC][PATCH 4/5 v3] drm/bridge: adv7511: Rework adv7511_power_on/off() so they can be reused internally

[John Stultz]

In chasing down issues with EDID probing, I found some
duplicated but incomplete logic used to power the chip on and
off.

This patch refactors the adv7511_power_on/off functions, so
they can be used for internal needs.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index 4b90975..dbdb71c 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -325,7 +325,7 @@ static void adv7511_set_link_config(struct adv7511 *adv7511,
 	adv7511->rgb = config->input_colorspace == HDMI_COLORSPACE_RGB;
 }
 
-static void adv7511_power_on(struct adv7511 *adv7511)
+static void __adv7511_power_on(struct adv7511 *adv7511)
 {
 	adv7511->current_edid_segment = -1;
 
@@ -359,24 +359,30 @@ static void adv7511_power_on(struct adv7511 *adv7511)
 	 * Most of the registers are reset during power down or when HPD is low.
 	 */
 	regcache_sync(adv7511->regmap);
+}
 
+static void adv7511_power_on(struct adv7511 *adv7511)
+{
+	__adv7511_power_on(adv7511);
 	if (adv7511->type == ADV7533)
 		adv7533_dsi_power_on(adv7511);
-
 	adv7511->powered = true;
 }
 
-static void adv7511_power_off(struct adv7511 *adv7511)
+static void __adv7511_power_off(struct adv7511 *adv7511)
 {
 	/* TODO: setup additional power down modes */
 	regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
 			   ADV7511_POWER_POWER_DOWN,
 			   ADV7511_POWER_POWER_DOWN);
 	regcache_mark_dirty(adv7511->regmap);
+}
 
+static void adv7511_power_off(struct adv7511 *adv7511)
+{
+	__adv7511_power_off(adv7511);
 	if (adv7511->type == ADV7533)
 		adv7533_dsi_power_off(adv7511);
-
 	adv7511->powered = false;
 }
 
-- 
2.7.4

[RFC][PATCH 4/5 v3] drm/bridge: adv7511: Rework adv7511_power_on/off() so they can be reused internally

[John Stultz]

In chasing down issues with EDID probing, I found some
duplicated but incomplete logic used to power the chip on and
off.

This patch refactors the adv7511_power_on/off functions, so
they can be used for internal needs.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index 4b90975..dbdb71c 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -325,7 +325,7 @@ static void adv7511_set_link_config(struct adv7511 *adv7511,
 	adv7511->rgb = config->input_colorspace == HDMI_COLORSPACE_RGB;
 }
 
-static void adv7511_power_on(struct adv7511 *adv7511)
+static void __adv7511_power_on(struct adv7511 *adv7511)
 {
 	adv7511->current_edid_segment = -1;
 
@@ -359,24 +359,30 @@ static void adv7511_power_on(struct adv7511 *adv7511)
 	 * Most of the registers are reset during power down or when HPD is low.
 	 */
 	regcache_sync(adv7511->regmap);
+}
 
+static void adv7511_power_on(struct adv7511 *adv7511)
+{
+	__adv7511_power_on(adv7511);
 	if (adv7511->type == ADV7533)
 		adv7533_dsi_power_on(adv7511);
-
 	adv7511->powered = true;
 }
 
-static void adv7511_power_off(struct adv7511 *adv7511)
+static void __adv7511_power_off(struct adv7511 *adv7511)
 {
 	/* TODO: setup additional power down modes */
 	regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
 			   ADV7511_POWER_POWER_DOWN,
 			   ADV7511_POWER_POWER_DOWN);
 	regcache_mark_dirty(adv7511->regmap);
+}
 
+static void adv7511_power_off(struct adv7511 *adv7511)
+{
+	__adv7511_power_off(adv7511);
 	if (adv7511->type == ADV7533)
 		adv7533_dsi_power_off(adv7511);
-
 	adv7511->powered = false;
 }
 
-- 
2.7.4

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[RFC][PATCH 5/5 v3] drm/bridge: adv7511: Reuse __adv7511_power_on/off() when probing EDID

[John Stultz]

I've found that by just turning the chip on and off via the
POWER_DOWN register, I end up getting i2c_transfer errors
on HiKey.

Investigating further, it seems some of the register state
in the regmap cache is somehow getting lost. Using the logic
in __adv7511_power_on/off() which syncs and dirtys the cache
avoids this issue.

Thus this patch changes the EDID probing logic so that we
re-use the __adv7511_power_on/off() calls.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index dbdb71c..24573e0 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -572,24 +572,13 @@ static int adv7511_get_modes(struct adv7511 *adv7511,
 	unsigned int count;
 
 	/* Reading the EDID only works if the device is powered */
-	if (!adv7511->powered) {
-		regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
-				   ADV7511_POWER_POWER_DOWN, 0);
-		if (adv7511->i2c_main->irq) {
-			regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(0),
-				     ADV7511_INT0_EDID_READY);
-			regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(1),
-				     ADV7511_INT1_DDC_ERROR);
-		}
-		adv7511->current_edid_segment = -1;
-	}
+	if (!adv7511->powered)
+		__adv7511_power_on(adv7511);
 
 	edid = drm_do_get_edid(connector, adv7511_get_edid_block, adv7511);
 
 	if (!adv7511->powered)
-		regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
-				   ADV7511_POWER_POWER_DOWN,
-				   ADV7511_POWER_POWER_DOWN);
+		__adv7511_power_off(adv7511);
 
 	kfree(adv7511->edid);
 	adv7511->edid = edid;
-- 
2.7.4

[RFC][PATCH 5/5 v3] drm/bridge: adv7511: Reuse __adv7511_power_on/off() when probing EDID

[John Stultz]

I've found that by just turning the chip on and off via the
POWER_DOWN register, I end up getting i2c_transfer errors
on HiKey.

Investigating further, it seems some of the register state
in the regmap cache is somehow getting lost. Using the logic
in __adv7511_power_on/off() which syncs and dirtys the cache
avoids this issue.

Thus this patch changes the EDID probing logic so that we
re-use the __adv7511_power_on/off() calls.

Cc: David Airlie <airlied@linux.ie>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index dbdb71c..24573e0 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -572,24 +572,13 @@ static int adv7511_get_modes(struct adv7511 *adv7511,
 	unsigned int count;
 
 	/* Reading the EDID only works if the device is powered */
-	if (!adv7511->powered) {
-		regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
-				   ADV7511_POWER_POWER_DOWN, 0);
-		if (adv7511->i2c_main->irq) {
-			regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(0),
-				     ADV7511_INT0_EDID_READY);
-			regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(1),
-				     ADV7511_INT1_DDC_ERROR);
-		}
-		adv7511->current_edid_segment = -1;
-	}
+	if (!adv7511->powered)
+		__adv7511_power_on(adv7511);
 
 	edid = drm_do_get_edid(connector, adv7511_get_edid_block, adv7511);
 
 	if (!adv7511->powered)
-		regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
-				   ADV7511_POWER_POWER_DOWN,
-				   ADV7511_POWER_POWER_DOWN);
+		__adv7511_power_off(adv7511);
 
 	kfree(adv7511->edid);
 	adv7511->edid = edid;
-- 
2.7.4

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