Subject: [PATCH v10 14/17] drm: bridge: analogix/dp: try force hpd after plug in lookup failed

From: [email-masked] (Yakir Yang)
Date: Wed, 9 Dec 2015 09:21:02 +0800

Hi Rob,

Thanks for your respond.

On 12/08/2015 11:09 PM, Rob Herring wrote:
> On Mon, Dec 07, 2015 at 02:40:42PM +0800, Yakir Yang wrote:
>> Some edp screen do not have hpd signal, so we can't just return
>> failed when hpd plug in detect failed.
>>
>> This is an hardware property, so we need add a devicetree property
>> "analogix,need-force-hpd" to indicate this sutiation.
> I can see this being common. Just make it "force-hpd".

Okay, I would send the v10.1 out.

- Yakir

> Rob
>
>> Signed-off-by: Yakir Yang <[email-masked]>
>> Tested-by: Javier Martinez Canillas <[email-masked]>
>> ---
>> Changes in v10: None
>> Changes in v9: None
>> Changes in v8: None
>> Changes in v7: None
>> Changes in v6: None
>> Changes in v5: None
>> Changes in v4: None
>> Changes in v3:
>> - Add "analogix,need-force-hpd" to indicate whether driver need foce
>>    hpd when hpd detect failed.
>>
>> Changes in v2: None
>>
>>   .../bindings/display/bridge/analogix_dp.txt        |  4 ++-
>>   .../bindings/display/exynos/exynos_dp.txt          |  1 +
>>   .../display/rockchip/analogix_dp-rockchip.txt      |  1 +
>>   drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 36 +++++++++++++++++++---
>>   drivers/gpu/drm/bridge/analogix/analogix_dp_core.h |  2 ++
>>   drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c  |  9 ++++++
>>   6 files changed, 47 insertions(+), 6 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/display/bridge/analogix_dp.txt b/Documentation/devicetree/bindings/display/bridge/analogix_dp.txt
>> index 7659a7a..74f0e80 100644
>> --- a/Documentation/devicetree/bindings/display/bridge/analogix_dp.txt
>> +++ b/Documentation/devicetree/bindings/display/bridge/analogix_dp.txt
>> @@ -22,6 +22,9 @@ Required properties for dp-controller:
>>   		from general PHY binding: Should be "dp".
>>   
>>   Optional properties for dp-controller:
>> +	-analogix,need-force-hpd:
>> +		Indicate driver need force hpd when hpd detect failed, this
>> +		is used for some eDP screen which don't have hpd signal.
>>   	-hpd-gpios:
>>   		Hotplug detect GPIO.
>>   		Indicates which GPIO should be used for hotplug detection
>> @@ -31,7 +34,6 @@ Optional properties for dp-controller:
>>   		* Documentation/devicetree/bindings/display/exynos/exynos_dp.txt
>>   		* Documentation/devicetree/bindings/video/analogix_dp-rockchip.txt
>>   
>> -
>>   [1]: Documentation/devicetree/bindings/media/video-interfaces.txt
>>   -------------------------------------------------------------------------------
>>   
>> diff --git a/Documentation/devicetree/bindings/display/exynos/exynos_dp.txt b/Documentation/devicetree/bindings/display/exynos/exynos_dp.txt
>> index 9905081..8800164 100644
>> --- a/Documentation/devicetree/bindings/display/exynos/exynos_dp.txt
>> +++ b/Documentation/devicetree/bindings/display/exynos/exynos_dp.txt
>> @@ -41,6 +41,7 @@ For the below properties, please refer to Analogix DP binding document:
>>   	-phys (required)
>>   	-phy-names (required)
>>   	-hpd-gpios (optional)
>> +	-analogix,need-force-hpd (optional)
>>   	-video interfaces (optional)
>>   
>>   Deprecated properties for DisplayPort:
>> diff --git a/Documentation/devicetree/bindings/display/rockchip/analogix_dp-rockchip.txt b/Documentation/devicetree/bindings/display/rockchip/analogix_dp-rockchip.txt
>> index dae86c4..1f1e594 100644
>> --- a/Documentation/devicetree/bindings/display/rockchip/analogix_dp-rockchip.txt
>> +++ b/Documentation/devicetree/bindings/display/rockchip/analogix_dp-rockchip.txt
>> @@ -32,6 +32,7 @@ For the below properties, please refer to Analogix DP binding document:
>>   - phys (required)
>>   - phy-names (required)
>>   - hpd-gpios (optional)
>> +- analogix,need-force-hpd (optional)
>>   -------------------------------------------------------------------------------
>>   
>>   Example:
>> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>> index a11504b..94968e4 100644
>> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>> @@ -59,15 +59,38 @@ static int analogix_dp_detect_hpd(struct analogix_dp_device *dp)
>>   {
>>   	int timeout_loop = 0;
>>   
>> -	while (analogix_dp_get_plug_in_status(dp) != 0) {
>> +	while (timeout_loop < DP_TIMEOUT_LOOP_COUNT) {
>> +		if (analogix_dp_get_plug_in_status(dp) == 0)
>> +			return 0;
>> +
>>   		timeout_loop++;
>> -		if (timeout_loop > DP_TIMEOUT_LOOP_COUNT) {
>> -			dev_err(dp->dev, "failed to get hpd plug status\n");
>> -			return -ETIMEDOUT;
>> -		}
>>   		usleep_range(10, 11);
>>   	}
>>   
>> +	/*
>> +	 * Some edp screen do not have hpd signal, so we can't just
>> +	 * return failed when hpd plug in detect failed, DT property
>> +	 * "need-force-hpd" would indicate whether driver need this.
>> +	 */
>> +	if (!dp->need_force_hpd)
>> +		return -ETIMEDOUT;
>> +
>> +	/*
>> +	 * The eDP TRM indicate that if HPD_STATUS(RO) is 0, AUX CH
>> +	 * will not work, so we need to give a force hpd action to
>> +	 * set HPD_STATUS manually.
>> +	 */
>> +	dev_dbg(dp->dev, "failed to get hpd plug status, try to force hpd\n");
>> +
>> +	analogix_dp_force_hpd(dp);
>> +
>> +	if (analogix_dp_get_plug_in_status(dp) != 0) {
>> +		dev_err(dp->dev, "failed to get hpd plug in status\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	dev_dbg(dp->dev, "success to get plug in status after force hpd\n");
>> +
>>   	return 0;
>>   }
>>   
>> @@ -1246,6 +1269,9 @@ int analogix_dp_bind(struct device *dev, struct drm_device *drm_dev,
>>   	if (IS_ERR(dp->reg_base))
>>   		return PTR_ERR(dp->reg_base);
>>   
>> +	dp->need_force_hpd =
>> +		of_property_read_bool(dev->of_node, "analogix,need-force-hpd");
>> +
>>   	dp->hpd_gpio = of_get_named_gpio(dev->of_node, "hpd-gpios", 0);
>>   	if (!gpio_is_valid(dp->hpd_gpio))
>>   		dp->hpd_gpio = of_get_named_gpio(dev->of_node,
>> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
>> index e6f8243..d3c7e0a 100644
>> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
>> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
>> @@ -160,6 +160,7 @@ struct analogix_dp_device {
>>   	struct phy		*phy;
>>   	int			dpms_mode;
>>   	int			hpd_gpio;
>> +	bool                    need_force_hpd;
>>   
>>   	struct analogix_dp_plat_data *plat_data;
>>   };
>> @@ -180,6 +181,7 @@ void analogix_dp_set_analog_power_down(struct analogix_dp_device *dp,
>>   				       bool enable);
>>   void analogix_dp_init_analog_func(struct analogix_dp_device *dp);
>>   void analogix_dp_init_hpd(struct analogix_dp_device *dp);
>> +void analogix_dp_force_hpd(struct analogix_dp_device *dp);
>>   enum dp_irq_type analogix_dp_get_irq_type(struct analogix_dp_device *dp);
>>   void analogix_dp_clear_hotplug_interrupts(struct analogix_dp_device *dp);
>>   void analogix_dp_reset_aux(struct analogix_dp_device *dp);
>> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
>> index 21a3287..c7e2959 100644
>> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
>> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
>> @@ -365,6 +365,15 @@ void analogix_dp_init_hpd(struct analogix_dp_device *dp)
>>   	writel(reg, dp->reg_base + ANALOGIX_DP_SYS_CTL_3);
>>   }
>>   
>> +void analogix_dp_force_hpd(struct analogix_dp_device *dp)
>> +{
>> +	u32 reg;
>> +
>> +	reg = readl(dp->reg_base + ANALOGIX_DP_SYS_CTL_3);
>> +	reg = (F_HPD | HPD_CTRL);
>> +	writel(reg, dp->reg_base + ANALOGIX_DP_SYS_CTL_3);
>> +}
>> +
>>   enum dp_irq_type analogix_dp_get_irq_type(struct analogix_dp_device *dp)
>>   {
>>   	u32 reg;
>> -- 
>> 1.9.1
>>
>>
>
>