Re: [PATCH 4/7] drm/exynos/hdmi: add bridge support

[Andrzej Hajda]

On 01.02.2017 08:31, Inki Dae wrote:
>
> 2017ë 01ì 20ì 15:52ì Andrzej Hajda ì(ê) ì ê:
>> In some platforms there is attached another device to the end of HDMI.
>> The patch adds support for it.
> Andrzej, can you clarify what bridge device can be attached and actually is now attached to the end of HDMI?
> And I wonder if we have the device tree file which defines the bridge device in mainline. Seems we have no the device tree file.
>
> If nothing, then this patch should be merged with real use case.

SiI8620 MHL bridge in tm2/tm2e.

Regards
Andrzej

>
> Thanks.
>
>> Signed-off-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
>> ---
>>  drivers/gpu/drm/exynos/exynos_hdmi.c | 56 +++++++++++++++++++++++++++++-------
>>  1 file changed, 46 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
>> index a73b192..41fb894 100644
>> --- a/drivers/gpu/drm/exynos/exynos_hdmi.c
>> +++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
>> @@ -35,6 +35,7 @@
>>  #include <linux/io.h>
>>  #include <linux/of_address.h>
>>  #include <linux/of_device.h>
>> +#include <linux/of_graph.h>
>>  #include <linux/hdmi.h>
>>  #include <linux/component.h>
>>  #include <linux/mfd/syscon.h>
>> @@ -133,6 +134,7 @@ struct hdmi_context {
>>  	struct regulator_bulk_data	regul_bulk[ARRAY_SIZE(supply)];
>>  	struct regulator		*reg_hdmi_en;
>>  	struct exynos_drm_clk		phy_clk;
>> +	struct drm_bridge		*bridge;
>>  };
>>  
>>  static inline struct hdmi_context *encoder_to_hdmi(struct drm_encoder *e)
>> @@ -922,7 +924,15 @@ static int hdmi_create_connector(struct drm_encoder *encoder)
>>  	drm_connector_register(connector);
>>  	drm_mode_connector_attach_encoder(connector, encoder);
>>  
>> -	return 0;
>> +	if (hdata->bridge) {
>> +		encoder->bridge = hdata->bridge;
>> +		hdata->bridge->encoder = encoder;
>> +		ret = drm_bridge_attach(encoder->dev, hdata->bridge);
>> +		if (ret)
>> +			DRM_ERROR("Failed to attach bridge\n");
>> +	}
>> +
>> +	return ret;
>>  }
>>  
>>  static bool hdmi_mode_fixup(struct drm_encoder *encoder,
>> @@ -1591,6 +1601,31 @@ static void hdmiphy_clk_enable(struct exynos_drm_clk *clk, bool enable)
>>  		hdmiphy_disable(hdata);
>>  }
>>  
>> +static int hdmi_bridge_init(struct hdmi_context *hdata)
>> +{
>> +	struct device *dev = hdata->dev;
>> +	struct device_node *ep, *np;
>> +
>> +	ep = of_graph_get_endpoint_by_regs(dev->of_node, 1, -1);
>> +	if (!ep)
>> +		return 0;
>> +
>> +	np = of_graph_get_remote_port_parent(ep);
>> +	of_node_put(ep);
>> +	if (!np) {
>> +		DRM_ERROR("failed to get remote port parent");
>> +		return -EINVAL;
>> +	}
>> +
>> +	hdata->bridge = of_drm_find_bridge(np);
>> +	of_node_put(np);
>> +
>> +	if (!hdata->bridge)
>> +		return -EPROBE_DEFER;
>> +
>> +	return 0;
>> +}
>> +
>>  static int hdmi_resources_init(struct hdmi_context *hdata)
>>  {
>>  	struct device *dev = hdata->dev;
>> @@ -1630,17 +1665,18 @@ static int hdmi_resources_init(struct hdmi_context *hdata)
>>  
>>  	hdata->reg_hdmi_en = devm_regulator_get_optional(dev, "hdmi-en");
>>  
>> -	if (PTR_ERR(hdata->reg_hdmi_en) == -ENODEV)
>> -		return 0;
>> +	if (PTR_ERR(hdata->reg_hdmi_en) != -ENODEV) {
>> +		if (IS_ERR(hdata->reg_hdmi_en))
>> +			return PTR_ERR(hdata->reg_hdmi_en);
>>  
>> -	if (IS_ERR(hdata->reg_hdmi_en))
>> -		return PTR_ERR(hdata->reg_hdmi_en);
>> -
>> -	ret = regulator_enable(hdata->reg_hdmi_en);
>> -	if (ret)
>> -		DRM_ERROR("failed to enable hdmi-en regulator\n");
>> +		ret = regulator_enable(hdata->reg_hdmi_en);
>> +		if (ret) {
>> +			DRM_ERROR("failed to enable hdmi-en regulator\n");
>> +			return ret;
>> +		}
>> +	}
>>  
>> -	return ret;
>> +	return hdmi_bridge_init(hdata);
>>  }
>>  
>>  static struct of_device_id hdmi_match_types[] = {
>>
>