[PATCH v4 07/13] drm/bridge: analogix_dp: Apply drm_bridge_connector helper

[Damon Ding]

Hi Dmitry,

On 8/29/2025 4:48 PM, Dmitry Baryshkov wrote:
> On Wed, Aug 20, 2025 at 05:18:13PM +0800, Damon Ding wrote:
>> Hi Dmitry,
>>
>> On 8/17/2025 12:43 AM, Dmitry Baryshkov wrote:
>>> On Thu, Aug 14, 2025 at 06:47:47PM +0800, Damon Ding wrote:
>>>> Apply drm_bridge_connector helper for Analogix DP driver.
>>>>
>>>> The following changes have been made:
>>>> - Apply drm_bridge_connector helper to get rid of &drm_connector_funcs
>>>>     and &drm_connector_helper_funcs.
>>>> - Remove unnecessary parameter struct drm_connector* for callback
>>>>     &analogix_dp_plat_data.attach.
>>>> - Remove &analogix_dp_device.connector.
>>>> - Convert analogix_dp_atomic_check()/analogix_dp_detect() to
>>>>     &drm_bridge_funcs.atomic_check()/&drm_bridge_funcs.detect().
>>>> - Split analogix_dp_get_modes() into &drm_bridge_funcs.get_modes() and
>>>>     &drm_bridge_funcs.edid_read().
>>>>
>>>> Signed-off-by: Damon Ding <damon.ding at rock-chips.com>
>>>>
>>>> ------
>>>>
>>>> Changes in v2:
>>>> - For &drm_bridge.ops, remove DRM_BRIDGE_OP_HPD and add
>>>>     DRM_BRIDGE_OP_EDID.
>>>> - Add analogix_dp_bridge_edid_read().
>>>> - Move &analogix_dp_plat_data.skip_connector deletion to the previous
>>>>     patches.
>>>>
>>>> Changes in v3:
>>>> - Rebase with the new devm_drm_bridge_alloc() related commit
>>>>     48f05c3b4b70 ("drm/bridge: analogix_dp: Use devm_drm_bridge_alloc()
>>>>     API").
>>>> - Expand the commit message.
>>>> - Call drm_bridge_get_modes() in analogix_dp_bridge_get_modes() if the
>>>>     bridge is available.
>>>> - Remove unnecessary parameter struct drm_connector* for callback
>>>>     &analogix_dp_plat_data.attach.
>>>> - In order to decouple the connector driver and the bridge driver, move
>>>>     the bridge connector initilization to the Rockchip and Exynos sides.
>>>>
>>>> Changes in v4:
>>>> - Expand analogix_dp_bridge_detect() parameters to &drm_bridge and
>>>>     &drm_connector.
>>>> - Rename the &analogix_dp_plat_data.bridge to
>>>>     &analogix_dp_plat_data.next_bridge.
>>>> ---
>>>>    .../drm/bridge/analogix/analogix_dp_core.c    | 145 ++++++++----------
>>>>    .../drm/bridge/analogix/analogix_dp_core.h    |   1 -
>>>>    drivers/gpu/drm/exynos/exynos_dp.c            |  18 ++-
>>>>    .../gpu/drm/rockchip/analogix_dp-rockchip.c   |  11 +-
>>>>    include/drm/bridge/analogix_dp.h              |   3 +-
>>>>    5 files changed, 88 insertions(+), 90 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>>>> index 7876b310aaed..a8ed44ec8ef5 100644
>>>> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>>>> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
>>>> @@ -947,24 +947,16 @@ static int analogix_dp_disable_psr(struct analogix_dp_device *dp)
>>>>    	return analogix_dp_send_psr_spd(dp, &psr_vsc, true);
>>>>    }
>>>> -static int analogix_dp_get_modes(struct drm_connector *connector)
>>>> +static int analogix_dp_bridge_get_modes(struct drm_bridge *bridge, struct drm_connector *connector)
>>>>    {
>>>> -	struct analogix_dp_device *dp = to_dp(connector);
>>>> -	const struct drm_edid *drm_edid;
>>>> +	struct analogix_dp_device *dp = to_dp(bridge);
>>>>    	int num_modes = 0;
>>>> -	if (dp->plat_data->panel) {
>>>> +	if (dp->plat_data->panel)
>>>>    		num_modes += drm_panel_get_modes(dp->plat_data->panel, connector);
>>>> -	} else {
>>>> -		drm_edid = drm_edid_read_ddc(connector, &dp->aux.ddc);
>>>> -		drm_edid_connector_update(&dp->connector, drm_edid);
>>>> -
>>>> -		if (drm_edid) {
>>>> -			num_modes += drm_edid_connector_add_modes(&dp->connector);
>>>> -			drm_edid_free(drm_edid);
>>>> -		}
>>>> -	}
>>>> +	if (dp->plat_data->next_bridge)
>>>> +		num_modes += drm_bridge_get_modes(dp->plat_data->next_bridge, connector);
>>>
>>> If there is a next bridge which provides OP_MODES, then
>>> drm_bridge_connector will use it for get_modes() and skip this one
>>> completely. I'm not sure what's the value of this call.
>>
>> Following your advice, it is really a good idea to distinguish the
>> drm_bridge_ops between the panel and the bridge. Will add it in v5.
>>
>>>
>>>>    	if (dp->plat_data->get_modes)
>>>>    		num_modes += dp->plat_data->get_modes(dp->plat_data, connector);
>>>> @@ -972,51 +964,39 @@ static int analogix_dp_get_modes(struct drm_connector *connector)
>>>>    	return num_modes;
>>>>    }
>>>> -static struct drm_encoder *
>>>> -analogix_dp_best_encoder(struct drm_connector *connector)
>>>> +static const struct drm_edid *analogix_dp_bridge_edid_read(struct drm_bridge *bridge,
>>>> +							   struct drm_connector *connector)
>>>>    {
>>>> -	struct analogix_dp_device *dp = to_dp(connector);
>>>> +	struct analogix_dp_device *dp = to_dp(bridge);
>>>> +	const struct drm_edid *drm_edid = NULL;
>>>> -	return dp->encoder;
>>>> -}
>>>> +	drm_edid = drm_edid_read_ddc(connector, &dp->aux.ddc);
>>>> +	if (dp->plat_data->get_modes)
>>>> +		dp->plat_data->get_modes(dp->plat_data, connector);
>>>
>>>
>>> So, we have DDC, but we still want to return platform modes? What is the
>>> usecase for that?
>>>
>>> There might be some, but I think it deserves a comment in the source
>>> file.
>>>
>>
>> For Rockchip side, since RK3588 and RK3576 can support YUV formats while the
>> other can not, the &analogix_dp_plat_data.get_modes() help filter out YUV
>> formats for some platforms(The YUV feature support may not be fit for this
>> patch series and will come later).
> 
> Note, get_modes() here adds modes rather than filtering them. You can
> use .mode_valid in order to filter out YUV modes.
> 

Yeah，I will move it to &drm_bridge_funcs.mode_valid() in a new separate 
commit.

>>
>> For Exynos side, I think &analogix_dp_plat_data.get_modes() can help
>> parse the video mode set in the eDP DT node when there is no available panel
>> or bridge.
> 
> I think this should be handled by a separate bridge. E.g. see how the
> imx-legacy-bridge is implemented.
> 

It can make the codes more consistent. Will do in the next version.

>>
>> I will add some comments about it in the next version.
>>
> 

Best regards,
Damon