Re: [PATCH v4 03/16] drm: bridge: analogix/dp: split exynos dp driver to bridge dir

From: Krzysztof Kozlowski
Date: Sun Sep 06 2015 - 20:23:37 EST


On 06.09.2015 16:49, Yakir Yang wrote:
> Hi Krzysztof,
>
> å 09/04/2015 08:41 AM, Krzysztof Kozlowski åé:
>> On 03.09.2015 14:30, Yakir Yang wrote:
>>> Hi Krzysztof,
>>>
>>> å 09/03/2015 08:58 AM, Krzysztof Kozlowski åé:
>>>> On 01.09.2015 14:49, Yakir Yang wrote:
>>>>> Split the dp core driver from exynos directory to bridge
>>>>> directory, and rename the core driver to analogix_dp_*,
>>>>> leave the platform code to analogix_dp-exynos.
>>>>>
>>>>> Signed-off-by: Yakir Yang <ykk@xxxxxxxxxxxxxx>
>>>>> ---
>>>>> Changes in v4:
>>>>> - Take Rob suggest, update "analogix,hpd-gpios" to "hpd-gpios" DT
>>>>> propery.
>>>>> - Take Jingoo suggest, rename "analogix_dp-exynos.c" file name to
>>>>> "exynos_dp.c"
>>>>> - Take Archit suggest, create a separate folder for analogix code in
>>>>> bridge/
>>>>>
>>>>> Changes in v3:
>>>>> - Take Thierry Reding suggest, move exynos's video_timing code
>>>>> to analogix_dp-exynos platform driver, add get_modes method
>>>>> to struct analogix_dp_plat_data.
>>>>> - Take Heiko suggest, rename some "samsung*" dts propery to
>>>>> "analogix*".
>>>>>
>>>>> Changes in v2:
>>>>> - Take Jingoo Han suggest, remove new copyright
>>>>> - Fix compiled failed dut to analogix_dp_device misspell
>
> [.....]
>
>>>>> -static int exynos_dp_bridge_attach(struct drm_bridge *bridge)
>>>>> +static int analogix_dp_bridge_attach(struct drm_bridge *bridge)
>>>>> {
>>>>> - struct exynos_dp_device *dp = bridge->driver_private;
>>>>> - struct drm_encoder *encoder = &dp->encoder;
>>>>> + struct analogix_dp_device *dp = bridge->driver_private;
>>>>> + struct drm_encoder *encoder = dp->encoder;
>>>>> struct drm_connector *connector = &dp->connector;
>>>>> int ret;
>>>>> - /* Pre-empt DP connector creation if there's a bridge */
>>>>> - if (dp->ptn_bridge) {
>>>>> - ret = exynos_drm_attach_lcd_bridge(dp, encoder);
>>>>> - if (!ret)
>>>>> - return 0;
>>>>> + if (!bridge->encoder) {
>>>>> + DRM_ERROR("Parent encoder object not found");
>>>>> + return -ENODEV;
>>>>> }
>>>>> + encoder->bridge = bridge;
>>>>> +
>>>>> connector->polled = DRM_CONNECTOR_POLL_HPD;
>>>>> ret = drm_connector_init(dp->drm_dev, connector,
>>>>> - &exynos_dp_connector_funcs,
>>>>> + &analogix_dp_connector_funcs,
>>>>> DRM_MODE_CONNECTOR_eDP);
>>>>> if (ret) {
>>>>> DRM_ERROR("Failed to initialize connector with drm\n");
>>>>> return ret;
>>>>> }
>>>>> - drm_connector_helper_add(connector,
>>>>> &exynos_dp_connector_helper_funcs);
>>>>> + drm_connector_helper_add(connector,
>>>>> + &analogix_dp_connector_helper_funcs);
>>>>> drm_connector_register(connector);
>>>>> drm_mode_connector_attach_encoder(connector, encoder);
>>>>> - if (dp->panel)
>>>>> - ret = drm_panel_attach(dp->panel, &dp->connector);
>>>>> + if (dp->plat_data && dp->plat_data->panel) {
>>>>> + ret = drm_panel_attach(dp->plat_data->panel, &dp->connector);
>>>>> + if (ret) {
>>>>> + DRM_ERROR("Failed to attach panel\n");
>>>>> + return ret;
>>>>> + }
>>>>> + }
>>>>> +
>>>>> + /*
>>>>> + * This should be the end of attach function, caused
>>>>> + * we should ensure dp bridge could attach first.
>>>>> + */
>>>>> + if (dp->plat_data && dp->plat_data->attach) {
>>>>> + ret = dp->plat_data->attach(dp->plat_data, bridge);
>>>>> + if (ret) {
>>>>> + DRM_ERROR("Failed at platform attch func\n");
>>>> Two new error paths appeared here and above. Don't you have to
>>>> cleanup something? I don't know, just wondering...
>>> Hmm... I think both panel & platform_attch need ERROR remind when
>>> it failed. But if it still need clean, I though it should clean the
>>> platform attch
>>> error,
>>> this is not relate to DRM directly, just analogix driver logic, so
>>> code would like,
>>>
>>> - if (dp->panel)
>>> - ret = drm_panel_attach(dp->panel, &dp->connector);
>>> + if (dp->plat_data && dp->plat_data->panel) {
>>> + ret = drm_panel_attach(dp->plat_data->panel, &dp->connector);
>>> + if (ret) {
>>> + DRM_ERROR("Failed to attach panel\n");
>>> + return ret;
>>> + }
>>> + }
>>>
>>> + /*
>>> + * This should be the end of attach function, caused
>>> + * we should ensure dp bridge could attach first.
>>> + */
>>> + if (dp->plat_data && dp->plat_data->attach) {
>>> + ret = dp->plat_data->attach(dp->plat_data, bridge);
>>>
>>> return ret;
>> I am lost... the code looks the same. What did you change?
>
> I just remove the DRM_ERROR after dp->plat_data->attach(),
> maybe I should paste the change that rebase on this patch,
> here are they,
>
> /*
> * This should be the end of attach function, caused
> * we should ensure dp bridge could attach first.
> */
> - if (dp->plat_data && dp->plat_data->attach) {
> + if (dp->plat_data && dp->plat_data->attach)
> ret = dp->plat_data->attach(dp->plat_data, bridge);
> - if (ret) {
> - DRM_ERROR("Failed at platform attch func\n");
> - return ret;
> - }
> - }
>
> - return 0;
> + return ret;
>
>
> If this haven't meet your comment, I maybe start to think that
> your comment "Two new error paths appeared here and above"
> indicated that those two function is the same.
> "dp->plat_data->attach(dp->plat_data, bridge); "
> "drm_panel_attach(dp->plat_data->panel, &dp->connector); "

I wasn't talking about error message but rather about possible need of
clean up in error path. Previously there was only drm_panel_attach().
Now you have two of them (drm_panel_attach() and
dp->plat_data->attach()). If the second fails don't you have to clean up
before exit? I don't know, just asking.

Best regards,
Krzysztof

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