Re: [PATCH v1 4/5] drm/msm/dp: move relevant dp initialization code from bind() to probe()

[Kuogee Hsieh <quic_khsieh@quicinc.com>]

On 7/10/2023 11:13 AM, Dmitry Baryshkov wrote:
> On 10/07/2023 19:57, Kuogee Hsieh wrote:
>>
>> On 7/7/2023 5:11 PM, Dmitry Baryshkov wrote:
>>> On 08/07/2023 02:52, Kuogee Hsieh wrote:
>>>> In preparation of moving edp of_dp_aux_populate_bus() to
>>>> dp_display_probe(), move dp_display_request_irq(),
>>>> dp->parser->parse() and dp_power_client_init() to dp_display_probe()
>>>> too.
>>>>
>>>> Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
>>>> ---
>>>>   drivers/gpu/drm/msm/dp/dp_display.c | 48 
>>>> +++++++++++++++++--------------------
>>>>   drivers/gpu/drm/msm/dp/dp_display.h |  1 -
>>>>   2 files changed, 22 insertions(+), 27 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c 
>>>> b/drivers/gpu/drm/msm/dp/dp_display.c
>>>> index 44580c2..185f1eb 100644
>>>> --- a/drivers/gpu/drm/msm/dp/dp_display.c
>>>> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
>>>> @@ -290,12 +290,6 @@ static int dp_display_bind(struct device *dev, 
>>>> struct device *master,
>>>>           goto end;
>>>>       }
>>>>   -    rc = dp_power_client_init(dp->power);
>>>> -    if (rc) {
>>>> -        DRM_ERROR("Power client create failed\n");
>>>> -        goto end;
>>>> -    }
>>>> -
>>>>       rc = dp_register_audio_driver(dev, dp->audio);
>>>>       if (rc) {
>>>>           DRM_ERROR("Audio registration Dp failed\n");
>>>> @@ -752,6 +746,12 @@ static int dp_init_sub_modules(struct 
>>>> dp_display_private *dp)
>>>>           goto error;
>>>>       }
>>>>   +    rc = dp->parser->parse(dp->parser);
>>>> +    if (rc) {
>>>> +        DRM_ERROR("device tree parsing failed\n");
>>>> +        goto error;
>>>> +    }
>>>> +
>>>>       dp->catalog = dp_catalog_get(dev, &dp->parser->io);
>>>>       if (IS_ERR(dp->catalog)) {
>>>>           rc = PTR_ERR(dp->catalog);
>>>> @@ -768,6 +768,12 @@ static int dp_init_sub_modules(struct 
>>>> dp_display_private *dp)
>>>>           goto error;
>>>>       }
>>>>   +    rc = dp_power_client_init(dp->power);
>>>> +    if (rc) {
>>>> +        DRM_ERROR("Power client create failed\n");
>>>> +        goto error;
>>>> +    }
>>>> +
>>>>       dp->aux = dp_aux_get(dev, dp->catalog, dp->dp_display.is_edp);
>>>>       if (IS_ERR(dp->aux)) {
>>>>           rc = PTR_ERR(dp->aux);
>>>> @@ -1196,26 +1202,20 @@ static irqreturn_t 
>>>> dp_display_irq_handler(int irq, void *dev_id)
>>>>       return ret;
>>>>   }
>>>>   -int dp_display_request_irq(struct msm_dp *dp_display)
>>>> +static int dp_display_request_irq(struct dp_display_private *dp)
>>>>   {
>>>>       int rc = 0;
>>>> -    struct dp_display_private *dp;
>>>> -
>>>> -    if (!dp_display) {
>>>> -        DRM_ERROR("invalid input\n");
>>>> -        return -EINVAL;
>>>> -    }
>>>> -
>>>> -    dp = container_of(dp_display, struct dp_display_private, 
>>>> dp_display);
>>>> +    struct device *dev = &dp->pdev->dev;
>>>>   -    dp->irq = irq_of_parse_and_map(dp->pdev->dev.of_node, 0);
>>>>       if (!dp->irq) {
>>>> -        DRM_ERROR("failed to get irq\n");
>>>> -        return -EINVAL;
>>>> +        dp->irq = irq_of_parse_and_map(dp->pdev->dev.of_node, 0);
>>>> +        if (!dp->irq) {
>>>> +            DRM_ERROR("failed to get irq\n");
>>>> +            return -EINVAL;
>>>> +        }
>>>>       }
>>>
>>> Use platform_get_irq() from probe() function.
>>>
>>>>   -    rc = devm_request_irq(dp_display->drm_dev->dev, dp->irq,
>>>> -            dp_display_irq_handler,
>>>> +    rc = devm_request_irq(dev, dp->irq, dp_display_irq_handler,
>>>>               IRQF_TRIGGER_HIGH, "dp_display_isr", dp);
>>>
>>>
>>>>       if (rc < 0) {
>>>>           DRM_ERROR("failed to request IRQ%u: %d\n",
>>>> @@ -1290,6 +1290,8 @@ static int dp_display_probe(struct 
>>>> platform_device *pdev)
>>>>         platform_set_drvdata(pdev, &dp->dp_display);
>>>>   +    dp_display_request_irq(dp);
>>>> +
>>>
>>> Error checking?
>>> Are we completely ready to handle interrupts at this point?
>> not until dp_display_host_init() is called which will be called from 
>> pm_runtime_resume() later.
>
> But once you request_irq(), you should be ready for the IRQs to be 
> delivered right away.

At this point, the DP controller interrupts mask bit is not enabled yet.

Therefore interrupts will not happen until dp_bridge_hpd_enable() is 
called to initialize dp host  controller and then enabled mask bits.

>
>>>
>>>>       rc = component_add(&pdev->dev, &dp_display_comp_ops);
>>>>       if (rc) {
>>>>           DRM_ERROR("component add failed, rc=%d\n", rc);
>>>> @@ -1574,12 +1576,6 @@ int msm_dp_modeset_init(struct msm_dp 
>>>> *dp_display, struct drm_device *dev,
>>>>         dp_priv = container_of(dp_display, struct 
>>>> dp_display_private, dp_display);
>>>>   -    ret = dp_display_request_irq(dp_display);
>>>> -    if (ret) {
>>>> -        DRM_ERROR("request_irq failed, ret=%d\n", ret);
>>>> -        return ret;
>>>> -    }
>>>> -
>>>>       ret = dp_display_get_next_bridge(dp_display);
>>>>       if (ret)
>>>>           return ret;
>>>> diff --git a/drivers/gpu/drm/msm/dp/dp_display.h 
>>>> b/drivers/gpu/drm/msm/dp/dp_display.h
>>>> index 1e9415a..b3c08de 100644
>>>> --- a/drivers/gpu/drm/msm/dp/dp_display.h
>>>> +++ b/drivers/gpu/drm/msm/dp/dp_display.h
>>>> @@ -35,7 +35,6 @@ struct msm_dp {
>>>>   int dp_display_set_plugged_cb(struct msm_dp *dp_display,
>>>>           hdmi_codec_plugged_cb fn, struct device *codec_dev);
>>>>   int dp_display_get_modes(struct msm_dp *dp_display);
>>>> -int dp_display_request_irq(struct msm_dp *dp_display);
>>>>   bool dp_display_check_video_test(struct msm_dp *dp_display);
>>>>   int dp_display_get_test_bpp(struct msm_dp *dp_display);
>>>>   void dp_display_signal_audio_start(struct msm_dp *dp_display);
>>>
>