Re: [PATCH v4 5/7] drm/msm/dp: Support up to 3 DP controllers

[Stephen Boyd <swboyd@chromium.org>]

Quoting Bjorn Andersson (2021-10-05 16:13:21)
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index bdaf227f05dc..674cddfee5b0 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -79,6 +79,8 @@ struct dp_display_private {
>         char *name;
>         int irq;
>
> +       unsigned int id;
> +
>         /* state variables */
>         bool core_initialized;
>         bool hpd_irq_on;
> @@ -229,7 +231,7 @@ static int dp_display_bind(struct device *dev, struct device *master,
>
>         dp->dp_display.drm_dev = drm;
>         priv = drm->dev_private;
> -       priv->dp = &(dp->dp_display);
> +       priv->dp[dp->id] = &(dp->dp_display);

Can we drop the extra parenthesis?

>
>         rc = dp->parser->parse(dp->parser, dp->dp_display.connector_type);
>         if (rc) {
> @@ -269,7 +271,7 @@ static void dp_display_unbind(struct device *dev, struct device *master,
>
>         dp_power_client_deinit(dp->power);
>         dp_aux_unregister(dp->aux);
> -       priv->dp = NULL;
> +       priv->dp[dp->id] = NULL;
>  }
>
>  static const struct component_ops dp_display_comp_ops = {
> @@ -1233,7 +1239,7 @@ static int dp_display_probe(struct platform_device *pdev)
>         if (!dp)
>                 return -ENOMEM;
>
> -       desc = dp_display_get_desc(pdev);
> +       desc = dp_display_get_desc(pdev, &dp->id);

I'm sad that dp->id has to match the number in the SoC specific
dpu_intf_cfg array in drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c
still. Is there any way we can avoid that? Also, notice how those arrays
already have INTF_DP macros, which makes me think that it may be better
to connect this to those arrays instead of making an msm_dp_desc
structure and then make sure the 'type' member matches a connector
type number. Otherwise this code is super fragile.

>         if (!desc)
>                 return -EINVAL;
>