[PATCH v2 01/13] drm/msm/dsi: switch to devm_drm_bridge_add()

[Abhinav Kumar]

On 10/9/2023 11:10 AM, Dmitry Baryshkov wrote:
> Make MSM DSI driver use devm_drm_bridge_add() instead of plain
> drm_bridge_add(). As the driver doesn't require any additional cleanup,
> stop adding created bridge to the priv->bridges array.
> 
> Reviewed-by: Rob Clark <robdclark at gmail.com>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
> ---
>   drivers/gpu/drm/msm/dsi/dsi.c         | 28 +++++--------------------
>   drivers/gpu/drm/msm/dsi/dsi.h         |  3 +--
>   drivers/gpu/drm/msm/dsi/dsi_manager.c | 30 +++++++++------------------
>   3 files changed, 16 insertions(+), 45 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dsi/dsi.c b/drivers/gpu/drm/msm/dsi/dsi.c
> index d45e43024802..47f327e68471 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi.c
> @@ -215,20 +215,14 @@ void __exit msm_dsi_unregister(void)
>   int msm_dsi_modeset_init(struct msm_dsi *msm_dsi, struct drm_device *dev,
>   			 struct drm_encoder *encoder)
>   {
> -	struct msm_drm_private *priv = dev->dev_private;
>   	int ret;
>   
> -	if (priv->num_bridges == ARRAY_SIZE(priv->bridges)) {
> -		DRM_DEV_ERROR(dev->dev, "too many bridges\n");
> -		return -ENOSPC;
> -	}
> -
>   	msm_dsi->dev = dev;
>   
>   	ret = msm_dsi_host_modeset_init(msm_dsi->host, dev);
>   	if (ret) {
>   		DRM_DEV_ERROR(dev->dev, "failed to modeset init host: %d\n", ret);
> -		goto fail;
> +		return ret;
>   	}
>   
>   	if (msm_dsi_is_bonded_dsi(msm_dsi) &&
> @@ -242,32 +236,20 @@ int msm_dsi_modeset_init(struct msm_dsi *msm_dsi, struct drm_device *dev,
>   
>   	msm_dsi->encoder = encoder;
>   
> -	msm_dsi->bridge = msm_dsi_manager_bridge_init(msm_dsi->id);
> -	if (IS_ERR(msm_dsi->bridge)) {
> -		ret = PTR_ERR(msm_dsi->bridge);
> +	ret = msm_dsi_manager_bridge_init(msm_dsi);
> +	if (ret) {
>   		DRM_DEV_ERROR(dev->dev, "failed to create dsi bridge: %d\n", ret);
> -		msm_dsi->bridge = NULL;
> -		goto fail;
> +		return ret;
>   	}
>   
>   	ret = msm_dsi_manager_ext_bridge_init(msm_dsi->id);
>   	if (ret) {
>   		DRM_DEV_ERROR(dev->dev,
>   			"failed to create dsi connector: %d\n", ret);
> -		goto fail;
> +		return ret;
>   	}
>   
> -	priv->bridges[priv->num_bridges++]       = msm_dsi->bridge;
> -
>   	return 0;
> -fail:
> -	/* bridge/connector are normally destroyed by drm: */
> -	if (msm_dsi->bridge) {
> -		msm_dsi_manager_bridge_destroy(msm_dsi->bridge);
> -		msm_dsi->bridge = NULL;
> -	}

We can drop msm_dsi_manager_bridge_destroy() now but dont we need to 
keep the part to reset msm_dsi->bridge to NULL in the fail tag if 
msm_dsi_manager_ext_bridge_init() fails?

> -
> -	return ret;
>   }
>   
>   void msm_dsi_snapshot(struct msm_disp_state *disp_state, struct msm_dsi *msm_dsi)
> diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
> index d21867da78b8..a01c326774a6 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi.h
> +++ b/drivers/gpu/drm/msm/dsi/dsi.h
> @@ -56,8 +56,7 @@ struct msm_dsi {
>   };
>   
>   /* dsi manager */
> -struct drm_bridge *msm_dsi_manager_bridge_init(u8 id);
> -void msm_dsi_manager_bridge_destroy(struct drm_bridge *bridge);
> +int msm_dsi_manager_bridge_init(struct msm_dsi *msm_dsi);
>   int msm_dsi_manager_ext_bridge_init(u8 id);
>   int msm_dsi_manager_cmd_xfer(int id, const struct mipi_dsi_msg *msg);
>   bool msm_dsi_manager_cmd_xfer_trigger(int id, u32 dma_base, u32 len);
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> index 28b8012a21f2..17aa19bb6510 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> @@ -466,9 +466,8 @@ static const struct drm_bridge_funcs dsi_mgr_bridge_funcs = {
>   };
>   
>   /* initialize bridge */
> -struct drm_bridge *msm_dsi_manager_bridge_init(u8 id)
> +int msm_dsi_manager_bridge_init(struct msm_dsi *msm_dsi)
>   {
> -	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
>   	struct drm_bridge *bridge = NULL;
>   	struct dsi_bridge *dsi_bridge;
>   	struct drm_encoder *encoder;
> @@ -476,31 +475,27 @@ struct drm_bridge *msm_dsi_manager_bridge_init(u8 id)
>   
>   	dsi_bridge = devm_kzalloc(msm_dsi->dev->dev,
>   				sizeof(*dsi_bridge), GFP_KERNEL);
> -	if (!dsi_bridge) {
> -		ret = -ENOMEM;
> -		goto fail;
> -	}
> +	if (!dsi_bridge)
> +		return -ENOMEM;
>   
> -	dsi_bridge->id = id;
> +	dsi_bridge->id = msm_dsi->id;
>   
>   	encoder = msm_dsi->encoder;
>   
>   	bridge = &dsi_bridge->base;
>   	bridge->funcs = &dsi_mgr_bridge_funcs;
>   
> -	drm_bridge_add(bridge);
> +	ret = devm_drm_bridge_add(&msm_dsi->pdev->dev, bridge);
> +	if (ret)
> +		return ret;
>   
>   	ret = drm_bridge_attach(encoder, bridge, NULL, 0);
>   	if (ret)
> -		goto fail;
> +		return ret;
>   
> -	return bridge;
> +	msm_dsi->bridge = bridge;
>   
> -fail:
> -	if (bridge)
> -		msm_dsi_manager_bridge_destroy(bridge);
> -
> -	return ERR_PTR(ret);
> +	return 0;
>   }
>   
>   int msm_dsi_manager_ext_bridge_init(u8 id)
> @@ -557,11 +552,6 @@ int msm_dsi_manager_ext_bridge_init(u8 id)
>   	return 0;
>   }
>   
> -void msm_dsi_manager_bridge_destroy(struct drm_bridge *bridge)
> -{
> -	drm_bridge_remove(bridge);
> -}
> -
>   int msm_dsi_manager_cmd_xfer(int id, const struct mipi_dsi_msg *msg)
>   {
>   	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);