[PATCH 1/5] drm/tegra: Store parent pointer in Tegra DRM clients

[Dmitry Osipenko]

23.01.2019 12:39, Thierry Reding пишет:
> From: Thierry Reding <treding at nvidia.com>
> 
> Tegra DRM clients need access to their parent, so store a pointer to it
> upon registration.
> 
> Signed-off-by: Thierry Reding <treding at nvidia.com>
> ---
>  drivers/gpu/drm/tegra/drm.c | 2 ++
>  drivers/gpu/drm/tegra/drm.h | 1 +
>  2 files changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
> index 4b70ce664c41..61dcbd218ffc 100644
> --- a/drivers/gpu/drm/tegra/drm.c
> +++ b/drivers/gpu/drm/tegra/drm.c
> @@ -1041,6 +1041,7 @@ int tegra_drm_register_client(struct tegra_drm *tegra,
>  {
>  	mutex_lock(&tegra->clients_lock);
>  	list_add_tail(&client->list, &tegra->clients);
> +	client->drm = tegra;
>  	mutex_unlock(&tegra->clients_lock);
>  
>  	return 0;
> @@ -1051,6 +1052,7 @@ int tegra_drm_unregister_client(struct tegra_drm *tegra,
>  {
>  	mutex_lock(&tegra->clients_lock);
>  	list_del_init(&client->list);
> +	client->drm = NULL;
>  	mutex_unlock(&tegra->clients_lock);
>  
>  	return 0;
> diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
> index f1763b4d5b5f..2c809755bca7 100644
> --- a/drivers/gpu/drm/tegra/drm.h
> +++ b/drivers/gpu/drm/tegra/drm.h
> @@ -88,6 +88,7 @@ int tegra_drm_submit(struct tegra_drm_context *context,
>  struct tegra_drm_client {
>  	struct host1x_client base;
>  	struct list_head list;
> +	struct tegra_drm *drm;
>  
>  	unsigned int version;
>  	const struct tegra_drm_client_ops *ops;
> 

There is no problem with retrieving of the parent from the clients base structure, hence either this patch could be dropped or please mention in the commit message that the "drm" pointer duplication is solely for helping with keeping code cleaner.