Re: [Intel-gfx] [PATCH 1/8] drm/connector: Give connector sysfs devices there own device_type

[Lyude Paul <lyude@redhat.com>]

On Tue, 2021-08-17 at 23:51 +0200, Hans de Goede wrote:
> Give connector sysfs devices there own device_type, this allows us to
> check if a device passed to functions dealing with generic devices is
> a drm_connector or not.
> 
> A check like this is necessary in the drm_connector_acpi_bus_match()
> function added in the next patch in this series.
> 
> Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/gpu/drm/drm_sysfs.c | 50 +++++++++++++++++++++++++++----------
>  1 file changed, 37 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
> index 968a9560b4aa..f9d92bbb1f98 100644
> --- a/drivers/gpu/drm/drm_sysfs.c
> +++ b/drivers/gpu/drm/drm_sysfs.c
> @@ -50,6 +50,10 @@ static struct device_type drm_sysfs_device_minor = {
>         .name = "drm_minor"
>  };
>  
> +static struct device_type drm_sysfs_device_connector = {
> +       .name = "drm_connector",
> +};
> +
>  struct class *drm_class;
>  
>  static char *drm_devnode(struct device *dev, umode_t *mode)
> @@ -102,6 +106,11 @@ void drm_sysfs_destroy(void)
>         drm_class = NULL;
>  }
>  
> +static void drm_sysfs_release(struct device *dev)
> +{
> +       kfree(dev);
> +}
> +
>  /*
>   * Connector properties
>   */
> @@ -273,27 +282,47 @@ static const struct attribute_group
> *connector_dev_groups[] = {
>  int drm_sysfs_connector_add(struct drm_connector *connector)
>  {
>         struct drm_device *dev = connector->dev;
> +       struct device *kdev;
> +       int r;
>  
>         if (connector->kdev)
>                 return 0;
>  
> -       connector->kdev =
> -               device_create_with_groups(drm_class, dev->primary->kdev, 0,
> -                                         connector, connector_dev_groups,
> -                                         "card%d-%s", dev->primary->index,
> -                                         connector->name);
> +       kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
> +       if (!kdev)
> +               return -ENOMEM;
> +
> +       device_initialize(kdev);
> +       kdev->class = drm_class;
> +       kdev->type = &drm_sysfs_device_connector;
> +       kdev->parent = dev->primary->kdev;
> +       kdev->groups = connector_dev_groups;
> +       kdev->release = drm_sysfs_release;
> +       dev_set_drvdata(kdev, connector);
> +
> +       r = dev_set_name(kdev, "card%d-%s", dev->primary->index, connector-
> >name);
> +       if (r)
> +               goto err_free;
> +
>         DRM_DEBUG("adding \"%s\" to sysfs\n",
>                   connector->name);
>  
> -       if (IS_ERR(connector->kdev)) {
> -               DRM_ERROR("failed to register connector device: %ld\n",
> PTR_ERR(connector->kdev));
> -               return PTR_ERR(connector->kdev);
> +       r = device_add(kdev);
> +       if (r) {
> +               DRM_ERROR("failed to register connector device: %d\n", r);
> +               goto err_free;

Should probably be using drm_err() here since we have access to struct
drm_device *

>         }
>  
> +       connector->kdev = kdev;
> +
>         if (connector->ddc)
>                 return sysfs_create_link(&connector->kdev->kobj,
>                                  &connector->ddc->dev.kobj, "ddc");
>         return 0;
> +
> +err_free:
> +       put_device(kdev);
> +       return r;
>  }
>  
>  void drm_sysfs_connector_remove(struct drm_connector *connector)
> @@ -374,11 +403,6 @@ void drm_sysfs_connector_status_event(struct
> drm_connector *connector,
>  }
>  EXPORT_SYMBOL(drm_sysfs_connector_status_event);
>  
> -static void drm_sysfs_release(struct device *dev)
> -{
> -       kfree(dev);
> -}
> -
>  struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
>  {
>         const char *minor_str;

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat