Re: [PATCH 1/4 v3] drm: Rename drm_connector_unplug_all() to drm_connector_unregister_all()

[Boris Brezillon <boris.brezillon@free-electrons.com>]

On Wed, 23 Mar 2016 11:42:54 +0300
Alexey Brodkin <Alexey.Brodkin@synopsys.com> wrote:

> Current name is a bit misleading because what that helper function
> really does it calls drm_connector_unregister() for all connectors.
> 
> This all has nothing to do with hotplugging so let's name things
> properly.
> 
> And while at it remove potentially dangerous locking around
> drm_connector_unregister() in rcar_du_remove() as mentioned
> in kerneldoc for drm_connector_unregister_all().
> 
> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Boris Brezillon <boris.brezillon@free-electrons.com>

Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>

> Cc: linux-renesas-soc@vger.kernel.org
> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> 
> Changes v2 -> v3:
>  * Updated title with capital after colon
>  * Updated kerneldoc description of drm_connector_unregister_all()
>    so that it will match description of register_all() to be introduced
>    in the next change
>  * Added ack from Laurent
> 
> Changes v1 -> v2:
>  * This patch was only introduced in v2.
> 
>  drivers/gpu/drm/drm_crtc.c            | 18 +++++++++---------
>  drivers/gpu/drm/rcar-du/rcar_du_drv.c |  5 +----
>  drivers/gpu/drm/udl/udl_drv.c         |  2 +-
>  include/drm/drm_crtc.h                |  4 ++--
>  4 files changed, 13 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 65258ac..65488a6 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -1080,25 +1080,25 @@ void drm_connector_unregister(struct drm_connector *connector)
>  }
>  EXPORT_SYMBOL(drm_connector_unregister);
>  
> -
>  /**
> - * drm_connector_unplug_all - unregister connector userspace interfaces
> + * drm_connector_unregister_all - unregister connector userspace interfaces
>   * @dev: drm device
>   *
> - * This function unregisters all connector userspace interfaces in sysfs. Should
> - * be call when the device is disconnected, e.g. from an usb driver's
> - * ->disconnect callback.
> + * This functions unregisters all connectors from sysfs and other places so
> + * that userspace can no longer access them. Drivers should call this as the
> + * first step tearing down the device instace, or when the underlying
> + * physical device disappeared (e.g. USB unplug), right before calling
> + * drm_dev_unregister().
>   */
> -void drm_connector_unplug_all(struct drm_device *dev)
> +void drm_connector_unregister_all(struct drm_device *dev)
>  {
>  	struct drm_connector *connector;
>  
>  	/* FIXME: taking the mode config mutex ends up in a clash with sysfs */
> -	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
> +	drm_for_each_connector(connector, dev)
>  		drm_connector_unregister(connector);
> -
>  }
> -EXPORT_SYMBOL(drm_connector_unplug_all);
> +EXPORT_SYMBOL(drm_connector_unregister_all);
>  
>  /**
>   * drm_encoder_init - Init a preallocated encoder
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.c b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> index ed6006b..644db36 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> @@ -278,10 +278,7 @@ static int rcar_du_remove(struct platform_device *pdev)
>  	struct rcar_du_device *rcdu = platform_get_drvdata(pdev);
>  	struct drm_device *ddev = rcdu->ddev;
>  
> -	mutex_lock(&ddev->mode_config.mutex);
> -	drm_connector_unplug_all(ddev);
> -	mutex_unlock(&ddev->mode_config.mutex);
> -
> +	drm_connector_unregister_all(ddev);
>  	drm_dev_unregister(ddev);
>  
>  	if (rcdu->fbdev)
> diff --git a/drivers/gpu/drm/udl/udl_drv.c b/drivers/gpu/drm/udl/udl_drv.c
> index 772ec9e..c204089 100644
> --- a/drivers/gpu/drm/udl/udl_drv.c
> +++ b/drivers/gpu/drm/udl/udl_drv.c
> @@ -94,7 +94,7 @@ static void udl_usb_disconnect(struct usb_interface *interface)
>  	struct drm_device *dev = usb_get_intfdata(interface);
>  
>  	drm_kms_helper_poll_disable(dev);
> -	drm_connector_unplug_all(dev);
> +	drm_connector_unregister_all(dev);
>  	udl_fbdev_unplug(dev);
>  	udl_drop_usb(dev);
>  	drm_unplug_dev(dev);
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 8c7fb3d..42d9f4d 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -2214,8 +2214,8 @@ void drm_connector_unregister(struct drm_connector *connector);
>  
>  extern void drm_connector_cleanup(struct drm_connector *connector);
>  extern unsigned int drm_connector_index(struct drm_connector *connector);
> -/* helper to unplug all connectors from sysfs for device */
> -extern void drm_connector_unplug_all(struct drm_device *dev);
> +/* helper to unregister all connectors from sysfs for device */
> +extern void drm_connector_unregister_all(struct drm_device *dev);
>  
>  extern int drm_bridge_add(struct drm_bridge *bridge);
>  extern void drm_bridge_remove(struct drm_bridge *bridge);



-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com