diff options
author | Andrea Merello <andrea.merello@gmail.com> | 2016-08-25 11:04:32 +0200 |
---|---|---|
committer | Archit Taneja <architt@codeaurora.org> | 2016-08-29 09:13:00 +0530 |
commit | cf3bef95e1014233cb1ce89da8cfa5cd22e7412c (patch) | |
tree | aa79bd6123a9669499178ee470ec3bd333b486bd | |
parent | 6dcf0de7ef10244b17442f47956a1d9fabe2abe1 (diff) | |
download | linux-cf3bef95e1014233cb1ce89da8cfa5cd22e7412c.tar.bz2 |
drm/bridge: introduce bridge detaching mechanism
Up to now, once a bridge has been attached to a DRM device, it cannot
be undone.
In particular you couldn't rmmod/insmod a DRM driver that uses a bridge,
because the bridge would remain bound to the first (dead) driver instance.
This patch fixes this by introducing drm_encoder_detach() and a ->detach
callback in drm_bridge_funcs for the bridge to be notified about detaches.
It's DRM/KMS driver responsibility to call drm_encoder_detach().
While adding the bridge detach callback, with its kerneldoc, I also added
kerneldoc for attach callback.
Few other kerneldocs fixes around there are included.
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Suggested-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1472115874-6219-1-git-send-email-andrea.merello@gmail.com
-rw-r--r-- | drivers/gpu/drm/drm_bridge.c | 29 | ||||
-rw-r--r-- | include/drm/drm_crtc.h | 26 |
2 files changed, 52 insertions, 3 deletions
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 255543086590..484046664d6c 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -98,11 +98,11 @@ EXPORT_SYMBOL(drm_bridge_remove); * @dev: DRM device * @bridge: bridge control structure * - * called by a kms driver to link one of our encoder/bridge to the given + * Called by a kms driver to link one of our encoder/bridge to the given * bridge. * * Note that setting up links between the bridge and our encoder/bridge - * objects needs to be handled by the kms driver itself + * objects needs to be handled by the kms driver itself. * * RETURNS: * Zero on success, error code on failure @@ -125,6 +125,31 @@ int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge) EXPORT_SYMBOL(drm_bridge_attach); /** + * drm_bridge_detach - deassociate given bridge from its DRM device + * + * @bridge: bridge control structure + * + * Called by a kms driver to unlink the given bridge from its DRM device. + * + * Note that tearing down links between the bridge and our encoder/bridge + * objects needs to be handled by the kms driver itself. + */ +void drm_bridge_detach(struct drm_bridge *bridge) +{ + if (WARN_ON(!bridge)) + return; + + if (WARN_ON(!bridge->dev)) + return; + + if (bridge->funcs->detach) + bridge->funcs->detach(bridge); + + bridge->dev = NULL; +} +EXPORT_SYMBOL(drm_bridge_detach); + +/** * DOC: bridge callbacks * * The &drm_bridge_funcs ops are populated by the bridge driver. The DRM diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 3fa0275e509f..bb214a114329 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -1118,12 +1118,33 @@ struct drm_plane { /** * struct drm_bridge_funcs - drm_bridge control functions - * @attach: Called during drm_bridge_attach */ struct drm_bridge_funcs { + /** + * @attach: + * + * This callback is invoked whenever our bridge is being attached to a + * &drm_encoder. + * + * The attach callback is optional. + * + * RETURNS: + * + * Zero on success, error code on failure. + */ int (*attach)(struct drm_bridge *bridge); /** + * @detach: + * + * This callback is invoked whenever our bridge is being detached from a + * &drm_encoder. + * + * The detach callback is optional. + */ + void (*detach)(struct drm_bridge *bridge); + + /** * @mode_fixup: * * This callback is used to validate and adjust a mode. The paramater @@ -1137,6 +1158,8 @@ struct drm_bridge_funcs { * this function passes all other callbacks must succeed for this * configuration. * + * The mode_fixup callback is optional. + * * NOTE: * * This function is called in the check phase of atomic modesets, which @@ -2426,6 +2449,7 @@ extern int drm_bridge_add(struct drm_bridge *bridge); extern void drm_bridge_remove(struct drm_bridge *bridge); extern struct drm_bridge *of_drm_find_bridge(struct device_node *np); extern int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge); +extern void drm_bridge_detach(struct drm_bridge *bridge); bool drm_bridge_mode_fixup(struct drm_bridge *bridge, const struct drm_display_mode *mode, |