kernel/linux.git/include/drm/drm_managed.h, branch v6.19.11

drm: Simplify drmm_alloc_ordered_workqueue return

2025-07-03T17:14:56+00:00

Rather than returning ERR_PTR or NULL on failure, replace the NULL return with ERR_PTR(-ENOMEM). This simplifies error handling at the caller. While here, add kernel documentation for drmm_alloc_ordered_workqueue. Cc: Louis Chauvet Signed-off-by: Matthew Brost Reviewed-by: Louis Chauvet Link: https://lore.kernel.org/r/20250702232831.3271328-2-matthew.brost@intel.com

drm/managed: Add DRM-managed alloc_ordered_workqueue

2025-01-21T09:32:31+00:00

Add drmm_alloc_ordered_workqueue(), a helper that provides managed ordered workqueue cleanup. The workqueue will be destroyed with the final reference of the DRM device. Reviewed-by: Thomas Zimmermann Reviewed-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20250116-google-vkms-managed-v9-3-3e4ae1bd05a0@bootlin.com Signed-off-by: Louis Chauvet

drm/managed: Add drmm_release_action

2024-01-17T09:38:39+00:00

Similar to devres equivalent, it allows to call the "release" action directly and remove the resource from the managed resources list. Signed-off-by: Michał Winiarski Reviewed-by: Maxime Ripard Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20240115171351.504264-2-michal.winiarski@intel.com

drm: fix drmm_mutex_init()

2023-05-22T10:23:50+00:00

In mutex_init() lockdep identifies a lock by defining a special static key for each lock class. However if we wrap the macro in a function, like in drmm_mutex_init(), we end up generating: int drmm_mutex_init(struct drm_device *dev, struct mutex *lock) { static struct lock_class_key __key; __mutex_init((lock), "lock", &__key); .... } The static __key here is what lockdep uses to identify the lock class, however since this is just a normal function the key here will be created once, where all callers then use the same key. In effect the mutex->depmap.key will be the same pointer for different drmm_mutex_init() callers. This then results in impossible lockdep splats since lockdep thinks completely unrelated locks are the same lock class. To fix this turn drmm_mutex_init() into a macro such that it generates a different "static struct lock_class_key __key" for each invocation, which looks to be inline with what mutex_init() wants. v2: - Revamp the commit message with clearer explanation of the issue. - Rather export __drmm_mutex_release() than static inline. Reported-by: Thomas Hellström Reported-by: Sarah Walker Fixes: e13f13e039dc ("drm: Add DRM-managed mutex_init()") Cc: Stanislaw Gruszka Cc: Boris Brezillon Cc: Thomas Zimmermann Cc: Jocelyn Falempe Cc: Daniel Vetter Cc: dri-devel@lists.freedesktop.org Signed-off-by: Matthew Auld Reviewed-by: Boris Brezillon Reviewed-by: Stanislaw Gruszka Reviewed-by: Lucas De Marchi Acked-by: Thomas Zimmermann Signed-off-by: Thomas Zimmermann Link: https://patchwork.freedesktop.org/patch/msgid/20230519090733.489019-1-matthew.auld@intel.com

drm: Add DRM-managed mutex_init()

2022-05-05T07:04:10+00:00

Add drmm_mutex_init(), a helper that provides managed mutex cleanup. The mutex will be destroyed with the final reference of the DRM device. Signed-off-by: Thomas Zimmermann Reviewed-by: Jocelyn Falempe Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20220502142514.2174-2-tzimmermann@suse.de

drm: Remove drmm_add_final_kfree() declaration from public headers

2020-12-05T19:01:12+00:00

The drmm_add_final_kfree() function is declared in the include/drm/drm_managed.h public header, but has become an internal API not exposed to drivers. Drop it from drm_managed.h as it's already declared in drm_internal.h. Signed-off-by: Laurent Pinchart Acked-by: Thomas Zimmermann Signed-off-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20201204092932.21636-1-laurent.pinchart+renesas@ideasonboard.com

drm: Add docs for managed resources

2020-03-26T15:09:48+00:00

All collected together to provide a consistent story in one patch, instead of the somewhat bumpy refactor-evolution leading to this. Also some thoughts on what the next steps could be: - Create a macro called devm_drm_dev_alloc() which essentially wraps the kzalloc(); devm_drm_dev_init(); drmm_add_final_kfree() combo. Needs to be a macro since we'll have to do some typeof trickery and casting to make this fully generic for all drivers that embed struct drm_device into their own thing. - A lot of the simple drivers now have essentially just drm_dev_unplug(); drm_atomic_helper_shutdown(); as their $bus_driver->remove hook. We could create a devm_mode_config_reset which sets drm_atomic_helper_shutdown as it's cleanup action, and a devm_drm_dev_register with drm_dev_unplug as it's cleanup action, and simple drivers wouldn't have a need for a ->remove function at all, and we could delete them. - For more complicated drivers we need drmm_ versions of a _lot_ more things. All the userspace visible objects (crtc, plane, encoder, crtc), anything else hanging of those (maybe a drmm_get_edid, at least for panels and other built-in stuff). Also some more thoughts on why we're not reusing devm_ with maybe a fake struct device embedded into the drm_device (we can't use the kdev, since that's in each drm_minor). - Code review gets extremely tricky, since every time you see a devm_ you need to carefully check whether the fake device (with the drm_device lifetim) or the real device (with the lifetim of the underlying physical device and driver binding) are used. That's not going to help at all, and we have enormous amounts of drivers who use devm_ where they really shouldn't. Having different types makes sure the compiler type checks this for us and ensures correctness. - The set of functions are very much non-overlapping. E.g. devm_ioremap makes total sense, drmm_ioremap has the wrong lifetime, since hw resources need to be cleaned out at driver unbind and wont outlive that like a drm_device. Similar, but other way round for drmm_connector_init (which is the only correct version, devm_ for drm_connector is just buggy). Simply not having the wrong version again prevents bugs. Finally I guess this opens a huge todo for all the drivers. I'm semi-tempted to do a tree-wide s/devm_kzalloc/drmm_kzalloc/ since most likely that'll fix an enormous amount of bugs and most likely not cause any issues at all (aside from maybe holding onto memory slightly too long). v2: - Doc improvements from Laurent. - Also add kerneldoc for the new drmm_add_action_or_reset. v3: - Remove kerneldoc for drmm_remove_action. Reviewed-by: Sam Ravnborg Cc: Sam Ravnborg Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Cc: Laurent Pinchart Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Signed-off-by: Daniel Vetter fixup docs Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-52-daniel.vetter@ffwll.ch

drm: Manage drm_vblank_cleanup with drmm_

2020-03-26T14:38:17+00:00

Nothing special here, except that this is the first time that we automatically clean up something that's initialized with an explicit driver call. But the cleanup was done at the very end of the release sequence for all drivers, and that's still the case. At least without more uses of drmm_ through explicit driver calls. Also for this one we need drmm_kcalloc, so lets add those. The motivation here is to allow us to remove the explicit calls to drm_dev_fini() from all drivers. v2: Sort includes (Laurent) v3: Motivate the change in the commit message better (Sam) Acked-by: Sam Ravnborg Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-25-daniel.vetter@ffwll.ch

drm: manage drm_minor cleanup with drmm_

2020-03-26T14:37:31+00:00

The cleanup here is somewhat tricky, since we can't tell apart the allocated minor index from 0. So register a cleanup action first, and if the index allocation fails, unregister that cleanup action again to avoid bad mistakes. The kdev for the minor already handles NULL, so no problem there. Hence add drmm_remove_action() to the drm_managed library. v2: Make pointer math around void ** consistent with what Laurent suggested. v3: Use drmm_add_action_or_reset and remove drmm_remove_action. Noticed because of some questions from Thomas. This also means we need to move the drmm_add_action_or_reset helper earlier in the series. v4: Uh ... fix slightly embarrassing bug CI spotted. Acked-by: Thomas Zimmermann Reviewed-by: Sam Ravnborg Cc: Thomas Zimmermann Cc: Laurent Pinchart Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20200324203936.3330994-1-daniel.vetter@ffwll.ch

drm: Handle dev->unique with drmm_

2020-03-26T14:36:20+00:00

We need to add a drmm_kstrdup for this, but let's start somewhere. This is not exactly perfect onion unwinding, but it's jsut a kfree so doesn't really matter at all. Reviewed-by: Sam Ravnborg Acked-by: Thomas Zimmermann Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-21-daniel.vetter@ffwll.ch