diff options
author | David Herrmann <dh.herrmann@gmail.com> | 2014-07-23 11:38:38 +0200 |
---|---|---|
committer | David Herrmann <dh.herrmann@gmail.com> | 2014-08-05 16:08:21 +0200 |
commit | e17280758cc0b4f3d7065554006adcb87448f6c0 (patch) | |
tree | 71641f392c6ab39518ac56b2efa4763e7f5ecdd8 /drivers/gpu/drm/drm_sysfs.c | |
parent | drm: make minor->index available early (diff) | |
download | linux-e17280758cc0b4f3d7065554006adcb87448f6c0.tar.xz linux-e17280758cc0b4f3d7065554006adcb87448f6c0.zip |
drm: make sysfs device always available for minors
For each minor we allocate a sysfs device as minor->kdev. Currently, this
is allocated and registered in drm_minor_register(). This makes it
impossible to add sysfs-attributes to the device before it is registered.
Therefore, they are not added atomically, nor can we move device_add()
*after* ->load() is called.
This patch makes minor->kdev available early, but only adds the device
during minor-registration. Note that the registration is still called
before ->load() as debugfs needs to be split, too. This will be fixed in
follow-ups.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Diffstat (limited to 'drivers/gpu/drm/drm_sysfs.c')
-rw-r--r-- | drivers/gpu/drm/drm_sysfs.c | 90 |
1 files changed, 37 insertions, 53 deletions
diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c index 7827dad8fcf4..ab1a5f6dde8a 100644 --- a/drivers/gpu/drm/drm_sysfs.c +++ b/drivers/gpu/drm/drm_sysfs.c @@ -493,71 +493,55 @@ static void drm_sysfs_release(struct device *dev) } /** - * drm_sysfs_device_add - adds a class device to sysfs for a character driver - * @dev: DRM device to be added - * @head: DRM head in question + * drm_sysfs_minor_alloc() - Allocate sysfs device for given minor + * @minor: minor to allocate sysfs device for * - * Add a DRM device to the DRM's device model class. We use @dev's PCI device - * as the parent for the Linux device, and make sure it has a file containing - * the driver we're using (for userspace compatibility). + * This allocates a new sysfs device for @minor and returns it. The device is + * not registered nor linked. The caller has to use device_add() and + * device_del() to register and unregister it. + * + * Note that dev_get_drvdata() on the new device will return the minor. + * However, the device does not hold a ref-count to the minor nor to the + * underlying drm_device. This is unproblematic as long as you access the + * private data only in sysfs callbacks. device_del() disables those + * synchronously, so they cannot be called after you cleanup a minor. */ -int drm_sysfs_device_add(struct drm_minor *minor) +struct device *drm_sysfs_minor_alloc(struct drm_minor *minor) { - char *minor_str; + const char *minor_str; + struct device *kdev; int r; if (minor->type == DRM_MINOR_CONTROL) minor_str = "controlD%d"; - else if (minor->type == DRM_MINOR_RENDER) - minor_str = "renderD%d"; - else - minor_str = "card%d"; - - minor->kdev = kzalloc(sizeof(*minor->kdev), GFP_KERNEL); - if (!minor->kdev) { - r = -ENOMEM; - goto error; - } - - device_initialize(minor->kdev); - minor->kdev->devt = MKDEV(DRM_MAJOR, minor->index); - minor->kdev->class = drm_class; - minor->kdev->type = &drm_sysfs_device_minor; - minor->kdev->parent = minor->dev->dev; - minor->kdev->release = drm_sysfs_release; - dev_set_drvdata(minor->kdev, minor); - - r = dev_set_name(minor->kdev, minor_str, minor->index); + else if (minor->type == DRM_MINOR_RENDER) + minor_str = "renderD%d"; + else + minor_str = "card%d"; + + kdev = kzalloc(sizeof(*kdev), GFP_KERNEL); + if (!kdev) + return ERR_PTR(-ENOMEM); + + device_initialize(kdev); + kdev->devt = MKDEV(DRM_MAJOR, minor->index); + kdev->class = drm_class; + kdev->type = &drm_sysfs_device_minor; + kdev->parent = minor->dev->dev; + kdev->release = drm_sysfs_release; + dev_set_drvdata(kdev, minor); + + r = dev_set_name(kdev, minor_str, minor->index); if (r < 0) - goto error; - - r = device_add(minor->kdev); - if (r < 0) - goto error; - - return 0; + goto err_free; -error: - DRM_ERROR("device create failed %d\n", r); - put_device(minor->kdev); - return r; -} + return kdev; -/** - * drm_sysfs_device_remove - remove DRM device - * @dev: DRM device to remove - * - * This call unregisters and cleans up a class device that was created with a - * call to drm_sysfs_device_add() - */ -void drm_sysfs_device_remove(struct drm_minor *minor) -{ - if (minor->kdev) - device_unregister(minor->kdev); - minor->kdev = NULL; +err_free: + put_device(kdev); + return ERR_PTR(r); } - /** * drm_class_device_register - Register a struct device in the drm class. * |