Hi David,
On Wed, 2016-03-23 at 12:13 +0100, David Herrmann wrote:
Hi
On Wed, Mar 23, 2016 at 9:42 AM, Alexey Brodkin Alexey.Brodkin@synopsys.com wrote:
As a pair to already existing drm_connector_unregister_all() we're adding generic implementation of what is already done in some drivers.
Once this helper is implemented we'll be ready to switch existing driver-specific implementations with the generic one.
Signed-off-by: Alexey Brodkin abrodkin@synopsys.com Cc: Daniel Vetter daniel@ffwll.ch Cc: David Airlie airlied@linux.ie
Changes v2 -> v3: * Updated title with capital after colon * Simplified failure path with direct and unconditional invocation of unregister_all() * Updated kerneldoc description of the drm_connector_register_all()
Changes v1 -> v2: * Rename drm_connector_unplug_all() to drm_connector_unregister_all() * Use drm_for_each_connector() instead of list_for_each_entry() * Updated kerneldoc for drm_dev_register()
drivers/gpu/drm/drm_crtc.c | 43 +++++++++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/drm_drv.c | 6 +++++- include/drm/drm_crtc.h | 3 ++- 3 files changed, 50 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 65488a6..21eea11 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1081,6 +1081,49 @@ void drm_connector_unregister(struct drm_connector *connector) EXPORT_SYMBOL(drm_connector_unregister);
/**
- drm_connector_register_all - register all connectors
- @dev: drm device
- This function registers all connectors in sysfs and other places so that
- userspace can start to access them. Drivers can call it after calling
- drm_dev_register() to complete the device registration, if they don't call
- drm_connector_register() on each connector individually.
- When a device is unplugged and should be removed from userspace access,
- call drm_connector_unregister_all(), which is the inverse of this
- function.
- Returns:
- Zero on success, error code on failure.
- */
+int drm_connector_register_all(struct drm_device *dev) +{ + struct drm_connector *connector; + int ret;
+ mutex_lock(&dev->mode_config.mutex);
+ drm_for_each_connector(connector, dev) { + ret = drm_connector_register(connector); + if (ret) { + /* + * We may safely call unregister_all() here within + * area locked with mutex because unregister_all() + * doesn't use locks inside (see a comment in that + * function). + */
Ugh? unregister_all() says:
/* FIXME: taking the mode config mutex ends up in a clash with sysfs */
This strongly contradicts your comment. Anyway, regardless how you want to fix it: You better unlock the mode-config mutex before returning below.
So good catch. But what I really meant since we didn't get any further after registering all "good" connections (see we're not releasing mutex still) the will be no clashes with sysfs.
Still I;d like Daniel to comment on that separately.
-Alexey