Re: [PATCH 1/3] drm: introduce drm_connector_plug_all() helper

On Fri, Mar 18, 2016 at 01:01:42PM +0300, Alexey Brodkin wrote:

As a pair to already existing drm_connector_unplug_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 generic one.

Signed-off-by: Alexey Brodkin abrodkin@synopsys.com Cc: Daniel Vetter daniel@ffwll.ch Cc: David Airlie airlied@linux.ie

---

drivers/gpu/drm/drm_crtc.c | 44 +++++++++++++++++++++++++++++++++++++++++++- drivers/gpu/drm/drm_drv.c | 3 ++- include/drm/drm_crtc.h | 3 ++- 3 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 65258ac..ce27420 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1080,6 +1080,46 @@ void drm_connector_unregister(struct drm_connector *connector) } EXPORT_SYMBOL(drm_connector_unregister);

+/**

• • drm_connector_plug_all - register connector userspace interfaces
• • @dev: drm device
• • This function registers all connector userspace interfaces in sysfs. Should
• • be call when the device is disconnected, e.g. from an usb driver's

Still talks about disconnect ;-) Please also mention that this just calls drm_connector_register() exactly like this including () to generate a kerneldoc hyperlink.

• • ->connect callback.

Returns: section is missing, specifying how this can fail. Just copy the one from connector_register().

• */

+int drm_connector_plug_all(struct drm_device *dev) +{

• struct drm_connector *connector, *failed;
• int ret;
• mutex_lock(&dev->mode_config.mutex);
• list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

for_each_connector here please. And the s/plug/register/ naming discussion we've had.

• ret = drm_connector_register(connector);
  

• if (ret) {
  

• 	failed = connector;
  

• 	goto err;
  

• }
  

• }
• mutex_unlock(&dev->mode_config.mutex);
• return 0;

+err:

• list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

• if (failed == connector)
  

• 	break;
  

• drm_connector_unregister(connector);
  

• }
• mutex_unlock(&dev->mode_config.mutex);
• return ret;

+} +EXPORT_SYMBOL(drm_connector_plug_all);

/**

• drm_connector_unplug_all - unregister connector userspace interfaces

@@ -1093,10 +1133,12 @@ void drm_connector_unplug_all(struct drm_device *dev) { struct drm_connector *connector;

• /* FIXME: taking the mode config mutex ends up in a clash with sysfs */

• mutex_lock(&dev->mode_config.mutex);

You can't drop that FIXME, the bug is still there.

• list_for_each_entry(connector, &dev->mode_config.connector_list, head) drm_connector_unregister(connector);

• mutex_unlock(&dev->mode_config.mutex);

} EXPORT_SYMBOL(drm_connector_unplug_all);

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index 167c8d3..4a559c6 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -715,7 +715,8 @@ EXPORT_SYMBOL(drm_dev_unref);

• Register the DRM device @dev with the system, advertise device to user-space
• and start normal device operation. @dev must be allocated via drm_dev_alloc()

• • previously.

• • previously and right after drm_dev_register() driver should call

It'd do 2 sentences here for simplicity, not connect them with and. Also "... _the_ driver should ..."

• • drm_connector_plug_all() to register all connectors in sysfs.

Maybe mention why this is separate: "This is a separate call for backwards compatibility with drivers still using the deprecated ->load() callback, where connectors are registered from within the ->load() callback."

Besides these details looks good. -Daniel

• Never call this twice on any device!

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 8c7fb3d..aa8789e 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -2214,7 +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 */ +/* helpers to plug/unplug all connectors to/from sysfs for device */ +extern int drm_connector_plug_all(struct drm_device *dev); extern void drm_connector_unplug_all(struct drm_device *dev);

extern int drm_bridge_add(struct drm_bridge *bridge);

2.5.0