Re: [PATCH 2/4 v2] drm: introduce drm_connector_register_all() helper

Hi Alexey,

Thank you for the patch.

On Monday 21 Mar 2016 15:28:38 Alexey Brodkin 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 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 | 50 ++++++++++++++++++++++++++++++++++++++++--- drivers/gpu/drm/drm_drv.c | 6 +++++- include/drm/drm_crtc.h | 3 ++- 3 files changed, 54 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 76453cd..2ad0ce9 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1080,13 +1080,57 @@ 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 just calls drm_connector_register() for all connectors.
• • Should be called when the device is disconnected, e.g. from an usb

driver's

• • ->connect callback.

There's no such thing as a USB driver connect callback :-)

• • Returns:
• • Zero on success, error code on failure.
• */

+int drm_connector_register_all(struct drm_device *dev) +{

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

• ret = drm_connector_register(connector);
  

• if (ret) {
  

• 	failed = connector;
  

• 	goto err;
  

• }
  

• }

One blank line is enough.

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

+err:

• drm_for_each_connector(connector, dev) {

• if (failed == connector)
  

• 	break;
  

• drm_connector_unregister(connector);
  

• }

drm_connector_unregister() can safely be called on unregistered connectors, so you could simplify the implementation by calling drm_connector_unregister_all() above and remove the goto and this piece of error handling code.

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

+} +EXPORT_SYMBOL(drm_connector_register_all);

/**

• drm_connector_unregister_all - unregister connector userspace interfaces
• @dev: drm device
  • This function unregisters all connector userspace interfaces in sysfs.

Should

• • be call when the device is disconnected, e.g. from an usb driver's

• • be called when the device is disconnected, e.g. from an usb driver's
  • ->disconnect callback.
  */

void drm_connector_unregister_all(struct drm_device *dev) @@ -1094,9 +1138,9 @@ void drm_connector_unregister_all(struct drm_device *dev) struct drm_connector *connector;

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

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

• drm_for_each_connector(connector, dev) { drm_connector_unregister(connector);

• }

} EXPORT_SYMBOL(drm_connector_unregister_all);

I would move these two hunks to the previous patch as you already touch drm_connector_unregister_all() there, but that's up to you.

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index 167c8d3..5580a90 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -715,7 +715,11 @@ 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. Right after drm_dev_register() the driver should call
• • drm_connector_plug_all() to register all connectors in sysfs. This is

s/drm_connector_plug_all/drm_connector_register_all/

• • a separate call for backward compatibility with drivers still using
• • the deprecated ->load() callback, where connectors are registered from

within

• • the ->load() callback.
  • Never call this twice on any device!

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 42d9f4d..6a34117 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 unregister all connectors from sysfs for device */ +/* helpers to {un}register all connectors from sysfs for device */ +extern int drm_connector_register_all(struct drm_device *dev); extern void drm_connector_unregister_all(struct drm_device *dev);

extern int drm_bridge_add(struct drm_bridge *bridge);