Hi Daniel,
Thanks for the quick review.
On Tuesday, 26 November 2019 14:26:10 GMT Daniel Vetter wrote:
On Tue, Nov 26, 2019 at 01:15:59PM +0000, Mihail Atanassov wrote:
A simple convenience function to initialize the struct drm_bridge.
Signed-off-by: Mihail Atanassov mihail.atanassov@arm.com
The commit message here leaves figuring out why we need this to the reader. Reading ahead the reasons seems to be to roll out bridge->dev setting for everyone, so that we can set the device_link. Please explain that in the commit message so the patch is properly motivated.
Ack, but with one caveat: bridge->dev is the struct drm_device that is the bridge client, we need to add a bridge->device (patch 29 in this series) which is the struct device that will manage the bridge lifetime.
drivers/gpu/drm/drm_bridge.c | 29 +++++++++++++++++++++++++++++ include/drm/drm_bridge.h | 4 ++++ 2 files changed, 33 insertions(+)
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index cba537c99e43..cbe680aa6eac 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -89,6 +89,35 @@ void drm_bridge_remove(struct drm_bridge *bridge) } EXPORT_SYMBOL(drm_bridge_remove);
+/**
- drm_bridge_init - initialise a drm_bridge structure
- @bridge: bridge control structure
- @funcs: control functions
- @dev: device
- @timings: timing specification for the bridge; optional (may be NULL)
- @driver_private: pointer to the bridge driver internal context (may be NULL)
Please also sprinkle some links to this new function to relevant places, I'd add at least:
"Drivers should call drm_bridge_init() first." to the kerneldoc for drm_bridge_add. drm_bridge_add should also mention drm_bridge_remove as the undo function.
And perhaps a longer paragraph to &struct drm_bridge:
"Bridge drivers should call drm_bridge_init() to initialized a bridge driver, and then register it with drm_bridge_add().
"Users of bridges link a bridge driver into their overall display output pipeline by calling drm_bridge_attach()."
Will do.
- */
+void drm_bridge_init(struct drm_bridge *bridge, struct device *dev,
const struct drm_bridge_funcs *funcs,const struct drm_bridge_timings *timings,void *driver_private)+{
- WARN_ON(!funcs);
- bridge->dev = NULL;
Given that the goal here is to get bridge->dev set up, why not
WARN_ON(!dev); bridge->dev = dev;
See above struct device vs struct drm_device. I add a
bridge->device = dev;
in patch 29, which takes care of that. I skipped the warn since there's a dereference of dev, but I now realized it's behind CONFIG_OF, so I'll add it in for v2.
Yes, 'device' isn't the best of names, but I took Russell's patch almost as-is, I didn't have any better ideas for bikeshedding.
That should help us to really move forward with all this. -Daniel
- bridge->encoder = NULL;
- bridge->next = NULL;
+#ifdef CONFIG_OF
- bridge->of_node = dev->of_node;
+#endif
- bridge->timings = timings;
- bridge->funcs = funcs;
- bridge->driver_private = driver_private;
+} +EXPORT_SYMBOL(drm_bridge_init);
/**
- drm_bridge_attach - attach the bridge to an encoder's chain
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index c0a2286a81e9..d6d9d5301551 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -402,6 +402,10 @@ struct drm_bridge {
void drm_bridge_add(struct drm_bridge *bridge); void drm_bridge_remove(struct drm_bridge *bridge); +void drm_bridge_init(struct drm_bridge *bridge, struct device *dev,
const struct drm_bridge_funcs *funcs,const struct drm_bridge_timings *timings,void *driver_private);struct drm_bridge *of_drm_find_bridge(struct device_node *np); int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge, struct drm_bridge *previous);