| Message ID | 1433111079-22457-1-git-send-email-sakari.ailus@iki.fi (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Sakari, Thank you for the patch. Please see below for one small comment. On Monday 01 June 2015 01:24:39 Sakari Ailus wrote: > V4L2 async sub-devices are currently matched (OF case) based on the struct > device_node pointer in struct device. LED devices may have more than one > LED, and in that case the OF node to match is not directly the device's > node, but a LED's node. > > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> > --- > since v1: > > - Move conditional setting of struct v4l2_subdev.of_node from > v4l2_device_register_subdev() to v4l2_async_register_subdev. > > - Remove the check for NULL struct v4l2_subdev.of_node from match_of() as > it's no longer needed. > > - Unconditionally state in the struct v4l2_subdev.of_node field comment that > the field contains (a pointer to) the sub-device's of_node. > > drivers/media/v4l2-core/v4l2-async.c | 34 +++++++++++++++++++++------------ > include/media/v4l2-subdev.h | 2 ++ > 2 files changed, 24 insertions(+), 12 deletions(-) > > diff --git a/drivers/media/v4l2-core/v4l2-async.c > b/drivers/media/v4l2-core/v4l2-async.c index 85a6a34..b0badac 100644 > --- a/drivers/media/v4l2-core/v4l2-async.c > +++ b/drivers/media/v4l2-core/v4l2-async.c [snip] > @@ -266,6 +273,9 @@ int v4l2_async_register_subdev(struct v4l2_subdev *sd) > { > struct v4l2_async_notifier *notifier; > > + if (!sd->of_node && sd->dev) > + sd->of_node = sd->dev->of_node; > + I think we don't need to take a reference to of_node here, as we assume there's a reference to dev through the whole life of the subdev, and dev should have a reference to of_node, but could you double-check ? If that's indeed not a problem, Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> (and maybe a small comment in the source code would be useful) > mutex_lock(&list_lock); > > INIT_LIST_HEAD(&sd->async_list); > diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h > index 8f5da73..8a17c24 100644 > --- a/include/media/v4l2-subdev.h > +++ b/include/media/v4l2-subdev.h > @@ -603,6 +603,8 @@ struct v4l2_subdev { > struct video_device *devnode; > /* pointer to the physical device, if any */ > struct device *dev; > + /* A device_node of the subdev, usually the same as dev->of_node. */ > + struct device_node *of_node; > /* Links this subdev to a global subdev_list or @notifier->done list. */ > struct list_head async_list; > /* Pointer to respective struct v4l2_async_subdev. */
Hi Laurent, On Tue, Jun 02, 2015 at 05:47:12AM +0300, Laurent Pinchart wrote: > Hi Sakari, > > Thank you for the patch. Please see below for one small comment. > > On Monday 01 June 2015 01:24:39 Sakari Ailus wrote: > > V4L2 async sub-devices are currently matched (OF case) based on the struct > > device_node pointer in struct device. LED devices may have more than one > > LED, and in that case the OF node to match is not directly the device's > > node, but a LED's node. > > > > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > > Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> > > --- > > since v1: > > > > - Move conditional setting of struct v4l2_subdev.of_node from > > v4l2_device_register_subdev() to v4l2_async_register_subdev. > > > > - Remove the check for NULL struct v4l2_subdev.of_node from match_of() as > > it's no longer needed. > > > > - Unconditionally state in the struct v4l2_subdev.of_node field comment that > > the field contains (a pointer to) the sub-device's of_node. > > > > drivers/media/v4l2-core/v4l2-async.c | 34 +++++++++++++++++++++------------ > > include/media/v4l2-subdev.h | 2 ++ > > 2 files changed, 24 insertions(+), 12 deletions(-) > > > > diff --git a/drivers/media/v4l2-core/v4l2-async.c > > b/drivers/media/v4l2-core/v4l2-async.c index 85a6a34..b0badac 100644 > > --- a/drivers/media/v4l2-core/v4l2-async.c > > +++ b/drivers/media/v4l2-core/v4l2-async.c > > [snip] > > > @@ -266,6 +273,9 @@ int v4l2_async_register_subdev(struct v4l2_subdev *sd) > > { > > struct v4l2_async_notifier *notifier; > > > > + if (!sd->of_node && sd->dev) > > + sd->of_node = sd->dev->of_node; > > + > > I think we don't need to take a reference to of_node here, as we assume > there's a reference to dev through the whole life of the subdev, and dev > should have a reference to of_node, but could you double-check ? > > If that's indeed not a problem, > > Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Good question. I don't think a reference would be needed also because we are only interested in the pointer value itself, the memory the pointer is pointing to is never accessed. As far as I can tell, there's no reference through the device. I can add a comment on this if you like. Perhaps it'd be a good idea actually, as you usually do take a reference in such cases.
diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c index 85a6a34..b0badac 100644 --- a/drivers/media/v4l2-core/v4l2-async.c +++ b/drivers/media/v4l2-core/v4l2-async.c @@ -22,10 +22,10 @@ #include <media/v4l2-device.h> #include <media/v4l2-subdev.h> -static bool match_i2c(struct device *dev, struct v4l2_async_subdev *asd) +static bool match_i2c(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) { #if IS_ENABLED(CONFIG_I2C) - struct i2c_client *client = i2c_verify_client(dev); + struct i2c_client *client = i2c_verify_client(sd->dev); return client && asd->match.i2c.adapter_id == client->adapter->nr && asd->match.i2c.address == client->addr; @@ -34,14 +34,24 @@ static bool match_i2c(struct device *dev, struct v4l2_async_subdev *asd) #endif } -static bool match_devname(struct device *dev, struct v4l2_async_subdev *asd) +static bool match_devname(struct v4l2_subdev *sd, + struct v4l2_async_subdev *asd) { - return !strcmp(asd->match.device_name.name, dev_name(dev)); + return !strcmp(asd->match.device_name.name, dev_name(sd->dev)); } -static bool match_of(struct device *dev, struct v4l2_async_subdev *asd) +static bool match_of(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) { - return dev->of_node == asd->match.of.node; + return sd->of_node == asd->match.of.node; +} + +static bool match_custom(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) +{ + if (!asd->match.custom.match) + /* Match always */ + return true; + + return asd->match.custom.match(sd->dev, asd); } static LIST_HEAD(subdev_list); @@ -51,17 +61,14 @@ static DEFINE_MUTEX(list_lock); static struct v4l2_async_subdev *v4l2_async_belongs(struct v4l2_async_notifier *notifier, struct v4l2_subdev *sd) { + bool (*match)(struct v4l2_subdev *, struct v4l2_async_subdev *); struct v4l2_async_subdev *asd; - bool (*match)(struct device *, struct v4l2_async_subdev *); list_for_each_entry(asd, ¬ifier->waiting, list) { /* bus_type has been verified valid before */ switch (asd->match_type) { case V4L2_ASYNC_MATCH_CUSTOM: - match = asd->match.custom.match; - if (!match) - /* Match always */ - return asd; + match = match_custom; break; case V4L2_ASYNC_MATCH_DEVNAME: match = match_devname; @@ -79,7 +86,7 @@ static struct v4l2_async_subdev *v4l2_async_belongs(struct v4l2_async_notifier * } /* match cannot be NULL here */ - if (match(sd->dev, asd)) + if (match(sd, asd)) return asd; } @@ -266,6 +273,9 @@ int v4l2_async_register_subdev(struct v4l2_subdev *sd) { struct v4l2_async_notifier *notifier; + if (!sd->of_node && sd->dev) + sd->of_node = sd->dev->of_node; + mutex_lock(&list_lock); INIT_LIST_HEAD(&sd->async_list); diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index 8f5da73..8a17c24 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -603,6 +603,8 @@ struct v4l2_subdev { struct video_device *devnode; /* pointer to the physical device, if any */ struct device *dev; + /* A device_node of the subdev, usually the same as dev->of_node. */ + struct device_node *of_node; /* Links this subdev to a global subdev_list or @notifier->done list. */ struct list_head async_list; /* Pointer to respective struct v4l2_async_subdev. */