diff options
Diffstat (limited to 'include/media/v4l2-device.h')
| -rw-r--r-- | include/media/v4l2-device.h | 40 |
1 files changed, 26 insertions, 14 deletions
diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h index 55e41af..0dd3e8e 100644 --- a/include/media/v4l2-device.h +++ b/include/media/v4l2-device.h @@ -33,7 +33,9 @@ #define V4L2_DEVICE_NAME_SIZE (BUS_ID_SIZE + 16) struct v4l2_device { - /* dev->driver_data points to this struct */ + /* dev->driver_data points to this struct. + Note: dev might be NULL if there is no parent device + as is the case with e.g. ISA devices. */ struct device *dev; /* used to keep track of the registered subdevs */ struct list_head subdevs; @@ -42,33 +44,43 @@ struct v4l2_device { spinlock_t lock; /* unique device name, by default the driver name + bus ID */ char name[V4L2_DEVICE_NAME_SIZE]; + /* notify callback called by some sub-devices. */ + void (*notify)(struct v4l2_subdev *sd, + unsigned int notification, void *arg); }; -/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev */ +/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev. + dev may be NULL in rare cases (ISA devices). In that case you + must fill in the v4l2_dev->name field before calling this function. */ int __must_check v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev); -/* Set v4l2_dev->dev->driver_data to NULL and unregister all sub-devices */ +/* Set v4l2_dev->dev to NULL. Call when the USB parent disconnects. + Since the parent disappears this ensures that v4l2_dev doesn't have an + invalid parent pointer. */ +void v4l2_device_disconnect(struct v4l2_device *v4l2_dev); +/* Unregister all sub-devices and any other resources related to v4l2_dev. */ void v4l2_device_unregister(struct v4l2_device *v4l2_dev); /* Register a subdev with a v4l2 device. While registered the subdev module is marked as in-use. An error is returned if the module is no longer loaded when you attempt to register it. */ -int __must_check v4l2_device_register_subdev(struct v4l2_device *dev, struct v4l2_subdev *sd); +int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, + struct v4l2_subdev *sd); /* Unregister a subdev with a v4l2 device. Can also be called if the subdev wasn't registered. In that case it will do nothing. */ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd); /* Iterate over all subdevs. */ -#define v4l2_device_for_each_subdev(sd, dev) \ - list_for_each_entry(sd, &(dev)->subdevs, list) +#define v4l2_device_for_each_subdev(sd, v4l2_dev) \ + list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) /* Call the specified callback for all subdevs matching the condition. Ignore any errors. Note that you cannot add or delete a subdev while walking the subdevs list. */ -#define __v4l2_device_call_subdevs(dev, cond, o, f, args...) \ +#define __v4l2_device_call_subdevs(v4l2_dev, cond, o, f, args...) \ do { \ struct v4l2_subdev *sd; \ \ - list_for_each_entry(sd, &(dev)->subdevs, list) \ + list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) \ if ((cond) && sd->ops->o && sd->ops->o->f) \ sd->ops->o->f(sd , ##args); \ } while (0) @@ -77,12 +89,12 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd); If the callback returns an error other than 0 or -ENOIOCTLCMD, then return with that error code. Note that you cannot add or delete a subdev while walking the subdevs list. */ -#define __v4l2_device_call_subdevs_until_err(dev, cond, o, f, args...) \ +#define __v4l2_device_call_subdevs_until_err(v4l2_dev, cond, o, f, args...) \ ({ \ struct v4l2_subdev *sd; \ long err = 0; \ \ - list_for_each_entry(sd, &(dev)->subdevs, list) { \ + list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) { \ if ((cond) && sd->ops->o && sd->ops->o->f) \ err = sd->ops->o->f(sd , ##args); \ if (err && err != -ENOIOCTLCMD) \ @@ -94,16 +106,16 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd); /* Call the specified callback for all subdevs matching grp_id (if 0, then match them all). Ignore any errors. Note that you cannot add or delete a subdev while walking the subdevs list. */ -#define v4l2_device_call_all(dev, grpid, o, f, args...) \ - __v4l2_device_call_subdevs(dev, \ +#define v4l2_device_call_all(v4l2_dev, grpid, o, f, args...) \ + __v4l2_device_call_subdevs(v4l2_dev, \ !(grpid) || sd->grp_id == (grpid), o, f , ##args) /* Call the specified callback for all subdevs matching grp_id (if 0, then match them all). If the callback returns an error other than 0 or -ENOIOCTLCMD, then return with that error code. Note that you cannot add or delete a subdev while walking the subdevs list. */ -#define v4l2_device_call_until_err(dev, grpid, o, f, args...) \ - __v4l2_device_call_subdevs_until_err(dev, \ +#define v4l2_device_call_until_err(v4l2_dev, grpid, o, f, args...) \ + __v4l2_device_call_subdevs_until_err(v4l2_dev, \ !(grpid) || sd->grp_id == (grpid), o, f , ##args) #endif |