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Diffstat (limited to 'kernel/include/media/v4l2-device.h')
| -rw-r--r-- | kernel/include/media/v4l2-device.h | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/kernel/include/media/v4l2-device.h b/kernel/include/media/v4l2-device.h new file mode 100644 index 000000000..9c5815787 --- /dev/null +++ b/kernel/include/media/v4l2-device.h @@ -0,0 +1,212 @@ +/* + V4L2 device support header. + + Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef _V4L2_DEVICE_H +#define _V4L2_DEVICE_H + +#include <media/media-device.h> +#include <media/v4l2-subdev.h> +#include <media/v4l2-dev.h> + +/* Each instance of a V4L2 device should create the v4l2_device struct, + either stand-alone or embedded in a larger struct. + + It allows easy access to sub-devices (see v4l2-subdev.h) and provides + basic V4L2 device-level support. + */ + +#define V4L2_DEVICE_NAME_SIZE (20 + 16) + +struct v4l2_ctrl_handler; + +struct v4l2_device { + /* 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; +#if defined(CONFIG_MEDIA_CONTROLLER) + struct media_device *mdev; +#endif + /* used to keep track of the registered subdevs */ + struct list_head subdevs; + /* lock this struct; can be used by the driver as well if this + struct is embedded into a larger struct. */ + 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); + /* The control handler. May be NULL. */ + struct v4l2_ctrl_handler *ctrl_handler; + /* Device's priority state */ + struct v4l2_prio_state prio; + /* Keep track of the references to this struct. */ + struct kref ref; + /* Release function that is called when the ref count goes to 0. */ + void (*release)(struct v4l2_device *v4l2_dev); +}; + +static inline void v4l2_device_get(struct v4l2_device *v4l2_dev) +{ + kref_get(&v4l2_dev->ref); +} + +int v4l2_device_put(struct v4l2_device *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); + +/* Optional function to initialize the name field of struct v4l2_device using + the driver name and a driver-global atomic_t instance. + This function will increment the instance counter and returns the instance + value used in the name. + + Example: + + static atomic_t drv_instance = ATOMIC_INIT(0); + + ... + + instance = v4l2_device_set_name(&v4l2_dev, "foo", &drv_instance); + + The first time this is called the name field will be set to foo0 and + this function returns 0. If the name ends with a digit (e.g. cx18), + then the name will be set to cx18-0 since cx180 looks really odd. */ +int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename, + atomic_t *instance); + +/* 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 *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); + +/* Register device nodes for all subdev of the v4l2 device that are marked with + * the V4L2_SUBDEV_FL_HAS_DEVNODE flag. + */ +int __must_check +v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev); + +/* Send a notification to v4l2_device. */ +static inline void v4l2_subdev_notify(struct v4l2_subdev *sd, + unsigned int notification, void *arg) +{ + if (sd && sd->v4l2_dev && sd->v4l2_dev->notify) + sd->v4l2_dev->notify(sd, notification, arg); +} + +/* Iterate over all subdevs. */ +#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_p(v4l2_dev, sd, cond, o, f, args...) \ + do { \ + 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) + +#define __v4l2_device_call_subdevs(v4l2_dev, cond, o, f, args...) \ + do { \ + struct v4l2_subdev *__sd; \ + \ + __v4l2_device_call_subdevs_p(v4l2_dev, __sd, cond, o, \ + f , ##args); \ + } while (0) + +/* Call the specified callback for all subdevs matching the condition. + 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_p(v4l2_dev, sd, cond, o, f, args...) \ +({ \ + long __err = 0; \ + \ + 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) \ + break; \ + } \ + (__err == -ENOIOCTLCMD) ? 0 : __err; \ +}) + +#define __v4l2_device_call_subdevs_until_err(v4l2_dev, cond, o, f, args...) \ +({ \ + struct v4l2_subdev *__sd; \ + __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, cond, o, \ + f , ##args); \ +}) + +/* 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(v4l2_dev, grpid, o, f, args...) \ + do { \ + struct v4l2_subdev *__sd; \ + \ + __v4l2_device_call_subdevs_p(v4l2_dev, __sd, \ + !(grpid) || __sd->grp_id == (grpid), o, f , \ + ##args); \ + } while (0) + +/* 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(v4l2_dev, grpid, o, f, args...) \ +({ \ + struct v4l2_subdev *__sd; \ + __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, \ + !(grpid) || __sd->grp_id == (grpid), o, f , \ + ##args); \ +}) + +#define v4l2_device_has_op(v4l2_dev, o, f) \ +({ \ + struct v4l2_subdev *__sd; \ + bool __result = false; \ + list_for_each_entry(__sd, &(v4l2_dev)->subdevs, list) { \ + if (v4l2_subdev_has_op(__sd, o, f)) { \ + __result = true; \ + break; \ + } \ + } \ + __result; \ +}) + +#endif |