/* 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/v4l2-subdev.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 (BUS_ID_SIZE + 16) 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; /* 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); }; /* 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 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); /* 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(v4l2_dev, cond, o, f, args...) \ do { \ struct v4l2_subdev *sd; \ \ 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) /* 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(v4l2_dev, cond, o, f, args...) \ ({ \ struct v4l2_subdev *sd; \ 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; \ }) /* 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...) \ __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(v4l2_dev, grpid, o, f, args...) \ __v4l2_device_call_subdevs_until_err(v4l2_dev, \ !(grpid) || sd->grp_id == (grpid), o, f , ##args) #endif