diff options
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 16 | ||||
| -rw-r--r-- | drivers/media/video/Makefile | 2 | ||||
| -rw-r--r-- | drivers/media/video/v4l2-dev.c | 27 | ||||
| -rw-r--r-- | drivers/media/video/v4l2-device.c | 37 | ||||
| -rw-r--r-- | drivers/media/video/v4l2-subdev.c | 60 | ||||
| -rw-r--r-- | include/media/v4l2-dev.h | 18 | ||||
| -rw-r--r-- | include/media/v4l2-device.h | 6 | ||||
| -rw-r--r-- | include/media/v4l2-subdev.h | 14 |
8 files changed, 158 insertions, 22 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index f22f35c271f..8b358710b2f 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -319,6 +319,22 @@ controlled through GPIO pins. This distinction is only relevant when setting up the device, but once the subdev is registered it is completely transparent. +V4L2 sub-device userspace API +----------------------------- + +Beside exposing a kernel API through the v4l2_subdev_ops structure, V4L2 +sub-devices can also be controlled directly by userspace applications. + +Device nodes named v4l-subdevX can be created in /dev to access sub-devices +directly. If a sub-device supports direct userspace configuration it must set +the V4L2_SUBDEV_FL_HAS_DEVNODE flag before being registered. + +After registering sub-devices, the v4l2_device driver can create device nodes +for all registered sub-devices marked with V4L2_SUBDEV_FL_HAS_DEVNODE by calling +v4l2_device_register_subdev_nodes(). Those device nodes will be automatically +removed when sub-devices are unregistered. + + I2C sub-device drivers ---------------------- diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index ac54652396e..7ea65163090 100644 --- a/drivers/media/video/Makefile +++ b/drivers/media/video/Makefile @@ -11,7 +11,7 @@ stkwebcam-objs := stk-webcam.o stk-sensor.o omap2cam-objs := omap24xxcam.o omap24xxcam-dma.o videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o v4l2-fh.o \ - v4l2-event.o v4l2-ctrls.o + v4l2-event.o v4l2-ctrls.o v4l2-subdev.o # V4L2 core modules diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index 341764a3a99..abe04ef3806 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -408,13 +408,14 @@ static int get_index(struct video_device *vdev) } /** - * video_register_device - register video4linux devices + * __video_register_device - register video4linux devices * @vdev: video device structure we want to register * @type: type of device to register * @nr: which device node number (0 == /dev/video0, 1 == /dev/video1, ... * -1 == first free) * @warn_if_nr_in_use: warn if the desired device node number * was already in use and another number was chosen instead. + * @owner: module that owns the video device node * * The registration code assigns minor numbers and device node numbers * based on the requested type and registers the new device node with @@ -435,9 +436,11 @@ static int get_index(struct video_device *vdev) * %VFL_TYPE_VBI - Vertical blank data (undecoded) * * %VFL_TYPE_RADIO - A radio card + * + * %VFL_TYPE_SUBDEV - A subdevice */ -static int __video_register_device(struct video_device *vdev, int type, int nr, - int warn_if_nr_in_use) +int __video_register_device(struct video_device *vdev, int type, int nr, + int warn_if_nr_in_use, struct module *owner) { int i = 0; int ret; @@ -469,6 +472,9 @@ static int __video_register_device(struct video_device *vdev, int type, int nr, case VFL_TYPE_RADIO: name_base = "radio"; break; + case VFL_TYPE_SUBDEV: + name_base = "v4l-subdev"; + break; default: printk(KERN_ERR "%s called with unknown type: %d\n", __func__, type); @@ -552,7 +558,7 @@ static int __video_register_device(struct video_device *vdev, int type, int nr, goto cleanup; } vdev->cdev->ops = &v4l2_fops; - vdev->cdev->owner = vdev->fops->owner; + vdev->cdev->owner = owner; ret = cdev_add(vdev->cdev, MKDEV(VIDEO_MAJOR, vdev->minor), 1); if (ret < 0) { printk(KERN_ERR "%s: cdev_add failed\n", __func__); @@ -597,18 +603,7 @@ cleanup: vdev->minor = -1; return ret; } - -int video_register_device(struct video_device *vdev, int type, int nr) -{ - return __video_register_device(vdev, type, nr, 1); -} -EXPORT_SYMBOL(video_register_device); - -int video_register_device_no_warn(struct video_device *vdev, int type, int nr) -{ - return __video_register_device(vdev, type, nr, 0); -} -EXPORT_SYMBOL(video_register_device_no_warn); +EXPORT_SYMBOL(__video_register_device); /** * video_unregister_device - unregister a video4linux device diff --git a/drivers/media/video/v4l2-device.c b/drivers/media/video/v4l2-device.c index ce64fe16bc6..8c0ad8b372d 100644 --- a/drivers/media/video/v4l2-device.c +++ b/drivers/media/video/v4l2-device.c @@ -124,16 +124,20 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, /* Check for valid input */ if (v4l2_dev == NULL || sd == NULL || !sd->name[0]) return -EINVAL; + /* Warn if we apparently re-register a subdev */ WARN_ON(sd->v4l2_dev != NULL); + if (!try_module_get(sd->owner)) return -ENODEV; + sd->v4l2_dev = v4l2_dev; if (sd->internal_ops && sd->internal_ops->registered) { err = sd->internal_ops->registered(sd); if (err) return err; } + /* This just returns 0 if either of the two args is NULL */ err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler); if (err) { @@ -141,24 +145,57 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, sd->internal_ops->unregistered(sd); return err; } + spin_lock(&v4l2_dev->lock); list_add_tail(&sd->list, &v4l2_dev->subdevs); spin_unlock(&v4l2_dev->lock); + return 0; } EXPORT_SYMBOL_GPL(v4l2_device_register_subdev); +int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev) +{ + struct video_device *vdev; + struct v4l2_subdev *sd; + int err; + + /* Register a device node for every subdev marked with the + * V4L2_SUBDEV_FL_HAS_DEVNODE flag. + */ + list_for_each_entry(sd, &v4l2_dev->subdevs, list) { + if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE)) + continue; + + vdev = &sd->devnode; + strlcpy(vdev->name, sd->name, sizeof(vdev->name)); + vdev->v4l2_dev = v4l2_dev; + vdev->fops = &v4l2_subdev_fops; + vdev->release = video_device_release_empty; + err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1, + sd->owner); + if (err < 0) + return err; + } + + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes); + void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) { /* return if it isn't registered */ if (sd == NULL || sd->v4l2_dev == NULL) return; + spin_lock(&sd->v4l2_dev->lock); list_del(&sd->list); spin_unlock(&sd->v4l2_dev->lock); if (sd->internal_ops && sd->internal_ops->unregistered) sd->internal_ops->unregistered(sd); sd->v4l2_dev = NULL; + + video_unregister_device(&sd->devnode); module_put(sd->owner); } EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); diff --git a/drivers/media/video/v4l2-subdev.c b/drivers/media/video/v4l2-subdev.c new file mode 100644 index 00000000000..037aa28a5ed --- /dev/null +++ b/drivers/media/video/v4l2-subdev.c @@ -0,0 +1,60 @@ +/* + * V4L2 subdevice support. + * + * Copyright (C) 2010 Nokia Corporation + * + * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com> + * + * 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. + * + * 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 + */ + +#include <linux/types.h> +#include <linux/ioctl.h> +#include <linux/videodev2.h> + +#include <media/v4l2-device.h> +#include <media/v4l2-ioctl.h> + +static int subdev_open(struct file *file) +{ + return 0; +} + +static int subdev_close(struct file *file) +{ + return 0; +} + +static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) +{ + switch (cmd) { + default: + return -ENOIOCTLCMD; + } + + return 0; +} + +static long subdev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + return video_usercopy(file, cmd, arg, subdev_do_ioctl); +} + +const struct v4l2_file_operations v4l2_subdev_fops = { + .owner = THIS_MODULE, + .open = subdev_open, + .unlocked_ioctl = subdev_ioctl, + .release = subdev_close, +}; diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h index 15802a067a1..4fe6831b185 100644 --- a/include/media/v4l2-dev.h +++ b/include/media/v4l2-dev.h @@ -21,7 +21,8 @@ #define VFL_TYPE_GRABBER 0 #define VFL_TYPE_VBI 1 #define VFL_TYPE_RADIO 2 -#define VFL_TYPE_MAX 3 +#define VFL_TYPE_SUBDEV 3 +#define VFL_TYPE_MAX 4 struct v4l2_ioctl_callbacks; struct video_device; @@ -102,15 +103,26 @@ struct video_device /* dev to video-device */ #define to_video_device(cd) container_of(cd, struct video_device, dev) +int __must_check __video_register_device(struct video_device *vdev, int type, + int nr, int warn_if_nr_in_use, struct module *owner); + /* Register video devices. Note that if video_register_device fails, the release() callback of the video_device structure is *not* called, so the caller is responsible for freeing any data. Usually that means that you call video_device_release() on failure. */ -int __must_check video_register_device(struct video_device *vdev, int type, int nr); +static inline int __must_check video_register_device(struct video_device *vdev, + int type, int nr) +{ + return __video_register_device(vdev, type, nr, 1, vdev->fops->owner); +} /* Same as video_register_device, but no warning is issued if the desired device node number was already in use. */ -int __must_check video_register_device_no_warn(struct video_device *vdev, int type, int nr); +static inline int __must_check video_register_device_no_warn( + struct video_device *vdev, int type, int nr) +{ + return __video_register_device(vdev, type, nr, 0, vdev->fops->owner); +} /* Unregister video devices. Will do nothing if vdev == NULL or video_is_registered() returns false. */ diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h index b16f307d471..78b11e5a6db 100644 --- a/include/media/v4l2-device.h +++ b/include/media/v4l2-device.h @@ -96,6 +96,12 @@ int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, 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); + /* Iterate over all subdevs. */ #define v4l2_device_for_each_subdev(sd, v4l2_dev) \ list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index da16d2f4a00..474ef009fd3 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -22,6 +22,7 @@ #define _V4L2_SUBDEV_H #include <media/v4l2-common.h> +#include <media/v4l2-dev.h> #include <media/v4l2-mediabus.h> /* generic v4l2_device notify callback notification values */ @@ -431,9 +432,11 @@ struct v4l2_subdev_internal_ops { #define V4L2_SUBDEV_NAME_SIZE 32 /* Set this flag if this subdev is a i2c device. */ -#define V4L2_SUBDEV_FL_IS_I2C (1U << 0) +#define V4L2_SUBDEV_FL_IS_I2C (1U << 0) /* Set this flag if this subdev is a spi device. */ -#define V4L2_SUBDEV_FL_IS_SPI (1U << 1) +#define V4L2_SUBDEV_FL_IS_SPI (1U << 1) +/* Set this flag if this subdev needs a device node. */ +#define V4L2_SUBDEV_FL_HAS_DEVNODE (1U << 2) /* Each instance of a subdev driver should create this struct, either stand-alone or embedded in a larger struct. @@ -455,8 +458,15 @@ struct v4l2_subdev { /* pointer to private data */ void *dev_priv; void *host_priv; + /* subdev device node */ + struct video_device devnode; }; +#define vdev_to_v4l2_subdev(vdev) \ + container_of(vdev, struct v4l2_subdev, devnode) + +extern const struct v4l2_file_operations v4l2_subdev_fops; + static inline void v4l2_set_subdevdata(struct v4l2_subdev *sd, void *p) { sd->dev_priv = p; |