From: Hans Verkuil Date: Sat, 23 Aug 2008 10:48:38 +0000 (-0300) Subject: V4L/DVB (8787): v4l2-dev: cleanups and add video_drvdata helper function X-Git-Tag: v2.6.28-rc1~601^2~240 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=bfa8a273bb91078ea193ab94c717889928f3b925;p=linux-2.6-omap-h63xx.git V4L/DVB (8787): v4l2-dev: cleanups and add video_drvdata helper function Cleanup v4l2-dev.[ch], add/improve comments and add a new helper function: video_drvdata() that can get the private driver data from a file struct. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index ff219df4b72..1ec0a1a8fb7 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -42,6 +42,7 @@ static ssize_t show_index(struct device *cd, struct device_attribute *attr, char *buf) { struct video_device *vfd = container_of(cd, struct video_device, dev); + return sprintf(buf, "%i\n", vfd->index); } @@ -49,6 +50,7 @@ static ssize_t show_name(struct device *cd, struct device_attribute *attr, char *buf) { struct video_device *vfd = container_of(cd, struct video_device, dev); + return sprintf(buf, "%.*s\n", (int)sizeof(vfd->name), vfd->name); } @@ -60,10 +62,7 @@ static struct device_attribute video_device_attrs[] = { struct video_device *video_device_alloc(void) { - struct video_device *vfd; - - vfd = kzalloc(sizeof(*vfd), GFP_KERNEL); - return vfd; + return kzalloc(sizeof(struct video_device), GFP_KERNEL); } EXPORT_SYMBOL(video_device_alloc); @@ -263,7 +262,7 @@ int video_register_device_index(struct video_device *vfd, int type, int nr, /* pick a minor number */ mutex_lock(&videodev_lock); - if (nr >= 0 && nr < end-base) { + if (nr >= 0 && nr < end-base) { /* use the one the driver asked for */ i = base + nr; if (NULL != video_device[i]) { @@ -295,7 +294,7 @@ int video_register_device_index(struct video_device *vfd, int type, int nr, } /* sysfs class */ - memset(&vfd->dev, 0x00, sizeof(vfd->dev)); + memset(&vfd->dev, 0, sizeof(vfd->dev)); vfd->dev.class = &video_class; vfd->dev.devt = MKDEV(VIDEO_MAJOR, vfd->minor); if (vfd->parent) @@ -312,8 +311,8 @@ int video_register_device_index(struct video_device *vfd, int type, int nr, fail_minor: mutex_lock(&videodev_lock); video_device[vfd->minor] = NULL; - vfd->minor = -1; mutex_unlock(&videodev_lock); + vfd->minor = -1; return ret; } EXPORT_SYMBOL(video_register_device_index); diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h index 1d4df571060..fb92e3d22d7 100644 --- a/include/media/v4l2-dev.h +++ b/include/media/v4l2-dev.h @@ -9,16 +9,14 @@ #ifndef _V4L2_DEV_H #define _V4L2_DEV_H -#define OBSOLETE_DEVDATA 1 /* to be removed soon */ - #include #include #include #include -#include /* need __user */ #include #define VIDEO_MAJOR 81 + /* Minor device allocation */ #define MINOR_VFL_TYPE_GRABBER_MIN 0 #define MINOR_VFL_TYPE_GRABBER_MAX 63 @@ -71,20 +69,25 @@ struct video_device const struct v4l2_ioctl_ops *ioctl_ops; }; -/* Class-dev to video-device */ +/* dev to video-device */ #define to_video_device(cd) container_of(cd, struct video_device, dev) -/* Version 2 functions */ +/* Register and unregister 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 *vfd, int type, int nr); -int __must_check video_register_device_index(struct video_device *vfd, int type, int nr, - int index); -void video_unregister_device(struct video_device *); +int __must_check video_register_device_index(struct video_device *vfd, + int type, int nr, int index); +void video_unregister_device(struct video_device *vfd); -/* helper functions to alloc / release struct video_device, the - later can be used for video_device->release() */ +/* helper functions to alloc/release struct video_device, the + latter can also be used for video_device->release(). */ struct video_device * __must_check video_device_alloc(void); + /* this release function frees the vfd pointer */ void video_device_release(struct video_device *vfd); + /* this release function does nothing, use when the video_device is a static global struct. Note that having a static video_device is a dubious construction at best. */ @@ -101,9 +104,13 @@ static inline void video_set_drvdata(struct video_device *dev, void *data) dev_set_drvdata(&dev->dev, data); } -#ifdef OBSOLETE_DEVDATA /* to be removed soon */ -/* Obsolete stuff - Still needed for radio devices and obsolete drivers */ -extern struct video_device* video_devdata(struct file*); -#endif +struct video_device *video_devdata(struct file *file); + +/* Combine video_get_drvdata and video_devdata as this is + used very often. */ +static inline void *video_drvdata(struct file *file) +{ + return video_get_drvdata(video_devdata(file)); +} #endif /* _V4L2_DEV_H */