Hi, I've updated the videodev patch set. The core part of the redesign is attached below for comments. It is also available here: http://bytesex.org/patches/2.5/10_videodev-2.5.6-pre2.diff The 2.4 version of the patch (which is slightly different because it keeps the old stuff for backward compatibility) is here: http://bytesex.org/patches/10_videodev-2.4.19-pre2.diff I've also updated most v4l drivers (including usb cams this time) to the new videodev interface. Changes are available as individual, per driver patches from: http://bytesex.org/patches/2.5/ There is also one big patch with all changes: http://bytesex.org/patches/2.5/patch-2.5.6-pre2-kraxel.gz Comments? Bugs? I plan to feed this to Linus soon ... Gerd ==============================[ cut here ]============================== This patch is a redesign for videodev.[ch]. Changes: - drop the function pointers (read/write/mmap/poll/...) from struct video_device, use struct file_operations directly instead. Dispatching to different drivers by minor number is done the same way soundcore.o handles this: swap file->f_fops at open() time. - also drop the now obsolete video_red/write/mmap/poll/... functions from videodev.c - provide a video_generic_ioctl() function which can (and should) be used by v4l drivers to handle copying from and to userspace. - provide video_exclusive_open/release functions which can be used by v4l drivers to make sure only one process at a time opens the device. They can be hooked directly into struct file_operations if some driver has nothing to initialize at open time (which is true for many drivers in drivers/media/radio/). --- linux-2.5.6-pre2/drivers/media/video/videodev.c Fri Mar 1 20:00:52 2002 +++ linux/drivers/media/video/videodev.c Fri Mar 1 20:01:31 2002 @@ -25,15 +25,13 @@ #include <linux/mm.h> #include <linux/string.h> #include <linux/errno.h> -#include <linux/videodev.h> #include <linux/init.h> - +#include <linux/kmod.h> #include <asm/uaccess.h> #include <asm/system.h> #include <asm/semaphore.h> -#include <linux/kmod.h> - +#include <linux/videodev.h> #define VIDEO_NUM_DEVICES 256 @@ -62,61 +60,20 @@ #endif /* CONFIG_PROC_FS && CONFIG_VIDEO_PROC_FS */ - -/* - * Read will do some smarts later on. Buffer pin etc. - */ - -static ssize_t video_read(struct file *file, - char *buf, size_t count, loff_t *ppos) -{ - struct video_device *vfl=video_device[minor(file->f_dentry->d_inode->i_rdev)]; - if(vfl->read) - return vfl->read(vfl, buf, count, file->f_flags&O_NONBLOCK); - else - return -EINVAL; -} - - -/* - * Write for now does nothing. No reason it shouldnt do overlay setting - * for some boards I guess.. - */ - -static ssize_t video_write(struct file *file, const char *buf, - size_t count, loff_t *ppos) -{ - struct video_device *vfl=video_device[minor(file->f_dentry->d_inode->i_rdev)]; - if(vfl->write) - return vfl->write(vfl, buf, count, file->f_flags&O_NONBLOCK); - else - return 0; -} - -/* - * Poll to see if we're readable, can probably be used for timing on incoming - * frames, etc.. - */ - -static unsigned int video_poll(struct file *file, poll_table * wait) +struct video_device* video_devdata(struct file *file) { - struct video_device *vfl=video_device[minor(file->f_dentry->d_inode->i_rdev)]; - if(vfl->poll) - return vfl->poll(vfl, file, wait); - else - return 0; + return video_device[minor(file->f_dentry->d_inode->i_rdev)]; } - /* * Open a video device. */ - static int video_open(struct inode *inode, struct file *file) { unsigned int minor = minor(inode->i_rdev); - int err, retval = 0; + int err = 0; struct video_device *vfl; + struct file_operations *old_fops; if(minor>=VIDEO_NUM_DEVICES) return -ENODEV; @@ -129,88 +86,115 @@ request_module(modname); vfl=video_device[minor]; if (vfl==NULL) { - retval = -ENODEV; + err = -ENODEV; goto error_out; } } - if(vfl->busy) { - retval = -EBUSY; - goto error_out; + unlock_kernel(); + + old_fops = file->f_op; + file->f_op = fops_get(vfl->fops); + if(file->f_op->open) + err = file->f_op->open(inode,file); + if (err) { + fops_put(file->f_op); + file->f_op = fops_get(old_fops); } - vfl->busy=1; /* In case vfl->open sleeps */ - - if(vfl->owner) - __MOD_INC_USE_COUNT(vfl->owner); + fops_put(old_fops); + return err; - if(vfl->open) - { - err=vfl->open(vfl,0); /* Tell the device it is open */ - if(err) - { - vfl->busy=0; - if(vfl->owner) - __MOD_DEC_USE_COUNT(vfl->owner); - - unlock_kernel(); - return err; - } - } - unlock_kernel(); - return 0; error_out: unlock_kernel(); - return retval; + return err; } /* - * Last close of a video for Linux device + * ioctl helper function -- handles userspace copying */ +int +video_generic_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct video_device *vfl = video_devdata(file); + char sbuf[128]; + void *mbuf = NULL; + void *parg = NULL; + int err = -EINVAL; -static int video_release(struct inode *inode, struct file *file) -{ - struct video_device *vfl; - lock_kernel(); - vfl=video_device[minor(inode->i_rdev)]; - if(vfl->close) - vfl->close(vfl); - vfl->busy=0; - if(vfl->owner) - __MOD_DEC_USE_COUNT(vfl->owner); - unlock_kernel(); - return 0; -} + if (vfl->kernel_ioctl == NULL) + return -EINVAL; -static int video_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg) -{ - struct video_device *vfl=video_device[minor(inode->i_rdev)]; - int err=vfl->ioctl(vfl, cmd, (void *)arg); + /* Copy arguments into temp kernel buffer */ + switch (_IOC_DIR(cmd)) { + case _IOC_NONE: + parg = (void *)arg; + break; + case _IOC_READ: /* some v4l ioctls are marked wrong ... */ + case _IOC_WRITE: + case (_IOC_WRITE | _IOC_READ): + if (_IOC_SIZE(cmd) <= sizeof(sbuf)) { + parg = sbuf; + } else { + /* too big to allocate from stack */ + mbuf = kmalloc(_IOC_SIZE(cmd),GFP_KERNEL); + if (NULL == mbuf) + return -ENOMEM; + parg = mbuf; + } + + err = -EFAULT; + if (copy_from_user(parg, (void *)arg, _IOC_SIZE(cmd))) + goto out; + break; + } - if(err!=-ENOIOCTLCMD) - return err; - - switch(cmd) + /* call driver */ + err = vfl->kernel_ioctl(inode, file, cmd, parg); + if (err == -ENOIOCTLCMD) + err = -EINVAL; + if (err < 0) + goto out; + + /* Copy results into user buffer */ + switch (_IOC_DIR(cmd)) { - default: - return -EINVAL; + case _IOC_READ: + case (_IOC_WRITE | _IOC_READ): + if (copy_to_user((void *)arg, parg, _IOC_SIZE(cmd))) + err = -EFAULT; + break; } + +out: + if (mbuf) + kfree(mbuf); + return err; } /* - * We need to do MMAP support + * open/release helper functions -- handle exclusive opens */ - -int video_mmap(struct file *file, struct vm_area_struct *vma) +extern int video_exclusive_open(struct inode *inode, struct file *file) { - int ret = -EINVAL; - struct video_device *vfl=video_device[minor(file->f_dentry->d_inode->i_rdev)]; - if(vfl->mmap) { - lock_kernel(); - ret = vfl->mmap(vma, vfl, (char *)vma->vm_start, - (unsigned long)(vma->vm_end-vma->vm_start)); - unlock_kernel(); + struct video_device *vfl = video_devdata(file); + int retval = 0; + + down(&vfl->lock); + if (vfl->users) { + retval = -EBUSY; + } else { + vfl->users++; } - return ret; + up(&vfl->lock); + return retval; +} + +extern int video_exclusive_release(struct inode *inode, struct file *file) +{ + struct video_device *vfl = video_devdata(file); + + vfl->users--; + return 0; } /* @@ -398,7 +382,6 @@ { int i=0; int base; - int err; int end; char *name_base; char name[16]; @@ -452,17 +435,7 @@ vfd->minor=i; up(&videodev_register_lock); - /* The init call may sleep so we book the slot out - then call */ MOD_INC_USE_COUNT; - if(vfd->initialize) { - err=vfd->initialize(vfd); - if(err<0) { - video_device[i]=NULL; - MOD_DEC_USE_COUNT; - return err; - } - } sprintf (name, "v4l/%s%d", name_base, i - base); /* * Start the device root only. Anything else @@ -474,6 +447,7 @@ S_IFCHR | S_IRUSR | S_IWUSR, &video_fops, NULL); + init_MUTEX(&vfd->lock); #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS) sprintf (name, "%s%d", name_base, i - base); @@ -509,13 +483,7 @@ { owner: THIS_MODULE, llseek: no_llseek, - read: video_read, - write: video_write, - ioctl: video_ioctl, - mmap: video_mmap, open: video_open, - release: video_release, - poll: video_poll, }; /* @@ -540,12 +508,9 @@ static void __exit videodev_exit(void) { -#ifdef MODULE #if defined(CONFIG_PROC_FS) && defined(CONFIG_VIDEO_PROC_FS) videodev_proc_destroy (); #endif -#endif - devfs_unregister_chrdev(VIDEO_MAJOR, "video_capture"); } @@ -554,6 +519,10 @@ EXPORT_SYMBOL(video_register_device); EXPORT_SYMBOL(video_unregister_device); +EXPORT_SYMBOL(video_devdata); +EXPORT_SYMBOL(video_generic_ioctl); +EXPORT_SYMBOL(video_exclusive_open); +EXPORT_SYMBOL(video_exclusive_release); MODULE_AUTHOR("Alan Cox"); MODULE_DESCRIPTION("Device registrar for Video4Linux drivers"); --- linux-2.5.6-pre2/include/linux/videodev.h Fri Mar 1 20:00:56 2002 +++ linux/include/linux/videodev.h Fri Mar 1 20:13:34 2002 @@ -4,6 +4,18 @@ #include <linux/types.h> #include <linux/version.h> +#if 0 +/* + * v4l2 is still work-in-progress, integration planed for 2.5.x + * v4l2 project homepage: http://www.thedirks.org/v4l2/ + * patches available from: http://bytesex.org/patches/ + */ +# define HAVE_V4L2 1 +# include <linux/videodev2.h> +#else +# undef HAVE_V4L2 +#endif + #ifdef __KERNEL__ #include <linux/poll.h> @@ -13,24 +25,25 @@ struct video_device { struct module *owner; - char name[32]; - int type; + char name[32]; + int type; /* v4l1 */ + int type2; /* v4l2 */ int hardware; + int minor; - int (*open)(struct video_device *, int mode); - void (*close)(struct video_device *); - long (*read)(struct video_device *, char *, unsigned long, int noblock); - /* Do we need a write method ? */ - long (*write)(struct video_device *, const char *, unsigned long, int noblock); -#if LINUX_VERSION_CODE >= 0x020100 - unsigned int (*poll)(struct video_device *, struct file *, poll_table *); -#endif - int (*ioctl)(struct video_device *, unsigned int , void *); - int (*mmap)(struct vm_area_struct *vma, struct video_device *, const char *, unsigned long); - int (*initialize)(struct video_device *); + /* new interface -- we will use file_operations directly + * like soundcore does. + * kernel_ioctl() will be called by video_generic_ioctl. + * video_generic_ioctl() does the userspace copying of the + * ioctl arguments */ + struct file_operations *fops; + int (*kernel_ioctl)(struct inode *inode, struct file *file, + unsigned int cmd, void *arg); void *priv; /* Used to be 'private' but that upsets C++ */ - int busy; - int minor; + + /* for videodev.c intenal usage -- don't touch */ + int users; + struct semaphore lock; devfs_handle_t devfs_handle; }; @@ -43,8 +56,13 @@ #define VFL_TYPE_VTX 3 extern void video_unregister_device(struct video_device *); -#endif +extern struct video_device* video_devdata(struct file*); +extern int video_exclusive_open(struct inode *inode, struct file *file); +extern int video_exclusive_release(struct inode *inode, struct file *file); +extern int video_generic_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg); +#endif /* __KERNEL__ */ #define VID_TYPE_CAPTURE 1 /* Can capture */ #define VID_TYPE_TUNER 2 /* Can tune */ @@ -150,6 +168,7 @@ #define VIDEO_AUDIO_VOLUME 4 #define VIDEO_AUDIO_BASS 8 #define VIDEO_AUDIO_TREBLE 16 +#define VIDEO_AUDIO_BALANCE 32 char name[16]; #define VIDEO_SOUND_MONO 1 #define VIDEO_SOUND_STEREO 2 @@ -379,4 +398,10 @@ #define VID_HARDWARE_MEYE 32 /* Sony Vaio MotionEye cameras */ #define VID_HARDWARE_CPIA2 33 -#endif +#endif /* __LINUX_VIDEODEV_H */ + +/* + * Local variables: + * c-basic-offset: 8 + * End: + */
