Commit 86748f35 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

[media] v4l2-ioctl.c: v4l2-ioctl: add debug and callback/offset functionality 



Add the necessary plumbing to make it possible to replace the switch by a
table driven implementation.

The ioctls ops can either be called directly, or by calling a small function
that does some additional work if needed.

Signed-off-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
parent 27cd2aba

drivers/media/video/v4l2-ioctl.c

+78 −13
Original line number Diff line number Diff line
@@ -396,12 +396,22 @@ struct v4l2_ioctl_info { 
	unsigned int ioctl;

	u32 flags;

	const char * const name;

	union {

		u32 offset;

		int (*func)(const struct v4l2_ioctl_ops *ops,

				struct file *file, void *fh, void *p);

	};

	void (*debug)(const void *arg, bool write_only);

};



/* This control needs a priority check */

#define INFO_FL_PRIO	(1 << 0)

/* This control can be valid if the filehandle passes a control handler. */

#define INFO_FL_CTRL	(1 << 1)

/* This is a standard ioctl, no need for special code */

#define INFO_FL_STD	(1 << 2)

/* This is ioctl has its own function */

#define INFO_FL_FUNC	(1 << 3)

/* Zero struct from after the field to the end */

#define INFO_FL_CLEAR(v4l2_struct, field)			\

	((offsetof(struct v4l2_struct, field) +			\
@@ -414,6 +424,24 @@ struct v4l2_ioctl_info { 
	.name = #_ioctl,					\

}



#define IOCTL_INFO_STD(_ioctl, _vidioc, _debug, _flags)			\

	[_IOC_NR(_ioctl)] = {						\

		.ioctl = _ioctl,					\

		.flags = _flags | INFO_FL_STD,				\

		.name = #_ioctl,					\

		.offset = offsetof(struct v4l2_ioctl_ops, _vidioc),	\

		.debug = _debug,					\

	}



#define IOCTL_INFO_FNC(_ioctl, _func, _debug, _flags)			\

	[_IOC_NR(_ioctl)] = {						\

		.ioctl = _ioctl,					\

		.flags = _flags | INFO_FL_FUNC,				\

		.name = #_ioctl,					\

		.func = _func,						\

		.debug = _debug,					\

	}



static struct v4l2_ioctl_info v4l2_ioctls[] = {

	IOCTL_INFO(VIDIOC_QUERYCAP, 0),

	IOCTL_INFO(VIDIOC_ENUM_FMT, INFO_FL_CLEAR(v4l2_fmtdesc, type)),
@@ -512,7 +540,7 @@ bool v4l2_is_known_ioctl(unsigned int cmd) 
   external ioctl messages as well as internal V4L ioctl */

void v4l_printk_ioctl(unsigned int cmd)

{

	char *dir, *type;

	const char *dir, *type;



	switch (_IOC_TYPE(cmd)) {

	case 'd':
@@ -523,10 +551,11 @@ void v4l_printk_ioctl(unsigned int cmd) 
			type = "v4l2";

			break;

		}

		printk("%s", v4l2_ioctls[_IOC_NR(cmd)].name);

		pr_cont("%s", v4l2_ioctls[_IOC_NR(cmd)].name);

		return;

	default:

		type = "unknown";

		break;

	}



	switch (_IOC_DIR(cmd)) {
@@ -536,7 +565,7 @@ void v4l_printk_ioctl(unsigned int cmd) 
	case _IOC_READ | _IOC_WRITE: dir = "rw"; break;

	default:                     dir = "*ERR*"; break;

	}

	printk("%s ioctl '%c', dir=%s, #%d (0x%08x)",

	pr_cont("%s ioctl '%c', dir=%s, #%d (0x%08x)",

		type, _IOC_TYPE(cmd), dir, _IOC_NR(cmd), cmd);

}

EXPORT_SYMBOL(v4l_printk_ioctl);
@@ -546,6 +575,9 @@ static long __video_do_ioctl(struct file *file, 
{

	struct video_device *vfd = video_devdata(file);

	const struct v4l2_ioctl_ops *ops = vfd->ioctl_ops;

	bool write_only = false;

	struct v4l2_ioctl_info default_info;

	const struct v4l2_ioctl_info *info;

	void *fh = file->private_data;

	struct v4l2_fh *vfh = NULL;

	int use_fh_prio = 0;
@@ -563,23 +595,40 @@ static long __video_do_ioctl(struct file *file, 
	}



	if (v4l2_is_known_ioctl(cmd)) {

		struct v4l2_ioctl_info *info = &v4l2_ioctls[_IOC_NR(cmd)];

		info = &v4l2_ioctls[_IOC_NR(cmd)];



	        if (!test_bit(_IOC_NR(cmd), vfd->valid_ioctls) &&

		    !((info->flags & INFO_FL_CTRL) && vfh && vfh->ctrl_handler))

			return -ENOTTY;

			goto done;



		if (use_fh_prio && (info->flags & INFO_FL_PRIO)) {

			ret = v4l2_prio_check(vfd->prio, vfh->prio);

			if (ret)

				return ret;

				goto done;

		}

	} else {

		default_info.ioctl = cmd;

		default_info.flags = 0;

		default_info.debug = NULL;

		info = &default_info;

	}



	if ((vfd->debug & V4L2_DEBUG_IOCTL) &&

				!(vfd->debug & V4L2_DEBUG_IOCTL_ARG)) {

	write_only = _IOC_DIR(cmd) == _IOC_WRITE;

	if (info->debug && write_only && vfd->debug > V4L2_DEBUG_IOCTL) {

		v4l_print_ioctl(vfd->name, cmd);

		printk(KERN_CONT "\n");

		pr_cont(": ");

		info->debug(arg, write_only);

	}

	if (info->flags & INFO_FL_STD) {

		typedef int (*vidioc_op)(struct file *file, void *fh, void *p);

		const void *p = vfd->ioctl_ops;

		const vidioc_op *vidioc = p + info->offset;



		ret = (*vidioc)(file, fh, arg);

		goto done;

	} else if (info->flags & INFO_FL_FUNC) {

		ret = info->func(ops, file, fh, arg);

		goto done;

	}



	switch (cmd) {
@@ -2101,10 +2150,26 @@ static long __video_do_ioctl(struct file *file, 
		break;

	} /* switch */



	if (vfd->debug & V4L2_DEBUG_IOCTL_ARG) {

		if (ret < 0) {

done:

	if (vfd->debug) {

		if (write_only && vfd->debug > V4L2_DEBUG_IOCTL) {

			if (ret < 0)

				printk(KERN_DEBUG "%s: error %ld\n",

					video_device_node_name(vfd), ret);

			return ret;

		}

		v4l_print_ioctl(vfd->name, cmd);

			printk(KERN_CONT " error %ld\n", ret);

		if (ret < 0)

			pr_cont(": error %ld\n", ret);

		else if (vfd->debug == V4L2_DEBUG_IOCTL)

			pr_cont("\n");

		else if (!info->debug)

			return ret;

		else if (_IOC_DIR(cmd) == _IOC_NONE)

			info->debug(arg, write_only);

		else {

			pr_cont(": ");

			info->debug(arg, write_only);

		}

	}

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