path: root/system/v4l2loopback/update_to_master_17JUN2020.patch

diff --git a/README.md b/README.md
index d8b295a..d8d338b 100644
--- a/README.md
+++ b/README.md
@@ -18,9 +18,31 @@ only be of limited use...
 
 # ISSUES
 for current issues, checkout https://github.com/umlaeute/v4l2loopback/issues
-please use the issue-tracker for reporting any problems
+please use the issue-tracker for reporting any problems.
+
+before you create a new ticket in our issue tracker, please make sure that you have read
+*this* document and followed any instructions found within.
+
+also, please search the issue-tracker *before* reporting any problems: it's much better
+to add your information to an existing ticket than to create a new ticket with essentially
+the same information.
+
+## SEEKING HELP
+the issue tracker is meant to track specific bugs in the code (and new features).
+however, it is ill-suited as a user support forum.
+
+if you have general questions or problems, please use the `v4l2loopback` tag
+on [Stack Overflow](https://stackoverflow.com/questions/tagged/v4l2loopback) instead:
+https://stackoverflow.com/questions/tagged/v4l2loopback
+
 
 # DEPENDENCIES
+in order to build (compile,...) anything, you must have a *working* build-environment
+(compiler, GNU make,...).
+the kernel can be somewhat picky if you try to load a module that was compiled with
+a different compiler than was used to compile the kernel itself.
+so make sure to have the right compiler in place.
+
 the v4l2loopback module is a *kernel module*.
 in order to build it, you *must have* the kernel headers installed that match
 the linux kernel with which you want to use the module (in most cases this will
@@ -31,6 +53,12 @@ the first few number are the same.
 (modules will be incompatible if the versions don't match. if you are lucky, the module will
 simply refuse to load. if you are unlucky, your computer will spit in your eye or do worse.)
 
+there are distribution-specific differences on how to get the correct kernel headers
+(or to install a compilation toolchain).
+documenting all those possibilities would go far beyond the scope of `v4l2loopback`.
+please understnd that we cannot provide support for questions regarding dependencies.
+
+
 # BUILD
 to build the kernel module run:
 
diff --git a/v4l2loopback.c b/v4l2loopback.c
index bcf7667..b0f7b93 100644
--- a/v4l2loopback.c
+++ b/v4l2loopback.c
@@ -48,9 +48,9 @@
 
 MODULE_DESCRIPTION("V4L2 loopback video device");
 MODULE_AUTHOR("Vasily Levin, " \
-              "IOhannes m zmoelnig <zmoelnig@iem.at>,"  \
-              "Stefan Diewald,"                         \
-              "Anton Novikov"                           \
+	      "IOhannes m zmoelnig <zmoelnig@iem.at>,"	\
+	      "Stefan Diewald,"				\
+	      "Anton Novikov"				\
 	      "et al."					\
 		);
 MODULE_LICENSE("GPL");
@@ -61,18 +61,18 @@ MODULE_LICENSE("GPL");
 #define STRINGIFY(s) #s
 #define STRINGIFY2(s) STRINGIFY(s)
 
-#define dprintk(fmt, args...)                                           \
-	do { if (debug > 0) {                                                 \
+#define dprintk(fmt, args...)						\
+	do { if (debug > 0) {						\
 		printk(KERN_INFO "v4l2-loopback[" STRINGIFY2(__LINE__) "]: " fmt, ##args); \
 	} } while (0)
 
-#define MARK()                                                          \
-	do { if (debug > 1) {                                                  \
+#define MARK()								\
+	do { if (debug > 1) {						\
 		printk(KERN_INFO "%s:%d[%s]\n", __FILE__, __LINE__, __func__);	\
 	} } while (0)
 
-#define dprintkrw(fmt, args...)                                         \
-	do { if (debug > 2) {                                                 \
+#define dprintkrw(fmt, args...)						\
+	do { if (debug > 2) {						\
 		printk(KERN_INFO "v4l2-loopback[" STRINGIFY2(__LINE__)"]: " fmt, ##args); \
 	} } while (0)
 
@@ -85,14 +85,14 @@ struct v4l2_ctrl_handler {
 	int error;
 };
 struct v4l2_ctrl_config {
-        void *ops;
-        u32 id;
+	void *ops;
+	u32 id;
 	const char *name;
 	int type;
-        s32 min;
-        s32 max;
-        u32 step;
-        s32 def;
+	s32 min;
+	s32 max;
+	u32 step;
+	s32 def;
 };
 int v4l2_ctrl_handler_init(struct v4l2_ctrl_handler*hdl,
 			   unsigned nr_of_controls_hint)
@@ -119,7 +119,7 @@ struct v4l2_device {
 	char name[V4L2_DEVICE_NAME_SIZE];
 	struct v4l2_ctrl_handler*ctrl_handler;
 };
-static inline int  v4l2_device_register  (void *dev, void *v4l2_dev) { return 0; }
+static inline int  v4l2_device_register(void *dev, void *v4l2_dev) { return 0; }
 static inline void v4l2_device_unregister(struct v4l2_device *v4l2_dev) { return; }
 #endif /*  HAVE__V4L2_DEVICE */
 
@@ -155,7 +155,7 @@ static inline void v4l2l_get_timestamp(struct v4l2_buffer *b) {
 
 /* module constants
  *  can be overridden during he build process using something like
- *      make KCPPFLAGS="-DMAX_DEVICES=100"
+ *	make KCPPFLAGS="-DMAX_DEVICES=100"
  */
 
 
@@ -235,13 +235,13 @@ MODULE_PARM_DESC(max_height, "maximum frame height");
 
 /* control IDs */
 #ifndef HAVE__V4L2_CTRLS
-# define V4L2LOOPBACK_CID_BASE  (V4L2_CID_PRIVATE_BASE)
+# define V4L2LOOPBACK_CID_BASE	(V4L2_CID_PRIVATE_BASE)
 #else
-# define V4L2LOOPBACK_CID_BASE  (V4L2_CID_USER_BASE | 0xf000)
+# define V4L2LOOPBACK_CID_BASE	(V4L2_CID_USER_BASE | 0xf000)
 #endif
-#define CID_KEEP_FORMAT        (V4L2LOOPBACK_CID_BASE + 0)
+#define CID_KEEP_FORMAT	       (V4L2LOOPBACK_CID_BASE + 0)
 #define CID_SUSTAIN_FRAMERATE  (V4L2LOOPBACK_CID_BASE + 1)
-#define CID_TIMEOUT            (V4L2LOOPBACK_CID_BASE + 2)
+#define CID_TIMEOUT	       (V4L2LOOPBACK_CID_BASE + 2)
 #define CID_TIMEOUT_IMAGE_IO   (V4L2LOOPBACK_CID_BASE + 3)
 
 static int v4l2loopback_s_ctrl(struct v4l2_ctrl *ctrl);
@@ -249,44 +249,44 @@ static const struct v4l2_ctrl_ops v4l2loopback_ctrl_ops = {
 	.s_ctrl = v4l2loopback_s_ctrl,
 };
 static const struct v4l2_ctrl_config v4l2loopback_ctrl_keepformat = {
-        .ops = &v4l2loopback_ctrl_ops,
-        .id = CID_KEEP_FORMAT,
-        .name = "keep_format",
-        .type = V4L2_CTRL_TYPE_BOOLEAN,
-        .min = 0,
-        .max = 1,
-        .step = 1,
-        .def = 0,
+	.ops = &v4l2loopback_ctrl_ops,
+	.id = CID_KEEP_FORMAT,
+	.name = "keep_format",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = 0,
+	.max = 1,
+	.step = 1,
+	.def = 0,
 };
 static const struct v4l2_ctrl_config v4l2loopback_ctrl_sustainframerate = {
-        .ops = &v4l2loopback_ctrl_ops,
-        .id = CID_SUSTAIN_FRAMERATE,
-        .name = "sustain_framerate",
-        .type = V4L2_CTRL_TYPE_BOOLEAN,
-        .min = 0,
-        .max = 1,
-        .step = 1,
-        .def = 0,
+	.ops = &v4l2loopback_ctrl_ops,
+	.id = CID_SUSTAIN_FRAMERATE,
+	.name = "sustain_framerate",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = 0,
+	.max = 1,
+	.step = 1,
+	.def = 0,
 };
 static const struct v4l2_ctrl_config v4l2loopback_ctrl_timeout = {
-        .ops = &v4l2loopback_ctrl_ops,
-        .id = CID_TIMEOUT,
-        .name = "timeout",
-        .type = V4L2_CTRL_TYPE_INTEGER,
-        .min = 0,
-        .max = MAX_TIMEOUT,
-        .step = 1,
-        .def = 0,
+	.ops = &v4l2loopback_ctrl_ops,
+	.id = CID_TIMEOUT,
+	.name = "timeout",
+	.type = V4L2_CTRL_TYPE_INTEGER,
+	.min = 0,
+	.max = MAX_TIMEOUT,
+	.step = 1,
+	.def = 0,
 };
 static const struct v4l2_ctrl_config v4l2loopback_ctrl_timeoutimageio = {
-        .ops = &v4l2loopback_ctrl_ops,
-        .id = CID_TIMEOUT_IMAGE_IO,
-        .name = "timeout_image_io",
-        .type = V4L2_CTRL_TYPE_BOOLEAN,
-        .min = 0,
-        .max = 1,
-        .step = 1,
-        .def = 0,
+	.ops = &v4l2loopback_ctrl_ops,
+	.id = CID_TIMEOUT_IMAGE_IO,
+	.name = "timeout_image_io",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = 0,
+	.max = 1,
+	.step = 1,
+	.def = 0,
 };
 
 
@@ -321,7 +321,7 @@ struct v4l2_loopback_device {
 				  (close to) nominal framerate */
 
 	/* buffers stuff */
-	u8 *image;         /* pointer to actual buffers data */
+	u8 *image;	   /* pointer to actual buffers data */
 	unsigned long int imagesize;  /* size of buffers data */
 	int buffers_number;  /* should not be big, 4 is a good choice */
 	struct v4l2l_buffer buffers[MAX_BUFFERS];	/* inner driver buffers */
@@ -386,13 +386,13 @@ struct v4l2_loopback_opener {
 /* this is heavily inspired by the bttv driver found in the linux kernel */
 struct v4l2l_format {
 	char *name;
-	int  fourcc;          /* video4linux 2      */
-	int  depth;           /* bit/pixel          */
+	int  fourcc;	      /* video4linux 2	    */
+	int  depth;	      /* bit/pixel	    */
 	int  flags;
 };
 /* set the v4l2l_format.flags to PLANAR for non-packed formats */
-#define FORMAT_FLAGS_PLANAR       0x01
-#define FORMAT_FLAGS_COMPRESSED   0x02
+#define FORMAT_FLAGS_PLANAR	  0x01
+#define FORMAT_FLAGS_COMPRESSED	  0x02
 
 #ifndef V4L2_PIX_FMT_VP9
 #define V4L2_PIX_FMT_VP9  v4l2_fourcc('V', 'P', '9', '0')
@@ -446,7 +446,7 @@ static void pix_format_set_size(struct v4l2_pix_format *f,
 		f->bytesperline = width; /* Y plane */
 		f->sizeimage = (width * height * fmt->depth) >> 3;
 	} else if (fmt->flags & FORMAT_FLAGS_COMPRESSED) {
-	        /* doesn't make sense for compressed formats */
+		/* doesn't make sense for compressed formats */
 		f->bytesperline = 0;
 		f->sizeimage = (width * height * fmt->depth) >> 3;
 	} else {
@@ -458,7 +458,7 @@ static void pix_format_set_size(struct v4l2_pix_format *f,
 static int set_timeperframe(struct v4l2_loopback_device *dev,
 		struct v4l2_fract *tpf)
 {
-        if((tpf->denominator < 1) || (tpf->numerator < 1)) {
+	if((tpf->denominator < 1) || (tpf->numerator < 1)) {
 	  return -EINVAL;
 	}
 	dev->capture_param.timeperframe = *tpf;
@@ -485,7 +485,7 @@ static ssize_t attr_show_format(struct device *cd,
 	tpf = &dev->capture_param.timeperframe;
 
 	fourcc2str(dev->pix_format.pixelformat, buf4cc);
-        buf4cc[4]=0;
+	buf4cc[4]=0;
 	if (tpf->numerator == 1)
 		snprintf(buf_fps, sizeof(buf_fps), "%d", tpf->denominator);
 	else
@@ -578,7 +578,7 @@ static void v4l2loopback_create_sysfs(struct video_device *vdev)
 {
 	int res = 0;
 
-#define V4L2_SYSFS_CREATE(x)     res = device_create_file(&vdev->dev, &dev_attr_##x); if (res < 0) break
+#define V4L2_SYSFS_CREATE(x)	 res = device_create_file(&vdev->dev, &dev_attr_##x); if (res < 0) break
 	if (!vdev)
 		return;
 	do {
@@ -671,7 +671,7 @@ static int vidioc_querycap(struct file *file, void *priv, struct v4l2_capability
 {
 	struct v4l2_loopback_device *dev = v4l2loopback_getdevice(file);
 	int devnr = ((struct v4l2loopback_private *)video_get_drvdata(dev->vdev))->devicenr;
-        __u32 capabilities = V4L2_CAP_STREAMING | V4L2_CAP_READWRITE;
+	__u32 capabilities = V4L2_CAP_STREAMING | V4L2_CAP_READWRITE;
 
 	strlcpy(cap->driver, "v4l2 loopback", sizeof(cap->driver));
 	vidioc_fill_name(cap->card, sizeof(cap->card), devnr);
@@ -698,7 +698,10 @@ static int vidioc_querycap(struct file *file, void *priv, struct v4l2_capability
 		}
 	}
 
-	dev->vdev->device_caps = cap->device_caps = cap->capabilities = capabilities;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 7, 0)
+	dev->vdev->device_caps =
+#endif /* >=linux-4.7.0 */
+	cap->device_caps = cap->capabilities = capabilities;
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 3, 0)
 	cap->capabilities |= V4L2_CAP_DEVICE_CAPS;
@@ -891,7 +894,7 @@ static int vidioc_enum_fmt_out(struct file *file, void *fh, struct v4l2_fmtdesc
 		f->pixelformat = dev->pix_format.pixelformat;
 	} else {
 		/* fill in a dummy format */
-                /* coverity[unsigned_compare] */
+		/* coverity[unsigned_compare] */
 		if (f->index < 0 || f->index >= FORMATS)
 			return -EINVAL;
 
@@ -1069,11 +1072,11 @@ static int vidioc_s_parm(struct file *file, void *priv, struct v4l2_streamparm *
 
 	switch (parm->type) {
 	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
-                if ((err=set_timeperframe(dev, &parm->parm.capture.timeperframe)) < 0)
+		if ((err=set_timeperframe(dev, &parm->parm.capture.timeperframe)) < 0)
 		  return err;
 		break;
 	case V4L2_BUF_TYPE_VIDEO_OUTPUT:
-                if ((err=set_timeperframe(dev, &parm->parm.capture.timeperframe)) < 0)
+		if ((err=set_timeperframe(dev, &parm->parm.capture.timeperframe)) < 0)
 		  return err;
 		break;
 	default:
@@ -1249,7 +1252,7 @@ static int vidioc_enum_output(struct file *file, void *fh, struct v4l2_output *o
 	struct v4l2_loopback_device *dev = v4l2loopback_getdevice(file);
 	MARK();
 
-        if (!dev->announce_all_caps && !dev->ready_for_output)
+	if (!dev->announce_all_caps && !dev->ready_for_output)
 		return -ENOTTY;
 
 	if (0 != index)
@@ -1279,7 +1282,7 @@ static int vidioc_enum_output(struct file *file, void *fh, struct v4l2_output *o
 static int vidioc_g_output(struct file *file, void *fh, unsigned int *i)
 {
 	struct v4l2_loopback_device *dev = v4l2loopback_getdevice(file);
-        if (!dev->announce_all_caps && !dev->ready_for_output)
+	if (!dev->announce_all_caps && !dev->ready_for_output)
 		return -ENOTTY;
 	if (i)
 		*i = 0;
@@ -1292,7 +1295,7 @@ static int vidioc_g_output(struct file *file, void *fh, unsigned int *i)
 static int vidioc_s_output(struct file *file, void *fh, unsigned int i)
 {
 	struct v4l2_loopback_device *dev = v4l2loopback_getdevice(file);
-        if (!dev->announce_all_caps && !dev->ready_for_output)
+	if (!dev->announce_all_caps && !dev->ready_for_output)
 		return -ENOTTY;
 
 	if (i)
@@ -1340,7 +1343,7 @@ static int vidioc_enum_input(struct file *file, void *fh, struct v4l2_input *inp
 static int vidioc_g_input(struct file *file, void *fh, unsigned int *i)
 {
 	struct v4l2_loopback_device *dev = v4l2loopback_getdevice(file);
-        if (!dev->announce_all_caps && !dev->ready_for_capture)
+	if (!dev->announce_all_caps && !dev->ready_for_capture)
 		return -ENOTTY;
 	if (i)
 		*i = 0;
@@ -1353,7 +1356,7 @@ static int vidioc_g_input(struct file *file, void *fh, unsigned int *i)
 static int vidioc_s_input(struct file *file, void *fh, unsigned int i)
 {
 	struct v4l2_loopback_device *dev = v4l2loopback_getdevice(file);
-        if (!dev->announce_all_caps && !dev->ready_for_capture)
+	if (!dev->announce_all_caps && !dev->ready_for_capture)
 		return -ENOTTY;
 	if (i == 0)
 		return 0;
@@ -1527,7 +1530,7 @@ static int vidioc_qbuf(struct file *file, void *private_data, struct v4l2_buffer
 		/*  Hopefully fix 'DQBUF return bad index if queue bigger then 2 for capture'
 			https://github.com/umlaeute/v4l2loopback/issues/60 */
 		buf->flags &= ~V4L2_BUF_FLAG_DONE;
-	        buf->flags |= V4L2_BUF_FLAG_QUEUED;
+		buf->flags |= V4L2_BUF_FLAG_QUEUED;
 
 		wake_up_all(&dev->read_event);
 		return 0;
@@ -1666,7 +1669,7 @@ static int vidioc_streamon(struct file *file, void *private_data, enum v4l2_buf_
 	default:
 		return -EINVAL;
 	}
-        return -EINVAL;
+	return -EINVAL;
 }
 
 /* stop streaming
@@ -1896,8 +1899,8 @@ static ssize_t v4l2_loopback_read(struct file *file,
 	dev    = v4l2loopback_getdevice(file);
 
 	read_index = get_capture_buffer(file);
-        if (read_index < 0)
-          return read_index;
+	if (read_index < 0)
+	  return read_index;
 	if (count > dev->buffer_size)
 		count = dev->buffer_size;
 	b = &dev->buffers[read_index].buffer;
@@ -2034,20 +2037,20 @@ static void init_buffers(struct v4l2_loopback_device *dev)
 
 	for (i = 0; i < dev->buffers_number; ++i) {
 		struct v4l2_buffer *b = &dev->buffers[i].buffer;
-		b->index             = i;
-		b->bytesused         = bytesused;
-		b->length            = buffer_size;
-		b->field             = V4L2_FIELD_NONE;
-		b->flags             = 0;
+		b->index	     = i;
+		b->bytesused	     = bytesused;
+		b->length	     = buffer_size;
+		b->field	     = V4L2_FIELD_NONE;
+		b->flags	     = 0;
 #if LINUX_VERSION_CODE < KERNEL_VERSION(3, 6, 1)
-		b->input             = 0;
+		b->input	     = 0;
 #endif
-		b->m.offset          = i * buffer_size;
-		b->memory            = V4L2_MEMORY_MMAP;
-		b->sequence          = 0;
+		b->m.offset	     = i * buffer_size;
+		b->memory	     = V4L2_MEMORY_MMAP;
+		b->sequence	     = 0;
 		b->timestamp.tv_sec  = 0;
 		b->timestamp.tv_usec = 0;
-		b->type              = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+		b->type		     = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 
 		v4l2l_get_timestamp(b);
 	}
@@ -2077,29 +2080,29 @@ static void init_vdev(struct video_device *vdev, int nr)
 	vidioc_fill_name(vdev->name, sizeof(vdev->name), nr);
 
 #ifdef V4L2LOOPBACK_WITH_STD
-	vdev->tvnorms      = V4L2_STD_ALL;
+	vdev->tvnorms	   = V4L2_STD_ALL;
 #endif /* V4L2LOOPBACK_WITH_STD */
 
-	vdev->vfl_type     = VFL_TYPE_VIDEO;
-	vdev->fops         = &v4l2_loopback_fops;
-	vdev->ioctl_ops    = &v4l2_loopback_ioctl_ops;
-	vdev->release      = &video_device_release;
-	vdev->minor        = -1;
+	vdev->vfl_type	   = VFL_TYPE_VIDEO;
+	vdev->fops	   = &v4l2_loopback_fops;
+	vdev->ioctl_ops	   = &v4l2_loopback_ioctl_ops;
+	vdev->release	   = &video_device_release;
+	vdev->minor	   = -1;
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 7, 0)
 	vdev->device_caps  =
-		V4L2_CAP_DEVICE_CAPS |
+		V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT |
+		V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
 #ifdef V4L2_CAP_VIDEO_M2M
-		V4L2_CAP_VIDEO_M2M |
-#endif
-                V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT |
-                V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
+	vdev->device_caps  |= V4L2_CAP_VIDEO_M2M;
 #endif
+#endif /* >=linux-4.7.0 */
+
 	if (debug > 1)
-		#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 20, 0)
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 20, 0)
 			vdev->debug = V4L2_DEBUG_IOCTL | V4L2_DEBUG_IOCTL_ARG;
-		#else
+#else
 			vdev->dev_debug = V4L2_DEV_DEBUG_IOCTL | V4L2_DEV_DEBUG_IOCTL_ARG;
-		#endif
+#endif
 
 	/* since kernel-3.7, there is a new field 'vfl_dir' that has to be
 	 * set to VFL_DIR_M2M for bidrectional devices */
@@ -2114,11 +2117,11 @@ static void init_vdev(struct video_device *vdev, int nr)
 static void init_capture_param(struct v4l2_captureparm *capture_param)
 {
 	MARK();
-	capture_param->capability               = 0;
-	capture_param->capturemode              = 0;
-	capture_param->extendedmode             = 0;
-	capture_param->readbuffers              = max_buffers;
-	capture_param->timeperframe.numerator   = 1;
+	capture_param->capability		= 0;
+	capture_param->capturemode		= 0;
+	capture_param->extendedmode		= 0;
+	capture_param->readbuffers		= max_buffers;
+	capture_param->timeperframe.numerator	= 1;
 	capture_param->timeperframe.denominator = 30;
 }
 
@@ -2177,10 +2180,10 @@ static int v4l2_loopback_init(struct v4l2_loopback_device *dev, int nr)
 	int ret;
 	struct v4l2_ctrl_handler *hdl = &dev->ctrl_handler;
 	snprintf(dev->v4l2_dev.name, sizeof(dev->v4l2_dev.name),
-                        "v4l2loopback-%03d", nr);
-        ret = v4l2_device_register(NULL, &dev->v4l2_dev);
-        if (ret)
-                return ret;
+			"v4l2loopback-%03d", nr);
+	ret = v4l2_device_register(NULL, &dev->v4l2_dev);
+	if (ret)
+		return ret;
 
 	MARK();
 	dev->vdev = video_device_alloc();
@@ -2230,7 +2233,7 @@ static int v4l2_loopback_init(struct v4l2_loopback_device *dev, int nr)
 	setup_timer(&dev->sustain_timer, sustain_timer_clb, nr);
 	setup_timer(&dev->timeout_timer, timeout_timer_clb, nr);
 #endif
-        dev->reread_count = 0;
+	dev->reread_count = 0;
 	dev->timeout_jiffies = 0;
 	dev->timeout_image = NULL;
 	dev->timeout_happened = 0;
@@ -2242,10 +2245,10 @@ static int v4l2_loopback_init(struct v4l2_loopback_device *dev, int nr)
 	v4l2_ctrl_new_custom(hdl, &v4l2loopback_ctrl_sustainframerate, NULL);
 	v4l2_ctrl_new_custom(hdl, &v4l2loopback_ctrl_timeout, NULL);
 	v4l2_ctrl_new_custom(hdl, &v4l2loopback_ctrl_timeoutimageio, NULL);
-        if (hdl->error) {
-                ret = hdl->error;
-                goto error;
-        }
+	if (hdl->error) {
+		ret = hdl->error;
+		goto error;
+	}
 	dev->v4l2_dev.ctrl_handler = hdl;
 
 	/* FIXME set buffers to 0 */
@@ -2267,55 +2270,55 @@ static int v4l2_loopback_init(struct v4l2_loopback_device *dev, int nr)
 	return 0;
 
 error:
-        v4l2_ctrl_handler_free(&dev->ctrl_handler);
-        v4l2_device_unregister(&dev->v4l2_dev);
+	v4l2_ctrl_handler_free(&dev->ctrl_handler);
+	v4l2_device_unregister(&dev->v4l2_dev);
 	kfree(dev->vdev);
-        return ret;
+	return ret;
 
 };
 
 /* LINUX KERNEL */
 static const struct v4l2_file_operations v4l2_loopback_fops = {
-	.owner   = THIS_MODULE,
-	.open    = v4l2_loopback_open,
+	.owner	 = THIS_MODULE,
+	.open	 = v4l2_loopback_open,
 	.release = v4l2_loopback_close,
-	.read    = v4l2_loopback_read,
-	.write   = v4l2_loopback_write,
-	.poll    = v4l2_loopback_poll,
-	.mmap    = v4l2_loopback_mmap,
-	.unlocked_ioctl   = video_ioctl2,
+	.read	 = v4l2_loopback_read,
+	.write	 = v4l2_loopback_write,
+	.poll	 = v4l2_loopback_poll,
+	.mmap	 = v4l2_loopback_mmap,
+	.unlocked_ioctl	  = video_ioctl2,
 };
 
 static const struct v4l2_ioctl_ops v4l2_loopback_ioctl_ops = {
-	.vidioc_querycap         = &vidioc_querycap,
+	.vidioc_querycap	 = &vidioc_querycap,
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)
-	.vidioc_enum_framesizes  = &vidioc_enum_framesizes,
+	.vidioc_enum_framesizes	 = &vidioc_enum_framesizes,
 	.vidioc_enum_frameintervals = &vidioc_enum_frameintervals,
 #endif
 
 #ifndef HAVE__V4L2_CTRLS
-	.vidioc_queryctrl         = &vidioc_queryctrl,
-	.vidioc_g_ctrl            = &vidioc_g_ctrl,
-	.vidioc_s_ctrl            = &vidioc_s_ctrl,
+	.vidioc_queryctrl	  = &vidioc_queryctrl,
+	.vidioc_g_ctrl		  = &vidioc_g_ctrl,
+	.vidioc_s_ctrl		  = &vidioc_s_ctrl,
 #endif /* HAVE__V4L2_CTRLS */
 
-	.vidioc_enum_output       = &vidioc_enum_output,
-	.vidioc_g_output          = &vidioc_g_output,
-	.vidioc_s_output          = &vidioc_s_output,
+	.vidioc_enum_output	  = &vidioc_enum_output,
+	.vidioc_g_output	  = &vidioc_g_output,
+	.vidioc_s_output	  = &vidioc_s_output,
 
-	.vidioc_enum_input       = &vidioc_enum_input,
-	.vidioc_g_input          = &vidioc_g_input,
-	.vidioc_s_input          = &vidioc_s_input,
+	.vidioc_enum_input	 = &vidioc_enum_input,
+	.vidioc_g_input		 = &vidioc_g_input,
+	.vidioc_s_input		 = &vidioc_s_input,
 
 	.vidioc_enum_fmt_vid_cap = &vidioc_enum_fmt_cap,
-	.vidioc_g_fmt_vid_cap    = &vidioc_g_fmt_cap,
-	.vidioc_s_fmt_vid_cap    = &vidioc_s_fmt_cap,
-	.vidioc_try_fmt_vid_cap  = &vidioc_try_fmt_cap,
+	.vidioc_g_fmt_vid_cap	 = &vidioc_g_fmt_cap,
+	.vidioc_s_fmt_vid_cap	 = &vidioc_s_fmt_cap,
+	.vidioc_try_fmt_vid_cap	 = &vidioc_try_fmt_cap,
 
 	.vidioc_enum_fmt_vid_out = &vidioc_enum_fmt_out,
-	.vidioc_s_fmt_vid_out    = &vidioc_s_fmt_out,
-	.vidioc_g_fmt_vid_out    = &vidioc_g_fmt_out,
-	.vidioc_try_fmt_vid_out  = &vidioc_try_fmt_out,
+	.vidioc_s_fmt_vid_out	 = &vidioc_s_fmt_out,
+	.vidioc_g_fmt_vid_out	 = &vidioc_g_fmt_out,
+	.vidioc_try_fmt_vid_out	 = &vidioc_try_fmt_out,
 
 #ifdef V4L2L_OVERLAY
 	.vidioc_s_fmt_vid_overlay = &vidioc_s_fmt_overlay,
@@ -2323,24 +2326,24 @@ static const struct v4l2_ioctl_ops v4l2_loopback_ioctl_ops = {
 #endif
 
 #ifdef V4L2LOOPBACK_WITH_STD
-	.vidioc_s_std            = &vidioc_s_std,
-	.vidioc_g_std            = &vidioc_g_std,
-	.vidioc_querystd         = &vidioc_querystd,
+	.vidioc_s_std		 = &vidioc_s_std,
+	.vidioc_g_std		 = &vidioc_g_std,
+	.vidioc_querystd	 = &vidioc_querystd,
 #endif /* V4L2LOOPBACK_WITH_STD */
 
-	.vidioc_g_parm           = &vidioc_g_parm,
-	.vidioc_s_parm           = &vidioc_s_parm,
+	.vidioc_g_parm		 = &vidioc_g_parm,
+	.vidioc_s_parm		 = &vidioc_s_parm,
 
-	.vidioc_reqbufs          = &vidioc_reqbufs,
-	.vidioc_querybuf         = &vidioc_querybuf,
-	.vidioc_qbuf             = &vidioc_qbuf,
-	.vidioc_dqbuf            = &vidioc_dqbuf,
+	.vidioc_reqbufs		 = &vidioc_reqbufs,
+	.vidioc_querybuf	 = &vidioc_querybuf,
+	.vidioc_qbuf		 = &vidioc_qbuf,
+	.vidioc_dqbuf		 = &vidioc_dqbuf,
 
-	.vidioc_streamon         = &vidioc_streamon,
-	.vidioc_streamoff        = &vidioc_streamoff,
+	.vidioc_streamon	 = &vidioc_streamon,
+	.vidioc_streamoff	 = &vidioc_streamoff,
 
 #ifdef CONFIG_VIDEO_V4L1_COMPAT
-	.vidiocgmbuf             = &vidiocgmbuf,
+	.vidiocgmbuf		 = &vidiocgmbuf,
 #endif
 };
 
@@ -2459,10 +2462,10 @@ static void v4l2loopback_cleanup_module(void)
 #ifdef MODULE
 int __init init_module(void)
 {
-        return v4l2loopback_init_module();
+	return v4l2loopback_init_module();
 }
 void __exit cleanup_module(void) {
-        return v4l2loopback_cleanup_module();
+	return v4l2loopback_cleanup_module();
 }
 #else
 late_initcall(v4l2loopback_init_module);