diff mbox

[1/1,v2] Add plugin support to libv4l

Message ID db37feca5fecc23b024751467cac65039bac4cd6.1295024151.git.ykamenov@mm-sol.com (mailing list archive)
State Not Applicable
Headers show

Commit Message

Yordan Kamenov Jan. 14, 2011, 5:18 p.m. UTC
None
diff mbox

Patch

diff --git a/lib/include/libv4l2-plugin.h b/lib/include/libv4l2-plugin.h
new file mode 100644
index 0000000..3971735
--- /dev/null
+++ b/lib/include/libv4l2-plugin.h
@@ -0,0 +1,43 @@ 
+/*
+* Copyright (C) 2010 Nokia Corporation <multimedia@maemo.org>
+
+* This program is free software; you can redistribute it and/or modify
+* it under the terms of the GNU Lesser General Public License as published by
+* the Free Software Foundation; either version 2.1 of the License, or
+* (at your option) any later version.
+*
+* 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
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser 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
+*/
+
+#ifndef __LIBV4L2_PLUGIN_H
+#define __LIBV4L2_PLUGIN_H
+
+#include <sys/types.h>
+
+/* Structure libv4l2_dev_ops holds the calls from libv4ls to video nodes.
+   They can be normal open/clode/ioctl etc. or any of them may be replaced
+   with a callback by a loaded plugin.
+*/
+
+struct libv4l2_dev_ops {
+	int (*open)(const char *file, int oflag,  mode_t mode);
+	int (*close)(int fd);
+	int (*ioctl)(int fd, unsigned long int request, void *arg);
+	ssize_t (*read)(int fd, void *buffer, size_t n);
+	void *(*mmap)(void *start, size_t length, int prot, int flags,
+			int fd, int64_t offset);
+	int (*munmap)(void *_start, size_t length);
+};
+
+/* Plugin utility functions */
+void libv4l2_set_plugindata(int fd, void *plugin_data);
+void *libv4l2_get_plugindata(int fd);
+
+#endif
diff --git a/lib/include/libv4l2.h b/lib/include/libv4l2.h
index cc0ab4a..5db000f 100644
--- a/lib/include/libv4l2.h
+++ b/lib/include/libv4l2.h
@@ -22,6 +22,7 @@ 
 #include <stdio.h>
 #include <unistd.h>
 #include <stdint.h>
+#include "libv4l2-plugin.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -106,7 +107,8 @@  LIBV4L_PUBLIC int v4l2_get_control(int fd, int cid);
 
    Returns fd on success, -1 if the fd is not suitable for use through libv4l2
    (note the fd is left open in this case). */
-LIBV4L_PUBLIC int v4l2_fd_open(int fd, int v4l2_flags);
+LIBV4L_PUBLIC int v4l2_fd_open(int fd, struct libv4l2_dev_ops *dev_ops,
+		int v4l2_flags);
 
 #ifdef __cplusplus
 }
diff --git a/lib/include/libv4lconvert.h b/lib/include/libv4lconvert.h
index 0264290..f210b2d 100644
--- a/lib/include/libv4lconvert.h
+++ b/lib/include/libv4lconvert.h
@@ -38,6 +38,8 @@ 
 
 #include <linux/videodev2.h>
 
+#include "libv4l2-plugin.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif /* __cplusplus */
@@ -50,7 +52,8 @@  extern "C" {
 
 struct v4lconvert_data;
 
-LIBV4L_PUBLIC struct v4lconvert_data *v4lconvert_create(int fd);
+LIBV4L_PUBLIC struct v4lconvert_data *v4lconvert_create(int fd,
+		struct libv4l2_dev_ops *dev_ops);
 LIBV4L_PUBLIC void v4lconvert_destroy(struct v4lconvert_data *data);
 
 /* When doing flipping / rotating / video-processing, only supported
diff --git a/lib/libv4l1/libv4l1.c b/lib/libv4l1/libv4l1.c
index fee0fb7..180db0e 100644
--- a/lib/libv4l1/libv4l1.c
+++ b/lib/libv4l1/libv4l1.c
@@ -342,7 +342,7 @@  int v4l1_open(const char *file, int oflag, ...)
 
 	/* Register with libv4l2, as we use that todo format conversion and read()
 	   emulation for us */
-	if (v4l2_fd_open(fd, 0) == -1) {
+	if (v4l2_fd_open(fd, NULL, 0) == -1) {
 		int saved_err = errno;
 
 		SYS_CLOSE(fd);
diff --git a/lib/libv4l2/Makefile b/lib/libv4l2/Makefile
index d78632f..eb1c019 100644
--- a/lib/libv4l2/Makefile
+++ b/lib/libv4l2/Makefile
@@ -1,8 +1,8 @@ 
 override CPPFLAGS += -I../include -fvisibility=hidden
 
-LIBS_libv4l2  = -lpthread
+LIBS_libv4l2  = -lpthread -ldl
 
-V4L2_OBJS     = libv4l2.o log.o
+V4L2_OBJS     = libv4l2.o v4l2-plugin.o log.o
 V4L2CONVERT   = v4l2convert.so
 V4L2CONVERT_O = v4l2convert.o libv4l2.so
 TARGETS       = $(V4L2_LIB) libv4l2.pc
diff --git a/lib/libv4l2/libv4l2-priv.h b/lib/libv4l2/libv4l2-priv.h
index 46d6103..ac4ccd6 100644
--- a/lib/libv4l2/libv4l2-priv.h
+++ b/lib/libv4l2/libv4l2-priv.h
@@ -85,8 +85,32 @@  struct v4l2_dev_info {
 	/* buffer when doing conversion and using read() for read() */
 	int readbuf_size;
 	unsigned char *readbuf;
+	struct libv4l2_dev_ops dev_ops;
+	/* plugin info */
+	void *plugin_library;
+	void *plugin_data;
 };
 
+int dev_open(const char *file, int oflag, mode_t mode);
+int dev_close(int fd);
+int dev_ioctl(int fd, unsigned long cmd, void *arg);
+ssize_t dev_read(int fd, void *buf, size_t len);
+void *dev_mmap(void *addr, size_t len, int prot, int flags, int fd, int64_t off);
+int dev_munmap(void *addr, size_t len);
+
+
+LIBV4L_PUBLIC int v4l2_plugin_open(int *plugin_used, const char *file,
+					int oflag, ...);
+LIBV4L_PUBLIC void *v4l2_plugin_mmap(int *plugin_used, void *start,
+					size_t length, int prot, int flags,
+					int fd, int64_t offset);
+LIBV4L_PUBLIC int v4l2_plugin_munmap(int *plugin_used, void *_start,
+					size_t length);
+
+extern struct v4l2_dev_info devices[V4L2_MAX_DEVICES];
+extern pthread_mutex_t v4l2_open_mutex;
+extern int devices_used;
+
 /* From log.c */
 void v4l2_log_ioctl(unsigned long int request, void *arg, int result);
 
diff --git a/lib/libv4l2/libv4l2.c b/lib/libv4l2/libv4l2.c
index ab85ea7..e066870 100644
--- a/lib/libv4l2/libv4l2.c
+++ b/lib/libv4l2/libv4l2.c
@@ -67,6 +67,7 @@ 
 #include <sys/stat.h>
 #include "libv4l2.h"
 #include "libv4l2-priv.h"
+#include "libv4l2-plugin.h"
 
 /* Note these flags are stored together with the flags passed to v4l2_fd_open()
    in v4l2_dev_info's flags member, so care should be taken that the do not
@@ -81,14 +82,23 @@ 
 
 #define V4L2_MMAP_OFFSET_MAGIC      0xABCDEF00u
 
-static pthread_mutex_t v4l2_open_mutex = PTHREAD_MUTEX_INITIALIZER;
-static struct v4l2_dev_info devices[V4L2_MAX_DEVICES] = {
+pthread_mutex_t v4l2_open_mutex = PTHREAD_MUTEX_INITIALIZER;
+struct v4l2_dev_info devices[V4L2_MAX_DEVICES] = {
 	{ .fd = -1 },
 	{ .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 },
 	{ .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 },
 	{ .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }
 };
-static int devices_used;
+int devices_used;
+
+struct libv4l2_dev_ops default_operations = {
+	.open = &dev_open,
+	.close = &dev_close,
+	.ioctl = &dev_ioctl,
+	.read = &dev_read,
+	.mmap = &dev_mmap,
+	.munmap = &dev_munmap
+};
 
 
 static int v4l2_request_read_buffers(int index)
@@ -102,7 +112,8 @@  static int v4l2_request_read_buffers(int index)
 		devices[index].nreadbuffers;
 	req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 	req.memory = V4L2_MEMORY_MMAP;
-	result = SYS_IOCTL(devices[index].fd, VIDIOC_REQBUFS, &req);
+	result = devices[index].dev_ops.ioctl(devices[index].fd,
+			VIDIOC_REQBUFS, &req);
 	if (result < 0) {
 		int saved_err = errno;
 
@@ -131,7 +142,7 @@  static void v4l2_unrequest_read_buffers(int index)
 	req.count = 0;
 	req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 	req.memory = V4L2_MEMORY_MMAP;
-	if (SYS_IOCTL(devices[index].fd, VIDIOC_REQBUFS, &req) < 0)
+	if (devices[index].dev_ops.ioctl(devices[index].fd, VIDIOC_REQBUFS, &req) < 0)
 		return;
 
 	devices[index].no_frames = MIN(req.count, V4L2_MAX_NO_FRAMES);
@@ -152,7 +163,8 @@  static int v4l2_map_buffers(int index)
 		buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 		buf.memory = V4L2_MEMORY_MMAP;
 		buf.index = i;
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_QUERYBUF, &buf);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_QUERYBUF, &buf);
 		if (result) {
 			int saved_err = errno;
 
@@ -202,7 +214,8 @@  static int v4l2_streamon(int index)
 	enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 
 	if (!(devices[index].flags & V4L2_STREAMON)) {
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_STREAMON, &type);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_STREAMON, &type);
 		if (result) {
 			int saved_err = errno;
 
@@ -223,7 +236,8 @@  static int v4l2_streamoff(int index)
 	enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 
 	if (devices[index].flags & V4L2_STREAMON) {
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_STREAMOFF, &type);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_STREAMOFF, &type);
 		if (result) {
 			int saved_err = errno;
 
@@ -252,7 +266,8 @@  static int v4l2_queue_read_buffer(int index, int buffer_index)
 	buf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 	buf.memory = V4L2_MEMORY_MMAP;
 	buf.index  = buffer_index;
-	result = SYS_IOCTL(devices[index].fd, VIDIOC_QBUF, &buf);
+	result = devices[index].dev_ops.ioctl(devices[index].fd,
+			VIDIOC_QBUF, &buf);
 	if (result) {
 		int saved_err = errno;
 
@@ -277,7 +292,8 @@  static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
 		return result;
 
 	do {
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_DQBUF, buf);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_DQBUF, buf);
 		if (result) {
 			if (errno != EAGAIN) {
 				int saved_err = errno;
@@ -356,7 +372,8 @@  static int v4l2_read_and_convert(int index, unsigned char *dest, int dest_size)
 	}
 
 	do {
-		result = SYS_READ(devices[index].fd, devices[index].readbuf, buf_size);
+		result = devices[index].dev_ops.read(devices[index].fd,
+				devices[index].readbuf, buf_size);
 		if (result <= 0) {
 			if (result && errno != EAGAIN) {
 				int saved_err = errno;
@@ -496,7 +513,7 @@  static int v4l2_buffers_mapped(int index)
 			buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 			buf.memory = V4L2_MEMORY_MMAP;
 			buf.index = i;
-			if (SYS_IOCTL(devices[index].fd, VIDIOC_QUERYBUF, &buf)) {
+			if (devices[index].dev_ops.ioctl(devices[index].fd, VIDIOC_QUERYBUF, &buf)) {
 				int saved_err = errno;
 
 				V4L2_LOG_ERR("querying buffer %u: %s\n", i, strerror(errno));
@@ -522,7 +539,24 @@  static int v4l2_buffers_mapped(int index)
 
 int v4l2_open(const char *file, int oflag, ...)
 {
-	int fd;
+	int fd, plugin_used;
+
+	if (oflag & O_CREAT) {
+		va_list ap;
+		mode_t mode;
+
+		va_start(ap, oflag);
+		mode = va_arg(ap, mode_t);
+
+		fd = v4l2_plugin_open(&plugin_used, file, oflag, mode);
+
+		va_end(ap);
+	} else {
+		fd = v4l2_plugin_open(&plugin_used, file, oflag, 0);
+	}
+
+	if (plugin_used)
+		return fd;
 
 	/* original open code */
 	if (oflag & O_CREAT) {
@@ -543,7 +577,7 @@  int v4l2_open(const char *file, int oflag, ...)
 	if (fd == -1)
 		return fd;
 
-	if (v4l2_fd_open(fd, 0) == -1) {
+	if (v4l2_fd_open(fd, NULL, 0) == -1) {
 		int saved_err = errno;
 
 		SYS_CLOSE(fd);
@@ -554,7 +588,8 @@  int v4l2_open(const char *file, int oflag, ...)
 	return fd;
 }
 
-int v4l2_fd_open(int fd, int v4l2_flags)
+int v4l2_fd_open(int fd, struct libv4l2_dev_ops *dev_ops,
+		int v4l2_flags)
 {
 	int i, index;
 	char *lfname;
@@ -562,6 +597,9 @@  int v4l2_fd_open(int fd, int v4l2_flags)
 	struct v4l2_format fmt;
 	struct v4lconvert_data *convert;
 
+	if (dev_ops == NULL)
+		dev_ops = &default_operations;
+
 	/* If no log file was set by the app, see if one was specified through the
 	   environment */
 	if (!v4l2_log_file) {
@@ -571,7 +609,7 @@  int v4l2_fd_open(int fd, int v4l2_flags)
 	}
 
 	/* check that this is an v4l2 device */
-	if (SYS_IOCTL(fd, VIDIOC_QUERYCAP, &cap)) {
+	if (dev_ops->ioctl(fd, VIDIOC_QUERYCAP, &cap)) {
 		int saved_err = errno;
 
 		V4L2_LOG_ERR("getting capabilities: %s\n", strerror(errno));
@@ -586,7 +624,7 @@  int v4l2_fd_open(int fd, int v4l2_flags)
 
 	/* Get current cam format */
 	fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-	if (SYS_IOCTL(fd, VIDIOC_G_FMT, &fmt)) {
+	if (dev_ops->ioctl(fd, VIDIOC_G_FMT, &fmt)) {
 		int saved_err = errno;
 
 		V4L2_LOG_ERR("getting pixformat: %s\n", strerror(errno));
@@ -595,15 +633,22 @@  int v4l2_fd_open(int fd, int v4l2_flags)
 	}
 
 	/* init libv4lconvert */
-	convert = v4lconvert_create(fd);
+	convert = v4lconvert_create(fd, dev_ops);
 	if (!convert)
 		return -1;
 
 	/* So we have a v4l2 capture device, register it in our devices array */
 	pthread_mutex_lock(&v4l2_open_mutex);
 	for (index = 0; index < V4L2_MAX_DEVICES; index++)
-		if (devices[index].fd == -1) {
+		if (devices[index].fd == fd || devices[index].fd == -1) {
 			devices[index].fd = fd;
+
+			devices[index].dev_ops.open = dev_ops->open;
+			devices[index].dev_ops.close = dev_ops->close;
+			devices[index].dev_ops.ioctl = dev_ops->ioctl;
+			devices[index].dev_ops.read = dev_ops->read;
+			devices[index].dev_ops.mmap = dev_ops->mmap;
+			devices[index].dev_ops.munmap = dev_ops->munmap;
 			break;
 		}
 	pthread_mutex_unlock(&v4l2_open_mutex);
@@ -723,7 +768,7 @@  int v4l2_close(int fd)
 	/* Since we've marked the fd as no longer used, and freed the resources,
 	   redo the close in case it was interrupted */
 	do {
-		result = SYS_CLOSE(fd);
+		result = devices[index].dev_ops.close(fd);
 	} while (result == -1 && errno == EINTR);
 
 	V4L2_LOG("close: %d\n", fd);
@@ -879,7 +924,7 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 	}
 
 	if (!is_capture_request) {
-		result = SYS_IOCTL(fd, request, arg);
+		result = devices[index].dev_ops.ioctl(fd, request, arg);
 		saved_err = errno;
 		v4l2_log_ioctl(request, arg, result);
 		errno = saved_err;
@@ -927,7 +972,8 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 	case VIDIOC_QUERYCAP: {
 		struct v4l2_capability *cap = arg;
 
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_QUERYCAP, cap);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_QUERYCAP, cap);
 		if (result == 0)
 			/* We always support read() as we fake it using mmap mode */
 			cap->capabilities |= V4L2_CAP_READWRITE;
@@ -977,8 +1023,8 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 		}
 
 		if (devices[index].flags & V4L2_DISABLE_CONVERSION) {
-			result = SYS_IOCTL(devices[index].fd, VIDIOC_TRY_FMT,
-					dest_fmt);
+			result = devices[index].dev_ops.ioctl(devices[index].fd,
+					VIDIOC_TRY_FMT, dest_fmt);
 			src_fmt = *dest_fmt;
 		} else {
 			result = v4lconvert_try_format(devices[index].convert, dest_fmt,
@@ -1018,7 +1064,8 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 			break;
 
 		req_pix_fmt = src_fmt.fmt.pix;
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_S_FMT, &src_fmt);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_S_FMT, &src_fmt);
 		if (result) {
 			saved_err = errno;
 			V4L2_LOG_ERR("setting pixformat: %s\n", strerror(errno));
@@ -1067,7 +1114,8 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 		if (req->count > V4L2_MAX_NO_FRAMES)
 			req->count = V4L2_MAX_NO_FRAMES;
 
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_REQBUFS, req);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_REQBUFS, req);
 		if (result < 0)
 			break;
 		result = 0; /* some drivers return the number of buffers on success */
@@ -1088,7 +1136,8 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 
 		/* Do a real query even when converting to let the driver fill in
 		   things like buf->field */
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_QUERYBUF, buf);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_QUERYBUF, buf);
 		if (result || !v4l2_needs_conversion(index))
 			break;
 
@@ -1115,7 +1164,8 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 				break;
 		}
 
-		result = SYS_IOCTL(devices[index].fd, VIDIOC_QBUF, arg);
+		result = devices[index].dev_ops.ioctl(devices[index].fd,
+				VIDIOC_QBUF, arg);
 		break;
 
 	case VIDIOC_DQBUF: {
@@ -1128,7 +1178,8 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 		}
 
 		if (!v4l2_needs_conversion(index)) {
-			result = SYS_IOCTL(devices[index].fd, VIDIOC_DQBUF, buf);
+			result = devices[index].dev_ops.ioctl(devices[index].fd,
+					VIDIOC_DQBUF, buf);
 			if (result) {
 				int saved_err = errno;
 
@@ -1187,7 +1238,7 @@  int v4l2_ioctl(int fd, unsigned long int request, ...)
 		break;
 
 	default:
-		result = SYS_IOCTL(fd, request, arg);
+		result = devices[index].dev_ops.ioctl(fd, request, arg);
 		break;
 	}
 
@@ -1217,7 +1268,7 @@  ssize_t v4l2_read(int fd, void *dest, size_t n)
 	   it */
 	if ((devices[index].flags & V4L2_SUPPORTS_READ) &&
 			!v4l2_needs_conversion(index)) {
-		result = SYS_READ(fd, dest, n);
+		result = devices[index].dev_ops.read(fd, dest, n);
 		goto leave;
 	}
 
@@ -1264,10 +1315,16 @@  leave:
 void *v4l2_mmap(void *start, size_t length, int prot, int flags, int fd,
 		int64_t offset)
 {
-	int index;
+	int index, plugin_used;
 	unsigned int buffer_index;
 	void *result;
 
+	result = v4l2_plugin_mmap(&plugin_used, start, length, prot,
+							flags, fd, offset);
+
+	if (plugin_used)
+		return result;
+
 	index = v4l2_get_index(fd);
 	if (index == -1 ||
 			/* Check if the mmap data matches our answer to QUERY_BUF, if it doesn't
@@ -1329,10 +1386,15 @@  leave:
 
 int v4l2_munmap(void *_start, size_t length)
 {
-	int index;
+	int index, result, plugin_used;
 	unsigned int buffer_index;
 	unsigned char *start = _start;
 
+	result = v4l2_plugin_munmap(&plugin_used, _start, length);
+
+	if (plugin_used)
+		return result;
+
 	/* Is this memory ours? */
 	if (start != MAP_FAILED && length == V4L2_FRAME_BUF_SIZE) {
 		for (index = 0; index < devices_used; index++)
diff --git a/lib/libv4l2/v4l2-plugin.c b/lib/libv4l2/v4l2-plugin.c
new file mode 100644
index 0000000..22ea315
--- /dev/null
+++ b/lib/libv4l2/v4l2-plugin.c
@@ -0,0 +1,344 @@ 
+/*
+* Copyright (C) 2010 Nokia Corporation <multimedia@maemo.org>
+
+* This program is free software; you can redistribute it and/or modify
+* it under the terms of the GNU Lesser General Public License as published by
+* the Free Software Foundation; either version 2.1 of the License, or
+* (at your option) any later version.
+*
+* 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
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser 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 <stdarg.h>
+#include <dlfcn.h>
+#include <fcntl.h>
+#include <glob.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include "libv4l2.h"
+#include "libv4l2-priv.h"
+#include "libv4l2-plugin.h"
+
+/* libv4l plugin support:
+   it is provided by functions v4l2_plugin_[open,close,etc].
+
+   When open() is called libv4l dlopens files in /usr/lib[64]/libv4l/plugins
+   1 at a time and call open callback passing through the applications
+   parameters unmodified.
+
+   If a plugin is relevant for the specified device node, it can indicate so
+   by returning a value other then -1 (the actual file descriptor).
+   As soon as a plugin returns another value then -1 plugin loading stops and
+   information about it (fd and corresponding library handle) is stored. For
+   each function v4l2_[ioctl,read,close,etc] is called corresponding
+   v4l2_plugin_* function which looks if there is loaded plugin for that file
+   and call it's callbacks.
+
+   v4l2_plugin_* function indicates by it's first argument if plugin was used,
+   and if it was not then v4l2_* functions proceed with their usual behavior.
+*/
+
+#define PLUGINS_PATTERN "/usr/lib/libv4l/plugins/*.so"
+
+int dev_open(const char *file, int oflag, mode_t mode)
+{
+	return syscall(SYS_open, (const char *)(file), (int)(oflag),
+			(mode_t)(mode));
+}
+
+int dev_close(int fd)
+{
+	return syscall(SYS_close, (int)(fd));
+}
+
+int dev_ioctl(int fd, unsigned long cmd, void *arg)
+{
+	return syscall(SYS_ioctl, (int)(fd), (unsigned long)(cmd),
+			(void *)(arg));
+}
+
+ssize_t dev_read(int fd, void *buf, size_t len)
+{
+	return syscall(SYS_read, (int)(fd), (void *)(buf), (size_t)(len));
+}
+
+void *dev_mmap(void *addr, size_t len, int prot, int flags, int fd,
+		int64_t off)
+{
+	return (void *)syscall(SYS_mmap2, (void *)(addr), (size_t)(len),
+			(int)(prot), (int)(flags), (int)(fd),
+			(__off_t)((off) >> MMAP2_PAGE_SHIFT));
+}
+
+int dev_munmap(void *addr, size_t len)
+{
+	return syscall(SYS_munmap, (void *)(addr), (size_t)(len));
+}
+
+int v4l2_plugin_open(int *plugin_used, const char *file, int oflag, ...)
+{
+	char *error;
+	int index, fd = -1, glob_ret, plugin_num;
+	void *plugin_library = NULL;
+	struct libv4l2_dev_ops *libv4l2_plugin = NULL;
+	glob_t globbuf;
+
+	pthread_mutex_lock(&v4l2_open_mutex);
+	/* Check if there is empty slot for plugin */
+	for (index = 0; index < V4L2_MAX_DEVICES; index++)
+		if (devices[index].fd == -1)
+			break;
+	pthread_mutex_unlock(&v4l2_open_mutex);
+
+	if (index == V4L2_MAX_DEVICES) {
+		V4L2_LOG_ERR("attempting to open more than %d libv4l plugins\n",
+			V4L2_MAX_DEVICES);
+		*plugin_used = 0;
+		return -1;
+	}
+
+	glob_ret = glob(PLUGINS_PATTERN, 0, NULL, &globbuf);
+
+	if (glob_ret == GLOB_NOSPACE) {
+		*plugin_used = 0;
+		return -1;
+	}
+
+	if (glob_ret == GLOB_ABORTED || glob_ret == GLOB_NOMATCH) {
+		*plugin_used = 0;
+		goto leave;
+	}
+
+	for (plugin_num = 0; plugin_num < globbuf.gl_pathc; plugin_num++) {
+
+		V4L2_LOG("PLUGIN: dlopen(%s);\n", globbuf.gl_pathv[plugin_num]);
+
+		plugin_library = dlopen(globbuf.gl_pathv[plugin_num],
+							RTLD_LAZY);
+
+		if (!plugin_library)
+			continue;
+
+		dlerror();    /* Clear any existing error */
+		libv4l2_plugin = (struct libv4l2_dev_ops *)
+					dlsym(plugin_library, "libv4l2_plugin");
+
+		error = dlerror();
+		if (error != NULL)  {
+			V4L2_LOG_ERR("PLUGIN: dlsym failed: %s\n", error);
+			dlclose(plugin_library);
+
+			continue;
+		}
+
+		if (libv4l2_plugin->open == NULL) {
+			fd = -1;
+		} else {
+			if (oflag & O_CREAT) {
+				va_list ap;
+				mode_t mode;
+
+				va_start(ap, oflag);
+				mode = va_arg(ap, mode_t);
+
+				fd = libv4l2_plugin->open(file, oflag, mode);
+
+				va_end(ap);
+			} else {
+				fd = libv4l2_plugin->open(file, oflag, 0);
+			}
+		}
+
+		if (fd != -1) {
+			V4L2_LOG("PLUGIN: plugin open() returned %d\n", fd);
+
+			if (libv4l2_plugin->open == NULL)
+				libv4l2_plugin->open = &dev_open;
+			if (libv4l2_plugin->close == NULL)
+				libv4l2_plugin->close = &dev_close;
+			if (libv4l2_plugin->ioctl == NULL)
+				libv4l2_plugin->ioctl = &dev_ioctl;
+			if (libv4l2_plugin->read == NULL)
+				libv4l2_plugin->read = &dev_read;
+			if (libv4l2_plugin->mmap == NULL)
+				libv4l2_plugin->mmap = &dev_mmap;
+			if (libv4l2_plugin->munmap == NULL)
+				libv4l2_plugin->munmap = &dev_munmap;
+
+			v4l2_fd_open(fd, libv4l2_plugin, 0);
+
+			for (index = 0; index < V4L2_MAX_DEVICES; index++)
+				if (devices[index].fd == fd)
+					break;
+
+			/* The fd was not stored in devices[] array */
+			if (index == V4L2_MAX_DEVICES) {
+				libv4l2_plugin->close(fd);
+				dlclose(plugin_library);
+				fd = -1;
+				goto leave;
+			}
+
+			pthread_mutex_lock(&v4l2_open_mutex);
+			devices[index].plugin_library = plugin_library;
+			pthread_mutex_unlock(&v4l2_open_mutex);
+
+			break;
+		} else {
+			V4L2_LOG("PLUGIN: plugin open() returned -1\n");
+			dlclose(plugin_library);
+			plugin_library = NULL;
+		}
+
+	}
+
+leave:
+	globfree(&globbuf);
+
+	if (fd == -1)
+		*plugin_used = 0;
+	else
+		*plugin_used = 1;
+
+	return fd;
+}
+
+void *v4l2_plugin_mmap(int *plugin_used, void *start, size_t length, int prot,
+					int flags, int fd, int64_t offset)
+{
+	int index, i;
+	void *result = NULL;
+	void *plugin_library = NULL;
+	struct libv4l2_dev_ops *libv4l2_plugin = NULL;
+
+	pthread_mutex_lock(&v4l2_open_mutex);
+	for (index = 0; index < V4L2_MAX_DEVICES; index++)
+		if (devices[index].fd == fd) {
+			plugin_library = devices[index].plugin_library;
+			libv4l2_plugin = &(devices[index].dev_ops);
+			break;
+		}
+
+	if (fd == -1 || index == V4L2_MAX_DEVICES ||
+				libv4l2_plugin == NULL ||
+				libv4l2_plugin->mmap == NULL) {
+		*plugin_used = 0;
+	} else {
+		for (i = 0; i < V4L2_MAX_NO_FRAMES; i++)
+			if (devices[index].frame_pointers[i] == MAP_FAILED)
+				break;
+
+		if (i == V4L2_MAX_NO_FRAMES) {
+			*plugin_used = 0;
+			result = NULL;
+			goto leave;
+		}
+
+		result = libv4l2_plugin->mmap(start, length, prot,
+						flags, fd, offset);
+		if (result) {
+			devices[index].frame_pointers[i] = result;
+			devices[index].frame_sizes[i] = length;
+			*plugin_used = 1;
+		} else {
+			*plugin_used = 0;
+		}
+	}
+
+leave:
+	pthread_mutex_unlock(&v4l2_open_mutex);
+
+	return result;
+}
+
+int v4l2_plugin_munmap(int *plugin_used, void *_start, size_t length)
+{
+	int index, map, result = 0;
+	void *plugin_library = NULL;
+	struct libv4l2_dev_ops *libv4l2_plugin = NULL;
+
+	pthread_mutex_lock(&v4l2_open_mutex);
+	for (index = 0; index < V4L2_MAX_DEVICES; index++) {
+		for (map = 0; map < V4L2_MAX_NO_FRAMES; map++) {
+			if (devices[index].frame_pointers[map] == _start &&
+				devices[index].frame_sizes[map] == length) {
+
+				plugin_library = devices[index].plugin_library;
+				libv4l2_plugin = &(devices[index].dev_ops);
+				devices[index].frame_pointers[map] = MAP_FAILED;
+				devices[index].frame_sizes[map] = 0;
+				break;
+			}
+		}
+		if (plugin_library)
+			break;
+	}
+
+	if (plugin_library) {
+		result = libv4l2_plugin->munmap(_start, length);
+
+		if (result)
+			*plugin_used = 0;
+		else
+			*plugin_used = 1;
+
+	} else {
+		*plugin_used = 0;
+	}
+
+	pthread_mutex_unlock(&v4l2_open_mutex);
+
+	return result;
+}
+
+LIBV4L_PUBLIC void libv4l2_set_plugindata(int fd, void *plugin_data)
+{
+	int index;
+
+	pthread_mutex_lock(&v4l2_open_mutex);
+	for (index = 0; index < V4L2_MAX_DEVICES; index++)
+		if (devices[index].fd == fd)
+			break;
+
+	/* We have no info about this fd - reserve an empty slot */
+	if (index == V4L2_MAX_DEVICES) {
+		for (index = 0; index < V4L2_MAX_DEVICES; index++)
+			if (devices[index].fd == -1)
+				break;
+	}
+	pthread_mutex_unlock(&v4l2_open_mutex);
+
+	if (index == V4L2_MAX_DEVICES) {
+		V4L2_LOG_ERR("store private data for more than %d plugins\n",
+			V4L2_MAX_DEVICES);
+		return;
+	}
+
+	pthread_mutex_lock(&v4l2_open_mutex);
+	devices[index].fd = fd;
+	devices[index].plugin_data = plugin_data;
+	pthread_mutex_unlock(&v4l2_open_mutex);
+}
+
+LIBV4L_PUBLIC void *libv4l2_get_plugindata(int fd)
+{
+	int index;
+	void *result = NULL;
+
+	pthread_mutex_lock(&v4l2_open_mutex);
+	for (index = 0; index < V4L2_MAX_DEVICES; index++)
+		if (devices[index].fd == fd) {
+			result = devices[index].plugin_data;
+			break;
+		}
+	pthread_mutex_unlock(&v4l2_open_mutex);
+
+	return result;
+}
diff --git a/lib/libv4l2/v4l2convert.c b/lib/libv4l2/v4l2convert.c
index e251085..820c8ae 100644
--- a/lib/libv4l2/v4l2convert.c
+++ b/lib/libv4l2/v4l2convert.c
@@ -31,6 +31,8 @@ 
 #include "../libv4lconvert/libv4lsyscall-priv.h"
 #include <linux/videodev2.h>
 #include <libv4l2.h>
+#include "libv4l2-plugin.h"
+#include "libv4l2-priv.h"
 
 /* Check that open/read/mmap is not a define */
 #if defined open || defined read || defined mmap
@@ -45,10 +47,27 @@ 
 
 LIBV4L_PUBLIC int open(const char *file, int oflag, ...)
 {
-	int fd;
+	int fd, plugin_used;
 	struct v4l2_capability cap;
 	int v4l_device = 0;
 
+	if (oflag & O_CREAT) {
+		va_list ap;
+		mode_t mode;
+
+		va_start(ap, oflag);
+		mode = va_arg(ap, mode_t);
+
+		fd = v4l2_plugin_open(&plugin_used, file, oflag, mode);
+
+		va_end(ap);
+	} else {
+		fd = v4l2_plugin_open(&plugin_used, file, oflag, 0);
+	}
+
+	if (plugin_used)
+		return fd;
+
 	/* check if we're opening a video4linux2 device */
 	if (!strncmp(file, "/dev/video", 10) || !strncmp(file, "/dev/v4l/", 9)) {
 		/* Some apps open the device read only, but we need rw rights as the
@@ -86,7 +105,7 @@  LIBV4L_PUBLIC int open(const char *file, int oflag, ...)
 
 	/* Try to Register with libv4l2 (in case of failure pass the fd to the
 	   application as is) */
-	v4l2_fd_open(fd, 0);
+	v4l2_fd_open(fd, NULL, 0);
 
 	return fd;
 }
diff --git a/lib/libv4lconvert/control/libv4lcontrol-priv.h b/lib/libv4lconvert/control/libv4lcontrol-priv.h
index 22cdf34..3a392e4 100644
--- a/lib/libv4lconvert/control/libv4lcontrol-priv.h
+++ b/lib/libv4lconvert/control/libv4lcontrol-priv.h
@@ -22,6 +22,8 @@ 
 #ifndef __LIBV4LCONTROL_PRIV_H
 #define __LIBV4LCONTROL_PRIV_H
 
+#include "libv4l2-plugin.h"
+
 #define V4LCONTROL_SHM_SIZE 4096
 
 #define V4LCONTROL_SUPPORTS_NEXT_CTRL 0x01
@@ -37,6 +39,7 @@  struct v4lcontrol_data {
 	unsigned int *shm_values; /* shared memory control value store */
 	unsigned int old_values[V4LCONTROL_COUNT]; /* for controls_changed() */
 	const struct v4lcontrol_flags_info *flags_info;
+	struct libv4l2_dev_ops *dev_ops;
 };
 
 struct v4lcontrol_flags_info {
diff --git a/lib/libv4lconvert/control/libv4lcontrol.c b/lib/libv4lconvert/control/libv4lcontrol.c
index d91d8e6..6e12e59 100644
--- a/lib/libv4lconvert/control/libv4lcontrol.c
+++ b/lib/libv4lconvert/control/libv4lcontrol.c
@@ -679,7 +679,8 @@  static void v4lcontrol_get_flags_from_db(struct v4lcontrol_data *data,
 		}
 }
 
-struct v4lcontrol_data *v4lcontrol_create(int fd, int always_needs_conversion)
+struct v4lcontrol_data *v4lcontrol_create(int fd,
+		struct libv4l2_dev_ops *dev_ops, int always_needs_conversion)
 {
 	int shm_fd;
 	int i, rc, got_usb_ids, init = 0;
@@ -699,10 +700,11 @@  struct v4lcontrol_data *v4lcontrol_create(int fd, int always_needs_conversion)
 	}
 
 	data->fd = fd;
+	data->dev_ops = dev_ops;
 
 	/* Check if the driver has indicated some form of flipping is needed */
-	if ((SYS_IOCTL(data->fd, VIDIOC_G_INPUT, &input.index) == 0) &&
-			(SYS_IOCTL(data->fd, VIDIOC_ENUMINPUT, &input) == 0)) {
+	if ((data->dev_ops->ioctl(data->fd, VIDIOC_G_INPUT, &input.index) == 0) &&
+			(data->dev_ops->ioctl(data->fd, VIDIOC_ENUMINPUT, &input) == 0)) {
 		if (input.status & V4L2_IN_ST_HFLIP)
 			data->flags |= V4LCONTROL_HFLIPPED;
 		if (input.status & V4L2_IN_ST_VFLIP)
@@ -719,7 +721,7 @@  struct v4lcontrol_data *v4lcontrol_create(int fd, int always_needs_conversion)
 		data->flags = strtol(s, NULL, 0);
 
 	ctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL;
-	if (SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, &ctrl) == 0)
+	if (data->dev_ops->ioctl(data->fd, VIDIOC_QUERYCTRL, &ctrl) == 0)
 		data->priv_flags |= V4LCONTROL_SUPPORTS_NEXT_CTRL;
 
 	/* If the device always needs conversion, we can add fake controls at no cost
@@ -727,7 +729,7 @@  struct v4lcontrol_data *v4lcontrol_create(int fd, int always_needs_conversion)
 	if (always_needs_conversion || v4lcontrol_needs_conversion(data)) {
 		for (i = 0; i < V4LCONTROL_AUTO_ENABLE_COUNT; i++) {
 			ctrl.id = fake_controls[i].id;
-			rc = SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, &ctrl);
+			rc = data->dev_ops->ioctl(data->fd, VIDIOC_QUERYCTRL, &ctrl);
 			if (rc == -1 || (rc == 0 && (ctrl.flags & V4L2_CTRL_FLAG_DISABLED)))
 				data->controls |= 1 << i;
 		}
@@ -739,17 +741,17 @@  struct v4lcontrol_data *v4lcontrol_create(int fd, int always_needs_conversion)
 	   different sensors with / without autogain or the necessary controls. */
 	while (data->flags & V4LCONTROL_WANTS_AUTOGAIN) {
 		ctrl.id = V4L2_CID_AUTOGAIN;
-		rc = SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, &ctrl);
+		rc = data->dev_ops->ioctl(data->fd, VIDIOC_QUERYCTRL, &ctrl);
 		if (rc == 0 && !(ctrl.flags & V4L2_CTRL_FLAG_DISABLED))
 			break;
 
 		ctrl.id = V4L2_CID_EXPOSURE;
-		rc = SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, &ctrl);
+		rc = data->dev_ops->ioctl(data->fd, VIDIOC_QUERYCTRL, &ctrl);
 		if (rc != 0 || (ctrl.flags & V4L2_CTRL_FLAG_DISABLED))
 			break;
 
 		ctrl.id = V4L2_CID_GAIN;
-		rc = SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, &ctrl);
+		rc = data->dev_ops->ioctl(data->fd, VIDIOC_QUERYCTRL, &ctrl);
 		if (rc != 0 || (ctrl.flags & V4L2_CTRL_FLAG_DISABLED))
 			break;
 
@@ -766,7 +768,7 @@  struct v4lcontrol_data *v4lcontrol_create(int fd, int always_needs_conversion)
 	if (data->controls == 0)
 		return data; /* No need to create a shared memory segment */
 
-	if (SYS_IOCTL(fd, VIDIOC_QUERYCAP, &cap)) {
+	if (data->dev_ops->ioctl(fd, VIDIOC_QUERYCAP, &cap)) {
 		perror("libv4lcontrol: error querying device capabilities");
 		goto error;
 	}
@@ -952,7 +954,7 @@  int v4lcontrol_vidioc_queryctrl(struct v4lcontrol_data *data, void *arg)
 		}
 
 	/* find out what the kernel driver would respond. */
-	retval = SYS_IOCTL(data->fd, VIDIOC_QUERYCTRL, arg);
+	retval = data->dev_ops->ioctl(data->fd, VIDIOC_QUERYCTRL, arg);
 
 	if ((data->priv_flags & V4LCONTROL_SUPPORTS_NEXT_CTRL) &&
 			(orig_id & V4L2_CTRL_FLAG_NEXT_CTRL)) {
@@ -989,7 +991,7 @@  int v4lcontrol_vidioc_g_ctrl(struct v4lcontrol_data *data, void *arg)
 			return 0;
 		}
 
-	return SYS_IOCTL(data->fd, VIDIOC_G_CTRL, arg);
+	return data->dev_ops->ioctl(data->fd, VIDIOC_G_CTRL, arg);
 }
 
 int v4lcontrol_vidioc_s_ctrl(struct v4lcontrol_data *data, void *arg)
@@ -1010,7 +1012,7 @@  int v4lcontrol_vidioc_s_ctrl(struct v4lcontrol_data *data, void *arg)
 			return 0;
 		}
 
-	return SYS_IOCTL(data->fd, VIDIOC_S_CTRL, arg);
+	return data->dev_ops->ioctl(data->fd, VIDIOC_S_CTRL, arg);
 }
 
 int v4lcontrol_get_flags(struct v4lcontrol_data *data)
diff --git a/lib/libv4lconvert/control/libv4lcontrol.h b/lib/libv4lconvert/control/libv4lcontrol.h
index 974e97a..770804a 100644
--- a/lib/libv4lconvert/control/libv4lcontrol.h
+++ b/lib/libv4lconvert/control/libv4lcontrol.h
@@ -22,6 +22,8 @@ 
 #ifndef __LIBV4LCONTROL_H
 #define __LIBV4LCONTROL_H
 
+#include "libv4l2-plugin.h"
+
 /* Flags */
 #define V4LCONTROL_HFLIPPED              0x01
 #define V4LCONTROL_VFLIPPED              0x02
@@ -47,7 +49,8 @@  enum {
 
 struct v4lcontrol_data;
 
-struct v4lcontrol_data *v4lcontrol_create(int fd, int always_needs_conversion);
+struct v4lcontrol_data *v4lcontrol_create(int fd,
+		struct libv4l2_dev_ops *dev_ops, int always_needs_conversion);
 void v4lcontrol_destroy(struct v4lcontrol_data *data);
 
 /* Functions used by v4lprocessing to get the control state */
diff --git a/lib/libv4lconvert/libv4lconvert-priv.h b/lib/libv4lconvert/libv4lconvert-priv.h
index d8fe899..0b1e3e7 100644
--- a/lib/libv4lconvert/libv4lconvert-priv.h
+++ b/lib/libv4lconvert/libv4lconvert-priv.h
@@ -65,6 +65,7 @@  struct v4lconvert_data {
 	unsigned char *convert_pixfmt_buf;
 	struct v4lcontrol_data *control;
 	struct v4lprocessing_data *processing;
+	struct libv4l2_dev_ops *dev_ops;
 
 	/* Data for external decompression helpers code */
 	pid_t decompress_pid;
diff --git a/lib/libv4lconvert/libv4lconvert.c b/lib/libv4lconvert/libv4lconvert.c
index 0d8b29f..c27401f 100644
--- a/lib/libv4lconvert/libv4lconvert.c
+++ b/lib/libv4lconvert/libv4lconvert.c
@@ -91,7 +91,8 @@  static const int v4lconvert_crop_res[][2] = {
 	{ 176, 144 },
 };
 
-struct v4lconvert_data *v4lconvert_create(int fd)
+struct v4lconvert_data *v4lconvert_create(int fd,
+		struct libv4l2_dev_ops *dev_ops)
 {
 	int i, j;
 	struct v4lconvert_data *data = calloc(1, sizeof(struct v4lconvert_data));
@@ -107,6 +108,7 @@  struct v4lconvert_data *v4lconvert_create(int fd)
 	}
 
 	data->fd = fd;
+	data->dev_ops = dev_ops;
 	data->decompress_pid = -1;
 
 	/* Check supported formats */
@@ -115,7 +117,7 @@  struct v4lconvert_data *v4lconvert_create(int fd)
 
 		fmt.index = i;
 
-		if (SYS_IOCTL(data->fd, VIDIOC_ENUM_FMT, &fmt))
+		if (data->dev_ops->ioctl(data->fd, VIDIOC_ENUM_FMT, &fmt))
 			break;
 
 		for (j = 0; j < ARRAY_SIZE(supported_src_pixfmts); j++)
@@ -134,7 +136,7 @@  struct v4lconvert_data *v4lconvert_create(int fd)
 	data->no_formats = i;
 
 	/* Check if this cam has any special flags */
-	if (SYS_IOCTL(data->fd, VIDIOC_QUERYCAP, &cap) == 0) {
+	if (data->dev_ops->ioctl(data->fd, VIDIOC_QUERYCAP, &cap) == 0) {
 		if (!strcmp((char *)cap.driver, "uvcvideo"))
 			data->flags |= V4LCONVERT_IS_UVC;
 
@@ -142,7 +144,7 @@  struct v4lconvert_data *v4lconvert_create(int fd)
 			always_needs_conversion = 0;
 	}
 
-	data->control = v4lcontrol_create(fd, always_needs_conversion);
+	data->control = v4lcontrol_create(fd, dev_ops, always_needs_conversion);
 	if (!data->control) {
 		free(data);
 		return NULL;
@@ -205,7 +207,7 @@  int v4lconvert_enum_fmt(struct v4lconvert_data *data, struct v4l2_fmtdesc *fmt)
 	if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
 			(!v4lconvert_supported_dst_fmt_only(data) &&
 			 fmt->index < data->no_formats))
-		return SYS_IOCTL(data->fd, VIDIOC_ENUM_FMT, fmt);
+		return data->dev_ops->ioctl(data->fd, VIDIOC_ENUM_FMT, fmt);
 
 	for (i = 0; i < ARRAY_SIZE(supported_dst_pixfmts); i++)
 		if (v4lconvert_supported_dst_fmt_only(data) ||
@@ -313,7 +315,7 @@  static int v4lconvert_do_try_format(struct v4lconvert_data *data,
 		try_fmt = *dest_fmt;
 		try_fmt.fmt.pix.pixelformat = supported_src_pixfmts[i].fmt;
 
-		if (!SYS_IOCTL(data->fd, VIDIOC_TRY_FMT, &try_fmt)) {
+		if (!data->dev_ops->ioctl(data->fd, VIDIOC_TRY_FMT, &try_fmt)) {
 			if (try_fmt.fmt.pix.pixelformat == supported_src_pixfmts[i].fmt) {
 				int size_x_diff = abs((int)try_fmt.fmt.pix.width -
 						(int)dest_fmt->fmt.pix.width);
@@ -381,7 +383,7 @@  int v4lconvert_try_format(struct v4lconvert_data *data,
 	if (!v4lconvert_supported_dst_format(dest_fmt->fmt.pix.pixelformat) ||
 			dest_fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
 			v4lconvert_do_try_format(data, &try_dest, &try_src)) {
-		result = SYS_IOCTL(data->fd, VIDIOC_TRY_FMT, dest_fmt);
+		result = data->dev_ops->ioctl(data->fd, VIDIOC_TRY_FMT, dest_fmt);
 		if (src_fmt)
 			*src_fmt = *dest_fmt;
 		return result;
@@ -1236,7 +1238,7 @@  static void v4lconvert_get_framesizes(struct v4lconvert_data *data,
 
 	for (i = 0; ; i++) {
 		frmsize.index = i;
-		if (SYS_IOCTL(data->fd, VIDIOC_ENUM_FRAMESIZES, &frmsize))
+		if (data->dev_ops->ioctl(data->fd, VIDIOC_ENUM_FRAMESIZES, &frmsize))
 			break;
 
 		/* We got a framesize, check we don't have the same one already */
@@ -1296,7 +1298,7 @@  int v4lconvert_enum_framesizes(struct v4lconvert_data *data,
 			errno = EINVAL;
 			return -1;
 		}
-		return SYS_IOCTL(data->fd, VIDIOC_ENUM_FRAMESIZES, frmsize);
+		return data->dev_ops->ioctl(data->fd, VIDIOC_ENUM_FRAMESIZES, frmsize);
 	}
 
 	if (frmsize->index >= data->no_framesizes) {
@@ -1332,7 +1334,8 @@  int v4lconvert_enum_frameintervals(struct v4lconvert_data *data,
 			errno = EINVAL;
 			return -1;
 		}
-		res = SYS_IOCTL(data->fd, VIDIOC_ENUM_FRAMEINTERVALS, frmival);
+		res = data->dev_ops->ioctl(data->fd, VIDIOC_ENUM_FRAMEINTERVALS,
+				frmival);
 		if (res)
 			V4LCONVERT_ERR("%s\n", strerror(errno));
 		return res;
@@ -1377,7 +1380,7 @@  int v4lconvert_enum_frameintervals(struct v4lconvert_data *data,
 	frmival->pixel_format = src_fmt.fmt.pix.pixelformat;
 	frmival->width = src_fmt.fmt.pix.width;
 	frmival->height = src_fmt.fmt.pix.height;
-	res = SYS_IOCTL(data->fd, VIDIOC_ENUM_FRAMEINTERVALS, frmival);
+	res = data->dev_ops->ioctl(data->fd, VIDIOC_ENUM_FRAMEINTERVALS, frmival);
 	if (res) {
 		int dest_pixfmt = dest_fmt.fmt.pix.pixelformat;
 		int src_pixfmt  = src_fmt.fmt.pix.pixelformat;