[PATCH] add v4l2 api

This adds the v4l2 API to the linux kernel.

The first, original video4linux API has a number of design bugs.  They
are fixed in this new API revision.  It already exists for quite some
time.  Last weeks it got a number of cleanups based on the experiences
of the last years (drop stuff nobody uses, fix some inconsistencies).
We consider it being in a pretty good shape now and like to see it in
2.6.

This patch is basically the header file with all the structs and ioctls
in there.  A small module with some helper functions for v4l2 drivers is
included too.  Related updates (bttv, ...) will follow as separate
patches.

drivers/media/Kconfig

@@ -12,9 +12,14 @@ config VIDEO_DEV
 	  this are available from
 	  <ftp://ftp.uk.linux.org/pub/linux/video4linux/>.
 
-	  If you are interested in writing a driver for such an audio/video
-	  device or user software interacting with such a driver, please read
-	  the file <file:Documentation/video4linux/API.html>.
+	  This kernel includes support for the new Video for Linux Two API,
+	  (V4L2) as well as the original system. Drivers and applications
+	  need to be rewritten to use V4L2, but drivers for popular cards
+	  and applications for most video capture functions already exist.
+
+	  Documentation for the original API is included in the file
+	  Documentation/video4linux/API.html.  Documentation for V4L2 is
+	  available on the web at http://bytesex.org/v4l/
 
 	  This driver is also available as a module called videodev.o ( = code
 	  which can be inserted in and removed from the running kernel

drivers/media/video/Makefile

@@ -5,13 +5,14 @@
 # All of the (potential) objects that export symbols.
 # This list comes from 'grep -l EXPORT_SYMBOL *.[hc]'.
 
-export-objs     :=	videodev.o bttv-if.o cpia.o video-buf.o
+export-objs     :=	videodev.o v4l2-common.o \
+			bttv-if.o cpia.o video-buf.o
 
 bttv-objs	:=	bttv-driver.o bttv-cards.o bttv-if.o \
 			bttv-risc.o bttv-vbi.o
 zoran-objs      :=	zr36120.o zr36120_i2c.o zr36120_mem.o
 
-obj-$(CONFIG_VIDEO_DEV) += videodev.o
+obj-$(CONFIG_VIDEO_DEV) += videodev.o v4l2-common.o
 
 obj-$(CONFIG_VIDEO_BT848) += bttv.o msp3400.o tvaudio.o \
 	tda7432.o tda9875.o tuner.o video-buf.o

drivers/media/video/v4l2-common.c

+/*
+ *	Video for Linux Two
+ *
+ *	A generic video device interface for the LINUX operating system
+ *	using a set of device structures/vectors for low level operations.
+ *
+ *	This file replaces the videodev.c file that comes with the
+ *	regular kernel distribution.
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ *
+ * Author:	Bill Dirks <bdirks@pacbell.net>
+ *		based on code by Alan Cox, <alan@cymru.net>
+ *
+ */
+
+/*
+ * Video capture interface for Linux
+ *
+ *	A generic video device interface for the LINUX operating system
+ *	using a set of device structures/vectors for low level operations.
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Author:	Alan Cox, <alan@redhat.com>
+ *
+ * Fixes:
+ */
+
+/*
+ * Video4linux 1/2 integration by Justin Schoeman
+ * <justin@suntiger.ee.up.ac.za>
+ * 2.4 PROCFS support ported from 2.4 kernels by 
+ *  Iaki Garca Etxebarria <garetxe@euskalnet.net>
+ * Makefile fix by "W. Michael Petullo" <mike@flyn.org>
+ * 2.4 devfs support ported from 2.4 kernels by
+ *  Dan Merillat <dan@merillat.org>
+ * Added Gerd Knorrs v4l1 enhancements (Justin Schoeman)
+ */
+
+#include <linux/config.h>
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/smp_lock.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/pgtable.h>
+#include <asm/io.h>
+#include <asm/div64.h>
+
+#ifdef CONFIG_KMOD
+#include <linux/kmod.h>
+#endif
+
+#if defined(CONFIG_UST) || defined(CONFIG_UST_MODULE)
+#include <linux/ust.h>
+#endif
+
+#include <linux/videodev.h>
+
+MODULE_AUTHOR("Bill Dirks, Justin Schoeman, Gerd Knorr");
+MODULE_DESCRIPTION("misc helper functions for v4l2 device drivers");
+MODULE_LICENSE("GPL");
+
+/*
+ *
+ *	V 4 L 2   D R I V E R   H E L P E R   A P I
+ *
+ */
+
+/*
+ *  Video Standard Operations (contributed by Michael Schimek)
+ */
+
+/* This is the recommended method to deal with the framerate fields. More 
+   sophisticated drivers will access the fields directly. */
+unsigned int
+v4l2_video_std_fps(struct v4l2_standard *vs)
+{ 
+	if (vs->frameperiod.numerator > 0)
+		return (((vs->frameperiod.denominator << 8) / 
+			 vs->frameperiod.numerator) + 
+			(1 << 7)) / (1 << 8);
+	return 0;
+}
+
+/* Fill in the fields of a v4l2_standard structure according to the
+   'id' and 'transmission' parameters.  Returns negative on error.  */
+int v4l2_video_std_construct(struct v4l2_standard *vs,
+			     int id, char *name)
+{
+	memset(vs, 0, sizeof(struct v4l2_standard));
+
+	vs->id = id;
+	if (id & (V4L2_STD_NTSC | V4L2_STD_PAL_M)) {
+		vs->frameperiod.numerator = 1001;
+		vs->frameperiod.denominator = 30000;
+		vs->framelines = 525;
+	} else {
+		vs->frameperiod.numerator = 1;
+		vs->frameperiod.denominator = 25;
+		vs->framelines = 625;
+	}
+	strncpy(vs->name,name,sizeof(vs->name));
+	return 0;
+}
+
+
+/* ----------------------------------------------------------------- */
+
+char *v4l2_field_names[] = {
+	[V4L2_FIELD_ANY]        = "any",
+	[V4L2_FIELD_NONE]       = "none",
+	[V4L2_FIELD_TOP]        = "top",
+	[V4L2_FIELD_BOTTOM]     = "bottom",
+	[V4L2_FIELD_INTERLACED] = "interlaced",
+	[V4L2_FIELD_SEQ_TB]     = "seq-tb",
+	[V4L2_FIELD_SEQ_BT]     = "seq-bt",
+	[V4L2_FIELD_ALTERNATE]  = "alternate",
+};
+
+char *v4l2_type_names[] = {
+	[V4L2_BUF_TYPE_VIDEO_CAPTURE] = "video-cap",
+	[V4L2_BUF_TYPE_VIDEO_OVERLAY] = "video-over",
+	[V4L2_BUF_TYPE_VIDEO_OUTPUT]  = "video-out",
+	[V4L2_BUF_TYPE_VBI_CAPTURE]   = "vbi-cap",
+	[V4L2_BUF_TYPE_VBI_OUTPUT]    = "vbi-out",
+};
+
+char *v4l2_ioctl_names[256] = {
+#if __GNUC__ >= 3
+	[0 ... 255]                      = "UNKNOWN",
+#endif
+	[_IOC_NR(VIDIOC_QUERYCAP)]       = "VIDIOC_QUERYCAP",
+	[_IOC_NR(VIDIOC_RESERVED)]       = "VIDIOC_RESERVED",
+	[_IOC_NR(VIDIOC_ENUM_FMT)]       = "VIDIOC_ENUM_FMT",
+	[_IOC_NR(VIDIOC_G_FMT)]          = "VIDIOC_G_FMT",
+	[_IOC_NR(VIDIOC_S_FMT)]          = "VIDIOC_S_FMT",
+#if 0
+	[_IOC_NR(VIDIOC_G_COMP)]         = "VIDIOC_G_COMP",
+	[_IOC_NR(VIDIOC_S_COMP)]         = "VIDIOC_S_COMP",
+#endif
+	[_IOC_NR(VIDIOC_REQBUFS)]        = "VIDIOC_REQBUFS",
+	[_IOC_NR(VIDIOC_QUERYBUF)]       = "VIDIOC_QUERYBUF",
+	[_IOC_NR(VIDIOC_G_FBUF)]         = "VIDIOC_G_FBUF",
+	[_IOC_NR(VIDIOC_S_FBUF)]         = "VIDIOC_S_FBUF",
+	[_IOC_NR(VIDIOC_OVERLAY)]        = "VIDIOC_OVERLAY",
+	[_IOC_NR(VIDIOC_QBUF)]           = "VIDIOC_QBUF",
+	[_IOC_NR(VIDIOC_DQBUF)]          = "VIDIOC_DQBUF",
+	[_IOC_NR(VIDIOC_STREAMON)]       = "VIDIOC_STREAMON",
+	[_IOC_NR(VIDIOC_STREAMOFF)]      = "VIDIOC_STREAMOFF",
+	[_IOC_NR(VIDIOC_G_PARM)]         = "VIDIOC_G_PARM",
+	[_IOC_NR(VIDIOC_S_PARM)]         = "VIDIOC_S_PARM",
+	[_IOC_NR(VIDIOC_G_STD)]          = "VIDIOC_G_STD",
+	[_IOC_NR(VIDIOC_S_STD)]          = "VIDIOC_S_STD",
+	[_IOC_NR(VIDIOC_ENUMSTD)]        = "VIDIOC_ENUMSTD",
+	[_IOC_NR(VIDIOC_ENUMINPUT)]      = "VIDIOC_ENUMINPUT",
+	[_IOC_NR(VIDIOC_G_CTRL)]         = "VIDIOC_G_CTRL",
+	[_IOC_NR(VIDIOC_S_CTRL)]         = "VIDIOC_S_CTRL",
+	[_IOC_NR(VIDIOC_G_TUNER)]        = "VIDIOC_G_TUNER",
+	[_IOC_NR(VIDIOC_S_TUNER)]        = "VIDIOC_S_TUNER",
+	[_IOC_NR(VIDIOC_G_AUDIO)]        = "VIDIOC_G_AUDIO",
+	[_IOC_NR(VIDIOC_S_AUDIO)]        = "VIDIOC_S_AUDIO",
+	[_IOC_NR(VIDIOC_QUERYCTRL)]      = "VIDIOC_QUERYCTRL",
+	[_IOC_NR(VIDIOC_QUERYMENU)]      = "VIDIOC_QUERYMENU",
+	[_IOC_NR(VIDIOC_G_INPUT)]        = "VIDIOC_G_INPUT",
+	[_IOC_NR(VIDIOC_S_INPUT)]        = "VIDIOC_S_INPUT",
+	[_IOC_NR(VIDIOC_G_OUTPUT)]       = "VIDIOC_G_OUTPUT",
+	[_IOC_NR(VIDIOC_S_OUTPUT)]       = "VIDIOC_S_OUTPUT",
+	[_IOC_NR(VIDIOC_ENUMOUTPUT)]     = "VIDIOC_ENUMOUTPUT",
+	[_IOC_NR(VIDIOC_G_AUDOUT)]       = "VIDIOC_G_AUDOUT",
+	[_IOC_NR(VIDIOC_S_AUDOUT)]       = "VIDIOC_S_AUDOUT",
+	[_IOC_NR(VIDIOC_G_MODULATOR)]    = "VIDIOC_G_MODULATOR",
+	[_IOC_NR(VIDIOC_S_MODULATOR)]    = "VIDIOC_S_MODULATOR",
+	[_IOC_NR(VIDIOC_G_FREQUENCY)]    = "VIDIOC_G_FREQUENCY",
+	[_IOC_NR(VIDIOC_S_FREQUENCY)]    = "VIDIOC_S_FREQUENCY",
+	[_IOC_NR(VIDIOC_CROPCAP)]        = "VIDIOC_CROPCAP",
+	[_IOC_NR(VIDIOC_G_CROP)]         = "VIDIOC_G_CROP",
+	[_IOC_NR(VIDIOC_S_CROP)]         = "VIDIOC_S_CROP",
+	[_IOC_NR(VIDIOC_G_JPEGCOMP)]     = "VIDIOC_G_JPEGCOMP",
+	[_IOC_NR(VIDIOC_S_JPEGCOMP)]     = "VIDIOC_S_JPEGCOMP",
+	[_IOC_NR(VIDIOC_QUERYSTD)]       = "VIDIOC_QUERYSTD",
+	[_IOC_NR(VIDIOC_TRY_FMT)]        = "VIDIOC_TRY_FMT",
+};
+
+/* ----------------------------------------------------------------- */
+
+EXPORT_SYMBOL(v4l2_video_std_fps);
+EXPORT_SYMBOL(v4l2_video_std_construct);
+
+EXPORT_SYMBOL(v4l2_field_names);
+EXPORT_SYMBOL(v4l2_type_names);
+EXPORT_SYMBOL(v4l2_ioctl_names);
+
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */

include/linux/videodev.h

@@ -4,10 +4,10 @@
 #include <linux/types.h>
 #include <linux/version.h>
 
-#if 0
+#if 1
 /*
  * v4l2 is still work-in-progress, integration planed for 2.5.x
- *   v4l2 project homepage:   http://www.thedirks.org/v4l2/
+ *   documentation:           http://bytesex.org/v4l/
  *   patches available from:  http://bytesex.org/patches/
  */ 
 # define HAVE_V4L2 1
@@ -32,10 +32,7 @@ struct video_device
 	int minor;
 
  	/* 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 */
+ 	 * like soundcore does. */
  	struct file_operations *fops;
 	void *priv;		/* Used to be 'private' but that upsets C++ */