v4l2: duplicate InitVideo() for access and access_demux

There is not that much common code left for the access case, except for
debug messages. The resulting code is a lot easier to read IMHO.
Also I have no way to test the access plugin, so lets split it where it
will not get more broken.

modules/access/v4l2/access.c

@@ -27,6 +27,7 @@
 # include "config.h"
 #endif
 
+#include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <poll.h>
@@ -40,6 +41,7 @@
 static block_t *AccessRead( access_t * );
 static ssize_t AccessReadStream( access_t *, uint8_t *, size_t );
 static int AccessControl( access_t *, int, va_list );
+static int InitVideo(access_t *, int);
 
 int AccessOpen( vlc_object_t *obj )
 {
@@ -76,7 +78,7 @@ int AccessOpen( vlc_object_t *obj )
         fd = rawfd;
     }
 
-    if (InitVideo (obj, fd, sys, false))
+    if (InitVideo (access, fd))
     {
         v4l2_close (fd);
         goto error;
@@ -95,6 +97,127 @@ error:
     return VLC_EGENERIC;
 }
 
+int InitVideo (access_t *access, int fd)
+{
+    demux_sys_t *sys = (demux_sys_t *)access->p_sys;
+    unsigned int i_min;
+    enum v4l2_buf_type buf_type;
+
+    /* Get device capabilites */
+    struct v4l2_capability cap;
+    if (v4l2_ioctl (fd, VIDIOC_QUERYCAP, &cap) < 0)
+    {
+        msg_Err (access, "cannot get device capabilities: %m");
+        return -1;
+    }
+
+    msg_Dbg (access, "device %s using driver %s (version %u.%u.%u) on %s",
+             cap.card, cap.driver, (cap.version >> 16) & 0xFF,
+             (cap.version >> 8) & 0xFF, cap.version & 0xFF, cap.bus_info);
+    msg_Dbg (access, "the device has the capabilities: 0x%08X",
+             cap.capabilities);
+    msg_Dbg (access, " (%c) Video Capture, (%c) Audio, (%c) Tuner, (%c) Radio",
+             (cap.capabilities & V4L2_CAP_VIDEO_CAPTURE  ? 'X':' '),
+             (cap.capabilities & V4L2_CAP_AUDIO  ? 'X':' '),
+             (cap.capabilities & V4L2_CAP_TUNER  ? 'X':' '),
+             (cap.capabilities & V4L2_CAP_RADIO  ? 'X':' '));
+    msg_Dbg (access, " (%c) Read/Write, (%c) Streaming, (%c) Asynchronous",
+             (cap.capabilities & V4L2_CAP_READWRITE ? 'X':' '),
+             (cap.capabilities & V4L2_CAP_STREAMING ? 'X':' '),
+             (cap.capabilities & V4L2_CAP_ASYNCIO ? 'X':' '));
+
+    if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE))
+    {
+        msg_Err (access, "not a video capture device");
+        return -1;
+    }
+
+    if (cap.capabilities & V4L2_CAP_STREAMING)
+        sys->io = IO_METHOD_MMAP;
+    else if (cap.capabilities & V4L2_CAP_READWRITE)
+        sys->io = IO_METHOD_READ;
+    else
+    {
+        msg_Err (access, "no supported I/O method");
+        return -1;
+    }
+
+    if (SetupInput (VLC_OBJECT(access), fd))
+        return -1;
+
+    sys->controls = ControlsInit (VLC_OBJECT(access), fd);
+
+    /* Try and find default resolution if not specified */
+    struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
+    if (v4l2_ioctl (fd, VIDIOC_G_FMT, &fmt) < 0)
+    {
+        msg_Err (access, "cannot get default format: %m");
+        return -1;
+    }
+
+    /* Print extra info */
+    msg_Dbg (access, "%d bytes maximum for complete image",
+             fmt.fmt.pix.sizeimage );
+    /* Check interlacing */
+    switch (fmt.fmt.pix.field)
+    {
+        case V4L2_FIELD_INTERLACED:
+            msg_Dbg (access, "Interlacing setting: interleaved");
+            /*if (NTSC)
+                sys->i_block_flags = BLOCK_FLAG_BOTTOM_FIELD_FIRST;
+            else*/
+                sys->i_block_flags = BLOCK_FLAG_TOP_FIELD_FIRST;
+            break;
+        case V4L2_FIELD_INTERLACED_TB:
+            msg_Dbg (access, "Interlacing setting: interleaved top bottom" );
+            sys->i_block_flags = BLOCK_FLAG_TOP_FIELD_FIRST;
+            break;
+        case V4L2_FIELD_INTERLACED_BT:
+            msg_Dbg (access, "Interlacing setting: interleaved bottom top" );
+            sys->i_block_flags = BLOCK_FLAG_BOTTOM_FIELD_FIRST;
+            break;
+        default:
+            break;
+    }
+
+    /* Init I/O method */
+    switch (sys->io)
+    {
+    case IO_METHOD_READ:
+        sys->blocksize = fmt.fmt.pix.sizeimage;
+        break;
+
+    case IO_METHOD_MMAP:
+        if (InitMmap (VLC_OBJECT(access), sys, fd))
+            return -1;
+        for (unsigned int i = 0; i < sys->i_nbuffers; i++)
+        {
+            struct v4l2_buffer buf = {
+                .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
+                .memory = V4L2_MEMORY_MMAP,
+                .index = i,
+            };
+
+            if (v4l2_ioctl (fd, VIDIOC_QBUF, &buf) < 0)
+            {
+                msg_Err (access, "cannot queue buffer: %m");
+                return -1;
+            }
+        }
+
+        buf_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        if (v4l2_ioctl (fd, VIDIOC_STREAMON, &buf_type) < 0)
+        {
+            msg_Err (access, "cannot start streaming: %m" );
+            return -1;
+        }
+        break;
+    default:
+        assert (0);
+    }
+    return 0;
+}
+
 void AccessClose( vlc_object_t *obj )
 {
     access_t *access = (access_t *)obj;

modules/access/v4l2/v4l2.h

@@ -110,8 +110,9 @@ struct buffer_t
 
 /* video.c */
 void ParseMRL(vlc_object_t *, const char *);
+int SetupInput (vlc_object_t *, int fd);
+int InitMmap (vlc_object_t *, demux_sys_t *, int);
 block_t* GrabVideo(vlc_object_t *, demux_sys_t *);
-int InitVideo(vlc_object_t *, int fd, demux_sys_t *, bool demux);
 
 /* demux.c */
 int DemuxOpen(vlc_object_t *);