V4L/DVB (12169): em28xx-video: fix VIDIOC_G_FMT and VIDIOC_ENUMFMT with webcams

Webcams have different constraints than other v4l devices. This patch
makes the format ioctls to behave better. It also fixes a bug at open()
handler, that were always reseting resolution to the maximum available
one.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 49 insertions, 30 deletions

diff --git a/drivers/media/video/em28xx/em28xx-video.c b/drivers/media/video/em28xx/em28xx-video.c
index b96a138d9d03..702fe8d6742e 100644
--- a/drivers/media/video/em28xx/em28xx-video.c
+++ b/drivers/media/video/em28xx/em28xx-video.c
@@ -746,13 +746,41 @@ static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
         return 0;
 }
 
+static int em28xx_set_video_format(struct em28xx *dev, unsigned int fourcc,
+                                   unsigned width, unsigned height)
+{
+        struct em28xx_fmt     *fmt;
+
+        /* FIXME: This is the only supported fmt */
+        if (dev->board.is_27xx) {
+                fourcc = V4L2_PIX_FMT_RGB565;
+                width  = 640;
+                height = 480;
+        }
+
+        fmt = format_by_fourcc(fourcc);
+        if (!fmt)
+                return -EINVAL;
+
+        dev->format = fmt;
+        dev->width  = width;
+        dev->height = height;
+
+        /* set new image size */
+        get_scale(dev, dev->width, dev->height, &dev->hscale, &dev->vscale);
+
+        em28xx_set_alternate(dev);
+        em28xx_resolution_set(dev);
+
+        return 0;
+}
+
 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
                         struct v4l2_format *f)
 {
         struct em28xx_fh      *fh  = priv;
         struct em28xx         *dev = fh->dev;
         int                   rc;
-        struct em28xx_fmt     *fmt;
 
         rc = check_dev(dev);
         if (rc < 0)
@@ -760,18 +788,8 @@ static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
 
         mutex_lock(&dev->lock);
 
-        /* FIXME: This is the only supported fmt */
-        if (dev->board.is_27xx)
-                f->fmt.pix.pixelformat = V4L2_PIX_FMT_RGB565;
-
         vidioc_try_fmt_vid_cap(file, priv, f);
 
-        fmt = format_by_fourcc(f->fmt.pix.pixelformat);
-        if (!fmt) {
-                rc = -EINVAL;
-                goto out;
-        }
-
         if (videobuf_queue_is_busy(&fh->vb_vidq)) {
                 em28xx_errdev("%s queue busy\n", __func__);
                 rc = -EBUSY;
@@ -784,16 +802,8 @@ static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
                 goto out;
         }
 
-        /* set new image size */
-        dev->width = f->fmt.pix.width;
-        dev->height = f->fmt.pix.height;
-        dev->format = fmt;
-        get_scale(dev, dev->width, dev->height, &dev->hscale, &dev->vscale);
-
-        em28xx_set_alternate(dev);
-        em28xx_resolution_set(dev);
-
-        rc = 0;
+        rc = em28xx_set_video_format(dev, f->fmt.pix.pixelformat,
+                                f->fmt.pix.width, f->fmt.pix.height);
 
 out:
         mutex_unlock(&dev->lock);
@@ -1377,9 +1387,24 @@ static int vidioc_querycap(struct file *file, void  *priv,
 static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
                                         struct v4l2_fmtdesc *f)
 {
+        struct em28xx_fh      *fh  = priv;
+        struct em28xx         *dev = fh->dev;
+
         if (unlikely(f->index >= ARRAY_SIZE(format)))
                 return -EINVAL;
 
+        if (dev->board.is_27xx) {
+                struct em28xx_fmt *fmt;
+                if (f->index)
+                        return -EINVAL;
+
+                f->pixelformat = V4L2_PIX_FMT_RGB565;
+                fmt = format_by_fourcc(f->pixelformat);
+                strlcpy(f->description, fmt->name, sizeof(f->description));
+
+                return 0;
+        }
+
         strlcpy(f->description, format[f->index].name, sizeof(f->description));
         f->pixelformat = format[f->index].fourcc;
 
@@ -1633,11 +1658,6 @@ static int em28xx_v4l2_open(struct file *filp)
         filp->private_data = fh;
 
         if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE && dev->users == 0) {
-                dev->width = norm_maxw(dev);
-                dev->height = norm_maxh(dev);
-                dev->hscale = 0;
-                dev->vscale = 0;
-
                 em28xx_set_mode(dev, EM28XX_ANALOG_MODE);
                 em28xx_set_alternate(dev);
                 em28xx_resolution_set(dev);
@@ -1979,15 +1999,14 @@ int em28xx_register_analog_devices(struct em28xx *dev)
 
         /* set default norm */
         dev->norm = em28xx_video_template.current_norm;
-        dev->width = norm_maxw(dev);
-        dev->height = norm_maxh(dev);
         dev->interlaced = EM28XX_INTERLACED_DEFAULT;
-        dev->hscale = 0;
-        dev->vscale = 0;
         dev->ctl_input = 0;
 
         /* Analog specific initialization */
         dev->format = &format[0];
+        em28xx_set_video_format(dev, format[0].fourcc,
+                                norm_maxw(dev), norm_maxh(dev));
+
         video_mux(dev, dev->ctl_input);
 
         /* Audio defaults */