[media] hdpvr: improve error handling

get_video_info() should never return EFAULT, instead it should return
the low-level usb_control_msg() error. Add a valid field to the hdpvr_video_info
struct so the driver can easily check if a valid format was detected.
Whenever get_video_info is called and it returns an error (e.g. usb_control_msg
failed), then return that error to userspace as well.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/usb/hdpvr/hdpvr-control.c b/drivers/media/usb/hdpvr/hdpvr-control.c
index df6bcb524d80e456c0db3dc93802a1880ac450f4..6053661dc04bd39727021c311f7d80f1d37ca60a 100644 (file)
--- a/drivers/media/usb/hdpvr/hdpvr-control.c
+++ b/drivers/media/usb/hdpvr/hdpvr-control.c
@@ -49,6 +49,7 @@ int get_video_info(struct hdpvr_device *dev, struct hdpvr_video_info *vidinf)
 {
        int ret;
 
+       vidinf->valid = false;
        mutex_lock(&dev->usbc_mutex);
        ret = usb_control_msg(dev->udev,
                              usb_rcvctrlpipe(dev->udev, 0),
@@ -56,11 +57,6 @@ int get_video_info(struct hdpvr_device *dev, struct hdpvr_video_info *vidinf)
                              0x1400, 0x0003,
                              dev->usbc_buf, 5,
                              1000);
-       if (ret == 5) {
-               vidinf->width   = dev->usbc_buf[1] << 8 | dev->usbc_buf[0];
-               vidinf->height  = dev->usbc_buf[3] << 8 | dev->usbc_buf[2];
-               vidinf->fps     = dev->usbc_buf[4];
-       }
 
 #ifdef HDPVR_DEBUG
        if (hdpvr_debug & MSG_INFO) {
@@ -73,14 +69,15 @@ int get_video_info(struct hdpvr_device *dev, struct hdpvr_video_info *vidinf)
 #endif
        mutex_unlock(&dev->usbc_mutex);
 
-       if ((ret > 0 && ret != 5) ||/* fail if unexpected byte count returned */
-           !vidinf->width ||   /* preserve original behavior -  */
-           !vidinf->height ||  /* fail if no signal is detected */
-           !vidinf->fps) {
-               ret = -EFAULT;
-       }
+       if (ret < 0)
+               return ret;
 
-       return ret < 0 ? ret : 0;
+       vidinf->width   = dev->usbc_buf[1] << 8 | dev->usbc_buf[0];
+       vidinf->height  = dev->usbc_buf[3] << 8 | dev->usbc_buf[2];
+       vidinf->fps     = dev->usbc_buf[4];
+       vidinf->valid   = vidinf->width && vidinf->height && vidinf->fps;
+
+       return 0;
 }
 
 int get_input_lines_info(struct hdpvr_device *dev)

diff --git a/drivers/media/usb/hdpvr/hdpvr-video.c b/drivers/media/usb/hdpvr/hdpvr-video.c
index e9471059056e21f152b3ac013acd5813864ade25..4f8567aa99d8fb357f7337b66af092fa846caac2 100644 (file)
--- a/drivers/media/usb/hdpvr/hdpvr-video.c
+++ b/drivers/media/usb/hdpvr/hdpvr-video.c
@@ -285,7 +285,10 @@ static int hdpvr_start_streaming(struct hdpvr_device *dev)
                return -EAGAIN;
 
        ret = get_video_info(dev, &vidinf);
-       if (ret) {
+       if (ret < 0)
+               return ret;
+
+       if (!vidinf.valid) {
                msleep(250);
                v4l2_dbg(MSG_INFO, hdpvr_debug, &dev->v4l2_dev,
                                "no video signal at input %d\n", dev->options.video_input);
@@ -617,15 +620,12 @@ static int vidioc_querystd(struct file *file, void *_fh, v4l2_std_id *a)
        if (dev->options.video_input == HDPVR_COMPONENT)
                return fh->legacy_mode ? 0 : -ENODATA;
        ret = get_video_info(dev, &vid_info);
-       if (ret)
-               return 0;
-       if (vid_info.width == 720 &&
+       if (vid_info.valid && vid_info.width == 720 &&
            (vid_info.height == 480 || vid_info.height == 576)) {
                *a = (vid_info.height == 480) ?
                        V4L2_STD_525_60 : V4L2_STD_625_50;
        }
-
-       return 0;
+       return ret;
 }
 
 static int vidioc_s_dv_timings(struct file *file, void *_fh,
@@ -679,6 +679,8 @@ static int vidioc_query_dv_timings(struct file *file, void *_fh,
                return -ENODATA;
        ret = get_video_info(dev, &vid_info);
        if (ret)
+               return ret;
+       if (!vid_info.valid)
                return -ENOLCK;
        interlaced = vid_info.fps <= 30;
        for (i = 0; i < ARRAY_SIZE(hdpvr_dv_timings); i++) {
@@ -1008,7 +1010,9 @@ static int vidioc_g_fmt_vid_cap(struct file *file, void *_fh,
                struct hdpvr_video_info vid_info;
 
                ret = get_video_info(dev, &vid_info);
-               if (ret)
+               if (ret < 0)
+                       return ret;
+               if (!vid_info.valid)
                        return -EFAULT;
                f->fmt.pix.width = vid_info.width;
                f->fmt.pix.height = vid_info.height;

diff --git a/drivers/media/usb/hdpvr/hdpvr.h b/drivers/media/usb/hdpvr/hdpvr.h
index 808ea7a0efe5744037a80a2859aad350605cbbe5..dc685d44cb3e4ef24284f9807c966af7e85a35a8 100644 (file)
--- a/drivers/media/usb/hdpvr/hdpvr.h
+++ b/drivers/media/usb/hdpvr/hdpvr.h
@@ -154,6 +154,7 @@ struct hdpvr_video_info {
        u16     width;
        u16     height;
        u8      fps;
+       bool    valid;
 };
 
 enum {