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path: root/drivers/media/usb/uvc/uvc_video.c
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Diffstat (limited to 'drivers/media/usb/uvc/uvc_video.c')
-rw-r--r--drivers/media/usb/uvc/uvc_video.c59
1 files changed, 55 insertions, 4 deletions
diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
index e00f38dd07d9..e3567aeb0007 100644
--- a/drivers/media/usb/uvc/uvc_video.c
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -20,6 +20,7 @@
#include <linux/atomic.h>
#include <linux/unaligned.h>
+#include <media/jpeg.h>
#include <media/v4l2-common.h>
#include "uvcvideo.h"
@@ -79,6 +80,27 @@ int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
if (likely(ret == size))
return 0;
+ /*
+ * Some devices return shorter USB control packets than expected if the
+ * returned value can fit in less bytes. Zero all the bytes that the
+ * device has not written.
+ *
+ * This quirk is applied to all controls, regardless of their data type.
+ * Most controls are little-endian integers, in which case the missing
+ * bytes become 0 MSBs. For other data types, a different heuristic
+ * could be implemented if a device is found needing it.
+ *
+ * We exclude UVC_GET_INFO from the quirk. UVC_GET_LEN does not need
+ * to be excluded because its size is always 1.
+ */
+ if (ret > 0 && query != UVC_GET_INFO) {
+ memset(data + ret, 0, size - ret);
+ dev_warn_once(&dev->udev->dev,
+ "UVC non compliance: %s control %u on unit %u returned %d bytes when we expected %u.\n",
+ uvc_query_name(query), cs, unit, ret, size);
+ return 0;
+ }
+
if (ret != -EPIPE) {
dev_err(&dev->udev->dev,
"Failed to query (%s) UVC control %u on unit %u: %d (exp. %u).\n",
@@ -96,8 +118,12 @@ int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
error = *(u8 *)data;
*(u8 *)data = tmp;
- if (ret != 1)
+ if (ret != 1) {
+ dev_err_ratelimited(&dev->udev->dev,
+ "Failed to query (%s) UVC error code control %u on unit %u: %d (exp. 1).\n",
+ uvc_query_name(query), cs, unit, ret);
return ret < 0 ? ret : -EPIPE;
+ }
uvc_dbg(dev, CONTROL, "Control error %u\n", error);
@@ -297,8 +323,9 @@ static int uvc_get_video_ctrl(struct uvc_streaming *stream,
goto out;
} else if (ret != size) {
dev_err(&stream->intf->dev,
- "Failed to query (%u) UVC %s control : %d (exp. %u).\n",
- query, probe ? "probe" : "commit", ret, size);
+ "Failed to query (%s) UVC %s control : %d (exp. %u).\n",
+ uvc_query_name(query), probe ? "probe" : "commit",
+ ret, size);
ret = (ret == -EPROTO) ? -EPROTO : -EIO;
goto out;
}
@@ -1116,6 +1143,7 @@ static void uvc_video_stats_stop(struct uvc_streaming *stream)
static int uvc_video_decode_start(struct uvc_streaming *stream,
struct uvc_buffer *buf, const u8 *data, int len)
{
+ u8 header_len;
u8 fid;
/*
@@ -1129,6 +1157,7 @@ static int uvc_video_decode_start(struct uvc_streaming *stream,
return -EINVAL;
}
+ header_len = data[0];
fid = data[1] & UVC_STREAM_FID;
/*
@@ -1210,9 +1239,31 @@ static int uvc_video_decode_start(struct uvc_streaming *stream,
return -EAGAIN;
}
+ /*
+ * Some cameras, when running two parallel streams (one MJPEG alongside
+ * another non-MJPEG stream), are known to lose the EOF packet for a frame.
+ * We can detect the end of a frame by checking for a new SOI marker, as
+ * the SOI always lies on the packet boundary between two frames for
+ * these devices.
+ */
+ if (stream->dev->quirks & UVC_QUIRK_MJPEG_NO_EOF &&
+ (stream->cur_format->fcc == V4L2_PIX_FMT_MJPEG ||
+ stream->cur_format->fcc == V4L2_PIX_FMT_JPEG)) {
+ const u8 *packet = data + header_len;
+
+ if (len >= header_len + 2 &&
+ packet[0] == 0xff && packet[1] == JPEG_MARKER_SOI &&
+ buf->bytesused != 0) {
+ buf->state = UVC_BUF_STATE_READY;
+ buf->error = 1;
+ stream->last_fid ^= UVC_STREAM_FID;
+ return -EAGAIN;
+ }
+ }
+
stream->last_fid = fid;
- return data[0];
+ return header_len;
}
static inline enum dma_data_direction uvc_stream_dir(