V4L/DVB (11105): gspca - ov534: Adjust the packet scan function
- change max payload size to 2040 bytes (was 2048)
- optimize
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/gspca/ov534.c b/drivers/media/video/gspca/ov534.c
index ea22456..647c448 100644
--- a/drivers/media/video/gspca/ov534.c
+++ b/drivers/media/video/gspca/ov534.c
@@ -46,9 +46,9 @@
/* specific webcam descriptor */
struct sd {
struct gspca_dev gspca_dev; /* !! must be the first item */
- __u32 last_fid;
__u32 last_pts;
- int frame_rate;
+ u16 last_fid;
+ u8 frame_rate;
};
/* V4L2 controls supported by the driver */
@@ -428,76 +428,75 @@
{
struct sd *sd = (struct sd *) gspca_dev;
__u32 this_pts;
- int this_fid;
+ u16 this_fid;
int remaining_len = len;
- __u8 *next_data = data;
-scan_next:
- if (remaining_len <= 0)
- return;
+ do {
+ len = min(remaining_len, 2040); /*fixme: was 2048*/
- data = next_data;
- len = min(remaining_len, 2048);
- remaining_len -= len;
- next_data += len;
+ /* Payloads are prefixed with a UVC-style header. We
+ consider a frame to start when the FID toggles, or the PTS
+ changes. A frame ends when EOF is set, and we've received
+ the correct number of bytes. */
- /* Payloads are prefixed with a UVC-style header. We
- consider a frame to start when the FID toggles, or the PTS
- changes. A frame ends when EOF is set, and we've received
- the correct number of bytes. */
-
- /* Verify UVC header. Header length is always 12 */
- if (data[0] != 12 || len < 12) {
- PDEBUG(D_PACK, "bad header");
- goto discard;
- }
-
- /* Check errors */
- if (data[1] & UVC_STREAM_ERR) {
- PDEBUG(D_PACK, "payload error");
- goto discard;
- }
-
- /* Extract PTS and FID */
- if (!(data[1] & UVC_STREAM_PTS)) {
- PDEBUG(D_PACK, "PTS not present");
- goto discard;
- }
- this_pts = (data[5] << 24) | (data[4] << 16) | (data[3] << 8) | data[2];
- this_fid = (data[1] & UVC_STREAM_FID) ? 1 : 0;
-
- /* If PTS or FID has changed, start a new frame. */
- if (this_pts != sd->last_pts || this_fid != sd->last_fid) {
- gspca_frame_add(gspca_dev, FIRST_PACKET, frame, NULL, 0);
- sd->last_pts = this_pts;
- sd->last_fid = this_fid;
- }
-
- /* Add the data from this payload */
- gspca_frame_add(gspca_dev, INTER_PACKET, frame,
- data + 12, len - 12);
-
- /* If this packet is marked as EOF, end the frame */
- if (data[1] & UVC_STREAM_EOF) {
- sd->last_pts = 0;
-
- if ((frame->data_end - frame->data) !=
- (gspca_dev->width * gspca_dev->height * 2)) {
- PDEBUG(D_PACK, "short frame");
+ /* Verify UVC header. Header length is always 12 */
+ if (data[0] != 12 || len < 12) {
+ PDEBUG(D_PACK, "bad header");
goto discard;
}
- frame = gspca_frame_add(gspca_dev, LAST_PACKET, frame,
- NULL, 0);
+ /* Check errors */
+ if (data[1] & UVC_STREAM_ERR) {
+ PDEBUG(D_PACK, "payload error");
+ goto discard;
}
- /* Done this payload */
- goto scan_next;
+ /* Extract PTS and FID */
+ if (!(data[1] & UVC_STREAM_PTS)) {
+ PDEBUG(D_PACK, "PTS not present");
+ goto discard;
+ }
+ this_pts = (data[5] << 24) | (data[4] << 16)
+ | (data[3] << 8) | data[2];
+ this_fid = (data[1] & UVC_STREAM_FID) ? 1 : 0;
+
+ /* If PTS or FID has changed, start a new frame. */
+ if (this_pts != sd->last_pts || this_fid != sd->last_fid) {
+ gspca_frame_add(gspca_dev, FIRST_PACKET, frame,
+ NULL, 0);
+ sd->last_pts = this_pts;
+ sd->last_fid = this_fid;
+ }
+
+ /* Add the data from this payload */
+ gspca_frame_add(gspca_dev, INTER_PACKET, frame,
+ data + 12, len - 12);
+
+ /* If this packet is marked as EOF, end the frame */
+ if (data[1] & UVC_STREAM_EOF) {
+ sd->last_pts = 0;
+
+ if (frame->data_end - frame->data !=
+ gspca_dev->width * gspca_dev->height * 2) {
+ PDEBUG(D_PACK, "short frame");
+ goto discard;
+ }
+
+ frame = gspca_frame_add(gspca_dev, LAST_PACKET, frame,
+ NULL, 0);
+ }
+
+ /* Done this payload */
+ goto scan_next;
discard:
- /* Discard data until a new frame starts. */
- gspca_frame_add(gspca_dev, DISCARD_PACKET, frame, NULL, 0);
- goto scan_next;
+ /* Discard data until a new frame starts. */
+ gspca_frame_add(gspca_dev, DISCARD_PACKET, frame, NULL, 0);
+
+scan_next:
+ remaining_len -= len;
+ data += len;
+ } while (remaining_len > 0);
}
/* get stream parameters (framerate) */