V4L/DVB (8660): gspca: Simplify the scan of URB packets in pac7311.
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/gspca/pac7311.c b/drivers/media/video/gspca/pac7311.c
index 815bea6..caa3329 100644
--- a/drivers/media/video/gspca/pac7311.c
+++ b/drivers/media/video/gspca/pac7311.c
@@ -40,7 +40,8 @@
unsigned char colors;
unsigned char autogain;
- char ffseq;
+ char ffnb; /* number of 'ff' in the previous frame */
+ char tosof; /* number of bytes before next start of frame */
signed char ag_cnt;
#define AG_CNT_START 13
};
@@ -335,6 +336,10 @@
static void sd_start(struct gspca_dev *gspca_dev)
{
+ struct sd *sd = (struct sd *) gspca_dev;
+
+ sd->ffnb = 0;
+ sd->tosof = 0;
reg_w(gspca_dev, 0xff, 0x01);
reg_w_buf(gspca_dev, 0x0002, "\x48\x0a\x40\x08\x00\x00\x08\x00", 8);
reg_w_buf(gspca_dev, 0x000a, "\x06\xff\x11\xff\x5a\x30\x90\x4c", 8);
@@ -511,114 +516,123 @@
}
}
+/* output the jpeg header */
+static void put_jpeg_head(struct gspca_dev *gspca_dev,
+ struct gspca_frame *frame)
+{
+ unsigned char tmpbuf[4];
+
+ gspca_frame_add(gspca_dev, FIRST_PACKET, frame,
+ (__u8 *) pac7311_jpeg_header,
+ 12);
+ tmpbuf[0] = gspca_dev->height >> 8;
+ tmpbuf[1] = gspca_dev->height & 0xff;
+ tmpbuf[2] = gspca_dev->width >> 8;
+ tmpbuf[3] = gspca_dev->width & 0xff;
+ gspca_frame_add(gspca_dev, INTER_PACKET, frame,
+ tmpbuf, 4);
+ gspca_frame_add(gspca_dev, INTER_PACKET, frame,
+ (__u8 *) &pac7311_jpeg_header[16],
+ PAC7311_JPEG_HEADER_SIZE - 16);
+}
+
+/* this function is run at interrupt level */
static void sd_pkt_scan(struct gspca_dev *gspca_dev,
struct gspca_frame *frame, /* target */
__u8 *data, /* isoc packet */
int len) /* iso packet length */
{
struct sd *sd = (struct sd *) gspca_dev;
- unsigned char tmpbuf[4];
- int i, p, ffseq;
+ int i;
-/* if (len < 5) { */
- if (len < 6) {
-/* gspca_dev->last_packet_type = DISCARD_PACKET; */
- return;
+#define INTER_FRAME 0x53
+#define LUM_OFFSET 0x1e /* reverse offset / start of frame */
+
+ /*
+ * inside a frame, there may be:
+ * escaped ff ('ff 00')
+ * sequences'ff ff ff xx' to remove
+ * end of frame ('ff d9')
+ * at the end of frame, there are:
+ * ff d9 end of frame
+ * 0x33 bytes
+ * one byte luminosity
+ * 0x16 bytes
+ * ff ff 00 ff 96 62 44 start of frame header
+ */
+
+ if (sd->tosof == 0) { /* if inside a frame */
+
+ /* check for 'ff ff ff xx' at start and at end of packet */
+ /* (len is always >= 3) */
+ switch (sd->ffnb) {
+ case 1:
+ if (data[0] != 0xff)
+ break; /* keep 'ff 00' */
+ /* fall thru */
+ case 2:
+ case 3:
+ data += 4 - sd->ffnb;
+ len -= 4 - sd->ffnb;
+ sd->ffnb = 0;
+ break;
+ }
+ if (data[len - 1] == 0xff) {
+ if (data[len - 2] == 0xff) {
+ if (data[len - 3] == 0xff) {
+ sd->ffnb = 3;
+ len -= 3;
+ } else {
+ sd->ffnb = 2;
+ len -= 2;
+ }
+ } else {
+ sd->ffnb = 1;
+ len--;
+ }
+ }
+ } else { /* outside a frame */
+
+ /*
+ * get the luminosity
+ * and go to the start of frame
+ */
+ data += sd->tosof;
+ len -= sd->tosof;
+ if (sd->tosof > LUM_OFFSET)
+ sd->lum_sum += data[-LUM_OFFSET];
+ put_jpeg_head(gspca_dev, frame);
+ sd->tosof = 0;
}
- ffseq = sd->ffseq;
-
- for (p = 0; p < len - 6; p++) {
- if ((data[0 + p] == 0xff)
- && (data[1 + p] == 0xff)
- && (data[2 + p] == 0x00)
- && (data[3 + p] == 0xff)
- && (data[4 + p] == 0x96)) {
-
- /* start of frame */
- if (sd->ag_cnt >= 0 && p > 28) {
- sd->lum_sum += data[p - 23];
- if (--sd->ag_cnt < 0) {
- sd->ag_cnt = AG_CNT_START;
- atomic_set(&sd->avg_lum,
- sd->lum_sum / AG_CNT_START);
- sd->lum_sum = 0;
- atomic_set(&sd->do_gain, 1);
- }
+ for (i = 0; i < len; i++) {
+ if (data[i] != 0xff)
+ continue;
+ switch (data[i + 1]) {
+ case 0xd9: /* end of frame */
+ frame = gspca_frame_add(gspca_dev,
+ LAST_PACKET,
+ frame, data, i + 1);
+ data += INTER_FRAME;
+ len -= INTER_FRAME;
+ i = 0;
+ if (len > LUM_OFFSET)
+ sd->lum_sum += data[-LUM_OFFSET];
+ if (len < 0) {
+ sd->tosof = -len;
+ break;
}
-
- /* copy the end of data to the current frame */
- frame = gspca_frame_add(gspca_dev, LAST_PACKET, frame,
- data, p);
-
- /* put the JPEG header in the new frame */
- gspca_frame_add(gspca_dev, FIRST_PACKET, frame,
- (unsigned char *) pac7311_jpeg_header,
- 12);
- tmpbuf[0] = gspca_dev->height >> 8;
- tmpbuf[1] = gspca_dev->height & 0xff;
- tmpbuf[2] = gspca_dev->width >> 8;
- tmpbuf[3] = gspca_dev->width & 0xff;
- gspca_frame_add(gspca_dev, INTER_PACKET, frame,
- tmpbuf, 4);
- gspca_frame_add(gspca_dev, INTER_PACKET, frame,
- (unsigned char *) &pac7311_jpeg_header[16],
- PAC7311_JPEG_HEADER_SIZE - 16);
-
- data += p + 7;
- len -= p + 7;
- ffseq = 0;
+ put_jpeg_head(gspca_dev, frame);
+ break;
+ case 0xff: /* 'ff ff ff xx' */
+ gspca_frame_add(gspca_dev, INTER_PACKET,
+ frame, data, i);
+ data += i + 4;
+ len -= i + 4;
+ i = 0;
break;
}
}
-
- /* remove the 'ff ff ff xx' sequences */
- switch (ffseq) {
- case 3:
- data += 1;
- len -= 1;
- break;
- case 2:
- if (data[0] == 0xff) {
- data += 2;
- len -= 2;
- frame->data_end -= 2;
- }
- break;
- case 1:
- if (data[0] == 0xff
- && data[1] == 0xff) {
- data += 3;
- len -= 3;
- frame->data_end -= 1;
- }
- break;
- }
- for (i = 0; i < len - 4; i++) {
- if (data[i] == 0xff
- && data[i + 1] == 0xff
- && data[i + 2] == 0xff) {
- memmove(&data[i], &data[i + 4], len - i - 4);
- len -= 4;
- }
- }
- ffseq = 0;
- if (data[len - 4] == 0xff) {
- if (data[len - 3] == 0xff
- && data[len - 2] == 0xff) {
- len -= 4;
- }
- } else if (data[len - 3] == 0xff) {
- if (data[len - 2] == 0xff
- && data[len - 1] == 0xff)
- ffseq = 3;
- } else if (data[len - 2] == 0xff) {
- if (data[len - 1] == 0xff)
- ffseq = 2;
- } else if (data[len - 1] == 0xff)
- ffseq = 1;
- sd->ffseq = ffseq;
- gspca_frame_add(gspca_dev, INTER_PACKET, frame, data, len);
}
static void getbrightness(struct gspca_dev *gspca_dev)