1 files changed, 33 insertions, 21 deletions

diff --git a/drivers/media/video/gspca/pac7311.c b/drivers/media/video/gspca/pac7311.c
index ea3d7021f401..815bea6edc44 100644
--- a/drivers/media/video/gspca/pac7311.c
+++ b/drivers/media/video/gspca/pac7311.c
@@ -31,7 +31,9 @@ MODULE_LICENSE("GPL");
 struct sd {
         struct gspca_dev gspca_dev;             /* !! must be the first item */
 
-        int avg_lum;
+        int lum_sum;
+        atomic_t avg_lum;
+        atomic_t do_gain;
 
         unsigned char brightness;
         unsigned char contrast;
@@ -271,6 +273,7 @@ static int sd_config(struct gspca_dev *gspca_dev,
         sd->contrast = CONTRAST_DEF;
         sd->colors = COLOR_DEF;
         sd->autogain = AUTOGAIN_DEF;
+        sd->ag_cnt = -1;
         return 0;
 }
 
@@ -311,6 +314,18 @@ static void setcolors(struct gspca_dev *gspca_dev)
         PDEBUG(D_CONF|D_STREAM, "color: %i", sd->colors);
 }
 
+static void setautogain(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        if (sd->autogain) {
+                sd->lum_sum = 0;
+                sd->ag_cnt = AG_CNT_START;
+        } else {
+                sd->ag_cnt = -1;
+        }
+}
+
 /* this function is called at open time */
 static int sd_open(struct gspca_dev *gspca_dev)
 {
@@ -320,8 +335,6 @@ static int sd_open(struct gspca_dev *gspca_dev)
 
 static void sd_start(struct gspca_dev *gspca_dev)
 {
-        struct sd *sd = (struct sd *) gspca_dev;
-
         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);
@@ -394,6 +407,7 @@ static void sd_start(struct gspca_dev *gspca_dev)
         setcontrast(gspca_dev);
         setbrightness(gspca_dev);
         setcolors(gspca_dev);
+        setautogain(gspca_dev);
 
         /* set correct resolution */
         switch (gspca_dev->cam.cam_mode[(int) gspca_dev->curr_mode].priv) {
@@ -431,13 +445,6 @@ static void sd_start(struct gspca_dev *gspca_dev)
         reg_w(gspca_dev, 0xff, 0x01);
         reg_w(gspca_dev, 0x78, 0x04);
         reg_w(gspca_dev, 0x78, 0x05);
-
-        if (sd->autogain) {
-                sd->ag_cnt = AG_CNT_START;
-                sd->avg_lum = 0;
-        } else {
-                sd->ag_cnt = -1;
-        }
 }
 
 static void sd_stopN(struct gspca_dev *gspca_dev)
@@ -473,13 +480,20 @@ static void sd_close(struct gspca_dev *gspca_dev)
         reg_w(gspca_dev, 0x78, 0x44); /* Bit_0=start stream, Bit_7=LED */
 }
 
-static void setautogain(struct gspca_dev *gspca_dev, int luma)
+static void do_autogain(struct gspca_dev *gspca_dev)
 {
+        struct sd *sd = (struct sd *) gspca_dev;
+        int luma;
         int luma_mean = 128;
         int luma_delta = 20;
         __u8 spring = 5;
         int Gbright;
 
+        if (!atomic_read(&sd->do_gain))
+                return;
+        atomic_set(&sd->do_gain, 0);
+
+        luma = atomic_read(&sd->avg_lum);
         Gbright = reg_r(gspca_dev, 0x02);
         PDEBUG(D_FRAM, "luma mean %d", luma);
         if (luma < luma_mean - luma_delta ||
@@ -523,12 +537,13 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev,
 
                         /* start of frame */
                         if (sd->ag_cnt >= 0 && p > 28) {
-                                sd->avg_lum += data[p - 23];
+                                sd->lum_sum += data[p - 23];
                                 if (--sd->ag_cnt < 0) {
                                         sd->ag_cnt = AG_CNT_START;
-                                        setautogain(gspca_dev,
-                                                sd->avg_lum / AG_CNT_START);
-                                        sd->avg_lum = 0;
+                                        atomic_set(&sd->avg_lum,
+                                                sd->lum_sum / AG_CNT_START);
+                                        sd->lum_sum = 0;
+                                        atomic_set(&sd->do_gain, 1);
                                 }
                         }
 
@@ -677,12 +692,8 @@ static int sd_setautogain(struct gspca_dev *gspca_dev, __s32 val)
         struct sd *sd = (struct sd *) gspca_dev;
 
         sd->autogain = val;
-        if (val) {
-                sd->ag_cnt = AG_CNT_START;
-                sd->avg_lum = 0;
-        } else {
-                sd->ag_cnt = -1;
-        }
+        if (gspca_dev->streaming)
+                setautogain(gspca_dev);
         return 0;
 }
 
@@ -706,6 +717,7 @@ static struct sd_desc sd_desc = {
         .stop0 = sd_stop0,
         .close = sd_close,
         .pkt_scan = sd_pkt_scan,
+        .dq_callback = do_autogain,
 };
 
 /* -- module initialisation -- */