V4L/DVB (8604): gspca: Fix of "scheduling while atomic" crash.

The crash is due to USB exchanges done at interrupt level.
These exchanges, tied to autogain, are now done by the application.
Also, there is a fix about autogain start.
Concerned subdrivers: etoms, pac7311, sonixj and spca561.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 72 insertions, 61 deletions

diff --git a/drivers/media/video/gspca/etoms.c b/drivers/media/video/gspca/etoms.c
index 6a4e68286ef4..1dbe92d01e6a 100644
--- a/drivers/media/video/gspca/etoms.c
+++ b/drivers/media/video/gspca/etoms.c
@@ -461,6 +461,52 @@ static void Et_init2(struct gspca_dev *gspca_dev)
         reg_w_val(gspca_dev, 0x80, 0x20);       /* 0x20; */
 }
 
+static void setbrightness(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+        int i;
+        __u8 brightness = sd->brightness;
+
+        for (i = 0; i < 4; i++)
+                reg_w_val(gspca_dev, ET_O_RED + i, brightness);
+}
+
+static void getbrightness(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+        int i;
+        int brightness = 0;
+
+        for (i = 0; i < 4; i++) {
+                reg_r(gspca_dev, ET_O_RED + i, 1);
+                brightness += gspca_dev->usb_buf[0];
+        }
+        sd->brightness = brightness >> 3;
+}
+
+static void setcontrast(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+        __u8 RGBG[] = { 0x80, 0x80, 0x80, 0x80, 0x00, 0x00 };
+        __u8 contrast = sd->contrast;
+
+        memset(RGBG, contrast, sizeof(RGBG) - 2);
+        reg_w(gspca_dev, ET_G_RED, RGBG, 6);
+}
+
+static void getcontrast(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+        int i;
+        int contrast = 0;
+
+        for (i = 0; i < 4; i++) {
+                reg_r(gspca_dev, ET_G_RED + i, 1);
+                contrast += gspca_dev->usb_buf[0];
+        }
+        sd->contrast = contrast >> 2;
+}
+
 static void setcolors(struct gspca_dev *gspca_dev)
 {
         struct sd *sd = (struct sd *) gspca_dev;
@@ -492,6 +538,16 @@ static void getcolors(struct gspca_dev *gspca_dev)
         }
 }
 
+static void setautogain(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        if (sd->autogain)
+                sd->ag_cnt = AG_CNT_START;
+        else
+                sd->ag_cnt = -1;
+}
+
 static void Et_init1(struct gspca_dev *gspca_dev)
 {
         __u8 value;
@@ -614,6 +670,7 @@ 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;
 }
 
@@ -641,6 +698,8 @@ static void sd_start(struct gspca_dev *gspca_dev)
         else
                 Et_init2(gspca_dev);
 
+        setautogain(gspca_dev);
+
         reg_w_val(gspca_dev, ET_RESET_ALL, 0x08);
         et_video(gspca_dev, 1);         /* video on */
 }
@@ -658,52 +717,6 @@ static void sd_close(struct gspca_dev *gspca_dev)
 {
 }
 
-static void setbrightness(struct gspca_dev *gspca_dev)
-{
-        struct sd *sd = (struct sd *) gspca_dev;
-        int i;
-        __u8 brightness = sd->brightness;
-
-        for (i = 0; i < 4; i++)
-                reg_w_val(gspca_dev, ET_O_RED + i, brightness);
-}
-
-static void getbrightness(struct gspca_dev *gspca_dev)
-{
-        struct sd *sd = (struct sd *) gspca_dev;
-        int i;
-        int brightness = 0;
-
-        for (i = 0; i < 4; i++) {
-                reg_r(gspca_dev, ET_O_RED + i, 1);
-                brightness += gspca_dev->usb_buf[0];
-        }
-        sd->brightness = brightness >> 3;
-}
-
-static void setcontrast(struct gspca_dev *gspca_dev)
-{
-        struct sd *sd = (struct sd *) gspca_dev;
-        __u8 RGBG[] = { 0x80, 0x80, 0x80, 0x80, 0x00, 0x00 };
-        __u8 contrast = sd->contrast;
-
-        memset(RGBG, contrast, sizeof(RGBG) - 2);
-        reg_w(gspca_dev, ET_G_RED, RGBG, 6);
-}
-
-static void getcontrast(struct gspca_dev *gspca_dev)
-{
-        struct sd *sd = (struct sd *) gspca_dev;
-        int i;
-        int contrast = 0;
-
-        for (i = 0; i < 4; i++) {
-                reg_r(gspca_dev, ET_G_RED + i, 1);
-                contrast += gspca_dev->usb_buf[0];
-        }
-        sd->contrast = contrast >> 2;
-}
-
 static __u8 Et_getgainG(struct gspca_dev *gspca_dev)
 {
         struct sd *sd = (struct sd *) gspca_dev;
@@ -733,15 +746,22 @@ static void Et_setgainG(struct gspca_dev *gspca_dev, __u8 gain)
 #define LIMIT(color) \
         (unsigned char)((color > 0xff)?0xff:((color < 0)?0:color))
 
-static void setautogain(struct gspca_dev *gspca_dev)
+static void do_autogain(struct gspca_dev *gspca_dev)
 {
-        __u8 luma = 0;
+        struct sd *sd = (struct sd *) gspca_dev;
+        __u8 luma;
         __u8 luma_mean = 128;
         __u8 luma_delta = 20;
         __u8 spring = 4;
-        int Gbright = 0;
+        int Gbright;
         __u8 r, g, b;
 
+        if (sd->ag_cnt < 0)
+                return;
+        if (--sd->ag_cnt >= 0)
+                return;
+        sd->ag_cnt = AG_CNT_START;
+
         Gbright = Et_getgainG(gspca_dev);
         reg_r(gspca_dev, ET_LUMA_CENTER, 4);
         g = (gspca_dev->usb_buf[0] + gspca_dev->usb_buf[3]) >> 1;
@@ -768,7 +788,6 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev,
                         __u8 *data,                     /* isoc packet */
                         int len)                        /* iso packet length */
 {
-        struct sd *sd;
         int seqframe;
 
         seqframe = data[0] & 0x3f;
@@ -783,13 +802,6 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev,
                 frame = gspca_frame_add(gspca_dev, LAST_PACKET, frame,
                                         data, 0);
                 gspca_frame_add(gspca_dev, FIRST_PACKET, frame, data, len);
-                sd = (struct sd *) gspca_dev;
-                if (sd->ag_cnt >= 0) {
-                        if (--sd->ag_cnt < 0) {
-                                sd->ag_cnt = AG_CNT_START;
-                                setautogain(gspca_dev);
-                        }
-                }
                 return;
         }
         if (len) {
@@ -862,10 +874,8 @@ 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;
-        else
-                sd->ag_cnt = -1;
+        if (gspca_dev->streaming)
+                setautogain(gspca_dev);
         return 0;
 }
 
@@ -889,6 +899,7 @@ static struct sd_desc sd_desc = {
         .stop0 = sd_stop0,
         .close = sd_close,
         .pkt_scan = sd_pkt_scan,
+        .dq_callback = do_autogain,
 };
 
 /* -- module initialisation -- */