V4L/DVB (11040): gspca - most jpeg subdrivers: Have the JPEG quality settable.

The JPEG quality of the images (quantization tables) is now settable by the
VIDIOC_S_JPEGCOMP ioctl.

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

1 files changed, 34 insertions, 1 deletions

diff --git a/drivers/media/video/gspca/mars.c b/drivers/media/video/gspca/mars.c
index 6eb813e7b714..75e8d14e4ac7 100644
--- a/drivers/media/video/gspca/mars.c
+++ b/drivers/media/video/gspca/mars.c
@@ -37,6 +37,9 @@ struct sd {
         u8 gamma;
         u8 sharpness;
         u8 quality;
+#define QUALITY_MIN 40
+#define QUALITY_MAX 70
+#define QUALITY_DEF 50
 
         u8 *jpeg_hdr;
 };
@@ -178,7 +181,7 @@ static int sd_config(struct gspca_dev *gspca_dev,
         sd->colors = COLOR_DEF;
         sd->gamma = GAMMA_DEF;
         sd->sharpness = SHARPNESS_DEF;
-        sd->quality = 50;
+        sd->quality = QUALITY_DEF;
         gspca_dev->nbalt = 9;           /* use the altsetting 08 */
         return 0;
 }
@@ -445,6 +448,34 @@ static int sd_getsharpness(struct gspca_dev *gspca_dev, __s32 *val)
         return 0;
 }
 
+static int sd_set_jcomp(struct gspca_dev *gspca_dev,
+                        struct v4l2_jpegcompression *jcomp)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        if (jcomp->quality < QUALITY_MIN)
+                sd->quality = QUALITY_MIN;
+        else if (jcomp->quality > QUALITY_MAX)
+                sd->quality = QUALITY_MAX;
+        else
+                sd->quality = jcomp->quality;
+        if (gspca_dev->streaming)
+                jpeg_set_qual(sd->jpeg_hdr, sd->quality);
+        return 0;
+}
+
+static int sd_get_jcomp(struct gspca_dev *gspca_dev,
+                        struct v4l2_jpegcompression *jcomp)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        memset(jcomp, 0, sizeof *jcomp);
+        jcomp->quality = sd->quality;
+        jcomp->jpeg_markers = V4L2_JPEG_MARKER_DHT
+                        | V4L2_JPEG_MARKER_DQT;
+        return 0;
+}
+
 /* sub-driver description */
 static const struct sd_desc sd_desc = {
         .name = MODULE_NAME,
@@ -456,6 +487,8 @@ static const struct sd_desc sd_desc = {
         .stopN = sd_stopN,
         .stop0 = sd_stop0,
         .pkt_scan = sd_pkt_scan,
+        .get_jcomp = sd_get_jcomp,
+        .set_jcomp = sd_set_jcomp,
 };
 
 /* -- module initialisation -- */