[media] v4l2: make vidioc_s_jpegcomp const

Write-only ioctls should have a const argument in the ioctl op.
Do this conversion for vidioc_s_jpegcomp.
Adding const for write-only ioctls was decided during the 2012 Media Workshop.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/pci/zoran/zoran_driver.c

@@ -2674,7 +2674,7 @@ static int zoran_g_jpegcomp(struct file *file, void *__fh,
 }
 
 static int zoran_s_jpegcomp(struct file *file, void *__fh,
-					struct v4l2_jpegcompression *params)
+					const struct v4l2_jpegcompression *params)
 {
 	struct zoran_fh *fh = __fh;
 	struct zoran *zr = fh->zr;
@@ -2701,7 +2701,7 @@ static int zoran_s_jpegcomp(struct file *file, void *__fh,
 	if (!fh->buffers.allocated)
 		fh->buffers.buffer_size =
 			zoran_v4l2_calc_bufsize(&fh->jpg_settings);
-	fh->jpg_settings.jpg_comp = *params = settings.jpg_comp;
+	fh->jpg_settings.jpg_comp = settings.jpg_comp;
 sjpegc_unlock_and_return:
 	mutex_unlock(&zr->resource_lock);
 

drivers/media/usb/cpia2/cpia2_v4l.c

@@ -734,7 +734,8 @@ static int cpia2_g_jpegcomp(struct file *file, void *fh, struct v4l2_jpegcompres
  *
  *****************************************************************************/
 
-static int cpia2_s_jpegcomp(struct file *file, void *fh, struct v4l2_jpegcompression *parms)
+static int cpia2_s_jpegcomp(struct file *file, void *fh,
+		const struct v4l2_jpegcompression *parms)
 {
 	struct camera_data *cam = video_drvdata(file);
 
@@ -743,8 +744,6 @@ static int cpia2_s_jpegcomp(struct file *file, void *fh, struct v4l2_jpegcompres
 
 	cam->params.compression.inhibit_htables =
 		!(parms->jpeg_markers & V4L2_JPEG_MARKER_DHT);
-	parms->jpeg_markers &= V4L2_JPEG_MARKER_DQT | V4L2_JPEG_MARKER_DRI |
-			       V4L2_JPEG_MARKER_DHT;
 
 	if(parms->APP_len != 0) {
 		if(parms->APP_len > 0 &&

drivers/media/usb/gspca/gspca.c

@@ -1686,7 +1686,7 @@ static int vidioc_g_jpegcomp(struct file *file, void *priv,
 }
 
 static int vidioc_s_jpegcomp(struct file *file, void *priv,
-			struct v4l2_jpegcompression *jpegcomp)
+			const struct v4l2_jpegcompression *jpegcomp)
 {
 	struct gspca_dev *gspca_dev = video_drvdata(file);
 

drivers/media/usb/gspca/gspca.h

@@ -83,8 +83,10 @@ struct gspca_frame;
 typedef int (*cam_op) (struct gspca_dev *);
 typedef void (*cam_v_op) (struct gspca_dev *);
 typedef int (*cam_cf_op) (struct gspca_dev *, const struct usb_device_id *);
-typedef int (*cam_jpg_op) (struct gspca_dev *,
+typedef int (*cam_get_jpg_op) (struct gspca_dev *,
 				struct v4l2_jpegcompression *);
+typedef int (*cam_set_jpg_op) (struct gspca_dev *,
+				const struct v4l2_jpegcompression *);
 typedef int (*cam_reg_op) (struct gspca_dev *,
 				struct v4l2_dbg_register *);
 typedef int (*cam_ident_op) (struct gspca_dev *,
@@ -126,8 +128,8 @@ struct sd_desc {
 	cam_v_op stopN;		/* called on stream off - main alt */
 	cam_v_op stop0;		/* called on stream off & disconnect - alt 0 */
 	cam_v_op dq_callback;	/* called when a frame has been dequeued */
-	cam_jpg_op get_jcomp;
-	cam_jpg_op set_jcomp;
+	cam_get_jpg_op get_jcomp;
+	cam_set_jpg_op set_jcomp;
 	cam_qmnu_op querymenu;
 	cam_streamparm_op get_streamparm;
 	cam_streamparm_op set_streamparm;

drivers/media/usb/gspca/jeilinj.c

@@ -474,7 +474,7 @@ static int sd_init_controls(struct gspca_dev *gspca_dev)
 }
 
 static int sd_set_jcomp(struct gspca_dev *gspca_dev,
-			struct v4l2_jpegcompression *jcomp)
+			const struct v4l2_jpegcompression *jcomp)
 {
 	struct sd *sd = (struct sd *) gspca_dev;
 

drivers/media/usb/gspca/ov519.c

@@ -4762,7 +4762,7 @@ static int sd_get_jcomp(struct gspca_dev *gspca_dev,
 }
 
 static int sd_set_jcomp(struct gspca_dev *gspca_dev,
-			struct v4l2_jpegcompression *jcomp)
+			const struct v4l2_jpegcompression *jcomp)
 {
 	struct sd *sd = (struct sd *) gspca_dev;
 

drivers/media/usb/gspca/topro.c

@@ -4806,7 +4806,7 @@ static void sd_set_streamparm(struct gspca_dev *gspca_dev,
 }
 
 static int sd_set_jcomp(struct gspca_dev *gspca_dev,
-			struct v4l2_jpegcompression *jcomp)
+			const struct v4l2_jpegcompression *jcomp)
 {
 	struct sd *sd = (struct sd *) gspca_dev;
 

drivers/media/usb/gspca/zc3xx.c

@@ -6883,16 +6883,11 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev,
 }
 
 static int sd_set_jcomp(struct gspca_dev *gspca_dev,
-			struct v4l2_jpegcompression *jcomp)
+			const struct v4l2_jpegcompression *jcomp)
 {
 	struct sd *sd = (struct sd *) gspca_dev;
-	int ret;
 
-	ret = v4l2_ctrl_s_ctrl(sd->jpegqual, jcomp->quality);
-	if (ret)
-		return ret;
-	jcomp->quality = v4l2_ctrl_g_ctrl(sd->jpegqual);
-	return 0;
+	return v4l2_ctrl_s_ctrl(sd->jpegqual, jcomp->quality);
 }
 
 static int sd_get_jcomp(struct gspca_dev *gspca_dev,

drivers/media/usb/s2255/s2255drv.c

@@ -1556,7 +1556,7 @@ static int vidioc_g_jpegcomp(struct file *file, void *priv,
 }
 
 static int vidioc_s_jpegcomp(struct file *file, void *priv,
-			 struct v4l2_jpegcompression *jc)
+			 const struct v4l2_jpegcompression *jc)
 {
 	struct s2255_fh *fh = priv;
 	struct s2255_channel *channel = fh->channel;

drivers/staging/media/go7007/go7007-v4l2.c

@@ -1392,7 +1392,7 @@ static int vidioc_g_jpegcomp(struct file *file, void *priv,
 }
 
 static int vidioc_s_jpegcomp(struct file *file, void *priv,
-			 struct v4l2_jpegcompression *params)
+			 const struct v4l2_jpegcompression *params)
 {
 	if (params->quality != 50 ||
 			params->jpeg_markers != (V4L2_JPEG_MARKER_DHT |

include/media/v4l2-ioctl.h

@@ -195,7 +195,7 @@ struct v4l2_ioctl_ops {
 	int (*vidioc_g_jpegcomp)       (struct file *file, void *fh,
 					struct v4l2_jpegcompression *a);
 	int (*vidioc_s_jpegcomp)       (struct file *file, void *fh,
-					struct v4l2_jpegcompression *a);
+					const struct v4l2_jpegcompression *a);
 	int (*vidioc_g_enc_index)      (struct file *file, void *fh,
 					struct v4l2_enc_idx *a);
 	int (*vidioc_encoder_cmd)      (struct file *file, void *fh,