[media] s5p-jpeg: Ensure setting correct value of the chroma subsampling control
authorJacek Anaszewski <j.anaszewski@samsung.com>
Thu, 21 Nov 2013 16:34:01 +0000 (13:34 -0300)
committerMauro Carvalho Chehab <m.chehab@samsung.com>
Wed, 18 Dec 2013 13:50:24 +0000 (11:50 -0200)
Exynos4x12 has limitations regarding setting chroma subsampling
of an output JPEG image. It cannot be lower than the subsampling
of the raw source image. Also in case of V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY
option the source image fourcc has to be V4L2_PIX_FMT_GREY.
This patch implements try_ctrl callback containing mechanism that
prevents setting invalid value of the V4L2_CID_JPEG_CHROMA_SUBSAMPLING
control.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
drivers/media/platform/s5p-jpeg/jpeg-core.c

index ea9cf737201b6524b02697c42237e1fc63084b0c..3c06487918d56865416b3eb201ece0497e36f4d8 100644 (file)
@@ -1213,6 +1213,40 @@ static int s5p_jpeg_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
        return 0;
 }
 
+static int s5p_jpeg_try_ctrl(struct v4l2_ctrl *ctrl)
+{
+       struct s5p_jpeg_ctx *ctx = ctrl_to_ctx(ctrl);
+       unsigned long flags;
+       int ret = 0;
+
+       spin_lock_irqsave(&ctx->jpeg->slock, flags);
+
+       if (ctrl->id == V4L2_CID_JPEG_CHROMA_SUBSAMPLING) {
+               if (ctx->jpeg->variant->version == SJPEG_S5P)
+                       goto error_free;
+               /*
+                * The exynos4x12 device requires input raw image fourcc
+                * to be V4L2_PIX_FMT_GREY if gray jpeg format
+                * is to be set.
+                */
+               if (ctx->out_q.fmt->fourcc != V4L2_PIX_FMT_GREY &&
+                   ctrl->val == V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY) {
+                       ret = -EINVAL;
+                       goto error_free;
+               }
+               /*
+                * The exynos4x12 device requires resulting jpeg subsampling
+                * not to be lower than the input raw image subsampling.
+                */
+               if (ctx->out_q.fmt->subsampling > ctrl->val)
+                       ctrl->val = ctx->out_q.fmt->subsampling;
+       }
+
+error_free:
+       spin_unlock_irqrestore(&ctx->jpeg->slock, flags);
+       return ret;
+}
+
 static int s5p_jpeg_s_ctrl(struct v4l2_ctrl *ctrl)
 {
        struct s5p_jpeg_ctx *ctx = ctrl_to_ctx(ctrl);
@@ -1238,6 +1272,7 @@ static int s5p_jpeg_s_ctrl(struct v4l2_ctrl *ctrl)
 
 static const struct v4l2_ctrl_ops s5p_jpeg_ctrl_ops = {
        .g_volatile_ctrl        = s5p_jpeg_g_volatile_ctrl,
+       .try_ctrl               = s5p_jpeg_try_ctrl,
        .s_ctrl                 = s5p_jpeg_s_ctrl,
 };