[PATCH] saa6752hs: resolutions handling

This patch handles the VIDIOC_S_FMT and VIDIOC_G_FMT ioctls for the
saa6752hs.

As only 4 preset video formats are supported (SIF, 1/2D1, 2/3D1, D1), we
compute to which the asked resolution is the nearest and apply it.

Signed-off-by: Frederic Cand <frederic.cand@anevia.com>
Acked-by: Gerd Knorr <kraxel@bytesex.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 88 insertions, 1 deletions

diff --git a/drivers/media/video/saa7134/saa6752hs.c b/drivers/media/video/saa7134/saa6752hs.c
index cee13584c9cf..fe6abe34168c 100644
--- a/drivers/media/video/saa7134/saa6752hs.c
+++ b/drivers/media/video/saa7134/saa6752hs.c
@@ -32,9 +32,32 @@ MODULE_LICENSE("GPL");
 static struct i2c_driver driver;
 static struct i2c_client client_template;
 
+enum saa6752hs_videoformat {
+        SAA6752HS_VF_D1 = 0,    /* standard D1 video format: 720x576 */
+        SAA6752HS_VF_2_3_D1 = 1,/* 2/3D1 video format: 480x576 */
+        SAA6752HS_VF_1_2_D1 = 2,/* 1/2D1 video format: 352x576 */
+        SAA6752HS_VF_SIF = 3,   /* SIF video format: 352x288 */
+        SAA6752HS_VF_UNKNOWN,
+};
+
+static const struct v4l2_format v4l2_format_table[] =
+{
+        [SAA6752HS_VF_D1] = {
+                .fmt.pix.width = 720, .fmt.pix.height = 576 },
+        [SAA6752HS_VF_2_3_D1] = {
+                .fmt.pix.width = 480, .fmt.pix.height = 576 },
+        [SAA6752HS_VF_1_2_D1] = {
+                .fmt.pix.width = 352, .fmt.pix.height = 576 },
+        [SAA6752HS_VF_SIF] = {
+                .fmt.pix.width = 352, .fmt.pix.height = 288 },
+        [SAA6752HS_VF_UNKNOWN] = {
+                .fmt.pix.width = 0, .fmt.pix.height = 0},
+};
+
 struct saa6752hs_state {
         struct i2c_client             client;
         struct v4l2_mpeg_compression  params;
+        enum saa6752hs_videoformat    video_format;
 };
 
 enum saa6752hs_command {
@@ -256,6 +279,51 @@ static int saa6752hs_set_bitrate(struct i2c_client* client,
         return 0;
 }
 
+static void saa6752hs_set_subsampling(struct i2c_client* client,
+                                      struct v4l2_format* f)
+{
+        struct saa6752hs_state *h = i2c_get_clientdata(client);
+        int dist_352, dist_480, dist_720;
+
+        /*
+          FIXME: translate and round width/height into EMPRESS
+          subsample type:
+
+          type   |   PAL   |  NTSC
+          ---------------------------
+          SIF    | 352x288 | 352x240
+          1/2 D1 | 352x576 | 352x480
+          2/3 D1 | 480x576 | 480x480
+          D1     | 720x576 | 720x480
+        */
+
+        dist_352 = abs(f->fmt.pix.width - 352);
+        dist_480 = abs(f->fmt.pix.width - 480);
+        dist_720 = abs(f->fmt.pix.width - 720);
+        if (dist_720 < dist_480) {
+                f->fmt.pix.width = 720;
+                f->fmt.pix.height = 576;
+                h->video_format = SAA6752HS_VF_D1;
+        }
+        else if (dist_480 < dist_352) {
+                f->fmt.pix.width = 480;
+                f->fmt.pix.height = 576;
+                h->video_format = SAA6752HS_VF_2_3_D1;
+        }
+        else {
+                f->fmt.pix.width = 352;
+                if (abs(f->fmt.pix.height - 576) <
+                    abs(f->fmt.pix.height - 288)) {
+                        f->fmt.pix.height = 576;
+                        h->video_format = SAA6752HS_VF_1_2_D1;
+                }
+                else {
+                        f->fmt.pix.height = 288;
+                        h->video_format = SAA6752HS_VF_SIF;
+                }
+        }
+}
+
 
 static void saa6752hs_set_params(struct i2c_client* client,
                                  struct v4l2_mpeg_compression* params)
@@ -315,7 +383,7 @@ static int saa6752hs_init(struct i2c_client* client)
 
         // Set video format - must be done first as it resets other settings
         buf[0] = 0x41;
-        buf[1] = 0 /* MPEG_VIDEO_FORMAT_D1 */;
+        buf[1] = h->video_format;
         i2c_master_send(client, buf, 2);
 
         // set bitrate
@@ -494,6 +562,25 @@ saa6752hs_command(struct i2c_client *client, unsigned int cmd, void *arg)
         case VIDIOC_G_MPEGCOMP:
                 *params = h->params;
                 break;
+        case VIDIOC_G_FMT:
+        {
+           struct v4l2_format *f = arg;
+
+           if (h->video_format == SAA6752HS_VF_UNKNOWN)
+                   h->video_format = SAA6752HS_VF_D1;
+           f->fmt.pix.width =
+                   v4l2_format_table[h->video_format].fmt.pix.width;
+           f->fmt.pix.height =
+                   v4l2_format_table[h->video_format].fmt.pix.height;
+           break ;
+        }
+        case VIDIOC_S_FMT:
+        {
+                struct v4l2_format *f = arg;
+
+                saa6752hs_set_subsampling(client, f);
+                break;
+        }
         default:
                 /* nothing */
                 break;