[media] V4L: mt9m111: fix pixel clock

This camera driver supports only rising edge, which is the default
setting of the device. The function mt9m111_setup_pixfmt() overwrites
this setting. So the driver actually uses falling edge.
This patch corrects that.
Signed-off-by: Teresa Gámez <t.gamez@phytec.de>
[g.liakhovetski@gmx.de: removed superfluous register write]
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Tested-by: Teresa Gámez <t.gamez@phytec.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/mt9m111.c

@@ -315,10 +315,20 @@ static int mt9m111_setup_rect(struct i2c_client *client,
 static int mt9m111_setup_pixfmt(struct i2c_client *client, u16 outfmt)
 {
 	int ret;
+	u16 mask = MT9M111_OUTFMT_PROCESSED_BAYER | MT9M111_OUTFMT_RGB |
+		MT9M111_OUTFMT_BYPASS_IFP | MT9M111_OUTFMT_SWAP_RGB_EVEN |
+		MT9M111_OUTFMT_RGB565 | MT9M111_OUTFMT_RGB555 |
+		MT9M111_OUTFMT_SWAP_YCbCr_Cb_Cr |
+		MT9M111_OUTFMT_SWAP_YCbCr_C_Y;
 
-	ret = reg_write(OUTPUT_FORMAT_CTRL2_A, outfmt);
+	ret = reg_read(OUTPUT_FORMAT_CTRL2_A);
+	if (ret >= 0)
+		ret = reg_write(OUTPUT_FORMAT_CTRL2_A, (ret & ~mask) | outfmt);
 	if (!ret)
-		ret = reg_write(OUTPUT_FORMAT_CTRL2_B, outfmt);
+		ret = reg_read(OUTPUT_FORMAT_CTRL2_B);
+	if (ret >= 0)
+		ret = reg_write(OUTPUT_FORMAT_CTRL2_B, (ret & ~mask) | outfmt);
+
 	return ret;
 }