V4L/DVB (9787): soc-camera: let camera host drivers decide upon pixel format

Pixel format requested by the user is not necessarily the same, as what
a sensor driver provides. There are situations, when a camera host driver
provides the required format, but requires a different format from the
sensor. Further, the list of formats, supported by sensors is pretty static
and can be pretty good described with a constant list of structures. Whereas
decisions, made by camera host drivers to support requested formats can be
quite complex, therefore it is better to let the host driver do the work.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/pxa_camera.c b/drivers/media/video/pxa_camera.c
index 2a811f8..a375872 100644
--- a/drivers/media/video/pxa_camera.c
+++ b/drivers/media/video/pxa_camera.c
@@ -907,17 +907,43 @@
 static int pxa_camera_set_fmt_cap(struct soc_camera_device *icd,
 				  __u32 pixfmt, struct v4l2_rect *rect)
 {
-	return icd->ops->set_fmt_cap(icd, pixfmt, rect);
+	const struct soc_camera_data_format *cam_fmt;
+	int ret;
+
+	/*
+	 * TODO: find a suitable supported by the SoC output format, check
+	 * whether the sensor supports one of acceptable input formats.
+	 */
+	if (pixfmt) {
+		cam_fmt = soc_camera_format_by_fourcc(icd, pixfmt);
+		if (!cam_fmt)
+			return -EINVAL;
+	}
+
+	ret = icd->ops->set_fmt_cap(icd, pixfmt, rect);
+	if (pixfmt && !ret)
+		icd->current_fmt = cam_fmt;
+
+	return ret;
 }
 
 static int pxa_camera_try_fmt_cap(struct soc_camera_device *icd,
 				  struct v4l2_format *f)
 {
+	const struct soc_camera_data_format *cam_fmt;
 	int ret = pxa_camera_try_bus_param(icd, f->fmt.pix.pixelformat);
 
 	if (ret < 0)
 		return ret;
 
+	/*
+	 * TODO: find a suitable supported by the SoC output format, check
+	 * whether the sensor supports one of acceptable input formats.
+	 */
+	cam_fmt = soc_camera_format_by_fourcc(icd, f->fmt.pix.pixelformat);
+	if (!cam_fmt)
+		return -EINVAL;
+
 	/* limit to pxa hardware capabilities */
 	if (f->fmt.pix.height < 32)
 		f->fmt.pix.height = 32;
@@ -929,6 +955,10 @@
 		f->fmt.pix.width = 2048;
 	f->fmt.pix.width &= ~0x01;
 
+	f->fmt.pix.bytesperline = f->fmt.pix.width *
+		DIV_ROUND_UP(cam_fmt->depth, 8);
+	f->fmt.pix.sizeimage = f->fmt.pix.height * f->fmt.pix.bytesperline;
+
 	/* limit to sensor capabilities */
 	return icd->ops->try_fmt_cap(icd, f);
 }