media: atomisp: Fix atomisp_try_fmt_cap() always returning YUV420 pixelformat

The atomisp_try_fmt() call in atomisp_try_fmt_cap() replaces
the pixelformat passed by userspace with the sensors native pixelformat.

Which always gets replaced by V4L2_PIX_FMT_YUV420 by atomisp_adjust_fmt()
because raw sensor formats are not supported.

This needs to be fixed so that userspace which does a try_fmt call before
s_fmt does not end up always getting YUV420 even if it passed something
else into the try_fmt call.

To fix this restore the userspace requested pixelformat before
the atomisp_adjust_fmt() call. atomisp_adjust_fmt() will replace this
with V4L2_PIX_FMT_YUV420 in case an unsupported format is requested.

Note this relies on the "media: atomisp: Refactor atomisp_adjust_fmt()"
change, before that atomisp_adjust_fmt() would return -EINVAL for
unsupported pixelformats.
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/staging/media/atomisp/pci/atomisp_ioctl.c

@@ -922,6 +922,7 @@ static int atomisp_try_fmt_cap(struct file *file, void *fh,
 			       struct v4l2_format *f)
 {
 	struct video_device *vdev = video_devdata(file);
+	u32 pixfmt = f->fmt.pix.pixelformat;
 	int ret;
 
 	/*
@@ -935,6 +936,12 @@ static int atomisp_try_fmt_cap(struct file *file, void *fh,
 	if (ret)
 		return ret;
 
+	/*
+	 * atomisp_try_fmt() replaces pixelformat with the sensors native
+	 * format, restore the actual format requested by userspace.
+	 */
+	f->fmt.pix.pixelformat = pixfmt;
+
 	return atomisp_adjust_fmt(f);
 }