media: cadence: csi2rx: Configure DPHY using link freq

Some platforms like TI's J721E can have the CSI2RX paired with an
external DPHY. Use the generic PHY framework to configure the DPHY with
the correct link frequency.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Tested-by: Julien Massot <julien.massot@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Co-developed-by: Jai Luthra <j-luthra@ti.com>
Signed-off-by: Jai Luthra <j-luthra@ti.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Author: Pratyush Yadav

drivers/media/platform/cadence/cdns-csi2rx.c

@@ -145,8 +145,32 @@ static void csi2rx_reset(struct csi2rx_priv *csi2rx)
 static int csi2rx_configure_ext_dphy(struct csi2rx_priv *csi2rx)
 {
 	union phy_configure_opts opts = { };
+	struct phy_configure_opts_mipi_dphy *cfg = &opts.mipi_dphy;
+	struct v4l2_subdev_format sd_fmt = {
+		.which	= V4L2_SUBDEV_FORMAT_ACTIVE,
+		.pad	= CSI2RX_PAD_SINK,
+	};
+	const struct csi2rx_fmt *fmt;
+	s64 link_freq;
 	int ret;
 
+	ret = v4l2_subdev_call_state_active(&csi2rx->subdev, pad, get_fmt,
+					    &sd_fmt);
+	if (ret < 0)
+		return ret;
+
+	fmt = csi2rx_get_fmt_by_code(sd_fmt.format.code);
+
+	link_freq = v4l2_get_link_freq(csi2rx->source_subdev->ctrl_handler,
+				       fmt->bpp, 2 * csi2rx->num_lanes);
+	if (link_freq < 0)
+		return link_freq;
+
+	ret = phy_mipi_dphy_get_default_config_for_hsclk(link_freq,
+							 csi2rx->num_lanes, cfg);
+	if (ret)
+		return ret;
+
 	ret = phy_power_on(csi2rx->dphy);
 	if (ret)
 		return ret;