OMAPDSS: DPI: Maintain our own timings field in driver data

The DPI driver currently relies on the timings in omap_dss_device struct to
configure the DISPC accordingly. This makes the DPI interface driver dependent
on the omap_dss_device struct.

Make the DPI driver data maintain it's own timings field. The panel driver is
expected to call dpi_set_timings()(renamed to omapdss_dpi_set_timings) to set
these timings before the panel is enabled.

In the set_timings() op, we still ensure that the omap_dss_device timings
(dssdev->panel.timings) are configured. This will later be configured only by
the DPI panel drivers.

Signed-off-by: Archit Taneja <archit@ti.com>

drivers/video/omap2/displays/panel-picodlp.c

@@ -377,6 +377,9 @@ static int picodlp_panel_power_on(struct omap_dss_device *dssdev)
 	 * then only i2c commands can be successfully sent to dpp2600
 	 */
 	msleep(1000);
+
+	omapdss_dpi_set_timings(dssdev, &dssdev->panel.timings);
+
 	r = omapdss_dpi_display_enable(dssdev);
 	if (r) {
 		dev_err(&dssdev->dev, "failed to enable DPI\n");