drm/omap: HDMI: support double-pixel pixel clock

We need double-pixel mode (pixel repetition) for interlace modes. This
patch adds the necessary support to HDMI to double the pixel clock when
double-pixel mode is used.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi5.c b/drivers/gpu/drm/omapdrm/dss/hdmi5.c
index 4485a1c..34174ea 100644
--- a/drivers/gpu/drm/omapdrm/dss/hdmi5.c
+++ b/drivers/gpu/drm/omapdrm/dss/hdmi5.c
@@ -184,6 +184,7 @@
 	struct omap_video_timings *p;
 	struct omap_overlay_manager *mgr = hdmi.output.manager;
 	struct dss_pll_clock_info hdmi_cinfo = { 0 };
+	unsigned pc;
 
 	r = hdmi_power_on_core(dssdev);
 	if (r)
@@ -193,7 +194,11 @@
 
 	DSSDBG("hdmi_power_on x_res= %d y_res = %d\n", p->x_res, p->y_res);
 
-	hdmi_pll_compute(&hdmi.pll, p->pixelclock, &hdmi_cinfo);
+	pc = p->pixelclock;
+	if (p->double_pixel)
+		pc *= 2;
+
+	hdmi_pll_compute(&hdmi.pll, pc, &hdmi_cinfo);
 
 	/* disable and clear irqs */
 	hdmi_wp_clear_irqenable(&hdmi.wp, 0xffffffff);