From e406f9079b993f4d5d7b5a3452b11df81ff2aef0 Mon Sep 17 00:00:00 2001
From: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Date: Wed, 9 Jun 2010 15:28:12 +0300
Subject: [PATCH] OMAP: DSS2: DSI: Wait for DSI PLL clocks to be active before
 selecting them
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The TRM tells us to wait for the DSI PLL derived clocks to become
active before selecting them for use. I didn't actually have any issues
which this would fix but according to the TRM it seems to be the right
thing to do.

Signed-off-by: Ville Syrjälä <ville.syrjala@nokia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
---
 drivers/video/omap2/dss/dsi.c | 12 ++++++++++++
 drivers/video/omap2/dss/dss.c |  6 ++++++
 drivers/video/omap2/dss/dss.h |  8 ++++++++
 3 files changed, 26 insertions(+)

diff --git a/drivers/video/omap2/dss/dsi.c b/drivers/video/omap2/dss/dsi.c
index 04d84d13488b..6035904f1314 100644
--- a/drivers/video/omap2/dss/dsi.c
+++ b/drivers/video/omap2/dss/dsi.c
@@ -3195,6 +3195,18 @@ int dsi_init_display(struct omap_dss_device *dssdev)
 	return 0;
 }
 
+void dsi_wait_dsi1_pll_active(void)
+{
+	if (wait_for_bit_change(DSI_PLL_STATUS, 7, 1) != 1)
+		DSSERR("DSI1 PLL clock not active\n");
+}
+
+void dsi_wait_dsi2_pll_active(void)
+{
+	if (wait_for_bit_change(DSI_PLL_STATUS, 8, 1) != 1)
+		DSSERR("DSI2 PLL clock not active\n");
+}
+
 int dsi_init(struct platform_device *pdev)
 {
 	u32 rev;
diff --git a/drivers/video/omap2/dss/dss.c b/drivers/video/omap2/dss/dss.c
index 24b18258654f..77c3621c9171 100644
--- a/drivers/video/omap2/dss/dss.c
+++ b/drivers/video/omap2/dss/dss.c
@@ -265,6 +265,9 @@ void dss_select_dispc_clk_source(enum dss_clk_source clk_src)
 
 	b = clk_src == DSS_SRC_DSS1_ALWON_FCLK ? 0 : 1;
 
+	if (clk_src == DSS_SRC_DSI1_PLL_FCLK)
+		dsi_wait_dsi1_pll_active();
+
 	REG_FLD_MOD(DSS_CONTROL, b, 0, 0);	/* DISPC_CLK_SWITCH */
 
 	dss.dispc_clk_source = clk_src;
@@ -279,6 +282,9 @@ void dss_select_dsi_clk_source(enum dss_clk_source clk_src)
 
 	b = clk_src == DSS_SRC_DSS1_ALWON_FCLK ? 0 : 1;
 
+	if (clk_src == DSS_SRC_DSI2_PLL_FCLK)
+		dsi_wait_dsi2_pll_active();
+
 	REG_FLD_MOD(DSS_CONTROL, b, 1, 1);	/* DSI_CLK_SWITCH */
 
 	dss.dsi_clk_source = clk_src;
diff --git a/drivers/video/omap2/dss/dss.h b/drivers/video/omap2/dss/dss.h
index 786f433fd571..66e8e97d06a7 100644
--- a/drivers/video/omap2/dss/dss.h
+++ b/drivers/video/omap2/dss/dss.h
@@ -281,6 +281,8 @@ void dsi_pll_uninit(void);
 void dsi_get_overlay_fifo_thresholds(enum omap_plane plane,
 		u32 fifo_size, enum omap_burst_size *burst_size,
 		u32 *fifo_low, u32 *fifo_high);
+void dsi_wait_dsi1_pll_active(void);
+void dsi_wait_dsi2_pll_active(void);
 #else
 static inline int dsi_init(struct platform_device *pdev)
 {
@@ -289,6 +291,12 @@ static inline int dsi_init(struct platform_device *pdev)
 static inline void dsi_exit(void)
 {
 }
+static inline void dsi_wait_dsi1_pll_active(void)
+{
+}
+static inline void dsi_wait_dsi2_pll_active(void)
+{
+}
 #endif
 
 /* DPI */
-- 
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