video: tegra: support output pin polarities setting

Add support for set up pin polarities in DC driver.

fixes bug 758356

Change-Id: Iff7026929d73e9cf232baeda1f9f0c8bbd60b66b
Reviewed-on: http://git-master/r/11674
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Tested-by: Bharat Nihalani <bnihalani@nvidia.com>

3 files changed, 102 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/include/mach/dc.h b/arch/arm/mach-tegra/include/mach/dc.h
index 77a9f15bc0bf..0bc75fb4499f 100644
--- a/arch/arm/mach-tegra/include/mach/dc.h
+++ b/arch/arm/mach-tegra/include/mach/dc.h
@@ -44,6 +44,23 @@ enum {
 	TEGRA_DC_OUT_HDMI,
 };
 
+struct tegra_dc_out_pin {
+	int     name;
+	int     pol;
+};
+
+enum {
+	TEGRA_DC_OUT_PIN_DATA_ENABLE,
+	TEGRA_DC_OUT_PIN_H_SYNC,
+	TEGRA_DC_OUT_PIN_V_SYNC,
+	TEGRA_DC_OUT_PIN_PIXEL_CLOCK,
+};
+
+enum {
+	TEGRA_DC_OUT_PIN_POL_LOW,
+	TEGRA_DC_OUT_PIN_POL_HIGH,
+};
+
 struct tegra_dc_out {
 	int			type;
 	unsigned		flags;
@@ -62,6 +79,9 @@ struct tegra_dc_out {
 	struct tegra_dc_mode	*modes;
 	int			n_modes;
 
+	struct tegra_dc_out_pin	*out_pins;
+	unsigned		n_out_pins;
+
 	int	(*enable)(void);
 	int	(*disable)(void);
 };
diff --git a/drivers/video/tegra/dc/dc.c b/drivers/video/tegra/dc/dc.c
index 3c3a4754b7dc..cfe962be62f3 100644
--- a/drivers/video/tegra/dc/dc.c
+++ b/drivers/video/tegra/dc/dc.c
@@ -780,6 +780,76 @@ int tegra_dc_set_mode(struct tegra_dc *dc, const struct tegra_dc_mode *mode)
 }
 EXPORT_SYMBOL(tegra_dc_set_mode);
 
+static void tegra_dc_set_out_pin_polars(struct tegra_dc *dc,
+				const struct tegra_dc_out_pin *pins,
+				const unsigned int n_pins)
+{
+	unsigned int i;
+
+	int name;
+	int pol;
+
+	u32 pol1, pol3;
+
+	u32 set1, unset1;
+	u32 set3, unset3;
+
+	set1 = set3 = unset1 = unset3 = 0;
+
+	for (i = 0; i < n_pins; i++) {
+		name = (pins + i)->name;
+		pol  = (pins + i)->pol;
+
+		/* set polarity by name */
+		switch (name) {
+		case TEGRA_DC_OUT_PIN_DATA_ENABLE:
+			if (pol == TEGRA_DC_OUT_PIN_POL_LOW)
+				set3 |= LSPI_OUTPUT_POLARITY_LOW;
+			else
+				unset3 |= LSPI_OUTPUT_POLARITY_LOW;
+			break;
+		case TEGRA_DC_OUT_PIN_H_SYNC:
+			if (pol == TEGRA_DC_OUT_PIN_POL_LOW)
+				set1 |= LHS_OUTPUT_POLARITY_LOW;
+			else
+				unset1 |= LHS_OUTPUT_POLARITY_LOW;
+			break;
+		case TEGRA_DC_OUT_PIN_V_SYNC:
+			if (pol == TEGRA_DC_OUT_PIN_POL_LOW)
+				set1 |= LVS_OUTPUT_POLARITY_LOW;
+			else
+				unset1 |= LVS_OUTPUT_POLARITY_LOW;
+			break;
+		case TEGRA_DC_OUT_PIN_PIXEL_CLOCK:
+			if (pol == TEGRA_DC_OUT_PIN_POL_LOW)
+				set1 |= LSC0_OUTPUT_POLARITY_LOW;
+			else
+				unset1 |= LSC0_OUTPUT_POLARITY_LOW;
+			break;
+		default:
+			printk("Invalid argument in function %s\n",
+			       __FUNCTION__);
+			break;
+		}
+	}
+
+	mutex_lock(&dc->lock);
+
+	pol1 = tegra_dc_readl(dc, DC_COM_PIN_OUTPUT_POLARITY1);
+	pol3 = tegra_dc_readl(dc, DC_COM_PIN_OUTPUT_POLARITY3);
+
+	pol1 |= set1;
+	pol1 &= ~unset1;
+
+	pol3 |= set3;
+	pol3 &= ~unset3;
+
+	tegra_dc_writel(dc, pol1, DC_COM_PIN_OUTPUT_POLARITY1);
+	tegra_dc_writel(dc, pol3, DC_COM_PIN_OUTPUT_POLARITY3);
+
+	mutex_unlock(&dc->lock);
+}
+
 static void tegra_dc_set_out(struct tegra_dc *dc, struct tegra_dc_out *out)
 {
 	dc->out = out;
@@ -975,6 +1045,10 @@ static bool _tegra_dc_enable(struct tegra_dc *dc)
 	if (dc->out_ops && dc->out_ops->enable)
 		dc->out_ops->enable(dc);
 
+	if (dc->out->out_pins)
+		tegra_dc_set_out_pin_polars(dc, dc->out->out_pins,
+					    dc->out->n_out_pins);
+
 	/* force a full blending update */
 	dc->blend.z[0] = -1;
 
diff --git a/drivers/video/tegra/dc/dc_reg.h b/drivers/video/tegra/dc/dc_reg.h
index f643ec9ec742..1911b0ed5ca6 100644
--- a/drivers/video/tegra/dc/dc_reg.h
+++ b/drivers/video/tegra/dc/dc_reg.h
@@ -108,9 +108,17 @@
 #define DC_COM_PIN_OUTPUT_ENABLE2		0x304
 #define DC_COM_PIN_OUTPUT_ENABLE3		0x305
 #define DC_COM_PIN_OUTPUT_POLARITY0		0x306
+
 #define DC_COM_PIN_OUTPUT_POLARITY1		0x307
+#define  LHS_OUTPUT_POLARITY_LOW	(1 << 30)
+#define  LVS_OUTPUT_POLARITY_LOW	(1 << 28)
+#define  LSC0_OUTPUT_POLARITY_LOW	(1 << 24)
+
 #define DC_COM_PIN_OUTPUT_POLARITY2		0x308
+
 #define DC_COM_PIN_OUTPUT_POLARITY3		0x309
+#define  LSPI_OUTPUT_POLARITY_LOW	(1 << 8)
+
 #define DC_COM_PIN_OUTPUT_DATA0			0x30a
 #define DC_COM_PIN_OUTPUT_DATA1			0x30b
 #define DC_COM_PIN_OUTPUT_DATA2			0x30c