[U-Boot] [PATCH 3/7] tegra: Add I2C support to funcmux

[Simon Glass <sjg@chromium.org>]

Add support to funcmux for selecting I2C functions and programming
the pinmux appropriately.

Signed-off-by: Simon Glass <sjg@chromium.org>
---
 arch/arm/cpu/armv7/tegra2/funcmux.c        |   75 +++++++++++++++++++++++-----
 arch/arm/include/asm/arch-tegra2/funcmux.h |    3 +
 2 files changed, 65 insertions(+), 13 deletions(-)

diff --git a/arch/arm/cpu/armv7/tegra2/funcmux.c b/arch/arm/cpu/armv7/tegra2/funcmux.c
index 0878f51..82d994a 100644
--- a/arch/arm/cpu/armv7/tegra2/funcmux.c
+++ b/arch/arm/cpu/armv7/tegra2/funcmux.c
@@ -26,27 +26,70 @@
 
 int funcmux_select(enum periph_id id, int config)
 {
-	if (config != 0) {
-		debug("%s: invalid config %d for periph_id %d", __func__,
-		      config, id);
-		return -1;
-	}
+	int bad_config = config != 0;
+
 	switch (id) {
 	case PERIPH_ID_UART1:
-		pinmux_set_func(PINGRP_IRRX, PMUX_FUNC_UARTA);
-		pinmux_set_func(PINGRP_IRTX, PMUX_FUNC_UARTA);
-		pinmux_tristate_disable(PINGRP_IRRX);
-		pinmux_tristate_disable(PINGRP_IRTX);
+		if (config == 0) {
+			pinmux_set_func(PINGRP_IRRX, PMUX_FUNC_UARTA);
+			pinmux_set_func(PINGRP_IRTX, PMUX_FUNC_UARTA);
+			pinmux_tristate_disable(PINGRP_IRRX);
+			pinmux_tristate_disable(PINGRP_IRTX);
+		}
 		break;
 
 	case PERIPH_ID_UART2:
-		pinmux_set_func(PINGRP_UAD, PMUX_FUNC_IRDA);
-		pinmux_tristate_disable(PINGRP_UAD);
+		if (config == 0) {
+			pinmux_set_func(PINGRP_UAD, PMUX_FUNC_IRDA);
+			pinmux_tristate_disable(PINGRP_UAD);
+		}
 		break;
 
 	case PERIPH_ID_UART4:
-		pinmux_set_func(PINGRP_GMC, PMUX_FUNC_UARTD);
-		pinmux_tristate_disable(PINGRP_GMC);
+		if (config == 0) {
+			pinmux_set_func(PINGRP_GMC, PMUX_FUNC_UARTD);
+			pinmux_tristate_disable(PINGRP_GMC);
+		}
+		break;
+
+	case PERIPH_ID_DVC_I2C:
+		/* there is only one selection, pinmux_config is ignored */
+		if (config == 0) {
+			pinmux_set_func(PINGRP_I2CP, PMUX_FUNC_I2C);
+			pinmux_tristate_disable(PINGRP_I2CP);
+		}
+		break;
+
+	case PERIPH_ID_I2C1:
+		/* support pinmux_config of 0 for now, */
+		if (config == 0) {
+			pinmux_set_func(PINGRP_RM, PMUX_FUNC_I2C);
+			pinmux_tristate_disable(PINGRP_RM);
+		}
+		break;
+	case PERIPH_ID_I2C2: /* I2C2 */
+		switch (config) {
+		case 0:	/* DDC pin group, select I2C2 */
+			pinmux_set_func(PINGRP_DDC, PMUX_FUNC_I2C2);
+			/* PTA to HDMI */
+			pinmux_set_func(PINGRP_PTA, PMUX_FUNC_HDMI);
+			pinmux_tristate_disable(PINGRP_DDC);
+			break;
+		case 1:	/* PTA pin group, select I2C2 */
+			pinmux_set_func(PINGRP_PTA, PMUX_FUNC_I2C2);
+			/* set DDC_SEL to RSVDx (RSVD2 works for now) */
+			pinmux_set_func(PINGRP_DDC, PMUX_FUNC_RSVD2);
+			pinmux_tristate_disable(PINGRP_PTA);
+			bad_config = 0;
+			break;
+		}
+		break;
+	case PERIPH_ID_I2C3: /* I2C3 */
+		/* support pinmux_config of 0 for now */
+		if (config == 0) {
+			pinmux_set_func(PINGRP_DTF, PMUX_FUNC_I2C3);
+			pinmux_tristate_disable(PINGRP_DTF);
+		}
 		break;
 
 	default:
@@ -54,5 +97,11 @@ int funcmux_select(enum periph_id id, int config)
 		return -1;
 	}
 
+	if (bad_config) {
+		debug("%s: invalid config %d for periph_id %d", __func__,
+		      config, id);
+		return -1;
+	}
+
 	return 0;
 }
diff --git a/arch/arm/include/asm/arch-tegra2/funcmux.h b/arch/arm/include/asm/arch-tegra2/funcmux.h
index 2d724a2..d4f9cfb 100644
--- a/arch/arm/include/asm/arch-tegra2/funcmux.h
+++ b/arch/arm/include/asm/arch-tegra2/funcmux.h
@@ -32,6 +32,9 @@
  * The basic config is 0, and higher numbers indicate different
  * pinmux settings to bring the peripheral out on other pins,
  *
+ * This function also disables tristate for the function's pins,
+ * so that they operate in normal mode.
+ *
  * @param id		Peripheral id
  * @param config	Configuration to use (generally 0)
  * @return 0 if ok, -1 on error (e.g. incorrect id or config)
-- 
1.7.3.1