From eceb3f26f407d65dae3902180b3c9f3128f0f349 Mon Sep 17 00:00:00 2001
From: Stephen Warren <swarren@nvidia.com>
Date: Tue, 22 Apr 2014 14:37:53 -0600
Subject: [PATCH] ARM: tegra: add GPIO initialization table function

The HW-defined procedure for booting Tegra requires that some pins be
set up as GPIOs immediately at boot in order to avoid glitches on those
pins, when the pinmux is programmed. Add a feature to the GPIO driver
which executes a GPIO configuration table. Board files will use this to
implement the correct HW initialization procedure.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
---
 arch/arm/include/asm/arch-tegra/gpio.h | 20 ++++++++++++++++++++
 drivers/gpio/tegra_gpio.c              | 20 ++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/arch/arm/include/asm/arch-tegra/gpio.h b/arch/arm/include/asm/arch-tegra/gpio.h
index d97190dd7c..44cd455699 100644
--- a/arch/arm/include/asm/arch-tegra/gpio.h
+++ b/arch/arm/include/asm/arch-tegra/gpio.h
@@ -14,11 +14,31 @@
 #define GPIO_FULLPORT(x)	((x) >> 3)
 #define GPIO_BIT(x)		((x) & 0x7)
 
+enum tegra_gpio_init {
+	TEGRA_GPIO_INIT_IN,
+	TEGRA_GPIO_INIT_OUT0,
+	TEGRA_GPIO_INIT_OUT1,
+};
+
+struct tegra_gpio_config {
+	u32 gpio:16;
+	u32 init:2;
+};
+
 /*
  * Tegra-specific GPIO API
  */
 
+/**
+ * Configure a list of GPIOs
+ *
+ * @param config	List of GPIO configurations
+ * @param len		Number of config items in list
+ */
+void gpio_config_table(const struct tegra_gpio_config *config, int len);
+
 void gpio_info(void);
 
 #define gpio_status()	gpio_info()
+
 #endif	/* TEGRA_GPIO_H_ */
diff --git a/drivers/gpio/tegra_gpio.c b/drivers/gpio/tegra_gpio.c
index 82b30d5ab6..fea9d17f8e 100644
--- a/drivers/gpio/tegra_gpio.c
+++ b/drivers/gpio/tegra_gpio.c
@@ -221,6 +221,26 @@ int gpio_set_value(unsigned gpio, int value)
 	return 0;
 }
 
+void gpio_config_table(const struct tegra_gpio_config *config, int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++) {
+		switch (config[i].init) {
+		case TEGRA_GPIO_INIT_IN:
+			gpio_direction_input(config[i].gpio);
+			break;
+		case TEGRA_GPIO_INIT_OUT0:
+			gpio_direction_output(config[i].gpio, 0);
+			break;
+		case TEGRA_GPIO_INIT_OUT1:
+			gpio_direction_output(config[i].gpio, 1);
+			break;
+		}
+		set_config(config[i].gpio, 1);
+	}
+}
+
 /*
  * Display Tegra GPIO information
  */
-- 
2.39.5