[U-Boot] [PATCH v3] i2c:gpio:s5p: I2C GPIO Software implementation (via soft_i2c)

Lukasz Majewski l.majewski at samsung.com
Wed Aug 10 11:21:35 CEST 2011 

This patch adds support for software I2C for GONI reference target.
It adds support for access to GPIOs by number, not as it is present,
by bank and offset.

Signed-off-by: Lukasz Majewski <l.majewski at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
Cc: Minkyu Kang <mk7.kang at samsung.com>
Cc: Heiko Schocher <hs at denx.de>

---
Changes for v2:
        - Generic GPIO code added to arch/arm/gpio.h
        - Platform dependent GPIO code added to board/samsung/goni.c
        - Code cleanup
Changes for v3:
        - I2C GPIO common code added to drivers/gpio/s5p_gpio.c
	- i2c_init_board() function added(required by soft_i2c)
---
 arch/arm/include/asm/arch-s5pc1xx/gpio.h |   38 ++++++++++++++++++++++++++++++
 board/samsung/goni/goni.c                |   16 ++++++++----
 drivers/gpio/s5p_gpio.c                  |   24 +++++++++++++++++++
 include/configs/s5p_goni.h               |   14 +++++++++++
 4 files changed, 86 insertions(+), 6 deletions(-)

diff --git a/arch/arm/include/asm/arch-s5pc1xx/gpio.h b/arch/arm/include/asm/arch-s5pc1xx/gpio.h
index 903de9c..619ba6f 100644
--- a/arch/arm/include/asm/arch-s5pc1xx/gpio.h
+++ b/arch/arm/include/asm/arch-s5pc1xx/gpio.h
@@ -134,6 +134,41 @@ unsigned int s5p_gpio_get_value(struct s5p_gpio_bank *bank, int gpio);
 void s5p_gpio_set_pull(struct s5p_gpio_bank *bank, int gpio, int mode);
 void s5p_gpio_set_drv(struct s5p_gpio_bank *bank, int gpio, int mode);
 void s5p_gpio_set_rate(struct s5p_gpio_bank *bank, int gpio, int mode);
+struct s5p_gpio_bank *s5p_gpio_get_bank(int nr);
+int s5p_gpio_get_pin(int nr);
+
+static inline int gpio_request(int gpio, const char *label)
+{
+       return 0;
+}
+
+static inline int gpio_direction_input(int nr)
+{
+       s5p_gpio_direction_input(s5p_gpio_get_bank(nr),
+				s5p_gpio_get_pin(nr));
+       return 0;
+}
+
+static inline int gpio_direction_output(int nr, int value)
+{
+       s5p_gpio_direction_output(s5p_gpio_get_bank(nr),
+				 s5p_gpio_get_pin(nr), value);
+       return 0;
+}
+
+static inline int gpio_get_value(int nr)
+{
+       return (int) s5p_gpio_get_value(s5p_gpio_get_bank(nr),
+				       s5p_gpio_get_pin(nr));
+}
+
+static inline void gpio_set_value(int nr, int value)
+{
+       s5p_gpio_set_value(s5p_gpio_get_bank(nr),
+			  s5p_gpio_get_pin(nr), value);
+}
+
+extern struct s5pc110_gpio *s5p_gpio;
 #endif
 
 /* Pin configurations */
@@ -155,4 +190,7 @@ void s5p_gpio_set_rate(struct s5p_gpio_bank *bank, int gpio, int mode);
 #define GPIO_DRV_FAST	0x0
 #define GPIO_DRV_SLOW	0x1
 
+/* GPIO pins per bank  */
+#define GPIO_PER_BANK 8
+
 #endif
diff --git a/board/samsung/goni/goni.c b/board/samsung/goni/goni.c
index e24cd29..354f5ad 100644
--- a/board/samsung/goni/goni.c
+++ b/board/samsung/goni/goni.c
@@ -28,12 +28,12 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-static struct s5pc110_gpio *s5pc110_gpio;
+struct s5pc110_gpio *s5p_gpio;
 
 int board_init(void)
 {
 	/* Set Initial global variables */
-	s5pc110_gpio = (struct s5pc110_gpio *)S5PC110_GPIO_BASE;
+	s5p_gpio = (struct s5pc110_gpio *)S5PC110_GPIO_BASE;
 
 	gd->bd->bi_arch_number = MACH_TYPE_GONI;
 	gd->bd->bi_boot_params = PHYS_SDRAM_1 + 0x100;
@@ -67,13 +67,17 @@ int checkboard(void)
 }
 #endif
 
+#ifdef CONFIG_SOFT_I2C
+void i2c_init_board(void) {}
+#endif
+
 #ifdef CONFIG_GENERIC_MMC
 int board_mmc_init(bd_t *bis)
 {
 	int i;
 
 	/* MASSMEMORY_EN: XMSMDATA7: GPJ2[7] output high */
-	s5p_gpio_direction_output(&s5pc110_gpio->j2, 7, 1);
+	s5p_gpio_direction_output(&s5p_gpio->j2, 7, 1);
 
 	/*
 	 * MMC0 GPIO
@@ -86,11 +90,11 @@ int board_mmc_init(bd_t *bis)
 		if (i == 2)
 			continue;
 		/* GPG0[0:6] special function 2 */
-		s5p_gpio_cfg_pin(&s5pc110_gpio->g0, i, 0x2);
+		s5p_gpio_cfg_pin(&s5p_gpio->g0, i, 0x2);
 		/* GPG0[0:6] pull disable */
-		s5p_gpio_set_pull(&s5pc110_gpio->g0, i, GPIO_PULL_NONE);
+		s5p_gpio_set_pull(&s5p_gpio->g0, i, GPIO_PULL_NONE);
 		/* GPG0[0:6] drv 4x */
-		s5p_gpio_set_drv(&s5pc110_gpio->g0, i, GPIO_DRV_4X);
+		s5p_gpio_set_drv(&s5p_gpio->g0, i, GPIO_DRV_4X);
 	}
 
 	return s5p_mmc_init(0, 4);
diff --git a/drivers/gpio/s5p_gpio.c b/drivers/gpio/s5p_gpio.c
index 2043859..e247b6f 100644
--- a/drivers/gpio/s5p_gpio.c
+++ b/drivers/gpio/s5p_gpio.c
@@ -141,3 +141,27 @@ void s5p_gpio_set_rate(struct s5p_gpio_bank *bank, int gpio, int mode)
 
 	writel(value, &bank->drv);
 }
+
+#ifdef CONFIG_SOFT_I2C
+/* Platform dependent functions for extracting GPIO number */
+int s5p_gpio_get_nr(void *gp_ptr, int gpio)
+{
+	unsigned int offset = gp_ptr - (void *) s5p_gpio;
+	offset /= sizeof(struct s5p_gpio_bank);
+
+	return (offset * GPIO_PER_BANK) + gpio;
+}
+
+struct s5p_gpio_bank *s5p_gpio_get_bank(int nr)
+{
+	int bank = nr / GPIO_PER_BANK;
+	bank *= sizeof(struct s5p_gpio_bank);
+
+	return (struct s5p_gpio_bank *) ((void *) s5p_gpio + bank);
+}
+
+int s5p_gpio_get_pin(int nr)
+{
+	return nr % GPIO_PER_BANK;
+}
+#endif
diff --git a/include/configs/s5p_goni.h b/include/configs/s5p_goni.h
index 381bb39..620dca7 100644
--- a/include/configs/s5p_goni.h
+++ b/include/configs/s5p_goni.h
@@ -223,4 +223,18 @@
 
 #define CONFIG_SYS_INIT_SP_ADDR	(CONFIG_SYS_LOAD_ADDR - 0x1000000)
 
+#include <asm/arch/gpio.h>
+/*
+ * I2C Settings
+ */
+#define S5PC110_GPIO_J3          (S5PC110_GPIO_BASE + 0x2C0)
+#define CONFIG_SOFT_I2C_GPIO_SCL s5p_gpio_get_nr(S5PC110_GPIO_J3, 3)
+#define CONFIG_SOFT_I2C_GPIO_SDA s5p_gpio_get_nr(S5PC110_GPIO_J3, 0)
+
+#define CONFIG_SOFT_I2C	1
+#define CONFIG_SYS_I2C_SPEED	50000
+#define CONFIG_SYS_I2C_INIT_BOARD
+#define CONFIG_I2C_MULTI_BUS
+#define CONFIG_SYS_MAX_I2C_BUS	7
+
 #endif	/* __CONFIG_H */
-- 
1.7.2.3

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