From a9d2ae7014d9e66dde6dd4a344308449508e4a22 Mon Sep 17 00:00:00 2001 From: Rajeshwari Shinde Date: Wed, 26 Dec 2012 20:03:12 +0000 Subject: [PATCH] I2C: Driver changes for FDT support Functions added to get the I2C bus number and reset I2C bus using FDT node. Signed-off-by: Rajeshwari Shinde Acked-by: Simon Glass Acked-by: Heiko Schocher Signed-off-by: Minkyu Kang --- drivers/i2c/s3c24x0_i2c.c | 83 ++++++++++++++++++++++++++++++++++++++- drivers/i2c/s3c24x0_i2c.h | 8 ++++ include/i2c.h | 26 ++++++++++++ 3 files changed, 116 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c index 90d297a284..7ec01ec62f 100644 --- a/drivers/i2c/s3c24x0_i2c.c +++ b/drivers/i2c/s3c24x0_i2c.c @@ -27,9 +27,11 @@ */ #include +#include #if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) #include #include +#include #else #include #endif @@ -60,7 +62,14 @@ #define I2C_TIMEOUT 1 /* 1 second */ -static unsigned int g_current_bus; /* Stores Current I2C Bus */ +/* + * For SPL boot some boards need i2c before SDRAM is initialised so force + * variables to live in SRAM + */ +static unsigned int g_current_bus __attribute__((section(".data"))); +static struct s3c24x0_i2c_bus i2c_bus[CONFIG_MAX_I2C_NUM] + __attribute__((section(".data"))); +static int i2c_busses __attribute__((section(".data"))); #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) static int GetI2CSDA(void) @@ -512,4 +521,76 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) (i2c, I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer, len) != 0); } + +#ifdef CONFIG_OF_CONTROL +void board_i2c_init(const void *blob) +{ + int node_list[CONFIG_MAX_I2C_NUM]; + int count, i; + + count = fdtdec_find_aliases_for_id(blob, "i2c", + COMPAT_SAMSUNG_S3C2440_I2C, node_list, + CONFIG_MAX_I2C_NUM); + + for (i = 0; i < count; i++) { + struct s3c24x0_i2c_bus *bus; + int node = node_list[i]; + + if (node <= 0) + continue; + bus = &i2c_bus[i]; + bus->regs = (struct s3c24x0_i2c *) + fdtdec_get_addr(blob, node, "reg"); + bus->id = pinmux_decode_periph_id(blob, node); + bus->node = node; + bus->bus_num = i2c_busses++; + exynos_pinmux_config(bus->id, 0); + } +} + +static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx) +{ + if (bus_idx < i2c_busses) + return &i2c_bus[bus_idx]; + + debug("Undefined bus: %d\n", bus_idx); + return NULL; +} + +int i2c_get_bus_num_fdt(int node) +{ + int i; + + for (i = 0; i < i2c_busses; i++) { + if (node == i2c_bus[i].node) + return i; + } + + debug("%s: Can't find any matched I2C bus\n", __func__); + return -1; +} + +int i2c_reset_port_fdt(const void *blob, int node) +{ + struct s3c24x0_i2c_bus *i2c; + int bus; + + bus = i2c_get_bus_num_fdt(node); + if (bus < 0) { + debug("could not get bus for node %d\n", node); + return -1; + } + + i2c = get_bus(bus); + if (!i2c) { + debug("get_bus() failed for node node %d\n", node); + return -1; + } + + i2c_ch_init(i2c->regs, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); + + return 0; +} +#endif + #endif /* CONFIG_HARD_I2C */ diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h index 2dd4b06a23..1243bf1b14 100644 --- a/drivers/i2c/s3c24x0_i2c.h +++ b/drivers/i2c/s3c24x0_i2c.h @@ -30,4 +30,12 @@ struct s3c24x0_i2c { u32 iicds; u32 iiclc; }; + +struct s3c24x0_i2c_bus { + int node; /* device tree node */ + int bus_num; /* i2c bus number */ + struct s3c24x0_i2c *regs; + enum periph_id id; +}; + #endif /* _S3C24X0_I2C_H */ diff --git a/include/i2c.h b/include/i2c.h index 16f099d2ee..c60d07583b 100644 --- a/include/i2c.h +++ b/include/i2c.h @@ -262,4 +262,30 @@ extern int get_multi_scl_pin(void); extern int get_multi_sda_pin(void); extern int multi_i2c_init(void); #endif + +/** + * Get FDT values for i2c bus. + * + * @param blob Device tree blbo + * @return the number of I2C bus + */ +void board_i2c_init(const void *blob); + +/** + * Find the I2C bus number by given a FDT I2C node. + * + * @param blob Device tree blbo + * @param node FDT I2C node to find + * @return the number of I2C bus (zero based), or -1 on error + */ +int i2c_get_bus_num_fdt(int node); + +/** + * Reset the I2C bus represented by the given a FDT I2C node. + * + * @param blob Device tree blbo + * @param node FDT I2C node to find + * @return 0 if port was reset, -1 if not found + */ +int i2c_reset_port_fdt(const void *blob, int node); #endif /* _I2C_H_ */ -- 2.25.1