diff options
| -rw-r--r-- | README | 10 | ||||
| -rw-r--r-- | drivers/i2c/soft_i2c.c | 52 |
2 files changed, 62 insertions, 0 deletions
@@ -1495,6 +1495,16 @@ The following options need to be configured: #define I2C_DELAY udelay(2) + CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA + + If your arch supports the generic GPIO framework (asm/gpio.h), + then you may alternatively define the two GPIOs that are to be + used as SCL / SDA. Any of the previous I2C_xxx macros will + have GPIO-based defaults assigned to them as appropriate. + + You should define these to the GPIO value as given directly to + the generic GPIO functions. + CONFIG_SYS_I2C_INIT_BOARD When a board is reset during an i2c bus transfer diff --git a/drivers/i2c/soft_i2c.c b/drivers/i2c/soft_i2c.c index e0cf1e10d..1a1809ac1 100644 --- a/drivers/i2c/soft_i2c.c +++ b/drivers/i2c/soft_i2c.c @@ -51,6 +51,58 @@ #endif #include <i2c.h> +#if defined(CONFIG_SOFT_I2C_GPIO_SCL) +# include <asm/gpio.h> + +# ifndef I2C_GPIO_SYNC +# define I2C_GPIO_SYNC +# endif + +# ifndef I2C_INIT +# define I2C_INIT \ + do { \ + gpio_request(CONFIG_SOFT_I2C_GPIO_SCL, "soft_i2c"); \ + gpio_request(CONFIG_SOFT_I2C_GPIO_SDA, "soft_i2c"); \ + } while (0) +# endif + +# ifndef I2C_ACTIVE +# define I2C_ACTIVE do { } while (0) +# endif + +# ifndef I2C_TRISTATE +# define I2C_TRISTATE do { } while (0) +# endif + +# ifndef I2C_READ +# define I2C_READ gpio_get_value(CONFIG_SOFT_I2C_GPIO_SDA) +# endif + +# ifndef I2C_SDA +# define I2C_SDA(bit) \ + do { \ + if (bit) \ + gpio_direction_input(CONFIG_SOFT_I2C_GPIO_SDA); \ + else \ + gpio_direction_output(CONFIG_SOFT_I2C_GPIO_SDA, 0); \ + I2C_GPIO_SYNC; \ + } while (0) +# endif + +# ifndef I2C_SCL +# define I2C_SCL(bit) \ + do { \ + gpio_direction_output(CONFIG_SOFT_I2C_GPIO_SCL, bit); \ + I2C_GPIO_SYNC; \ + } while (0) +# endif + +# ifndef I2C_DELAY +# define I2C_DELAY udelay(5) /* 1/4 I2C clock duration */ +# endif + +#endif + /* #define DEBUG_I2C */ #ifdef DEBUG_I2C |