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author | Mike Frysinger <vapier@gentoo.org> | 2010-07-21 13:38:02 -0400 |
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committer | Heiko Schocher <hs@denx.de> | 2010-07-22 08:03:47 +0200 |
commit | 793b5726f7e998c7cec93ea5ee7910dd6ddb1e5e (patch) | |
tree | 5568b9f089ea3ef901098741c964b3d7a5b65c6b /drivers/i2c/soft_i2c.c | |
parent | 1f82ff4777f360e92aa37bbbed647f7b9d9d2044 (diff) | |
download | u-boot-imx-793b5726f7e998c7cec93ea5ee7910dd6ddb1e5e.zip u-boot-imx-793b5726f7e998c7cec93ea5ee7910dd6ddb1e5e.tar.gz u-boot-imx-793b5726f7e998c7cec93ea5ee7910dd6ddb1e5e.tar.bz2 |
i2c: soft_i2c: add simple GPIO implementation
Since the vast majority of GPIO I2C implementations behave the same way,
support the common GPIO framework with default settings.
This adds two new defines CONFIG_SOFT_I2C_GPIO_{SCL,SDA} so that boards
which want GPIO I2C support need only define these.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Tested-by: Thomas Chou <thomas@wytron.com.tw>
Diffstat (limited to 'drivers/i2c/soft_i2c.c')
-rw-r--r-- | drivers/i2c/soft_i2c.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/drivers/i2c/soft_i2c.c b/drivers/i2c/soft_i2c.c index e0cf1e1..1a1809a 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 |