diff options
Diffstat (limited to 'include/asm-arm/arch-omap3/i2c.h')
| -rw-r--r-- | include/asm-arm/arch-omap3/i2c.h | 70 |
1 files changed, 63 insertions, 7 deletions
diff --git a/include/asm-arm/arch-omap3/i2c.h b/include/asm-arm/arch-omap3/i2c.h index 3937f3525..8b339cce9 100644 --- a/include/asm-arm/arch-omap3/i2c.h +++ b/include/asm-arm/arch-omap3/i2c.h @@ -112,16 +112,72 @@ #define I2C_SCLH_HSSCLH 8 #define I2C_SCLH_HSSCLH_M 0xFF -#define OMAP_I2C_STANDARD 100 -#define OMAP_I2C_FAST_MODE 400 -#define OMAP_I2C_HIGH_SPEED 3400 +#define OMAP_I2C_STANDARD 100000 +#define OMAP_I2C_FAST_MODE 400000 +#define OMAP_I2C_HIGH_SPEED 3400000 -#define SYSTEM_CLOCK_12 12000 -#define SYSTEM_CLOCK_13 13000 -#define SYSTEM_CLOCK_192 19200 -#define SYSTEM_CLOCK_96 96000 +#define SYSTEM_CLOCK_12 12000000 +#define SYSTEM_CLOCK_13 13000000 +#define SYSTEM_CLOCK_192 19200000 +#define SYSTEM_CLOCK_96 96000000 +/* Use the reference value of 96MHz if not explicitly set by the board */ +#ifndef I2C_IP_CLK #define I2C_IP_CLK SYSTEM_CLOCK_96 +#endif + +/* + * The reference minimum clock for high speed is 19.2MHz. + * The linux 2.6.30 kernel uses this value. + * The reference minimum clock for fast mode is 9.6MHz + * The reference minimum clock for standard mode is 4MHz + * In TRM, the value of 12MHz is used. + */ +#ifndef I2C_INTERNAL_SAMPLING_CLK +#define I2C_INTERNAL_SAMPLING_CLK 19200000 +#endif + +/* + * The equation for the low and high time is + * tlow = scll + scll_trim = (sampling clock * tlow_duty) / speed + * thigh = sclh + sclh_trim = (sampling clock * (1 - tlow_duty)) / speed + * + * If the duty cycle is 50% + * + * tlow = scll + scll_trim = sampling clock / (2 * speed) + * thigh = sclh + sclh_trim = sampling clock / (2 * speed) + * + * In TRM + * scll_trim = 7 + * sclh_trim = 5 + * + * The linux 2.6.30 kernel uses + * scll_trim = 6 + * sclh_trim = 6 + * + * These are the trim values for standard and fast speed + */ +#ifndef I2C_FASTSPEED_SCLL_TRIM +#define I2C_FASTSPEED_SCLL_TRIM 6 +#endif +#ifndef I2C_FASTSPEED_SCLH_TRIM +#define I2C_FASTSPEED_SCLH_TRIM 6 +#endif + +/* These are the trim values for high speed */ +#ifndef I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM +#define I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM I2C_FASTSPEED_SCLL_TRIM +#endif +#ifndef I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM +#define I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM I2C_FASTSPEED_SCLH_TRIM +#endif +#ifndef I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM +#define I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM I2C_FASTSPEED_SCLL_TRIM +#endif +#ifndef I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM +#define I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM I2C_FASTSPEED_SCLH_TRIM +#endif + #define I2C_PSC_MAX 0x0f #define I2C_PSC_MIN 0x00 |