--- drivers/i2c/fsl_i2c.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 68 insertions(+), 0 deletions(-)
diff --git a/drivers/i2c/fsl_i2c.c b/drivers/i2c/fsl_i2c.c index 0690340..8fd73c0 100644 --- a/drivers/i2c/fsl_i2c.c +++ b/drivers/i2c/fsl_i2c.c @@ -78,6 +78,73 @@ static const struct fsl_i2c *i2c_dev[2] = { * register. See the application note AN2919 "Determining the I2C Frequency * Divider Ratio for SCL" */ +#if defined(CONFIG_MCF547x_8x) || defined(CONFIG_MCF5445x) +static const struct { + u8 fdr; + unsigned short divider; +} fsl_i2c_speed_map[] = { + {.fdr=0x20, .divider= 20}, {.fdr=0x21, .divider= 22}, {.fdr=0x22, .divider= 24}, + {.fdr=0x23, .divider= 26}, {.fdr=0x00, .divider= 28}, {.fdr=0x24, .divider= 28}, + {.fdr=0x01, .divider= 30}, {.fdr=0x25, .divider= 32}, {.fdr=0x02, .divider= 34}, + {.fdr=0x26, .divider= 36}, {.fdr=0x03, .divider= 40}, {.fdr=0x27, .divider= 40}, + {.fdr=0x04, .divider= 44}, {.fdr=0x05, .divider= 48}, /*{.fdr=0x28, .divider= 48},*/ + {.fdr=0x06, .divider= 56}, /*{.fdr=0x29, .divider= 56},*/ {.fdr=0x2A, .divider= 64}, + {.fdr=0x07, .divider= 68}, {.fdr=0x2B, .divider= 72}, {.fdr=0x08, .divider= 80}, + /*{.fdr=0x2C, .divider= 80},*/ {.fdr=0x09, .divider= 88}, {.fdr=0x2D, .divider= 96}, + {.fdr=0x0A, .divider= 104}, {.fdr=0x2E, .divider= 112}, {.fdr=0x0B, .divider= 128}, + /*{.fdr=0x2F, .divider= 128},*/ {.fdr=0x0C, .divider= 144}, {.fdr=0x0D, .divider= 160}, + /*{.fdr=0x30, .divider= 160},*/ {.fdr=0x0E, .divider= 192}, /*{.fdr=0x31, .divider= 192},*/ + {.fdr=0x32, .divider= 224}, {.fdr=0x0F, .divider= 240}, {.fdr=0x33, .divider= 256}, + {.fdr=0x10, .divider= 288}, {.fdr=0x11, .divider= 320}, /*{.fdr=0x34, .divider= 320},*/ + {.fdr=0x12, .divider= 384}, /*{.fdr=0x35, .divider= 384},*/ {.fdr=0x36, .divider= 448}, + /*{.fdr=0x13, .divider= 480},*/ {.fdr=0x37, .divider= 512}, {.fdr=0x14, .divider= 576}, + {.fdr=0x15, .divider= 640}, /*{.fdr=0x38, .divider= 640},*/ {.fdr=0x16, .divider= 768}, + /*{.fdr=0x39, .divider= 768},*/ {.fdr=0x3A, .divider= 896}, {.fdr=0x17, .divider= 960}, + {.fdr=0x3B, .divider=1024}, {.fdr=0x18, .divider=1152}, {.fdr=0x19, .divider=1280}, + /*{.fdr=0x3C, .divider=1280},*/ {.fdr=0x1A, .divider=1536}, /*{.fdr=0x3D, .divider=1536},*/ + {.fdr=0x3E, .divider=1792}, {.fdr=0x1B, .divider=1920}, {.fdr=0x3F, .divider=2048}, + {.fdr=0x1C, .divider=2304}, {.fdr=0x1D, .divider=2560}, {.fdr=0x1E, .divider=3072}, + {.fdr=0x1F, .divider=3840}, {.fdr=0x00, .divider=-1} +}; + +/** + * Set the I2C bus speed for a given I2C device + * + * @param dev: the I2C device + * @i2c_clk: I2C bus clock frequency + * @speed: the desired speed of the bus + * + * The I2C device must be stopped before calling this function. + * + * The return value is the actual bus speed that is set. + */ +static unsigned int set_i2c_bus_speed(const struct fsl_i2c *dev, + unsigned int i2c_clk, unsigned int speed) +{ + unsigned short divider = min(i2c_clk / speed, (unsigned short) -1); + unsigned int i; + u8 fdr = 0; + + /* + * We want to choose an FDR/DFSR that generates an I2C bus speed that + * is equal to or lower than the requested speed. That means that we + * want the first divider that is equal to or greater than the + * calculated divider. + */ + + for (i = 0; i < ARRAY_SIZE(fsl_i2c_speed_map); i++) + if (fsl_i2c_speed_map[i].divider >= divider) { + fdr = fsl_i2c_speed_map[i].fdr; + speed = i2c_clk / fsl_i2c_speed_map[i].divider; + break; + } + + writeb(fdr, &dev->fdr); /* set bus speed */ + + return speed; +} +#else /* ! (defined(CONFIG_MCF547x_8x) || defined(CONFIG_MCF5445x) */ + static const struct { unsigned short divider; u8 dfsr; @@ -140,6 +207,7 @@ static unsigned int set_i2c_bus_speed(const struct fsl_i2c *dev,
return speed; } +#endif /* if (defined(CONFIG_MCF547x_8x) || defined(CONFIG_MCF5445x) */
void i2c_init(int speed, int slaveadd)