diff options
Diffstat (limited to 'drivers/i2c/mxc_i2c.c')
| -rw-r--r-- | drivers/i2c/mxc_i2c.c | 37 |
1 files changed, 26 insertions, 11 deletions
diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c index bf3ad956c..c88ac7cf9 100644 --- a/drivers/i2c/mxc_i2c.c +++ b/drivers/i2c/mxc_i2c.c @@ -37,6 +37,7 @@ #include <asm/arch/clock.h> #include <asm/arch/imx-regs.h> +#include <i2c.h> struct mxc_i2c_regs { uint32_t iadr; @@ -99,16 +100,14 @@ static u16 i2c_clk_div[50][2] = { { 3072, 0x1E }, { 3840, 0x1F } }; -static u8 clk_div; - /* * Calculate and set proper clock divider */ -static void i2c_imx_set_clk(unsigned int rate) +static uint8_t i2c_imx_get_clk(unsigned int rate) { - struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; unsigned int i2c_clk_rate; unsigned int div; + u8 clk_div; #if defined(CONFIG_MX31) struct clock_control_regs *sc_regs = @@ -131,7 +130,7 @@ static void i2c_imx_set_clk(unsigned int rate) ; /* Store divider value */ - writeb(i2c_clk_div[clk_div][1], &i2c_regs->ifdr); + return clk_div; } /* @@ -150,7 +149,13 @@ void i2c_reset(void) */ void i2c_init(int speed, int unused) { - i2c_imx_set_clk(speed); + struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; + u8 clk_idx = i2c_imx_get_clk(speed); + u8 idx = i2c_clk_div[clk_idx][1]; + + /* Store divider value */ + writeb(idx, &i2c_regs->ifdr); + i2c_reset(); } @@ -168,6 +173,13 @@ int i2c_set_bus_speed(unsigned int speed) */ unsigned int i2c_get_bus_speed(void) { + struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; + u8 clk_idx = readb(&i2c_regs->ifdr); + u8 clk_div; + + for (clk_div = 0; i2c_clk_div[clk_div][1] != clk_idx; clk_div++) + ; + return mxc_get_clock(MXC_IPG_PERCLK) / i2c_clk_div[clk_div][0]; } @@ -236,8 +248,12 @@ int i2c_imx_start(void) struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; unsigned int temp = 0; int result; + int speed = i2c_get_bus_speed(); + u8 clk_idx = i2c_imx_get_clk(speed); + u8 idx = i2c_clk_div[clk_idx][1]; - writeb(i2c_clk_div[clk_div][1], &i2c_regs->ifdr); + /* Store divider value */ + writeb(idx, &i2c_regs->ifdr); /* Enable I2C controller */ writeb(0, &i2c_regs->i2sr); @@ -310,11 +326,10 @@ int i2c_imx_set_chip_addr(uchar chip, int read) int i2c_imx_set_reg_addr(uint addr, int alen) { struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; - int ret; - int i; + int ret = 0; - for (i = 0; i < (8 * alen); i += 8) { - writeb((addr >> i) & 0xff, &i2c_regs->i2dr); + while (alen--) { + writeb((addr >> (alen * 8)) & 0xff, &i2c_regs->i2dr); ret = i2c_imx_trx_complete(); if (ret) |