I2C: Add i2c_get/set_speed() to mxc_i2c.c

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Acked-by: Heiko Schocher <hs@denx.de>
master
Marek Vasut 13 years ago committed by Albert ARIBAUD
parent 47af6f61bc
commit b567b8ff79
  1. 31
      drivers/i2c/mxc_i2c.c

@ -95,7 +95,7 @@ static u16 i2c_clk_div[50][2] = {
{ 3072, 0x1E }, { 3840, 0x1F }
};
static u8 clk_idx;
static u8 clk_div;
/*
* Calculate and set proper clock divider
@ -105,7 +105,6 @@ static void i2c_imx_set_clk(unsigned int rate)
struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
unsigned int i2c_clk_rate;
unsigned int div;
int i;
#if defined(CONFIG_MX31)
struct clock_control_regs *sc_regs =
@ -120,16 +119,15 @@ static void i2c_imx_set_clk(unsigned int rate)
i2c_clk_rate = mxc_get_clock(MXC_IPG_PERCLK);
div = (i2c_clk_rate + rate - 1) / rate;
if (div < i2c_clk_div[0][0])
i = 0;
clk_div = 0;
else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
i = ARRAY_SIZE(i2c_clk_div) - 1;
clk_div = ARRAY_SIZE(i2c_clk_div) - 1;
else
for (i = 0; i2c_clk_div[i][0] < div; i++)
for (clk_div = 0; i2c_clk_div[clk_div][0] < div; clk_div++)
;
/* Store divider value */
clk_idx = i2c_clk_div[i][1];
writeb(clk_idx, &i2c_regs->ifdr);
writeb(i2c_clk_div[clk_div][1], &i2c_regs->ifdr);
}
/*
@ -153,6 +151,23 @@ void i2c_init(int speed, int unused)
}
/*
* Set I2C Speed
*/
int i2c_set_bus_speed(unsigned int speed)
{
i2c_init(speed, 0);
return 0;
}
/*
* Get I2C Speed
*/
unsigned int i2c_get_bus_speed(void)
{
return mxc_get_clock(MXC_IPG_PERCLK) / i2c_clk_div[clk_div][0];
}
/*
* Wait for bus to be busy (or free if for_busy = 0)
*
* for_busy = 1: Wait for IBB to be asserted
@ -218,7 +233,7 @@ int i2c_imx_start(void)
unsigned int temp = 0;
int result;
writeb(clk_idx, &i2c_regs->ifdr);
writeb(i2c_clk_div[clk_div][1], &i2c_regs->ifdr);
/* Enable I2C controller */
writeb(0, &i2c_regs->i2sr);

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