[PATCH] i2c: rk3x: fix divisor calculation for SCL frequency
dianders at chromium.org
Fri Sep 5 08:20:23 PDT 2014
On Fri, Sep 5, 2014 at 3:17 AM, addy ke <addy.ke at rock-chips.com> wrote:
> The following modifications is reasonable?
> static void rk3x_i2c_set_scl_rate(struct rk3x_i2c *i2c, unsigned long scl_rate)
> unsigned long i2c_rate = clk_get_rate(i2c->clk);
> unsigned int div;
> /* set DIV = DIVH = DIVL
> * SCL rate = (clk rate) / (8 * (DIVH + 1 + DIVL + 1))
> * = (clk rate) / (16 * (DIV + 1))
> div = DIV_ROUND_UP(i2c_rate, scl_rate * 16) - 1;
> i2c_writel(i2c, (div << 16) | (div & 0xffff), REG_CLKDIV);
Yes, that looks much cleaner and is a nice solution, thanks! Can you
send up a new patch version?
More information about the Linux-rockchip