Re: [PATCH v5 2/2] i2c: rk3x: add i2c support for rk3399 soc

From: David.Wu
Date: Fri Apr 15 2016 - 08:10:27 EST


Hi Wolfram,

å 2016/4/15 2:48, Wolfram Sang åé:
+ - input-clk-rate : frequency rate of function clock used(in Hz). If omitted,
+ the default clock rate is used. It is just used at rk3399 soc.
Why is this needed? Why don't we simply use the default or calculate the
best value somehow?
The default frequency rate of function clock is 50M Hz, it can match F/S mode,
but HS mode not. If use default rate 50M to get 1.7M scl-frequency rate , we could not
get accurately 1.7M frequecy rate. The input-clk-rate is more higher, we get more
accurately scl-frequency rate, as 200M is a suitable input-clk-rate.

If 200M was used for F/S mode, it would increase power consumption, so add a option that
could be configured from DT.

+ * @t_calc: Caculated rk3x private timings that would
+ * be written into regs
double space