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

David.Wu david.wu at rock-chips.com
Mon Apr 18 06:15:46 PDT 2016

Hi Wolfram,

在 2016/4/16 1:58, Wolfram Sang 写道:
>> 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.
> If I understand you correctly, couldn't you use clk_set_rate() depending
> on the desired scl frequency which is already described in DT as
> clock-frequency?

Yeap, the default input clock rate is too low for HS mode, and it 's 
flexible that
we get it from DT.

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