[linux-sunxi] Re: [PATCH 1/7] clk: sunxi: Add post clk divider for factor clocks

[Chen-Yu Tsai]

Hi,

On Sat, Sep 13, 2014 at 10:43 PM, Emilio López <emilio at elopez.com.ar> wrote:
> Hi,
>
> El 06/09/14 a las 07:47, Chen-Yu Tsai escibió:
>
>> Some factor clocks, mostly PLLs, have an extra fixed divider just before
>> the clock output. Add an option to the factor clk driver config data to
>> specify this divider.
>>
>> Signed-off-by: Chen-Yu Tsai <wens at csie.org>
>> ---
>>   drivers/clk/sunxi/clk-factors.c | 3 +++
>>   drivers/clk/sunxi/clk-factors.h | 1 +
>>   2 files changed, 4 insertions(+)
>>
>> diff --git a/drivers/clk/sunxi/clk-factors.c
>> b/drivers/clk/sunxi/clk-factors.c
>> index 2057c8a..435111d 100644
>> --- a/drivers/clk/sunxi/clk-factors.c
>> +++ b/drivers/clk/sunxi/clk-factors.c
>> @@ -64,6 +64,9 @@ static unsigned long clk_factors_recalc_rate(struct
>> clk_hw *hw,
>>         /* Calculate the rate */
>>         rate = (parent_rate * (n + config->n_start) * (k + 1) >> p) / (m +
>> 1);
>>
>> +       if (config->post_div)
>> +               rate /= config->post_div;
>> +
>>         return rate;
>>   }
>>
>> diff --git a/drivers/clk/sunxi/clk-factors.h
>> b/drivers/clk/sunxi/clk-factors.h
>> index d2d0efa..ce70c65 100644
>> --- a/drivers/clk/sunxi/clk-factors.h
>> +++ b/drivers/clk/sunxi/clk-factors.h
>> @@ -16,6 +16,7 @@ struct clk_factors_config {
>>         u8 pshift;
>>         u8 pwidth;
>>         u8 n_start;
>> +       u8 post_div;
>>   };
>>
>>   struct clk_factors {
>>
>
> For the record, I liked your solution on[1] more, as it's in line with what
> we're doing on the other sunxi platforms, instead of adding features in
> factors to cover for some cases. But it's your and Maxime's call, as I
> haven't written any of the sun6i code so far.

I'm OK either way. It's really up to Maxime whether he likes the DT
representation.

> Cheers!
>
> Emilio
>
> [1] https://patchwork.kernel.org/patch/4228541/