Re: [PATCH v2 04/10] clk: qcom: Add support for PLLs with alpha mode

Rajendra Nayak
2016-08-25T09:23:05Z

On 08/24/2016 11:45 AM, Stephen Boyd wrote:
> On 08/11, Rajendra Nayak wrote:
>> Some PLLs can support an alpha mode, and a single alpha
>> register (instead of registers to program the M/N values),
>> the contents of which depend on the alpha mode selected.
>> (They are either treated as two's complement or M/N value)
>
> That's just a sentence, so please drop the parentheses.

OK

>
>> Add support for this in the clk PLL driver.
>>
>
> I'm confused, don't we already have clk-alpha-pll.c to handle
> alpha type plls? What are we doing adding support to the "legacy"
> pll code?

Yes, this does look confusing now that I took a relook at it all.
I will redo this whole thing so it fits into the alpha PLL support that
we already have.

>
>> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
>> ---
>> drivers/clk/qcom/clk-pll.c | 8 ++++++--
>> drivers/clk/qcom/clk-pll.h | 2 ++
>> 2 files changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/clk/qcom/clk-pll.c b/drivers/clk/qcom/clk-pll.c
>> index 5b940d6..08d2fa2 100644
>> --- a/drivers/clk/qcom/clk-pll.c
>> +++ b/drivers/clk/qcom/clk-pll.c
>> @@ -255,8 +255,12 @@ static void clk_pll_configure(struct clk_pll *pll, struct regmap *regmap,
>> u32 mask;
>>
>> regmap_write(regmap, pll->l_reg, config->l);
>> - regmap_write(regmap, pll->m_reg, config->m);
>> - regmap_write(regmap, pll->n_reg, config->n);
>> + if (pll->alpha_reg) {
>
> This assumes that alpha_reg is not 0 offset from base, which
> seems like a bad assumption to make.

sure, I need to handle this in a better way

>
>> + regmap_write(regmap, pll->alpha_reg, config->alpha);
>> + } else {
>> + regmap_write(regmap, pll->m_reg, config->m);
>> + regmap_write(regmap, pll->n_reg, config->n);
>> + }
>>
>> val = config->vco_val;
>> val |= config->pre_div_val;
>>
>

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