Re: [PATCH 06/10] clk: amlogic: PLL reset signal supports active-low configuration

[Jian Hu <jian.hu@amlogic.com>]

On 5/14/2026 11:16 PM, Jerome Brunet wrote:
> [ EXTERNAL EMAIL ]
>
> On lun. 11 mai 2026 at 20:47, Jian Hu via B4 Relay <devnull+jian.hu.amlogic.com@kernel.org> wrote:
>
>> From: Jian Hu <jian.hu@amlogic.com>
>>
>> In the A9 design, the PLL reset signal is configured as active-low.
>>
>> Add the flag 'CLK_MESON_PLL_RST_N' to indicate that the PLL reset signal
>> is active-low.
>>
>> Signed-off-by: Jian Hu <jian.hu@amlogic.com>
>> ---
>>   drivers/clk/meson/clk-pll.c | 42 +++++++++++++++++++++++++++++++-----------
>>   drivers/clk/meson/clk-pll.h |  2 ++
>>   2 files changed, 33 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
>> index 5a0bd75f85a9..8568ad6ba7b6 100644
>> --- a/drivers/clk/meson/clk-pll.c
>> +++ b/drivers/clk/meson/clk-pll.c
>> @@ -295,10 +295,14 @@ static int meson_clk_pll_is_enabled(struct clk_hw *hw)
>>   {
>>        struct clk_regmap *clk = to_clk_regmap(hw);
>>        struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
>> +     unsigned int rst;
>>
>> -     if (MESON_PARM_APPLICABLE(&pll->rst) &&
>> -         meson_parm_read(clk->map, &pll->rst))
>> -             return 0;
>> +     if (MESON_PARM_APPLICABLE(&pll->rst)) {
>> +             rst = meson_parm_read(clk->map, &pll->rst);
>> +             if ((rst && !(pll->flags & CLK_MESON_PLL_RST_ACTIVE_LOW)) ||
>> +                 (!rst && (pll->flags & CLK_MESON_PLL_RST_ACTIVE_LOW)))
> Again not a great usage of binary ops. What you've written above is the
> verbose version of a XOR.
>
> The code duplication remarks applies to the rest of the patch too


Ok, I will update this and the other similar instances below in the next 
version.

Here is the updated code for it:

     int active_low = !!(pll->flags & CLK_MESON_PLL_RST_ACTIVE_LOW);

     if (MESON_PARM_APPLICABLE(&pll->rst) &&
                 (meson_parm_read(clk->map, &pll->rst) ^ active_low))

[...]


Best regards,

Jian



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