[PATCH v2 4/4] ARM: PWM: add allwinner sun8i pwm support.

Hao Zhang hao5781286 at gmail.com
Mon May 14 07:45:44 PDT 2018


2018-02-26 17:00 GMT+08:00 Maxime Ripard <maxime.ripard at bootlin.com>:
> Hi,
>
> Thanks for respinning this serie. It looks mostly good, but you still
> have a quite significant number of checkpatch (--strict) warnings that
> you should address.

Thanks for reviews :) ,i'm sorry for that, it will be fixed next time.
and, besides, in what situation were the checkpatch warning can be ignore?

>
> On Sun, Feb 25, 2018 at 09:53:08PM +0800, hao_zhang wrote:
>> +#define CAPTURE_IRQ_ENABLE_REG       0x0010
>> +#define CFIE(ch)     BIT(ch << 1 + 1)
>> +#define CRIE(ch)     BIT(ch << 1)
>
> You should also put your argument between parentheses here (and in all
> your other macros).

Do you mean like this ?
#define CFIE(ch)     BIT((ch) << 1 + 1)
#define CRIE(ch)     BIT((ch) << 1)

>
>> +static const u16 div_m_table[] = {
>> +     1,
>> +     2,
>> +     4,
>> +     8,
>> +     16,
>> +     32,
>> +     64,
>> +     128,
>> +     256
>> +};
>
> If this is just a power of two, you can use either the power of two /
> ilog2 to switch back and forth, instead of using that table.

I think using table is more explicit and extended...

>
>> +static int sun8i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
>> +             struct pwm_state *state)
>> +{
>> +     int ret;
>> +     struct sun8i_pwm_chip *sun8i_pwm = to_sun8i_pwm_chip(chip);
>> +     struct pwm_state cstate;
>> +
>> +     pwm_get_state(pwm, &cstate);
>> +     if (!cstate.enabled) {
>> +             ret = clk_prepare_enable(sun8i_pwm->clk);
>> +             if (ret) {
>> +                     dev_err(chip->dev, "Failed to enable PWM clock\n");
>> +                     return ret;
>> +             }
>> +     }
>> +
>> +     spin_lock(&sun8i_pwm->ctrl_lock);
>
> What do you need that spinlock for? Can you use a mutex instead?
It should be remove.
>
> Thanks!
> Maxime
>
> --
> Maxime Ripard, Bootlin (formerly Free Electrons)
> Embedded Linux and Kernel engineering
> https://bootlin.com



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