Hello Billy,
just two minor thing left to criticise:
On Mon, Nov 29, 2021 at 02:43:29PM +0800, Billy Tsai wrote:
> + if (clk_en && duty_pt) {
> + dividend = (u64)NSEC_PER_SEC * (div_l + 1) * duty_pt
> + << div_h;
> + state->duty_cycle = DIV_ROUND_UP_ULL(dividend, rate);
> + } else
> + state->duty_cycle = clk_en ? state->period : 0;
I wonder about checkpatch not criticising this construct. See
Documentation/process/coding-style.rst:
Do not unnecessarily use braces where a single statement will
do. [...] This does not apply if only one branch of a
conditional statement is a single statement; in the latter case
use braces in both branches
> [...]
> +static int aspeed_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
> + const struct pwm_state *state)
> +{
> + struct device *dev = chip->dev;
> + struct aspeed_pwm_data *priv = aspeed_pwm_chip_to_data(chip);
> + u32 hwpwm = pwm->hwpwm, duty_pt;
> + unsigned long rate;
> + u64 div_h, div_l, divisor, expect_period;
> + bool clk_en;
> +
> + expect_period = state->period;
> + dev_dbg(dev, "expect period: %lldns, duty_cycle: %lldns", expect_period,
> + state->duty_cycle);
> +
> + rate = clk_get_rate(priv->clk);
> + if (expect_period > div64_u64(ULLONG_MAX, (u64)rate))
> + expect_period = div64_u64(ULLONG_MAX, (u64)rate);
If you write that as
expect_period = min(div64_u64(ULLONG_MAX, (u64)rate), expect_period);
you make sure that the division is only calculated once.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
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