Hello Baruch,
$Subject ~= s/get_state/.get_state/ ?
On Mon, Jan 11, 2021 at 01:17:02PM +0200, Baruch Siach wrote:
> The period is the sum of on and off values.
>
> Reported-by: Russell King <linux@xxxxxxxxxxxxxxx>
> Fixes: 757642f9a584e ("gpio: mvebu: Add limited PWM support")
> Signed-off-by: Baruch Siach <baruch@xxxxxxxxxx>
> ---
> drivers/gpio/gpio-mvebu.c | 19 ++++++++-----------
> 1 file changed, 8 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
> index 672681a976f5..a912a8fed197 100644
> --- a/drivers/gpio/gpio-mvebu.c
> +++ b/drivers/gpio/gpio-mvebu.c
> @@ -676,20 +676,17 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip,
> else
> state->duty_cycle = 1;
>
> + val = (unsigned long long) u; /* on duration */
> regmap_read(mvpwm->regs, mvebu_pwmreg_blink_off_duration(mvpwm), &u);
> - val = (unsigned long long) u * NSEC_PER_SEC;
> + val += (unsigned long long) u; /* period = on + off duration */
> + val *= NSEC_PER_SEC;
> do_div(val, mvpwm->clk_rate);
> - if (val < state->duty_cycle) {
> + if (val > UINT_MAX)
> + state->period = UINT_MAX;
> + else if (val)
> + state->period = val;
> + else
> state->period = 1;
> - } else {
> - val -= state->duty_cycle;
> - if (val > UINT_MAX)
> - state->period = UINT_MAX;
> - else if (val)
> - state->period = val;
> - else
> - state->period = 1;
> - }
The patch looks good, the patch description could be a bit more verbose.
Something like:
Calculate the period as
($on + $off) / clkrate
instead of
$off / clkrate - $on / clkrate
.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
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