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