summaryrefslogtreecommitdiff
path: root/drivers/gpio
diff options
context:
space:
mode:
authorBaruch Siach <baruch@tkos.co.il>2021-01-17 15:17:02 +0200
committerBartosz Golaszewski <bgolaszewski@baylibre.com>2021-01-19 11:58:22 +0100
commite73b0101ae5124bf7cd3fb5d250302ad2f16a416 (patch)
treef83b2e8f9fe0d35e1e9c2dc4278e5b0c757ad7fa /drivers/gpio
parentef38237444ce952daf041ed2885918f9f7d1e997 (diff)
gpio: mvebu: fix pwm .get_state period calculation
The period is the sum of on and off values. That is, calculate period as ($on + $off) / clkrate instead of $off / clkrate - $on / clkrate that makes no sense. Reported-by: Russell King <linux@armlinux.org.uk> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Fixes: 757642f9a584e ("gpio: mvebu: Add limited PWM support") Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/gpio-mvebu.c19
1 files 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;
- }
regmap_read(mvchip->regs, GPIO_BLINK_EN_OFF + mvchip->offset, &u);
if (u)