* FAILED: patch "[PATCH] gpio: mvebu: fix pwm .get_state period calculation" failed to apply to 4.14-stable tree
@ 2021-01-25 14:44 gregkh
0 siblings, 0 replies; only message in thread
From: gregkh @ 2021-01-25 14:44 UTC (permalink / raw)
To: baruch, bgolaszewski, linux, u.kleine-koenig; +Cc: stable
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From e73b0101ae5124bf7cd3fb5d250302ad2f16a416 Mon Sep 17 00:00:00 2001
From: Baruch Siach <baruch@tkos.co.il>
Date: Sun, 17 Jan 2021 15:17:02 +0200
Subject: [PATCH] gpio: mvebu: fix pwm .get_state period calculation
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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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>
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)
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2021-01-25 14:44 FAILED: patch "[PATCH] gpio: mvebu: fix pwm .get_state period calculation" failed to apply to 4.14-stable tree gregkh
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