This is a note to let you know that I've just added the patch titled
pwm: bcm-iproc: handle clk_get_rate() return
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pwm-bcm-iproc-handle-clk_get_rate-return.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5470722e27f17e5e9899bc5bf2c2727a8231901f
Author: Rayagonda Kokatanur <rayagonda.kokatanur@xxxxxxxxxxxx>
Date: Fri Jul 17 21:46:06 2020 -0700
pwm: bcm-iproc: handle clk_get_rate() return
[ Upstream commit 6ced5ff0be8e94871ba846dfbddf69d21363f3d7 ]
Handle clk_get_rate() returning 0 to avoid possible division by zero.
Fixes: daa5abc41c80 ("pwm: Add support for Broadcom iProc PWM controller")
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@xxxxxxxxxxxx>
Signed-off-by: Scott Branden <scott.branden@xxxxxxxxxxxx>
Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pwm/pwm-bcm-iproc.c b/drivers/pwm/pwm-bcm-iproc.c
index 31b01035d0ab3..8cfba3614e601 100644
--- a/drivers/pwm/pwm-bcm-iproc.c
+++ b/drivers/pwm/pwm-bcm-iproc.c
@@ -85,8 +85,6 @@ static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
u64 tmp, multi, rate;
u32 value, prescale;
- rate = clk_get_rate(ip->clk);
-
value = readl(ip->base + IPROC_PWM_CTRL_OFFSET);
if (value & BIT(IPROC_PWM_CTRL_EN_SHIFT(pwm->hwpwm)))
@@ -99,6 +97,13 @@ static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
else
state->polarity = PWM_POLARITY_INVERSED;
+ rate = clk_get_rate(ip->clk);
+ if (rate == 0) {
+ state->period = 0;
+ state->duty_cycle = 0;
+ return;
+ }
+
value = readl(ip->base + IPROC_PWM_PRESCALE_OFFSET);
prescale = value >> IPROC_PWM_PRESCALE_SHIFT(pwm->hwpwm);
prescale &= IPROC_PWM_PRESCALE_MAX;
