From: Uwe Kleine-König u.kleine-koenig@pengutronix.de
stable inclusion from stable-v5.10.122 commit 572211d631d7665c6690b5a6cb80436f8c368dc1 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5W6OE
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 5e3b07ca5cc78cd4a987e78446849e41288d87cb ]
The hardware only supports periods <= 1.6 ms and if a bigger period is requested it is clamped to 1.6 ms. In this case duty_cycle might be bigger than 1.6 ms and then the duty cycle register is written with a value bigger than LP3943_MAX_DUTY. So clamp duty_cycle accordingly.
Fixes: af66b3c0934e ("pwm: Add LP3943 PWM driver") Signed-off-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Signed-off-by: Thierry Reding thierry.reding@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- drivers/pwm/pwm-lp3943.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/pwm/pwm-lp3943.c b/drivers/pwm/pwm-lp3943.c index bf3f14fb5f24..05e4120fd702 100644 --- a/drivers/pwm/pwm-lp3943.c +++ b/drivers/pwm/pwm-lp3943.c @@ -125,6 +125,7 @@ static int lp3943_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, if (err) return err;
+ duty_ns = min(duty_ns, period_ns); val = (u8)(duty_ns * LP3943_MAX_DUTY / period_ns);
return lp3943_write_byte(lp3943, reg_duty, val);