The driver assumes that the input selection register (TIM_TISEL) is at its reset default value. Usually this is the case, but the bootloader might have modified it. This bases on a similar patch submitted by Olivier Moysan for pwm-stm32. Reviewed-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> --- Changes since (implicit) v1 sent with Message-Id: 20230412153709.3557323-1-u.kleine-koenig@xxxxxxxxxxxxxx . - Only reset TIM_TISEL as suggested by Fabrice - Add Fabrice's Review tag drivers/counter/stm32-timer-cnt.c | 3 +++ include/linux/mfd/stm32-timers.h | 1 + 2 files changed, 4 insertions(+) diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c index 9bf20a5d6bda..6206d2dc3d47 100644 --- a/drivers/counter/stm32-timer-cnt.c +++ b/drivers/counter/stm32-timer-cnt.c @@ -342,6 +342,9 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) platform_set_drvdata(pdev, priv); + /* Reset input selector to its default input */ + regmap_write(priv->regmap, TIM_TISEL, 0x0); + /* Register Counter device */ ret = devm_counter_add(dev, counter); if (ret < 0) diff --git a/include/linux/mfd/stm32-timers.h b/include/linux/mfd/stm32-timers.h index 5f5c43fd69dd..1b94325febb3 100644 --- a/include/linux/mfd/stm32-timers.h +++ b/include/linux/mfd/stm32-timers.h @@ -31,6 +31,7 @@ #define TIM_BDTR 0x44 /* Break and Dead-Time Reg */ #define TIM_DCR 0x48 /* DMA control register */ #define TIM_DMAR 0x4C /* DMA register for transfer */ +#define TIM_TISEL 0x68 /* Input Selection */ #define TIM_CR1_CEN BIT(0) /* Counter Enable */ #define TIM_CR1_DIR BIT(4) /* Counter Direction */ base-commit: fe15c26ee26efa11741a7b632e9f23b01aca4cc6 -- 2.39.2