counter: stm32-timer-cnt: Reset TIM_TISEL to its default value in probe

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@foss.st.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230413212339.3611722-1-u.kleine-koenig@pengutronix.de/
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>

diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c
index 9bf20a5..6206d2d 100644 (file)
--- 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)