4.19-stable review patch. If anyone has any objections, please let me know.
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From: Uwe Kleine-König u.kleine-koenig@baylibre.com
commit c45fcf46ca2368dafe7e5c513a711a6f0f974308 upstream.
If period_ns is small, prd might well become 0. Catch that case because otherwise with
regmap_write(priv->regmap, TIM_ARR, prd - 1);
a few lines down quite a big period is configured.
Fixes: 7edf7369205b ("pwm: Add driver for STM32 plaftorm") Cc: stable@vger.kernel.org Reviewed-by: Trevor Gamblin tgamblin@baylibre.com Signed-off-by: Uwe Kleine-König u.kleine-koenig@baylibre.com Link: https://lore.kernel.org/r/b86f62f099983646f97eeb6bfc0117bb2d0c340d.171897915... Signed-off-by: Uwe Kleine-König ukleinek@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pwm/pwm-stm32.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/pwm/pwm-stm32.c +++ b/drivers/pwm/pwm-stm32.c @@ -337,6 +337,9 @@ static int stm32_pwm_config(struct stm32
prd = div;
+ if (!prd) + return -EINVAL; + if (prescaler > MAX_TIM_PSC) return -EINVAL;