The patch below does not apply to the 6.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.9.y git checkout FETCH_HEAD git cherry-pick -x c45fcf46ca2368dafe7e5c513a711a6f0f974308 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024062455-green-reach-3f21@gregkh' --subject-prefix 'PATCH 6.9.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From c45fcf46ca2368dafe7e5c513a711a6f0f974308 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= u.kleine-koenig@baylibre.com Date: Fri, 21 Jun 2024 16:37:12 +0200 Subject: [PATCH] pwm: stm32: Refuse too small period requests MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

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

diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c index a2f231d13a9f..3e7b2a8e34e7 100644 --- a/drivers/pwm/pwm-stm32.c +++ b/drivers/pwm/pwm-stm32.c @@ -337,6 +337,8 @@ static int stm32_pwm_config(struct stm32_pwm *priv, unsigned int ch,

prd = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk), (u64)NSEC_PER_SEC * (prescaler + 1)); + if (!prd) + return -EINVAL;

/* * All channels share the same prescaler and counter so when two