pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional

[ Upstream commit 43efdc8f0e6d7088ec61bd55a73bf853f002d043 ]

In the old code (e.g.) mutex_destroy() was called before
pwmchip_remove(). Between these two calls it is possible that a PWM
callback is used which tries to grab the mutex.

Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers")
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>

diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c
index 2d585c1..c6e710a 100644 (file)
--- a/drivers/pwm/pwm-omap-dmtimer.c
+++ b/drivers/pwm/pwm-omap-dmtimer.c
@@ -364,6 +364,11 @@ put:
 static int pwm_omap_dmtimer_remove(struct platform_device *pdev)
 {
        struct pwm_omap_dmtimer_chip *omap = platform_get_drvdata(pdev);
+       int ret;
+
+       ret = pwmchip_remove(&omap->chip);
+       if (ret)
+               return ret;
 
        if (pm_runtime_active(&omap->dm_timer_pdev->dev))
                omap->pdata->stop(omap->dm_timer);
@@ -372,7 +377,7 @@ static int pwm_omap_dmtimer_remove(struct platform_device *pdev)
 
        mutex_destroy(&omap->mutex);
 
-       return pwmchip_remove(&omap->chip);
+       return 0;
 }
 
 static const struct of_device_id pwm_omap_dmtimer_of_match[] = {