[PATCH] pwm: Call pwm_enable() before pwm_config()
Benoît Thébaudeau
benoit.thebaudeau at advansee.com
Thu Aug 23 10:19:47 EDT 2012
Some PWM drivers enable the clock of the PWM peripheral in pwm_enable(). Hence,
for these drivers, a call to pwm_config() does not have any effect before
pwm_enable() has been called.
This patch fixes the PWM users to make sure that they call pwm_enable() before
pwm_config().
This fixes the first setting of brightness through sysfs that had no effect with
leds-pwm and the i.MX PWM driver.
Cc: Thierry Reding <thierry.reding at avionic-design.de>
Cc: <linux-kernel at vger.kernel.org>
Cc: Sascha Hauer <kernel at pengutronix.de>
Cc: <linux-arm-kernel at lists.infradead.org>
Cc: Dmitry Torokhov <dmitry.torokhov at gmail.com>
Cc: <linux-input at vger.kernel.org>
Cc: Bryan Wu <bryan.wu at canonical.com>
Cc: Richard Purdie <rpurdie at rpsys.net>
Cc: <linux-leds at vger.kernel.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat at gmx.de>
Cc: <linux-fbdev at vger.kernel.org>
Cc: Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
---
.../drivers/input/misc/pwm-beeper.c | 6 +++---
.../drivers/leds/leds-pwm.c | 2 +-
.../drivers/video/backlight/pwm_bl.c | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git linux-next-c94456b.orig/drivers/input/misc/pwm-beeper.c linux-next-c94456b/drivers/input/misc/pwm-beeper.c
index fc84c8a..97d322b 100644
--- linux-next-c94456b.orig/drivers/input/misc/pwm-beeper.c
+++ linux-next-c94456b/drivers/input/misc/pwm-beeper.c
@@ -53,10 +53,10 @@ static int pwm_beeper_event(struct input_dev *input,
pwm_disable(beeper->pwm);
} else {
period = HZ_TO_NANOSECONDS(value);
- ret = pwm_config(beeper->pwm, period / 2, period);
+ ret = pwm_enable(beeper->pwm);
if (ret)
return ret;
- ret = pwm_enable(beeper->pwm);
+ ret = pwm_config(beeper->pwm, period / 2, period);
if (ret)
return ret;
beeper->period = period;
@@ -156,8 +156,8 @@ static int pwm_beeper_resume(struct device *dev)
struct pwm_beeper *beeper = dev_get_drvdata(dev);
if (beeper->period) {
- pwm_config(beeper->pwm, beeper->period / 2, beeper->period);
pwm_enable(beeper->pwm);
+ pwm_config(beeper->pwm, beeper->period / 2, beeper->period);
}
return 0;
diff --git linux-next-c94456b.orig/drivers/leds/leds-pwm.c linux-next-c94456b/drivers/leds/leds-pwm.c
index f2e44c7..c2e0c22 100644
--- linux-next-c94456b.orig/drivers/leds/leds-pwm.c
+++ linux-next-c94456b/drivers/leds/leds-pwm.c
@@ -42,8 +42,8 @@ static void led_pwm_set(struct led_classdev *led_cdev,
pwm_config(led_dat->pwm, 0, period);
pwm_disable(led_dat->pwm);
} else {
- pwm_config(led_dat->pwm, brightness * period / max, period);
pwm_enable(led_dat->pwm);
+ pwm_config(led_dat->pwm, brightness * period / max, period);
}
}
diff --git linux-next-c94456b.orig/drivers/video/backlight/pwm_bl.c linux-next-c94456b/drivers/video/backlight/pwm_bl.c
index 995f016..a4bb95c 100644
--- linux-next-c94456b.orig/drivers/video/backlight/pwm_bl.c
+++ linux-next-c94456b/drivers/video/backlight/pwm_bl.c
@@ -65,8 +65,8 @@ static int pwm_backlight_update_status(struct backlight_device *bl)
duty_cycle = pb->lth_brightness +
(duty_cycle * (pb->period - pb->lth_brightness) / max);
- pwm_config(pb->pwm, duty_cycle, pb->period);
pwm_enable(pb->pwm);
+ pwm_config(pb->pwm, duty_cycle, pb->period);
}
if (pb->notify_after)
More information about the linux-arm-kernel
mailing list