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.red...@avionic-design.de>
Cc: <linux-kernel@vger.kernel.org>
Cc: Sascha Hauer <ker...@pengutronix.de>
Cc: <linux-arm-ker...@lists.infradead.org>
Cc: Dmitry Torokhov <dmitry.torok...@gmail.com>
Cc: <linux-in...@vger.kernel.org>
Cc: Bryan Wu <bryan...@canonical.com>
Cc: Richard Purdie <rpur...@rpsys.net>
Cc: <linux-l...@vger.kernel.org>
Cc: Florian Tobias Schandinat <florianschandi...@gmx.de>
Cc: <linux-fb...@vger.kernel.org>
Cc: Benoît Thébaudeau <benoit.thebaud...@advansee.com>
Signed-off-by: Benoît Thébaudeau <benoit.thebaud...@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)
--
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