linux-kernel - [PATCH v2 1/3] pwm: pwm-samsung: remove redundant checks from pwm_samsung

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Date:   Mon, 24 Apr 2017 12:01:07 +0200
From:   Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
To:     Thierry Reding <thierry.reding@...il.com>,
        Jean Delvare <jdelvare@...e.com>,
        Guenter Roeck <linux@...ck-us.net>,
        Kamil Debski <kamil@...as.org>
Cc:     Tomasz Figa <tomasz.figa@...il.com>, linux-pwm@...r.kernel.org,
        linux-hwmon@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-samsung-soc@...r.kernel.org, b.zolnierkie@...sung.com
Subject: [PATCH v2 1/3] pwm: pwm-samsung: remove redundant checks from
 pwm_samsung_config()

If the requested period_ns and duty_ns values are identical to
the last programmed ones pwm_samsung_config() returns early and
skips the hardware configuration. The same checks are now done
by the PWM core so the driver specific ones can be removed.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
---
 drivers/pwm/pwm-samsung.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c
index f113cda..9ea7638 100644
--- a/drivers/pwm/pwm-samsung.c
+++ b/drivers/pwm/pwm-samsung.c
@@ -312,9 +312,6 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	if (period_ns > NSEC_PER_SEC)
 		return -ERANGE;
 
-	if (period_ns == chan->period_ns && duty_ns == chan->duty_ns)
-		return 0;
-
 	tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm));
 	oldtcmp = readl(our_chip->base + REG_TCMPB(pwm->hwpwm));
 
-- 
1.9.1