linux-kernel - [PATCH] pwm: rockchip: simplify rockchip_pwm_get

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Message-Id: <20190919091728.24756-1-linux@rasmusvillemoes.dk>
Date:   Thu, 19 Sep 2019 11:17:27 +0200
From:   Rasmus Villemoes <linux@...musvillemoes.dk>
To:     Thierry Reding <thierry.reding@...il.com>,
        Heiko Stuebner <heiko@...ech.de>
Cc:     David Wu <david.wu@...k-chips.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        linux-pwm@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-rockchip@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH] pwm: rockchip: simplify rockchip_pwm_get_state()

The way state->enabled is computed is rather convoluted and hard to
read - both branches of the if() actually do the exact same thing. So
remove the if(), and further simplify "<boolean condition> ? true :
false" to "<boolean condition>".

Signed-off-by: Rasmus Villemoes <linux@...musvillemoes.dk>
---
I stumbled on this while trying to understand how the pwm subsystem
works. This patch is a semantic no-op, but it's also possible that,
say, the first branch simply contains a "double negative" so either
the != should be == or the "false : true" should be "true : false".

 drivers/pwm/pwm-rockchip.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
index 51b96cb7dd25..54c6399e3f00 100644
--- a/drivers/pwm/pwm-rockchip.c
+++ b/drivers/pwm/pwm-rockchip.c
@@ -83,12 +83,7 @@ static void rockchip_pwm_get_state(struct pwm_chip *chip,
 	state->duty_cycle =  DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
 
 	val = readl_relaxed(pc->base + pc->data->regs.ctrl);
-	if (pc->data->supports_polarity)
-		state->enabled = ((val & enable_conf) != enable_conf) ?
-				 false : true;
-	else
-		state->enabled = ((val & enable_conf) == enable_conf) ?
-				 true : false;
+	state->enabled = ((val & enable_conf) == enable_conf);
 
 	if (pc->data->supports_polarity) {
 		if (!(val & PWM_DUTY_POSITIVE))
-- 
2.20.1