linux-kernel - [RFC PATCH 3/4] pwm: sun4i: Move delay to function

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 17 Mar 2020 16:59:05 +0100
From:   Pascal Roeleven <dev@...calroeleven.nl>
To:     Thierry Reding <thierry.reding@...il.com>,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>,
        Maxime Ripard <mripard@...nel.org>,
        Chen-Yu Tsai <wens@...e.org>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        linux-pwm@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org
Cc:     linux-sunxi@...glegroups.com,
        Pascal Roeleven <dev@...calroeleven.nl>
Subject: [RFC PATCH 3/4] pwm: sun4i: Move delay to function

Move the delay to a function so we can reuse it.

Signed-off-by: Pascal Roeleven <dev@...calroeleven.nl>
---
 drivers/pwm/pwm-sun4i.c | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
index 56942036b..a11d00f96 100644
--- a/drivers/pwm/pwm-sun4i.c
+++ b/drivers/pwm/pwm-sun4i.c
@@ -89,7 +89,6 @@ struct sun4i_pwm_chip {
 	void __iomem *base;
 	spinlock_t ctrl_lock;
 	const struct sun4i_pwm_data *data;
-	unsigned long next_period[2];
 };
 
 static inline struct sun4i_pwm_chip *to_sun4i_pwm_chip(struct pwm_chip *chip)
@@ -228,6 +227,20 @@ static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4i_pwm,
 	return 0;
 }
 
+static void sun4i_pwm_wait(unsigned long next_period) {
+	unsigned int delay_us;
+	unsigned long now;
+
+	now = jiffies;
+	if (time_before(now, next_period)) {
+		delay_us = jiffies_to_usecs(next_period - now);
+		if ((delay_us / 500) > MAX_UDELAY_MS)
+			msleep(delay_us / 1000 + 1);
+		else
+			usleep_range(delay_us, delay_us * 2);
+	}
+}
+
 static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 			   const struct pwm_state *state)
 {
@@ -235,8 +248,8 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 	struct pwm_state cstate;
 	u32 ctrl, duty = 0, period = 0, val;
 	int ret;
-	unsigned int delay_us, prescaler = 0;
-	unsigned long now;
+	unsigned int prescaler = 0;
+	unsigned long next_period;
 	bool bypass;
 
 	pwm_get_state(pwm, &cstate);
@@ -284,8 +297,7 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 
 	val = (duty & PWM_DTY_MASK) | PWM_PRD(period);
 	sun4i_pwm_writel(sun4i_pwm, val, PWM_CH_PRD(pwm->hwpwm));
-	sun4i_pwm->next_period[pwm->hwpwm] = jiffies +
-		usecs_to_jiffies(cstate.period / 1000 + 1);
+	next_period = jiffies + usecs_to_jiffies(cstate.period / 1000 + 1);
 
 	if (state->polarity != PWM_POLARITY_NORMAL)
 		ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm);
@@ -308,15 +320,7 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 		return 0;
 
 	/* We need a full period to elapse before disabling the channel. */
-	now = jiffies;
-	if (time_before(now, sun4i_pwm->next_period[pwm->hwpwm])) {
-		delay_us = jiffies_to_usecs(sun4i_pwm->next_period[pwm->hwpwm] -
-					   now);
-		if ((delay_us / 500) > MAX_UDELAY_MS)
-			msleep(delay_us / 1000 + 1);
-		else
-			usleep_range(delay_us, delay_us * 2);
-	}
+	sun4i_pwm_wait(next_period);
 
 	spin_lock(&sun4i_pwm->ctrl_lock);
 	ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
-- 
2.20.1