linux-kernel - [PATCH] pwm: bcm-iproc: handle clk_get

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Date:   Fri, 17 Jul 2020 10:07:43 -0700
From:   Scott Branden <scott.branden@...adcom.com>
To:     Thierry Reding <thierry.reding@...il.com>,
        Lee Jones <lee.jones@...aro.org>
Cc:     Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>,
        BCM Kernel Feedback <bcm-kernel-feedback-list@...adcom.com>,
        linux-pwm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Rayagonda Kokatanur <rayagonda.kokatanur@...adcom.com>,
        Scott Branden <scott.branden@...adcom.com>
Subject: [PATCH] pwm: bcm-iproc: handle clk_get_rate() return

From: Rayagonda Kokatanur <rayagonda.kokatanur@...adcom.com>

Handle clk_get_rate() returning <= 0 condition to avoid
possible division by zero.

Fixes: daa5abc41c80 ("pwm: Add support for Broadcom iProc PWM controller")
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@...adcom.com>
Signed-off-by: Scott Branden <scott.branden@...adcom.com>
---
 drivers/pwm/pwm-bcm-iproc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/pwm/pwm-bcm-iproc.c b/drivers/pwm/pwm-bcm-iproc.c
index 1f829edd8ee7..72a8607b6c8d 100644
--- a/drivers/pwm/pwm-bcm-iproc.c
+++ b/drivers/pwm/pwm-bcm-iproc.c
@@ -86,6 +86,11 @@ static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 	u32 value, prescale;
 
 	rate = clk_get_rate(ip->clk);
+	if (rate == 0) {
+		state->period = 0;
+		state->duty_cycle = 0;
+		return;
+	}
 
 	value = readl(ip->base + IPROC_PWM_CTRL_OFFSET);
 
-- 
2.17.1