[<prev] [next>] [day] [month] [year] [list]
Message-Id: <8822fc43463039744581398be844f4417f62abcd.1584650604.git.gurus@codeaurora.org>
Date: Thu, 19 Mar 2020 13:50:07 -0700
From: Guru Das Srinagesh <gurus@...eaurora.org>
To: linux-pwm@...r.kernel.org
Cc: Thierry Reding <thierry.reding@...il.com>,
Uwe Kleine-König <uwe@...ine-koenig.org>,
Subbaraman Narayanamurthy <subbaram@...eaurora.org>,
linux-kernel@...r.kernel.org,
Guru Das Srinagesh <gurus@...eaurora.org>,
Alexander Shiyan <shc_work@...l.ru>,
Arnd Bergmann <arnd@...db.de>
Subject: [PATCH v10 04/12] pwm: clps711x: Cast period to u32 before use as divisor
Since the PWM framework is switching struct pwm_args.period's datatype
to u64, prepare for this transition by typecasting it to u32.
Also, since the dividend is still a 32-bit number, any divisor greater
than UINT_MAX will cause the quotient to be zero, so return 0 in that
case to efficiently skip the division.
Cc: Alexander Shiyan <shc_work@...l.ru>
Cc: Arnd Bergmann <arnd@...db.de>
Signed-off-by: Guru Das Srinagesh <gurus@...eaurora.org>
---
drivers/pwm/pwm-clps711x.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/pwm/pwm-clps711x.c b/drivers/pwm/pwm-clps711x.c
index 924d39a..f34f1f3 100644
--- a/drivers/pwm/pwm-clps711x.c
+++ b/drivers/pwm/pwm-clps711x.c
@@ -43,7 +43,10 @@ static void clps711x_pwm_update_val(struct clps711x_chip *priv, u32 n, u32 v)
static unsigned int clps711x_get_duty(struct pwm_device *pwm, unsigned int v)
{
/* Duty cycle 0..15 max */
- return DIV_ROUND_CLOSEST(v * 0xf, pwm->args.period);
+ if (pwm->args.period > UINT_MAX)
+ return 0;
+
+ return DIV_ROUND_CLOSEST(v * 0xf, (u32)pwm->args.period);
}
static int clps711x_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
Powered by blists - more mailing lists