# \[RFC PATCH 02/15\] pwm: fix pwm\_get\_period and pwm\_get\_duty\_cycle prototypes

- From: Boris Brezillon \<hidden\>
- Date: 2015-07-01 08:21:48 
- List: linux-arm-kernel
- Page: https://ratatoskr.run/linux-arm-kernel/2015/07/8716020
- Thread: https://ratatoskr.run/linux-arm-kernel/2015/07/8716021/t.md

```text
The pwm argument is not modified in pwm_get helpers, make it a const
argument so that they can be used from the sysfs functions.

Signed-off-by: Boris Brezillon <redacted>
---
 include/linux/pwm.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index ec34f4d..d8f6913 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -103,7 +103,7 @@ static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period)
 		pwm->period = period;
 }
 
-static inline unsigned int pwm_get_period(struct pwm_device *pwm)
+static inline unsigned int pwm_get_period(const struct pwm_device *pwm)
 {
 	return pwm ? pwm->period : 0;
 }
@@ -114,7 +114,7 @@ static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty)
 		pwm->duty_cycle = duty;
 }
 
-static inline unsigned int pwm_get_duty_cycle(struct pwm_device *pwm)
+static inline unsigned int pwm_get_duty_cycle(const struct pwm_device *pwm)
 {
 	return pwm ? pwm->duty_cycle : 0;
 }
-- 
1.9.1
```