[PATCH v2 4/4] pwm: sysfs: Utilize an array for polarity strings

From: Andy Shevchenko
Date: Fri Aug 26 2022 - 13:07:20 EST


Code is smaller and looks nicer if we combine polarity strings
into an array.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
v2: added pwm_ prefix to the variable (Uwe), adjusted intendation (Uwe)
drivers/pwm/sysfs.c | 32 ++++++++++++--------------------
1 file changed, 12 insertions(+), 20 deletions(-)

diff --git a/drivers/pwm/sysfs.c b/drivers/pwm/sysfs.c
index 767c4b19afb1..502167e44a3d 100644
--- a/drivers/pwm/sysfs.c
+++ b/drivers/pwm/sysfs.c
@@ -151,27 +151,23 @@ static ssize_t enable_store(struct device *child,
return ret ? : size;
}

+static const char * const pwm_polarity_strings[] = {
+ [PWM_POLARITY_NORMAL] = "normal",
+ [PWM_POLARITY_INVERSED] = "inversed",
+};
+
static ssize_t polarity_show(struct device *child,
struct device_attribute *attr,
char *buf)
{
const struct pwm_device *pwm = child_to_pwm_device(child);
- const char *polarity = "unknown";
struct pwm_state state;

pwm_get_state(pwm, &state);
+ if (state.polarity < 0 || state.polarity >= ARRAY_SIZE(pwm_polarity_strings))
+ return sysfs_emit(buf, "unknown\n");

- switch (state.polarity) {
- case PWM_POLARITY_NORMAL:
- polarity = "normal";
- break;
-
- case PWM_POLARITY_INVERSED:
- polarity = "inversed";
- break;
- }
-
- return sysfs_emit(buf, "%s\n", polarity);
+ return sysfs_emit(buf, "%s\n", pwm_polarity_strings[state.polarity]);
}

static ssize_t polarity_store(struct device *child,
@@ -180,20 +176,16 @@ static ssize_t polarity_store(struct device *child,
{
struct pwm_export *export = child_to_pwm_export(child);
struct pwm_device *pwm = export->pwm;
- enum pwm_polarity polarity;
struct pwm_state state;
int ret;

- if (sysfs_streq(buf, "normal"))
- polarity = PWM_POLARITY_NORMAL;
- else if (sysfs_streq(buf, "inversed"))
- polarity = PWM_POLARITY_INVERSED;
- else
- return -EINVAL;
+ ret = sysfs_match_string(pwm_polarity_strings, buf);
+ if (ret < 0)
+ return ret;

mutex_lock(&export->lock);
pwm_get_state(pwm, &state);
- state.polarity = polarity;
+ state.polarity = ret;
ret = pwm_apply_state(pwm, &state);
mutex_unlock(&export->lock);

--
2.35.1