pwm_apply_state() does what the legacy functions pwm_config() and
pwm_{en,dis}able() do in a single function call. This simplifies error
handling and is more efficient for new-style PWM hardware drivers.
Instead of repeatedly querying the PWM framework about the initial PWM
configuration, cache the settings in driver data.
Also use __set_pwm() in .probe() to have the algorithm calculating the PWM
state in a single place.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
On Wed, Dec 30, 2020 at 08:35:20AM -0800, Guenter Roeck wrote:
> Can you rebase this patch on top of hwmon-next ?
Sure, here it is.
Best regards
Uwe
drivers/hwmon/pwm-fan.c | 47 +++++++++++++++++------------------------
1 file changed, 19 insertions(+), 28 deletions(-)
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index b5204aeb8085..41cb829784a2 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -31,6 +31,7 @@ struct pwm_fan_tach {
struct pwm_fan_ctx {
struct mutex lock;
struct pwm_device *pwm;
+ struct pwm_state pwm_state;
struct regulator *reg_en;
int tach_count;
@@ -95,18 +96,17 @@ static int __set_pwm(struct pwm_fan_ctx *ctx, unsigned long pwm)
{
unsigned long period;
int ret = 0;
- struct pwm_state state = { };
+ struct pwm_state *state = &ctx->pwm_state;
mutex_lock(&ctx->lock);
if (ctx->pwm_value == pwm)
goto exit_set_pwm_err;
- pwm_init_state(ctx->pwm, &state);
- period = ctx->pwm->args.period;
- state.duty_cycle = DIV_ROUND_UP(pwm * (period - 1), MAX_PWM);
- state.enabled = pwm ? true : false;
+ period = state->period;
+ state->duty_cycle = DIV_ROUND_UP(pwm * (period - 1), MAX_PWM);
+ state->enabled = pwm ? true : false;
- ret = pwm_apply_state(ctx->pwm, &state);
+ ret = pwm_apply_state(ctx->pwm, state);
if (!ret)
ctx->pwm_value = pwm;
exit_set_pwm_err:
@@ -288,7 +288,9 @@ static void pwm_fan_regulator_disable(void *data)
static void pwm_fan_pwm_disable(void *__ctx)
{
struct pwm_fan_ctx *ctx = __ctx;
- pwm_disable(ctx->pwm);
+
+ ctx->pwm_state.enabled = false;
+ pwm_apply_state(ctx->pwm, &ctx->pwm_state);
del_timer_sync(&ctx->rpm_timer);
}
@@ -299,7 +301,6 @@ static int pwm_fan_probe(struct platform_device *pdev)
struct pwm_fan_ctx *ctx;
struct device *hwmon;
int ret;
- struct pwm_state state = { };
const struct hwmon_channel_info **channels;
u32 *fan_channel_config;
int channel_count = 1; /* We always have a PWM channel. */
@@ -337,22 +338,20 @@ static int pwm_fan_probe(struct platform_device *pdev)
ctx->pwm_value = MAX_PWM;
- pwm_init_state(ctx->pwm, &state);
+ pwm_init_state(ctx->pwm, &ctx->pwm_state);
+
/*
* __set_pwm assumes that MAX_PWM * (period - 1) fits into an unsigned
* long. Check this here to prevent the fan running at a too low
* frequency.
*/
- if (state.period > ULONG_MAX / MAX_PWM + 1) {
+ if (ctx->pwm_state.period > ULONG_MAX / MAX_PWM + 1) {
dev_err(dev, "Configured period too big\n");
return -EINVAL;
}
/* Set duty cycle to maximum allowed and enable PWM output */
- state.duty_cycle = ctx->pwm->args.period - 1;
- state.enabled = true;
-
- ret = pwm_apply_state(ctx->pwm, &state);
+ ret = __set_pwm(ctx, MAX_PWM);
if (ret) {
dev_err(dev, "Failed to configure PWM: %d\n", ret);
return ret;
@@ -468,17 +467,16 @@ static int pwm_fan_probe(struct platform_device *pdev)
static int pwm_fan_disable(struct device *dev)
{
struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
- struct pwm_args args;
int ret;
- pwm_get_args(ctx->pwm, &args);
-
if (ctx->pwm_value) {
- ret = pwm_config(ctx->pwm, 0, args.period);
+ /* keep ctx->pwm_state unmodified for pwm_fan_resume() */
+ struct pwm_state state = ctx->pwm_state;
+ state.duty_cycle = 0;
+ state.enabled = false;
+ ret = pwm_apply_state(ctx->pwm, &state);
if (ret < 0)
return ret;
-
- pwm_disable(ctx->pwm);
}
if (ctx->reg_en) {
@@ -506,8 +504,6 @@ static int pwm_fan_suspend(struct device *dev)
static int pwm_fan_resume(struct device *dev)
{
struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
- struct pwm_args pargs;
- unsigned long duty;
int ret;
if (ctx->reg_en) {
@@ -521,12 +517,7 @@ static int pwm_fan_resume(struct device *dev)
if (ctx->pwm_value == 0)
return 0;
- pwm_get_args(ctx->pwm, &pargs);
- duty = DIV_ROUND_UP_ULL(ctx->pwm_value * (pargs.period - 1), MAX_PWM);
- ret = pwm_config(ctx->pwm, duty, pargs.period);
- if (ret)
- return ret;
- return pwm_enable(ctx->pwm);
+ return pwm_apply_state(ctx->pwm, &ctx->pwm_state);
}
#endif
base-commit: d1f7b079ce5b69c88c813439eea6a9c133f0846b
--
2.29.2
