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path: root/drivers/pwm/core.c
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Diffstat (limited to 'drivers/pwm/core.c')
-rw-r--r--drivers/pwm/core.c100
1 files changed, 85 insertions, 15 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 903138b1884..4b66bf09ee5 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -30,10 +30,9 @@
#include <linux/debugfs.h>
#include <linux/seq_file.h>
-#define MAX_PWMS 1024
+#include <dt-bindings/pwm/pwm.h>
-/* flags in the third cell of the DT PWM specifier */
-#define PWM_SPEC_POLARITY (1 << 0)
+#define MAX_PWMS 1024
static DEFINE_MUTEX(pwm_lookup_lock);
static LIST_HEAD(pwm_lookup_list);
@@ -149,7 +148,7 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args)
pwm_set_period(pwm, args->args[1]);
- if (args->args[2] & PWM_SPEC_POLARITY)
+ if (args->args[2] & PWM_POLARITY_INVERTED)
pwm_set_polarity(pwm, PWM_POLARITY_INVERSED);
else
pwm_set_polarity(pwm, PWM_POLARITY_NORMAL);
@@ -211,6 +210,7 @@ int pwm_set_chip_data(struct pwm_device *pwm, void *data)
return 0;
}
+EXPORT_SYMBOL_GPL(pwm_set_chip_data);
/**
* pwm_get_chip_data() - get private chip data for a PWM
@@ -220,6 +220,7 @@ void *pwm_get_chip_data(struct pwm_device *pwm)
{
return pwm ? pwm->chip_data : NULL;
}
+EXPORT_SYMBOL_GPL(pwm_get_chip_data);
/**
* pwmchip_add() - register a new PWM chip
@@ -272,6 +273,8 @@ int pwmchip_add(struct pwm_chip *chip)
if (IS_ENABLED(CONFIG_OF))
of_pwmchip_add(chip);
+ pwmchip_sysfs_export(chip);
+
out:
mutex_unlock(&pwm_lock);
return ret;
@@ -308,6 +311,8 @@ int pwmchip_remove(struct pwm_chip *chip)
free_pwms(chip);
+ pwmchip_sysfs_unexport(chip);
+
out:
mutex_unlock(&pwm_lock);
return ret;
@@ -400,10 +405,19 @@ EXPORT_SYMBOL_GPL(pwm_free);
*/
int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
{
+ int err;
+
if (!pwm || duty_ns < 0 || period_ns <= 0 || duty_ns > period_ns)
return -EINVAL;
- return pwm->chip->ops->config(pwm->chip, pwm, duty_ns, period_ns);
+ err = pwm->chip->ops->config(pwm->chip, pwm, duty_ns, period_ns);
+ if (err)
+ return err;
+
+ pwm->duty_cycle = duty_ns;
+ pwm->period = period_ns;
+
+ return 0;
}
EXPORT_SYMBOL_GPL(pwm_config);
@@ -416,6 +430,8 @@ EXPORT_SYMBOL_GPL(pwm_config);
*/
int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
{
+ int err;
+
if (!pwm || !pwm->chip->ops)
return -EINVAL;
@@ -425,7 +441,13 @@ int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
if (test_bit(PWMF_ENABLED, &pwm->flags))
return -EBUSY;
- return pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity);
+ err = pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity);
+ if (err)
+ return err;
+
+ pwm->polarity = polarity;
+
+ return 0;
}
EXPORT_SYMBOL_GPL(pwm_set_polarity);
@@ -471,7 +493,7 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np)
}
/**
- * of_pwm_request() - request a PWM via the PWM framework
+ * of_pwm_get() - request a PWM via the PWM framework
* @np: device node to get the PWM from
* @con_id: consumer name
*
@@ -486,8 +508,7 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np)
* becomes mandatory for devices that look up the PWM device via the con_id
* parameter.
*/
-static struct pwm_device *of_pwm_request(struct device_node *np,
- const char *con_id)
+struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
{
struct pwm_device *pwm = NULL;
struct of_phandle_args args;
@@ -545,6 +566,7 @@ put:
return pwm;
}
+EXPORT_SYMBOL_GPL(of_pwm_get);
/**
* pwm_add_table() - register PWM device consumers
@@ -587,7 +609,7 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
/* look up via DT first */
if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
- return of_pwm_request(dev->of_node, con_id);
+ return of_pwm_get(dev->of_node, con_id);
/*
* We look up the provider in the static table typically provided by
@@ -639,10 +661,16 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
}
}
+ mutex_unlock(&pwm_lookup_lock);
+
if (chip)
pwm = pwm_request_from_chip(chip, index, con_id ?: dev_id);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ pwm_set_period(pwm, p->period);
+ pwm_set_polarity(pwm, p->polarity);
- mutex_unlock(&pwm_lookup_lock);
return pwm;
}
@@ -692,7 +720,7 @@ struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id)
{
struct pwm_device **ptr, *pwm;
- ptr = devres_alloc(devm_pwm_release, sizeof(**ptr), GFP_KERNEL);
+ ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
@@ -708,6 +736,36 @@ struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id)
}
EXPORT_SYMBOL_GPL(devm_pwm_get);
+/**
+ * devm_of_pwm_get() - resource managed of_pwm_get()
+ * @dev: device for PWM consumer
+ * @np: device node to get the PWM from
+ * @con_id: consumer name
+ *
+ * This function performs like of_pwm_get() but the acquired PWM device will
+ * automatically be released on driver detach.
+ */
+struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
+ const char *con_id)
+{
+ struct pwm_device **ptr, *pwm;
+
+ ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ pwm = of_pwm_get(np, con_id);
+ if (!IS_ERR(pwm)) {
+ *ptr = pwm;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(devm_of_pwm_get);
+
static int devm_pwm_match(struct device *dev, void *res, void *data)
{
struct pwm_device **p = res;
@@ -733,6 +791,18 @@ void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
}
EXPORT_SYMBOL_GPL(devm_pwm_put);
+/**
+ * pwm_can_sleep() - report whether PWM access will sleep
+ * @pwm: PWM device
+ *
+ * It returns true if accessing the PWM can sleep, false otherwise.
+ */
+bool pwm_can_sleep(struct pwm_device *pwm)
+{
+ return pwm->chip->can_sleep;
+}
+EXPORT_SYMBOL_GPL(pwm_can_sleep);
+
#ifdef CONFIG_DEBUG_FS
static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
{
@@ -744,12 +814,12 @@ static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label);
if (test_bit(PWMF_REQUESTED, &pwm->flags))
- seq_printf(s, " requested");
+ seq_puts(s, " requested");
if (test_bit(PWMF_ENABLED, &pwm->flags))
- seq_printf(s, " enabled");
+ seq_puts(s, " enabled");
- seq_printf(s, "\n");
+ seq_puts(s, "\n");
}
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 17:27:45 +0000