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authorGravatar Linus Torvalds <torvalds@linux-foundation.org> 2015-09-09 10:55:32 -0700
committerGravatar Linus Torvalds <torvalds@linux-foundation.org> 2015-09-09 10:55:32 -0700
commit82278fc079542a04e076da34546a7d6dc649b0cc (patch)
tree96d32ea11f41ee6623190f31f4f6a9263f0c9ddc /drivers/pwm/core.c
parentfix ufs write vs readpage race when writing into a hole (diff)
parentARM: at91: pwm: atmel-hlcdc: Add at91sam9n12 errata (diff)
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Merge tag 'pwm/for-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding: "This set of changes introduces the beginnings of a new API that's based around the concept of states that can be atomically applied. Drivers go to various lengths to implement something similar, which indicates that the core should really be providing the necessary framework. On top of that, there is a bit of cleanup as well as improved kerneldoc and integration into the device-drivers DocBook. Regarding drivers there is a new one for the NXP LPC18xx family of SoCs and a couple of fixes for existing drivers (pca9685, Broadcom Kona and Atmel HLCDC)" * tag 'pwm/for-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: ARM: at91: pwm: atmel-hlcdc: Add at91sam9n12 errata pwm: Add NXP LPC18xx PWM/SCT DT binding documentation pwm: NXP LPC18xx PWM/SCT driver pwm-pca9685: Support changing the output frequency pwm-pca9685: Fix several driver bugs pwm: kona: Modify settings application sequence pwm: pca9685: Drop owner assignment pwm: Add to device-drivers documentation pwm: Clean up kerneldoc pwm: Remove useless whitespace pwm: sysfs: Remove unnecessary padding pwm: sysfs: Properly convert from enum to string pwm: Make use of pwm_get_xxx() helpers where appropriate pwm: Add pwm_get_polarity() helper function pwm: Constify PWM device where possible pwm: Add the pwm_is_enabled() helper
Diffstat (limited to 'drivers/pwm/core.c')
-rw-r--r--drivers/pwm/core.c49
1 files changed, 40 insertions, 9 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 3a7769fe53de..3f9df3ea3350 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -200,6 +200,8 @@ static void of_pwmchip_remove(struct pwm_chip *chip)
* pwm_set_chip_data() - set private chip data for a PWM
* @pwm: PWM device
* @data: pointer to chip-specific data
+ *
+ * Returns: 0 on success or a negative error code on failure.
*/
int pwm_set_chip_data(struct pwm_device *pwm, void *data)
{
@@ -215,6 +217,8 @@ EXPORT_SYMBOL_GPL(pwm_set_chip_data);
/**
* pwm_get_chip_data() - get private chip data for a PWM
* @pwm: PWM device
+ *
+ * Returns: A pointer to the chip-private data for the PWM device.
*/
void *pwm_get_chip_data(struct pwm_device *pwm)
{
@@ -230,6 +234,8 @@ EXPORT_SYMBOL_GPL(pwm_get_chip_data);
* Register a new PWM chip. If chip->base < 0 then a dynamically assigned base
* will be used. The initial polarity for all channels is specified by the
* @polarity parameter.
+ *
+ * Returns: 0 on success or a negative error code on failure.
*/
int pwmchip_add_with_polarity(struct pwm_chip *chip,
enum pwm_polarity polarity)
@@ -291,6 +297,8 @@ EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity);
*
* Register a new PWM chip. If chip->base < 0 then a dynamically assigned base
* will be used. The initial polarity for all channels is normal.
+ *
+ * Returns: 0 on success or a negative error code on failure.
*/
int pwmchip_add(struct pwm_chip *chip)
{
@@ -304,6 +312,8 @@ EXPORT_SYMBOL_GPL(pwmchip_add);
*
* Removes a PWM chip. This function may return busy if the PWM chip provides
* a PWM device that is still requested.
+ *
+ * Returns: 0 on success or a negative error code on failure.
*/
int pwmchip_remove(struct pwm_chip *chip)
{
@@ -338,10 +348,13 @@ EXPORT_SYMBOL_GPL(pwmchip_remove);
/**
* pwm_request() - request a PWM device
- * @pwm_id: global PWM device index
+ * @pwm: global PWM device index
* @label: PWM device label
*
* This function is deprecated, use pwm_get() instead.
+ *
+ * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on
+ * failure.
*/
struct pwm_device *pwm_request(int pwm, const char *label)
{
@@ -376,9 +389,9 @@ EXPORT_SYMBOL_GPL(pwm_request);
* @index: per-chip index of the PWM to request
* @label: a literal description string of this PWM
*
- * Returns the PWM at the given index of the given PWM chip. A negative error
- * code is returned if the index is not valid for the specified PWM chip or
- * if the PWM device cannot be requested.
+ * Returns: A pointer to the PWM device at the given index of the given PWM
+ * chip. A negative error code is returned if the index is not valid for the
+ * specified PWM chip or if the PWM device cannot be requested.
*/
struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip,
unsigned int index,
@@ -419,6 +432,8 @@ EXPORT_SYMBOL_GPL(pwm_free);
* @pwm: PWM device
* @duty_ns: "on" time (in nanoseconds)
* @period_ns: duration (in nanoseconds) of one cycle
+ *
+ * Returns: 0 on success or a negative error code on failure.
*/
int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
{
@@ -443,7 +458,10 @@ EXPORT_SYMBOL_GPL(pwm_config);
* @pwm: PWM device
* @polarity: new polarity of the PWM signal
*
- * Note that the polarity cannot be configured while the PWM device is enabled
+ * Note that the polarity cannot be configured while the PWM device is
+ * enabled.
+ *
+ * Returns: 0 on success or a negative error code on failure.
*/
int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
{
@@ -455,7 +473,7 @@ int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
if (!pwm->chip->ops->set_polarity)
return -ENOSYS;
- if (test_bit(PWMF_ENABLED, &pwm->flags))
+ if (pwm_is_enabled(pwm))
return -EBUSY;
err = pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity);
@@ -471,6 +489,8 @@ EXPORT_SYMBOL_GPL(pwm_set_polarity);
/**
* pwm_enable() - start a PWM output toggling
* @pwm: PWM device
+ *
+ * Returns: 0 on success or a negative error code on failure.
*/
int pwm_enable(struct pwm_device *pwm)
{
@@ -524,6 +544,9 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np)
* lookup of the PWM index. This also means that the "pwm-names" property
* becomes mandatory for devices that look up the PWM device via the con_id
* parameter.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
*/
struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
{
@@ -630,6 +653,9 @@ void pwm_remove_table(struct pwm_lookup *table, size_t num)
*
* Once a PWM chip has been found the specified PWM device will be requested
* and is ready to be used.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
*/
struct pwm_device *pwm_get(struct device *dev, const char *con_id)
{
@@ -752,6 +778,9 @@ static void devm_pwm_release(struct device *dev, void *res)
*
* This function performs like pwm_get() but the acquired PWM device will
* automatically be released on driver detach.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
*/
struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id)
{
@@ -781,6 +810,9 @@ EXPORT_SYMBOL_GPL(devm_pwm_get);
*
* This function performs like of_pwm_get() but the acquired PWM device will
* automatically be released on driver detach.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
*/
struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
const char *con_id)
@@ -832,7 +864,7 @@ 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.
+ * Returns: True if accessing the PWM can sleep, false otherwise.
*/
bool pwm_can_sleep(struct pwm_device *pwm)
{
@@ -853,7 +885,7 @@ static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
if (test_bit(PWMF_REQUESTED, &pwm->flags))
seq_puts(s, " requested");
- if (test_bit(PWMF_ENABLED, &pwm->flags))
+ if (pwm_is_enabled(pwm))
seq_puts(s, " enabled");
seq_puts(s, "\n");
@@ -924,6 +956,5 @@ static int __init pwm_debugfs_init(void)
return 0;
}
-
subsys_initcall(pwm_debugfs_init);
#endif /* CONFIG_DEBUG_FS */