Commit 0af4d704 authored by Uwe Kleine-König's avatar Uwe Kleine-König Committed by Thierry Reding
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pwm: Delete deprecated functions pwm_request() and pwm_free() 



Since commit 5a7fbe45 ("backlight: pwm_bl: Drop support for legacy PWM
probing") the last user of pwm_request() and pwm_free() is gone. So remove
these functions that were deprecated over 10 years ago in commit
8138d2dd ("pwm: Add table-based lookup for static mappings").

Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
[thierry.reding@gmail.com: clean up a bit after removal]
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 9e4fa80a

Documentation/driver-api/pwm.rst

+5 −8
Original line number Diff line number Diff line
@@ -35,12 +35,9 @@ consumers to providers, as given in the following example:: 
Using PWMs

----------



Legacy users can request a PWM device using pwm_request() and free it

after usage with pwm_free().



New users should use the pwm_get() function and pass to it the consumer

device or a consumer name. pwm_put() is used to free the PWM device. Managed

variants of the getter, devm_pwm_get() and devm_fwnode_pwm_get(), also exist.

Consumers use the pwm_get() function and pass to it the consumer device or a

consumer name. pwm_put() is used to free the PWM device. Managed variants of

the getter, devm_pwm_get() and devm_fwnode_pwm_get(), also exist.



After being requested, a PWM has to be configured using::
@@ -165,8 +162,8 @@ consumers should implement it as described in the "Using PWMs" section. 
Locking

-------



The PWM core list manipulations are protected by a mutex, so pwm_request()

and pwm_free() may not be called from an atomic context. Currently the

The PWM core list manipulations are protected by a mutex, so pwm_get()

and pwm_put() may not be called from an atomic context. Currently the

PWM core does not enforce any locking to pwm_enable(), pwm_disable() and

pwm_config(), so the calling context is currently driver specific. This

is an issue derived from the former barebone API and should be fixed soon.

drivers/pwm/core.c

+2 −56
Original line number Diff line number Diff line
@@ -35,11 +35,6 @@ static LIST_HEAD(pwm_chips); 
static DECLARE_BITMAP(allocated_pwms, MAX_PWMS);

static RADIX_TREE(pwm_tree, GFP_KERNEL);



static struct pwm_device *pwm_to_device(unsigned int pwm)

{

	return radix_tree_lookup(&pwm_tree, pwm);

}



/* Called with pwm_lock held */

static int alloc_pwms(unsigned int count)

{
@@ -369,43 +364,6 @@ int devm_pwmchip_add(struct device *dev, struct pwm_chip *chip) 
}

EXPORT_SYMBOL_GPL(devm_pwmchip_add);



/**

 * pwm_request() - request a PWM device

 * @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)

{

	struct pwm_device *dev;

	int err;



	if (pwm < 0 || pwm >= MAX_PWMS)

		return ERR_PTR(-EINVAL);



	mutex_lock(&pwm_lock);



	dev = pwm_to_device(pwm);

	if (!dev) {

		dev = ERR_PTR(-EPROBE_DEFER);

		goto out;

	}



	err = pwm_device_request(dev, label);

	if (err < 0)

		dev = ERR_PTR(err);



out:

	mutex_unlock(&pwm_lock);



	return dev;

}

EXPORT_SYMBOL_GPL(pwm_request);



/**

 * pwm_request_from_chip() - request a PWM device relative to a PWM chip

 * @chip: PWM chip
@@ -438,18 +396,6 @@ struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, 
}

EXPORT_SYMBOL_GPL(pwm_request_from_chip);



/**

 * pwm_free() - free a PWM device

 * @pwm: PWM device

 *

 * This function is deprecated, use pwm_put() instead.

 */

void pwm_free(struct pwm_device *pwm)

{

	pwm_put(pwm);

}

EXPORT_SYMBOL_GPL(pwm_free);



static void pwm_apply_state_debug(struct pwm_device *pwm,

				  const struct pwm_state *state)

{
@@ -790,7 +736,7 @@ static struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np, 
	dl = pwm_device_link_add(dev, pwm);

	if (IS_ERR(dl)) {

		/* of_xlate ended up calling pwm_request_from_chip() */

		pwm_free(pwm);

		pwm_put(pwm);

		pwm = ERR_CAST(dl);

		goto put;

	}
@@ -1014,7 +960,7 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id) 


	dl = pwm_device_link_add(dev, pwm);

	if (IS_ERR(dl)) {

		pwm_free(pwm);

		pwm_put(pwm);

		return ERR_CAST(dl);

	}

include/linux/pwm.h

+0 −13
Original line number Diff line number Diff line
@@ -309,8 +309,6 @@ struct pwm_chip { 


#if IS_ENABLED(CONFIG_PWM)

/* PWM user APIs */

struct pwm_device *pwm_request(int pwm_id, const char *label);

void pwm_free(struct pwm_device *pwm);

int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state);

int pwm_adjust_config(struct pwm_device *pwm);
@@ -410,17 +408,6 @@ struct pwm_device *devm_fwnode_pwm_get(struct device *dev, 
				       struct fwnode_handle *fwnode,

				       const char *con_id);

#else

static inline struct pwm_device *pwm_request(int pwm_id, const char *label)

{

	might_sleep();

	return ERR_PTR(-ENODEV);

}



static inline void pwm_free(struct pwm_device *pwm)

{

	might_sleep();

}



static inline int pwm_apply_state(struct pwm_device *pwm,

				  const struct pwm_state *state)

{