Commit 4143804c authored by Stephen Boyd's avatar Stephen Boyd
Browse files

clk: Add {devm_}clk_hw_{register,unregister}() APIs 



We've largely split the clk consumer and provider APIs along
struct clk and struct clk_hw, but clk_register() still returns a
struct clk pointer for each struct clk_hw that's registered.
Eventually we'd like to only allocate struct clks when there's a
user, because struct clk is per-user now, so clk_register() needs
to change.

Let's add new APIs to register struct clk_hws, but this time
we'll hide the struct clk from the caller by returning an int
error code. Also add an unregistration API that takes the clk_hw
structure that was passed to the registration API. This way
provider drivers never have to deal with a struct clk pointer
unless they're using the clk consumer APIs.

Signed-off-by: default avatarStephen Boyd <sboyd@codeaurora.org>
parent a14b9e05

Documentation/driver-model/devres.txt

+1 −0
Original line number Diff line number Diff line
@@ -236,6 +236,7 @@ certainly invest a bit more effort into libata core layer). 
CLOCK

  devm_clk_get()

  devm_clk_put()

  devm_clk_hw_register()



DMA

  dmam_alloc_coherent()

drivers/clk/clk.c

+86 −0
Original line number Diff line number Diff line
@@ -2536,6 +2536,22 @@ fail_out: 
}

EXPORT_SYMBOL_GPL(clk_register);



/**

 * clk_hw_register - register a clk_hw and return an error code

 * @dev: device that is registering this clock

 * @hw: link to hardware-specific clock data

 *

 * clk_hw_register is the primary interface for populating the clock tree with

 * new clock nodes. It returns an integer equal to zero indicating success or

 * less than zero indicating failure. Drivers must test for an error code after

 * calling clk_hw_register().

 */

int clk_hw_register(struct device *dev, struct clk_hw *hw)

{

	return PTR_ERR_OR_ZERO(clk_register(dev, hw));

}

EXPORT_SYMBOL_GPL(clk_hw_register);



/* Free memory allocated for a clock. */

static void __clk_release(struct kref *ref)

{
@@ -2637,11 +2653,26 @@ unlock: 
}

EXPORT_SYMBOL_GPL(clk_unregister);



/**

 * clk_hw_unregister - unregister a currently registered clk_hw

 * @hw: hardware-specific clock data to unregister

 */

void clk_hw_unregister(struct clk_hw *hw)

{

	clk_unregister(hw->clk);

}

EXPORT_SYMBOL_GPL(clk_hw_unregister);



static void devm_clk_release(struct device *dev, void *res)

{

	clk_unregister(*(struct clk **)res);

}



static void devm_clk_hw_release(struct device *dev, void *res)

{

	clk_hw_unregister(*(struct clk_hw **)res);

}



/**

 * devm_clk_register - resource managed clk_register()

 * @dev: device that is registering this clock
@@ -2672,6 +2703,36 @@ struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw) 
}

EXPORT_SYMBOL_GPL(devm_clk_register);



/**

 * devm_clk_hw_register - resource managed clk_hw_register()

 * @dev: device that is registering this clock

 * @hw: link to hardware-specific clock data

 *

 * Managed clk_hw_register(). Clocks returned from this function are

 * automatically clk_hw_unregister()ed on driver detach. See clk_hw_register()

 * for more information.

 */

int devm_clk_hw_register(struct device *dev, struct clk_hw *hw)

{

	struct clk_hw **hwp;

	int ret;



	hwp = devres_alloc(devm_clk_hw_release, sizeof(*hwp), GFP_KERNEL);

	if (!hwp)

		return -ENOMEM;



	ret = clk_hw_register(dev, hw);

	if (!ret) {

		*hwp = hw;

		devres_add(dev, hwp);

	} else {

		devres_free(hwp);

	}



	return ret;

}

EXPORT_SYMBOL_GPL(devm_clk_hw_register);



static int devm_clk_match(struct device *dev, void *res, void *data)

{

	struct clk *c = res;
@@ -2680,6 +2741,15 @@ static int devm_clk_match(struct device *dev, void *res, void *data) 
	return c == data;

}



static int devm_clk_hw_match(struct device *dev, void *res, void *data)

{

	struct clk_hw *hw = res;



	if (WARN_ON(!hw))

		return 0;

	return hw == data;

}



/**

 * devm_clk_unregister - resource managed clk_unregister()

 * @clk: clock to unregister
@@ -2694,6 +2764,22 @@ void devm_clk_unregister(struct device *dev, struct clk *clk) 
}

EXPORT_SYMBOL_GPL(devm_clk_unregister);



/**

 * devm_clk_hw_unregister - resource managed clk_hw_unregister()

 * @dev: device that is unregistering the hardware-specific clock data

 * @hw: link to hardware-specific clock data

 *

 * Unregister a clk_hw registered with devm_clk_hw_register(). Normally

 * this function will not need to be called and the resource management

 * code will ensure that the resource is freed.

 */

void devm_clk_hw_unregister(struct device *dev, struct clk_hw *hw)

{

	WARN_ON(devres_release(dev, devm_clk_hw_release, devm_clk_hw_match,

				hw));

}

EXPORT_SYMBOL_GPL(devm_clk_hw_unregister);



/*

 * clkdev helpers

 */

include/linux/clk-provider.h

+6 −0
Original line number Diff line number Diff line
@@ -655,9 +655,15 @@ struct clk *clk_register_gpio_mux(struct device *dev, const char *name, 
struct clk *clk_register(struct device *dev, struct clk_hw *hw);

struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw);



int __must_check clk_hw_register(struct device *dev, struct clk_hw *hw);

int __must_check devm_clk_hw_register(struct device *dev, struct clk_hw *hw);



void clk_unregister(struct clk *clk);

void devm_clk_unregister(struct device *dev, struct clk *clk);



void clk_hw_unregister(struct clk_hw *hw);

void devm_clk_hw_unregister(struct device *dev, struct clk_hw *hw);



/* helper functions */

const char *__clk_get_name(const struct clk *clk);

const char *clk_hw_get_name(const struct clk_hw *hw);

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