u-boot/include/clk.h
Simon Glass e70cc43831 dm: clk: Add support for decoding clocks from the device tree
Add a method which can locate a clock for a device, given its index. This
uses the normal device tree bindings to return the clock device and the
first argument which is normally used as a peripheral ID in U-Boot.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-01-21 19:47:29 -07:00

133 lines
3.3 KiB
C

/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef _CLK_H_
#define _CLK_H_
#include <errno.h>
#include <linux/types.h>
struct udevice;
int soc_clk_dump(void);
struct clk_ops {
/**
* get_rate() - Get current clock rate
*
* @dev: Device to check (UCLASS_CLK)
* @return clock rate in Hz, or -ve error code
*/
ulong (*get_rate)(struct udevice *dev);
/**
* set_rate() - Set current clock rate
*
* @dev: Device to adjust
* @rate: New clock rate in Hz
* @return new rate, or -ve error code
*/
ulong (*set_rate)(struct udevice *dev, ulong rate);
/**
* enable() - Enable the clock for a peripheral
*
* @dev: clock provider
* @periph: Peripheral ID to enable
* @return zero on success, or -ve error code
*/
int (*enable)(struct udevice *dev, int periph);
/**
* get_periph_rate() - Get clock rate for a peripheral
*
* @dev: Device to check (UCLASS_CLK)
* @periph: Peripheral ID to check
* @return clock rate in Hz, or -ve error code
*/
ulong (*get_periph_rate)(struct udevice *dev, int periph);
/**
* set_periph_rate() - Set current clock rate for a peripheral
*
* @dev: Device to update (UCLASS_CLK)
* @periph: Peripheral ID to update
* @return new clock rate in Hz, or -ve error code
*/
ulong (*set_periph_rate)(struct udevice *dev, int periph, ulong rate);
};
#define clk_get_ops(dev) ((struct clk_ops *)(dev)->driver->ops)
/**
* clk_get_rate() - Get current clock rate
*
* @dev: Device to check (UCLASS_CLK)
* @return clock rate in Hz, or -ve error code
*/
ulong clk_get_rate(struct udevice *dev);
/**
* clk_set_rate() - Set current clock rate
*
* @dev: Device to adjust
* @rate: New clock rate in Hz
* @return new rate, or -ve error code
*/
ulong clk_set_rate(struct udevice *dev, ulong rate);
/**
* clk_enable() - Enable the clock for a peripheral
*
* @dev: clock provider
* @periph: Peripheral ID to enable
* @return zero on success, or -ve error code
*/
int clk_enable(struct udevice *dev, int periph);
/**
* clk_get_periph_rate() - Get current clock rate for a peripheral
*
* @dev: Device to check (UCLASS_CLK)
* @return clock rate in Hz, -ve error code
*/
ulong clk_get_periph_rate(struct udevice *dev, int periph);
/**
* clk_set_periph_rate() - Set current clock rate for a peripheral
*
* @dev: Device to update (UCLASS_CLK)
* @periph: Peripheral ID to update
* @return new clock rate in Hz, or -ve error code
*/
ulong clk_set_periph_rate(struct udevice *dev, int periph, ulong rate);
#if CONFIG_IS_ENABLED(OF_CONTROL)
/**
* clk_get_by_index() - look up a clock referenced by a device
*
* Parse a device's 'clocks' list, returning information on the indexed clock,
* ensuring that it is activated.
*
* @dev: Device containing the clock reference
* @index: Clock index to return (0 = first)
* @clk_devp: Returns clock device
* @return: Peripheral ID for the device to control. This is the first
* argument after the clock node phandle. If there is no arguemnt,
* returns 0. Return -ve error code on any error
*/
int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp);
#else
static inline int clk_get_by_index(struct udevice *dev, int index,
struct udevice **clk_devp)
{
return -ENOSYS;
}
#endif
#endif /* _CLK_H_ */