f8ce25476d
This is needs to be visible to other architectures using the AMBA bus and peripherals. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
124 lines
3.2 KiB
C
124 lines
3.2 KiB
C
/*
|
|
* linux/include/linux/clk.h
|
|
*
|
|
* Copyright (C) 2004 ARM Limited.
|
|
* Written by Deep Blue Solutions Limited.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#ifndef ASMARM_CLOCK_H
|
|
#define ASMARM_CLOCK_H
|
|
|
|
struct device;
|
|
|
|
/*
|
|
* The base API.
|
|
*/
|
|
|
|
|
|
/*
|
|
* struct clk - an machine class defined object / cookie.
|
|
*/
|
|
struct clk;
|
|
|
|
/**
|
|
* clk_get - lookup and obtain a reference to a clock producer.
|
|
* @dev: device for clock "consumer"
|
|
* @id: clock comsumer ID
|
|
*
|
|
* Returns a struct clk corresponding to the clock producer, or
|
|
* valid IS_ERR() condition containing errno. The implementation
|
|
* uses @dev and @id to determine the clock consumer, and thereby
|
|
* the clock producer. (IOW, @id may be identical strings, but
|
|
* clk_get may return different clock producers depending on @dev.)
|
|
*
|
|
* Drivers must assume that the clock source is not enabled.
|
|
*/
|
|
struct clk *clk_get(struct device *dev, const char *id);
|
|
|
|
/**
|
|
* clk_enable - inform the system when the clock source should be running.
|
|
* @clk: clock source
|
|
*
|
|
* If the clock can not be enabled/disabled, this should return success.
|
|
*
|
|
* Returns success (0) or negative errno.
|
|
*/
|
|
int clk_enable(struct clk *clk);
|
|
|
|
/**
|
|
* clk_disable - inform the system when the clock source is no longer required.
|
|
* @clk: clock source
|
|
*
|
|
* Inform the system that a clock source is no longer required by
|
|
* a driver and may be shut down.
|
|
*
|
|
* Implementation detail: if the clock source is shared between
|
|
* multiple drivers, clk_enable() calls must be balanced by the
|
|
* same number of clk_disable() calls for the clock source to be
|
|
* disabled.
|
|
*/
|
|
void clk_disable(struct clk *clk);
|
|
|
|
/**
|
|
* clk_get_rate - obtain the current clock rate (in Hz) for a clock source.
|
|
* This is only valid once the clock source has been enabled.
|
|
* @clk: clock source
|
|
*/
|
|
unsigned long clk_get_rate(struct clk *clk);
|
|
|
|
/**
|
|
* clk_put - "free" the clock source
|
|
* @clk: clock source
|
|
*
|
|
* Note: drivers must ensure that all clk_enable calls made on this
|
|
* clock source are balanced by clk_disable calls prior to calling
|
|
* this function.
|
|
*/
|
|
void clk_put(struct clk *clk);
|
|
|
|
|
|
/*
|
|
* The remaining APIs are optional for machine class support.
|
|
*/
|
|
|
|
|
|
/**
|
|
* clk_round_rate - adjust a rate to the exact rate a clock can provide
|
|
* @clk: clock source
|
|
* @rate: desired clock rate in Hz
|
|
*
|
|
* Returns rounded clock rate in Hz, or negative errno.
|
|
*/
|
|
long clk_round_rate(struct clk *clk, unsigned long rate);
|
|
|
|
/**
|
|
* clk_set_rate - set the clock rate for a clock source
|
|
* @clk: clock source
|
|
* @rate: desired clock rate in Hz
|
|
*
|
|
* Returns success (0) or negative errno.
|
|
*/
|
|
int clk_set_rate(struct clk *clk, unsigned long rate);
|
|
|
|
/**
|
|
* clk_set_parent - set the parent clock source for this clock
|
|
* @clk: clock source
|
|
* @parent: parent clock source
|
|
*
|
|
* Returns success (0) or negative errno.
|
|
*/
|
|
int clk_set_parent(struct clk *clk, struct clk *parent);
|
|
|
|
/**
|
|
* clk_get_parent - get the parent clock source for this clock
|
|
* @clk: clock source
|
|
*
|
|
* Returns struct clk corresponding to parent clock source, or
|
|
* valid IS_ERR() condition containing errno.
|
|
*/
|
|
struct clk *clk_get_parent(struct clk *clk);
|
|
|
|
#endif
|