u-boot/include/clk-uclass.h
Dario Binacchi 2983ad55a1 clk: add clk_round_rate()
It returns the rate which will be set if you ask clk_set_rate() to set
that rate. It provides a way to query exactly what rate you'll get if
you call clk_set_rate() with that same argument.
So essentially, clk_round_rate() and clk_set_rate() are equivalent
except the former does not modify the clock hardware in any way.

Signed-off-by: Dario Binacchi <dariobin@libero.it>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
2021-01-12 10:58:04 +05:30

112 lines
3.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
* Copyright (c) 2016, NVIDIA CORPORATION.
*/
#ifndef _CLK_UCLASS_H
#define _CLK_UCLASS_H
/* See clk.h for background documentation. */
#include <clk.h>
struct ofnode_phandle_args;
/**
* struct clk_ops - The functions that a clock driver must implement.
*/
struct clk_ops {
/**
* of_xlate - Translate a client's device-tree (OF) clock specifier.
*
* The clock core calls this function as the first step in implementing
* a client's clk_get_by_*() call.
*
* If this function pointer is set to NULL, the clock core will use a
* default implementation, which assumes #clock-cells = <1>, and that
* the DT cell contains a simple integer clock ID.
*
* At present, the clock API solely supports device-tree. If this
* changes, other xxx_xlate() functions may be added to support those
* other mechanisms.
*
* @clock: The clock struct to hold the translation result.
* @args: The clock specifier values from device tree.
* @return 0 if OK, or a negative error code.
*/
int (*of_xlate)(struct clk *clock,
struct ofnode_phandle_args *args);
/**
* request - Request a translated clock.
*
* The clock core calls this function as the second step in
* implementing a client's clk_get_by_*() call, following a successful
* xxx_xlate() call, or as the only step in implementing a client's
* clk_request() call.
*
* @clock: The clock struct to request; this has been fille in by
* a previoux xxx_xlate() function call, or by the caller
* of clk_request().
* @return 0 if OK, or a negative error code.
*/
int (*request)(struct clk *clock);
/**
* rfree - Free a previously requested clock.
*
* This is the implementation of the client clk_free() API.
*
* @clock: The clock to free.
* @return 0 if OK, or a negative error code.
*/
int (*rfree)(struct clk *clock);
/**
* round_rate() - Adjust a rate to the exact rate a clock can provide.
*
* @clk: The clock to manipulate.
* @rate: Desidered clock rate in Hz.
* @return rounded rate in Hz, or -ve error code.
*/
ulong (*round_rate)(struct clk *clk, ulong rate);
/**
* get_rate() - Get current clock rate.
*
* @clk: The clock to query.
* @return clock rate in Hz, or -ve error code
*/
ulong (*get_rate)(struct clk *clk);
/**
* set_rate() - Set current clock rate.
*
* @clk: The clock to manipulate.
* @rate: New clock rate in Hz.
* @return new rate, or -ve error code.
*/
ulong (*set_rate)(struct clk *clk, ulong rate);
/**
* set_parent() - Set current clock parent
*
* @clk: The clock to manipulate.
* @parent: New clock parent.
* @return zero on success, or -ve error code.
*/
int (*set_parent)(struct clk *clk, struct clk *parent);
/**
* enable() - Enable a clock.
*
* @clk: The clock to manipulate.
* @return zero on success, or -ve error code.
*/
int (*enable)(struct clk *clk);
/**
* disable() - Disable a clock.
*
* @clk: The clock to manipulate.
* @return zero on success, or -ve error code.
*/
int (*disable)(struct clk *clk);
};
#endif