9d9f78ed9a
Many platforms support simple gateable clocks, fixed-rate clocks, adjustable divider clocks and multi-parent multiplexer clocks. This patch introduces basic clock types for the above-mentioned hardware which share some common characteristics. Based on original work by Jeremy Kerr and contribution by Jamie Iles. Dividers and multiplexor clocks originally contributed by Richard Zhao & Sascha Hauer. Signed-off-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Mike Turquette <mturquette@ti.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Tested-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Rob Herring <rob.herring@calxeda.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jeremy Kerr <jeremy.kerr@canonical.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergman <arnd.bergmann@linaro.org> Cc: Paul Walmsley <paul@pwsan.com> Cc: Shawn Guo <shawn.guo@freescale.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Jamie Iles <jamie@jamieiles.com> Cc: Richard Zhao <richard.zhao@linaro.org> Cc: Saravana Kannan <skannan@codeaurora.org> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Linus Walleij <linus.walleij@stericsson.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Amit Kucheria <amit.kucheria@linaro.org> Cc: Deepak Saxena <dsaxena@linaro.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
83 lines
2.1 KiB
C
83 lines
2.1 KiB
C
/*
|
|
* Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
|
|
* Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
|
|
*
|
|
* 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.
|
|
*
|
|
* Fixed rate clock implementation
|
|
*/
|
|
|
|
#include <linux/clk-provider.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/io.h>
|
|
#include <linux/err.h>
|
|
|
|
/*
|
|
* DOC: basic fixed-rate clock that cannot gate
|
|
*
|
|
* Traits of this clock:
|
|
* prepare - clk_(un)prepare only ensures parents are prepared
|
|
* enable - clk_enable only ensures parents are enabled
|
|
* rate - rate is always a fixed value. No clk_set_rate support
|
|
* parent - fixed parent. No clk_set_parent support
|
|
*/
|
|
|
|
#define to_clk_fixed_rate(_hw) container_of(_hw, struct clk_fixed_rate, hw)
|
|
|
|
static unsigned long clk_fixed_rate_recalc_rate(struct clk_hw *hw,
|
|
unsigned long parent_rate)
|
|
{
|
|
return to_clk_fixed_rate(hw)->fixed_rate;
|
|
}
|
|
EXPORT_SYMBOL_GPL(clk_fixed_rate_recalc_rate);
|
|
|
|
struct clk_ops clk_fixed_rate_ops = {
|
|
.recalc_rate = clk_fixed_rate_recalc_rate,
|
|
};
|
|
EXPORT_SYMBOL_GPL(clk_fixed_rate_ops);
|
|
|
|
struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
|
|
const char *parent_name, unsigned long flags,
|
|
unsigned long fixed_rate)
|
|
{
|
|
struct clk_fixed_rate *fixed;
|
|
char **parent_names = NULL;
|
|
u8 len;
|
|
|
|
fixed = kzalloc(sizeof(struct clk_fixed_rate), GFP_KERNEL);
|
|
|
|
if (!fixed) {
|
|
pr_err("%s: could not allocate fixed clk\n", __func__);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
/* struct clk_fixed_rate assignments */
|
|
fixed->fixed_rate = fixed_rate;
|
|
|
|
if (parent_name) {
|
|
parent_names = kmalloc(sizeof(char *), GFP_KERNEL);
|
|
|
|
if (! parent_names)
|
|
goto out;
|
|
|
|
len = sizeof(char) * strlen(parent_name);
|
|
|
|
parent_names[0] = kmalloc(len, GFP_KERNEL);
|
|
|
|
if (!parent_names[0])
|
|
goto out;
|
|
|
|
strncpy(parent_names[0], parent_name, len);
|
|
}
|
|
|
|
out:
|
|
return clk_register(dev, name,
|
|
&clk_fixed_rate_ops, &fixed->hw,
|
|
parent_names,
|
|
(parent_name ? 1 : 0),
|
|
flags);
|
|
}
|