OpenCloudOS-Kernel/drivers/clk/clk-fixed-rate.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
* Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
*
* 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>
#include <linux/of.h>
#include <linux/platform_device.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;
}
static unsigned long clk_fixed_rate_recalc_accuracy(struct clk_hw *hw,
unsigned long parent_accuracy)
{
struct clk_fixed_rate *fixed = to_clk_fixed_rate(hw);
if (fixed->flags & CLK_FIXED_RATE_PARENT_ACCURACY)
return parent_accuracy;
return fixed->fixed_accuracy;
}
const struct clk_ops clk_fixed_rate_ops = {
.recalc_rate = clk_fixed_rate_recalc_rate,
.recalc_accuracy = clk_fixed_rate_recalc_accuracy,
};
EXPORT_SYMBOL_GPL(clk_fixed_rate_ops);
static void devm_clk_hw_register_fixed_rate_release(struct device *dev, void *res)
{
struct clk_fixed_rate *fix = res;
/*
* We can not use clk_hw_unregister_fixed_rate, since it will kfree()
* the hw, resulting in double free. Just unregister the hw and let
* devres code kfree() it.
*/
clk_hw_unregister(&fix->hw);
}
struct clk_hw *__clk_hw_register_fixed_rate(struct device *dev,
struct device_node *np, const char *name,
const char *parent_name, const struct clk_hw *parent_hw,
const struct clk_parent_data *parent_data, unsigned long flags,
unsigned long fixed_rate, unsigned long fixed_accuracy,
unsigned long clk_fixed_flags, bool devm)
{
struct clk_fixed_rate *fixed;
struct clk_hw *hw;
struct clk_init_data init = {};
int ret = -EINVAL;
/* allocate fixed-rate clock */
if (devm)
fixed = devres_alloc(devm_clk_hw_register_fixed_rate_release,
sizeof(*fixed), GFP_KERNEL);
else
fixed = kzalloc(sizeof(*fixed), GFP_KERNEL);
if (!fixed)
return ERR_PTR(-ENOMEM);
clk: Use a separate struct for holding init data. Create a struct clk_init_data to hold all data that needs to be passed from the platfrom specific driver to the common clock framework during clock registration. Add a pointer to this struct inside clk_hw. This has several advantages: * Completely hides struct clk from many clock platform drivers and static clock initialization code that don't care for static initialization of the struct clks. * For platforms that want to do complete static initialization, it removed the need to directly mess with the struct clk's fields while still allowing to statically allocate struct clk. This keeps the code more future proof even if they include clk-private.h. * Simplifies the generic clk_register() function and allows adding optional fields in the future without modifying the function signature. * Simplifies the static initialization of clocks on all platforms by removing the need for forward delcarations or convoluted macros. Signed-off-by: Saravana Kannan <skannan@codeaurora.org> [mturquette@linaro.org: kept DEFINE_CLK_* macros and __clk_init] Signed-off-by: Mike Turquette <mturquette@linaro.org> Cc: Andrew Lunn <andrew@lunn.ch> Cc: 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>
2012-04-26 13:58:56 +08:00
init.name = name;
init.ops = &clk_fixed_rate_ops;
init.flags = flags;
init.parent_names = parent_name ? &parent_name : NULL;
init.parent_hws = parent_hw ? &parent_hw : NULL;
init.parent_data = parent_data;
if (parent_name || parent_hw || parent_data)
init.num_parents = 1;
else
init.num_parents = 0;
clk: Use a separate struct for holding init data. Create a struct clk_init_data to hold all data that needs to be passed from the platfrom specific driver to the common clock framework during clock registration. Add a pointer to this struct inside clk_hw. This has several advantages: * Completely hides struct clk from many clock platform drivers and static clock initialization code that don't care for static initialization of the struct clks. * For platforms that want to do complete static initialization, it removed the need to directly mess with the struct clk's fields while still allowing to statically allocate struct clk. This keeps the code more future proof even if they include clk-private.h. * Simplifies the generic clk_register() function and allows adding optional fields in the future without modifying the function signature. * Simplifies the static initialization of clocks on all platforms by removing the need for forward delcarations or convoluted macros. Signed-off-by: Saravana Kannan <skannan@codeaurora.org> [mturquette@linaro.org: kept DEFINE_CLK_* macros and __clk_init] Signed-off-by: Mike Turquette <mturquette@linaro.org> Cc: Andrew Lunn <andrew@lunn.ch> Cc: 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>
2012-04-26 13:58:56 +08:00
/* struct clk_fixed_rate assignments */
fixed->flags = clk_fixed_flags;
fixed->fixed_rate = fixed_rate;
fixed->fixed_accuracy = fixed_accuracy;
clk: Use a separate struct for holding init data. Create a struct clk_init_data to hold all data that needs to be passed from the platfrom specific driver to the common clock framework during clock registration. Add a pointer to this struct inside clk_hw. This has several advantages: * Completely hides struct clk from many clock platform drivers and static clock initialization code that don't care for static initialization of the struct clks. * For platforms that want to do complete static initialization, it removed the need to directly mess with the struct clk's fields while still allowing to statically allocate struct clk. This keeps the code more future proof even if they include clk-private.h. * Simplifies the generic clk_register() function and allows adding optional fields in the future without modifying the function signature. * Simplifies the static initialization of clocks on all platforms by removing the need for forward delcarations or convoluted macros. Signed-off-by: Saravana Kannan <skannan@codeaurora.org> [mturquette@linaro.org: kept DEFINE_CLK_* macros and __clk_init] Signed-off-by: Mike Turquette <mturquette@linaro.org> Cc: Andrew Lunn <andrew@lunn.ch> Cc: 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>
2012-04-26 13:58:56 +08:00
fixed->hw.init = &init;
/* register the clock */
hw = &fixed->hw;
if (dev || !np)
ret = clk_hw_register(dev, hw);
else
ret = of_clk_hw_register(np, hw);
if (ret) {
if (devm)
devres_free(fixed);
else
kfree(fixed);
hw = ERR_PTR(ret);
} else if (devm)
devres_add(dev, fixed);
return hw;
}
EXPORT_SYMBOL_GPL(__clk_hw_register_fixed_rate);
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_hw *hw;
hw = clk_hw_register_fixed_rate_with_accuracy(dev, name, parent_name,
flags, fixed_rate, 0);
if (IS_ERR(hw))
return ERR_CAST(hw);
return hw->clk;
}
EXPORT_SYMBOL_GPL(clk_register_fixed_rate);
void clk_unregister_fixed_rate(struct clk *clk)
{
struct clk_hw *hw;
hw = __clk_get_hw(clk);
if (!hw)
return;
clk_unregister(clk);
kfree(to_clk_fixed_rate(hw));
}
EXPORT_SYMBOL_GPL(clk_unregister_fixed_rate);
void clk_hw_unregister_fixed_rate(struct clk_hw *hw)
{
struct clk_fixed_rate *fixed;
fixed = to_clk_fixed_rate(hw);
clk_hw_unregister(hw);
kfree(fixed);
}
EXPORT_SYMBOL_GPL(clk_hw_unregister_fixed_rate);
#ifdef CONFIG_OF
static struct clk_hw *_of_fixed_clk_setup(struct device_node *node)
{
struct clk_hw *hw;
const char *clk_name = node->name;
u32 rate;
u32 accuracy = 0;
int ret;
if (of_property_read_u32(node, "clock-frequency", &rate))
return ERR_PTR(-EIO);
of_property_read_u32(node, "clock-accuracy", &accuracy);
of_property_read_string(node, "clock-output-names", &clk_name);
hw = clk_hw_register_fixed_rate_with_accuracy(NULL, clk_name, NULL,
0, rate, accuracy);
if (IS_ERR(hw))
return hw;
ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw);
if (ret) {
clk_hw_unregister_fixed_rate(hw);
return ERR_PTR(ret);
}
return hw;
}
/**
* of_fixed_clk_setup() - Setup function for simple fixed rate clock
* @node: device node for the clock
*/
void __init of_fixed_clk_setup(struct device_node *node)
{
_of_fixed_clk_setup(node);
}
CLK_OF_DECLARE(fixed_clk, "fixed-clock", of_fixed_clk_setup);
static void of_fixed_clk_remove(struct platform_device *pdev)
{
struct clk_hw *hw = platform_get_drvdata(pdev);
of_clk_del_provider(pdev->dev.of_node);
clk_hw_unregister_fixed_rate(hw);
}
static int of_fixed_clk_probe(struct platform_device *pdev)
{
struct clk_hw *hw;
/*
* This function is not executed when of_fixed_clk_setup
* succeeded.
*/
hw = _of_fixed_clk_setup(pdev->dev.of_node);
if (IS_ERR(hw))
return PTR_ERR(hw);
platform_set_drvdata(pdev, hw);
return 0;
}
static const struct of_device_id of_fixed_clk_ids[] = {
{ .compatible = "fixed-clock" },
{ }
};
static struct platform_driver of_fixed_clk_driver = {
.driver = {
.name = "of_fixed_clk",
.of_match_table = of_fixed_clk_ids,
},
.probe = of_fixed_clk_probe,
.remove_new = of_fixed_clk_remove,
};
builtin_platform_driver(of_fixed_clk_driver);
#endif