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// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) 2012 ARM Limited
*/
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/vexpress.h>
struct vexpress_osc {
struct regmap *reg;
struct clk_hw hw;
unsigned long rate_min;
unsigned long rate_max;
};
#define to_vexpress_osc(osc) container_of(osc, struct vexpress_osc, hw)
static unsigned long vexpress_osc_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct vexpress_osc *osc = to_vexpress_osc(hw);
u32 rate;
regmap_read(osc->reg, 0, &rate);
return rate;
}
static long vexpress_osc_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
struct vexpress_osc *osc = to_vexpress_osc(hw);
if (osc->rate_min && rate < osc->rate_min)
rate = osc->rate_min;
if (osc->rate_max && rate > osc->rate_max)
rate = osc->rate_max;
return rate;
}
static int vexpress_osc_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct vexpress_osc *osc = to_vexpress_osc(hw);
return regmap_write(osc->reg, 0, rate);
}
static const struct clk_ops vexpress_osc_ops = {
.recalc_rate = vexpress_osc_recalc_rate,
.round_rate = vexpress_osc_round_rate,
.set_rate = vexpress_osc_set_rate,
};
static int vexpress_osc_probe(struct platform_device *pdev)
{
struct clk_init_data init;
struct vexpress_osc *osc;
u32 range[2];
int ret;
osc = devm_kzalloc(&pdev->dev, sizeof(*osc), GFP_KERNEL);
if (!osc)
return -ENOMEM;
osc->reg = devm_regmap_init_vexpress_config(&pdev->dev);
if (IS_ERR(osc->reg))
return PTR_ERR(osc->reg);
if (of_property_read_u32_array(pdev->dev.of_node, "freq-range", range,
ARRAY_SIZE(range)) == 0) {
osc->rate_min = range[0];
osc->rate_max = range[1];
}
if (of_property_read_string(pdev->dev.of_node, "clock-output-names",
&init.name) != 0)
init.name = dev_name(&pdev->dev);
init.ops = &vexpress_osc_ops;
init.flags = 0;
init.num_parents = 0;
osc->hw.init = &init;
ret = devm_clk_hw_register(&pdev->dev, &osc->hw);
if (ret < 0)
return ret;
devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get, &osc->hw);
clk_hw_set_rate_range(&osc->hw, osc->rate_min, osc->rate_max);
dev_dbg(&pdev->dev, "Registered clock '%s'\n", init.name);
return 0;
}
static const struct of_device_id vexpress_osc_of_match[] = {
{ .compatible = "arm,vexpress-osc", },
{}
};
MODULE_DEVICE_TABLE(of, vexpress_osc_of_match);
static struct platform_driver vexpress_osc_driver = {
.driver = {
.name = "vexpress-osc",
.of_match_table = vexpress_osc_of_match,
},
.probe = vexpress_osc_probe,
};
module_platform_driver(vexpress_osc_driver);
MODULE_LICENSE("GPL v2");
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