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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2016 Free Electrons
*
* Maxime Ripard <maxime.ripard@free-electrons.com>
*/
#include <linux/clk.h>
#include <linux/component.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
struct sun6i_drc {
struct clk *bus_clk;
struct clk *mod_clk;
struct reset_control *reset;
};
static int sun6i_drc_bind(struct device *dev, struct device *master,
void *data)
{
struct sun6i_drc *drc;
int ret;
drc = devm_kzalloc(dev, sizeof(*drc), GFP_KERNEL);
if (!drc)
return -ENOMEM;
dev_set_drvdata(dev, drc);
drc->reset = devm_reset_control_get(dev, NULL);
if (IS_ERR(drc->reset)) {
dev_err(dev, "Couldn't get our reset line\n");
return PTR_ERR(drc->reset);
}
ret = reset_control_deassert(drc->reset);
if (ret) {
dev_err(dev, "Couldn't deassert our reset line\n");
return ret;
}
drc->bus_clk = devm_clk_get(dev, "ahb");
if (IS_ERR(drc->bus_clk)) {
dev_err(dev, "Couldn't get our bus clock\n");
ret = PTR_ERR(drc->bus_clk);
goto err_assert_reset;
}
clk_prepare_enable(drc->bus_clk);
drc->mod_clk = devm_clk_get(dev, "mod");
if (IS_ERR(drc->mod_clk)) {
dev_err(dev, "Couldn't get our mod clock\n");
ret = PTR_ERR(drc->mod_clk);
goto err_disable_bus_clk;
}
ret = clk_set_rate_exclusive(drc->mod_clk, 300000000);
if (ret) {
dev_err(dev, "Couldn't set the module clock frequency\n");
goto err_disable_bus_clk;
}
clk_prepare_enable(drc->mod_clk);
return 0;
err_disable_bus_clk:
clk_disable_unprepare(drc->bus_clk);
err_assert_reset:
reset_control_assert(drc->reset);
return ret;
}
static void sun6i_drc_unbind(struct device *dev, struct device *master,
void *data)
{
struct sun6i_drc *drc = dev_get_drvdata(dev);
clk_rate_exclusive_put(drc->mod_clk);
clk_disable_unprepare(drc->mod_clk);
clk_disable_unprepare(drc->bus_clk);
reset_control_assert(drc->reset);
}
static const struct component_ops sun6i_drc_ops = {
.bind = sun6i_drc_bind,
.unbind = sun6i_drc_unbind,
};
static int sun6i_drc_probe(struct platform_device *pdev)
{
return component_add(&pdev->dev, &sun6i_drc_ops);
}
static void sun6i_drc_remove(struct platform_device *pdev)
{
component_del(&pdev->dev, &sun6i_drc_ops);
}
static const struct of_device_id sun6i_drc_of_table[] = {
{ .compatible = "allwinner,sun6i-a31-drc" },
{ .compatible = "allwinner,sun6i-a31s-drc" },
{ .compatible = "allwinner,sun8i-a23-drc" },
{ .compatible = "allwinner,sun8i-a33-drc" },
{ .compatible = "allwinner,sun9i-a80-drc" },
{ }
};
MODULE_DEVICE_TABLE(of, sun6i_drc_of_table);
static struct platform_driver sun6i_drc_platform_driver = {
.probe = sun6i_drc_probe,
.remove = sun6i_drc_remove,
.driver = {
.name = "sun6i-drc",
.of_match_table = sun6i_drc_of_table,
},
};
module_platform_driver(sun6i_drc_platform_driver);
MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver");
MODULE_LICENSE("GPL");
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