1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright (C) 2016 Free Electrons
  4 *
  5 * Maxime Ripard <maxime.ripard@free-electrons.com>
  6 */
  7
  8#include <linux/clk.h>
  9#include <linux/component.h>
 10#include <linux/module.h>
 11#include <linux/mod_devicetable.h>
 12#include <linux/platform_device.h>
 13#include <linux/regmap.h>
 14#include <linux/reset.h>
 15
 16struct sun6i_drc {
 17	struct clk		*bus_clk;
 18	struct clk		*mod_clk;
 19	struct reset_control	*reset;
 20};
 21
 22static int sun6i_drc_bind(struct device *dev, struct device *master,
 23			 void *data)
 24{
 25	struct sun6i_drc *drc;
 26	int ret;
 27
 28	drc = devm_kzalloc(dev, sizeof(*drc), GFP_KERNEL);
 29	if (!drc)
 30		return -ENOMEM;
 31	dev_set_drvdata(dev, drc);
 32
 33	drc->reset = devm_reset_control_get(dev, NULL);
 34	if (IS_ERR(drc->reset)) {
 35		dev_err(dev, "Couldn't get our reset line\n");
 36		return PTR_ERR(drc->reset);
 37	}
 38
 39	ret = reset_control_deassert(drc->reset);
 40	if (ret) {
 41		dev_err(dev, "Couldn't deassert our reset line\n");
 42		return ret;
 43	}
 44
 45	drc->bus_clk = devm_clk_get(dev, "ahb");
 46	if (IS_ERR(drc->bus_clk)) {
 47		dev_err(dev, "Couldn't get our bus clock\n");
 48		ret = PTR_ERR(drc->bus_clk);
 49		goto err_assert_reset;
 50	}
 51	clk_prepare_enable(drc->bus_clk);
 52
 53	drc->mod_clk = devm_clk_get(dev, "mod");
 54	if (IS_ERR(drc->mod_clk)) {
 55		dev_err(dev, "Couldn't get our mod clock\n");
 56		ret = PTR_ERR(drc->mod_clk);
 57		goto err_disable_bus_clk;
 58	}
 59	clk_prepare_enable(drc->mod_clk);
 60
 61	return 0;
 62
 63err_disable_bus_clk:
 64	clk_disable_unprepare(drc->bus_clk);
 65err_assert_reset:
 66	reset_control_assert(drc->reset);
 67	return ret;
 68}
 69
 70static void sun6i_drc_unbind(struct device *dev, struct device *master,
 71			    void *data)
 72{
 73	struct sun6i_drc *drc = dev_get_drvdata(dev);
 74
 75	clk_disable_unprepare(drc->mod_clk);
 76	clk_disable_unprepare(drc->bus_clk);
 77	reset_control_assert(drc->reset);
 78}
 79
 80static const struct component_ops sun6i_drc_ops = {
 81	.bind	= sun6i_drc_bind,
 82	.unbind	= sun6i_drc_unbind,
 83};
 84
 85static int sun6i_drc_probe(struct platform_device *pdev)
 86{
 87	return component_add(&pdev->dev, &sun6i_drc_ops);
 88}
 89
 90static int sun6i_drc_remove(struct platform_device *pdev)
 91{
 92	component_del(&pdev->dev, &sun6i_drc_ops);
 93
 94	return 0;
 95}
 96
 97static const struct of_device_id sun6i_drc_of_table[] = {
 98	{ .compatible = "allwinner,sun6i-a31-drc" },
 99	{ .compatible = "allwinner,sun6i-a31s-drc" },
100	{ .compatible = "allwinner,sun8i-a23-drc" },
101	{ .compatible = "allwinner,sun8i-a33-drc" },
102	{ .compatible = "allwinner,sun9i-a80-drc" },
103	{ }
104};
105MODULE_DEVICE_TABLE(of, sun6i_drc_of_table);
106
107static struct platform_driver sun6i_drc_platform_driver = {
108	.probe		= sun6i_drc_probe,
109	.remove		= sun6i_drc_remove,
110	.driver		= {
111		.name		= "sun6i-drc",
112		.of_match_table	= sun6i_drc_of_table,
113	},
114};
115module_platform_driver(sun6i_drc_platform_driver);
116
117MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
118MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver");
119MODULE_LICENSE("GPL");