1/*
  2 * Copyright (C) 2016 Free Electrons
  3 *
  4 * Maxime Ripard <maxime.ripard@free-electrons.com>
  5 *
  6 * This program is free software; you can redistribute it and/or
  7 * modify it under the terms of the GNU General Public License as
  8 * published by the Free Software Foundation; either version 2 of
  9 * the License, or (at your option) any later version.
 10 */
 11
 12#include <linux/clk.h>
 13#include <linux/component.h>
 14#include <linux/module.h>
 15#include <linux/platform_device.h>
 16#include <linux/regmap.h>
 17#include <linux/reset.h>
 18
 19struct sun6i_drc {
 20	struct clk		*bus_clk;
 21	struct clk		*mod_clk;
 22	struct reset_control	*reset;
 23};
 24
 25static int sun6i_drc_bind(struct device *dev, struct device *master,
 26			 void *data)
 27{
 28	struct sun6i_drc *drc;
 29	int ret;
 30
 31	drc = devm_kzalloc(dev, sizeof(*drc), GFP_KERNEL);
 32	if (!drc)
 33		return -ENOMEM;
 34	dev_set_drvdata(dev, drc);
 35
 36	drc->reset = devm_reset_control_get(dev, NULL);
 37	if (IS_ERR(drc->reset)) {
 38		dev_err(dev, "Couldn't get our reset line\n");
 39		return PTR_ERR(drc->reset);
 40	}
 41
 42	ret = reset_control_deassert(drc->reset);
 43	if (ret) {
 44		dev_err(dev, "Couldn't deassert our reset line\n");
 45		return ret;
 46	}
 47
 48	drc->bus_clk = devm_clk_get(dev, "ahb");
 49	if (IS_ERR(drc->bus_clk)) {
 50		dev_err(dev, "Couldn't get our bus clock\n");
 51		ret = PTR_ERR(drc->bus_clk);
 52		goto err_assert_reset;
 53	}
 54	clk_prepare_enable(drc->bus_clk);
 55
 56	drc->mod_clk = devm_clk_get(dev, "mod");
 57	if (IS_ERR(drc->mod_clk)) {
 58		dev_err(dev, "Couldn't get our mod clock\n");
 59		ret = PTR_ERR(drc->mod_clk);
 60		goto err_disable_bus_clk;
 61	}
 62	clk_prepare_enable(drc->mod_clk);
 63
 64	return 0;
 65
 66err_disable_bus_clk:
 67	clk_disable_unprepare(drc->bus_clk);
 68err_assert_reset:
 69	reset_control_assert(drc->reset);
 70	return ret;
 71}
 72
 73static void sun6i_drc_unbind(struct device *dev, struct device *master,
 74			    void *data)
 75{
 76	struct sun6i_drc *drc = dev_get_drvdata(dev);
 77
 78	clk_disable_unprepare(drc->mod_clk);
 79	clk_disable_unprepare(drc->bus_clk);
 80	reset_control_assert(drc->reset);
 81}
 82
 83static const struct component_ops sun6i_drc_ops = {
 84	.bind	= sun6i_drc_bind,
 85	.unbind	= sun6i_drc_unbind,
 86};
 87
 88static int sun6i_drc_probe(struct platform_device *pdev)
 89{
 90	return component_add(&pdev->dev, &sun6i_drc_ops);
 91}
 92
 93static int sun6i_drc_remove(struct platform_device *pdev)
 94{
 95	component_del(&pdev->dev, &sun6i_drc_ops);
 96
 97	return 0;
 98}
 99
100static const struct of_device_id sun6i_drc_of_table[] = {
101	{ .compatible = "allwinner,sun6i-a31-drc" },
102	{ .compatible = "allwinner,sun6i-a31s-drc" },
103	{ .compatible = "allwinner,sun8i-a33-drc" },
104	{ }
105};
106MODULE_DEVICE_TABLE(of, sun6i_drc_of_table);
107
108static struct platform_driver sun6i_drc_platform_driver = {
109	.probe		= sun6i_drc_probe,
110	.remove		= sun6i_drc_remove,
111	.driver		= {
112		.name		= "sun6i-drc",
113		.of_match_table	= sun6i_drc_of_table,
114	},
115};
116module_platform_driver(sun6i_drc_platform_driver);
117
118MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
119MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver");
120MODULE_LICENSE("GPL");