1/*
2 * Clkout driver for Rockchip RK808
3 *
4 * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
5 *
6 * Author:Chris Zhong <zyw@rock-chips.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15 * more details.
16 */
17
18#include <linux/clk.h>
19#include <linux/clk-provider.h>
20#include <linux/module.h>
21#include <linux/slab.h>
22#include <linux/platform_device.h>
23#include <linux/mfd/rk808.h>
24#include <linux/i2c.h>
25
26#define RK808_NR_OUTPUT 2
27
28struct rk808_clkout {
29	struct rk808 *rk808;
30	struct clk_onecell_data clk_data;
31	struct clk_hw		clkout1_hw;
32	struct clk_hw		clkout2_hw;
33};
34
35static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw,
36					      unsigned long parent_rate)
37{
38	return 32768;
39}
40
41static int rk808_clkout2_enable(struct clk_hw *hw, bool enable)
42{
43	struct rk808_clkout *rk808_clkout = container_of(hw,
44							 struct rk808_clkout,
45							 clkout2_hw);
46	struct rk808 *rk808 = rk808_clkout->rk808;
47
48	return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG,
49				  CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0);
50}
51
52static int rk808_clkout2_prepare(struct clk_hw *hw)
53{
54	return rk808_clkout2_enable(hw, true);
55}
56
57static void rk808_clkout2_unprepare(struct clk_hw *hw)
58{
59	rk808_clkout2_enable(hw, false);
60}
61
62static int rk808_clkout2_is_prepared(struct clk_hw *hw)
63{
64	struct rk808_clkout *rk808_clkout = container_of(hw,
65							 struct rk808_clkout,
66							 clkout2_hw);
67	struct rk808 *rk808 = rk808_clkout->rk808;
68	uint32_t val;
69
70	int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val);
71
72	if (ret < 0)
73		return ret;
74
75	return (val & CLK32KOUT2_EN) ? 1 : 0;
76}
77
78static const struct clk_ops rk808_clkout1_ops = {
79	.recalc_rate = rk808_clkout_recalc_rate,
80};
81
82static const struct clk_ops rk808_clkout2_ops = {
83	.prepare = rk808_clkout2_prepare,
84	.unprepare = rk808_clkout2_unprepare,
85	.is_prepared = rk808_clkout2_is_prepared,
86	.recalc_rate = rk808_clkout_recalc_rate,
87};
88
89static int rk808_clkout_probe(struct platform_device *pdev)
90{
91	struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
92	struct i2c_client *client = rk808->i2c;
93	struct device_node *node = client->dev.of_node;
94	struct clk_init_data init = {};
95	struct clk **clk_table;
96	struct rk808_clkout *rk808_clkout;
97
98	rk808_clkout = devm_kzalloc(&client->dev,
99				    sizeof(*rk808_clkout), GFP_KERNEL);
100	if (!rk808_clkout)
101		return -ENOMEM;
102
103	rk808_clkout->rk808 = rk808;
104
105	clk_table = devm_kcalloc(&client->dev, RK808_NR_OUTPUT,
106				 sizeof(struct clk *), GFP_KERNEL);
107	if (!clk_table)
108		return -ENOMEM;
109
110	init.flags = CLK_IS_ROOT;
111	init.parent_names = NULL;
112	init.num_parents = 0;
113	init.name = "rk808-clkout1";
114	init.ops = &rk808_clkout1_ops;
115	rk808_clkout->clkout1_hw.init = &init;
116
117	/* optional override of the clockname */
118	of_property_read_string_index(node, "clock-output-names",
119				      0, &init.name);
120
121	clk_table[0] = devm_clk_register(&client->dev,
122					 &rk808_clkout->clkout1_hw);
123	if (IS_ERR(clk_table[0]))
124		return PTR_ERR(clk_table[0]);
125
126	init.name = "rk808-clkout2";
127	init.ops = &rk808_clkout2_ops;
128	rk808_clkout->clkout2_hw.init = &init;
129
130	/* optional override of the clockname */
131	of_property_read_string_index(node, "clock-output-names",
132				      1, &init.name);
133
134	clk_table[1] = devm_clk_register(&client->dev,
135					 &rk808_clkout->clkout2_hw);
136	if (IS_ERR(clk_table[1]))
137		return PTR_ERR(clk_table[1]);
138
139	rk808_clkout->clk_data.clks = clk_table;
140	rk808_clkout->clk_data.clk_num = RK808_NR_OUTPUT;
141
142	return of_clk_add_provider(node, of_clk_src_onecell_get,
143				   &rk808_clkout->clk_data);
144}
145
146static int rk808_clkout_remove(struct platform_device *pdev)
147{
148	struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
149	struct i2c_client *client = rk808->i2c;
150	struct device_node *node = client->dev.of_node;
151
152	of_clk_del_provider(node);
153
154	return 0;
155}
156
157static struct platform_driver rk808_clkout_driver = {
158	.probe = rk808_clkout_probe,
159	.remove = rk808_clkout_remove,
160	.driver		= {
161		.name	= "rk808-clkout",
162	},
163};
164
165module_platform_driver(rk808_clkout_driver);
166
167MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs");
168MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
169MODULE_LICENSE("GPL");
170MODULE_ALIAS("platform:rk808-clkout");
171