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-provider.h>
19#include <linux/module.h>
20#include <linux/slab.h>
21#include <linux/platform_device.h>
22#include <linux/mfd/rk808.h>
23#include <linux/i2c.h>
24
25#define RK808_NR_OUTPUT 2
26
27struct rk808_clkout {
28	struct rk808 *rk808;
29	struct clk_onecell_data clk_data;
30	struct clk_hw		clkout1_hw;
31	struct clk_hw		clkout2_hw;
32};
33
34static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw,
35					      unsigned long parent_rate)
36{
37	return 32768;
38}
39
40static int rk808_clkout2_enable(struct clk_hw *hw, bool enable)
41{
42	struct rk808_clkout *rk808_clkout = container_of(hw,
43							 struct rk808_clkout,
44							 clkout2_hw);
45	struct rk808 *rk808 = rk808_clkout->rk808;
46
47	return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG,
48				  CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0);
49}
50
51static int rk808_clkout2_prepare(struct clk_hw *hw)
52{
53	return rk808_clkout2_enable(hw, true);
54}
55
56static void rk808_clkout2_unprepare(struct clk_hw *hw)
57{
58	rk808_clkout2_enable(hw, false);
59}
60
61static int rk808_clkout2_is_prepared(struct clk_hw *hw)
62{
63	struct rk808_clkout *rk808_clkout = container_of(hw,
64							 struct rk808_clkout,
65							 clkout2_hw);
66	struct rk808 *rk808 = rk808_clkout->rk808;
67	uint32_t val;
68
69	int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val);
70
71	if (ret < 0)
72		return ret;
73
74	return (val & CLK32KOUT2_EN) ? 1 : 0;
75}
76
77static const struct clk_ops rk808_clkout1_ops = {
78	.recalc_rate = rk808_clkout_recalc_rate,
79};
80
81static const struct clk_ops rk808_clkout2_ops = {
82	.prepare = rk808_clkout2_prepare,
83	.unprepare = rk808_clkout2_unprepare,
84	.is_prepared = rk808_clkout2_is_prepared,
85	.recalc_rate = rk808_clkout_recalc_rate,
86};
87
88static int rk808_clkout_probe(struct platform_device *pdev)
89{
90	struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
91	struct i2c_client *client = rk808->i2c;
92	struct device_node *node = client->dev.of_node;
93	struct clk_init_data init = {};
94	struct clk **clk_table;
95	struct rk808_clkout *rk808_clkout;
96
97	rk808_clkout = devm_kzalloc(&client->dev,
98				    sizeof(*rk808_clkout), GFP_KERNEL);
99	if (!rk808_clkout)
100		return -ENOMEM;
101
102	rk808_clkout->rk808 = rk808;
103
104	clk_table = devm_kcalloc(&client->dev, RK808_NR_OUTPUT,
105				 sizeof(struct clk *), GFP_KERNEL);
106	if (!clk_table)
107		return -ENOMEM;
108
109	init.flags = CLK_IS_ROOT;
110	init.parent_names = NULL;
111	init.num_parents = 0;
112	init.name = "rk808-clkout1";
113	init.ops = &rk808_clkout1_ops;
114	rk808_clkout->clkout1_hw.init = &init;
115
116	/* optional override of the clockname */
117	of_property_read_string_index(node, "clock-output-names",
118				      0, &init.name);
119
120	clk_table[0] = devm_clk_register(&client->dev,
121					 &rk808_clkout->clkout1_hw);
122	if (IS_ERR(clk_table[0]))
123		return PTR_ERR(clk_table[0]);
124
125	init.name = "rk808-clkout2";
126	init.ops = &rk808_clkout2_ops;
127	rk808_clkout->clkout2_hw.init = &init;
128
129	/* optional override of the clockname */
130	of_property_read_string_index(node, "clock-output-names",
131				      1, &init.name);
132
133	clk_table[1] = devm_clk_register(&client->dev,
134					 &rk808_clkout->clkout2_hw);
135	if (IS_ERR(clk_table[1]))
136		return PTR_ERR(clk_table[1]);
137
138	rk808_clkout->clk_data.clks = clk_table;
139	rk808_clkout->clk_data.clk_num = RK808_NR_OUTPUT;
140
141	return of_clk_add_provider(node, of_clk_src_onecell_get,
142				   &rk808_clkout->clk_data);
143}
144
145static int rk808_clkout_remove(struct platform_device *pdev)
146{
147	struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
148	struct i2c_client *client = rk808->i2c;
149	struct device_node *node = client->dev.of_node;
150
151	of_clk_del_provider(node);
152
153	return 0;
154}
155
156static struct platform_driver rk808_clkout_driver = {
157	.probe = rk808_clkout_probe,
158	.remove = rk808_clkout_remove,
159	.driver		= {
160		.name	= "rk808-clkout",
161	},
162};
163
164module_platform_driver(rk808_clkout_driver);
165
166MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs");
167MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
168MODULE_LICENSE("GPL");
169MODULE_ALIAS("platform:rk808-clkout");
170