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
25struct rk808_clkout {
26 struct rk808 *rk808;
27 struct clk_hw clkout1_hw;
28 struct clk_hw clkout2_hw;
29};
30
31static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw,
32 unsigned long parent_rate)
33{
34 return 32768;
35}
36
37static int rk808_clkout2_enable(struct clk_hw *hw, bool enable)
38{
39 struct rk808_clkout *rk808_clkout = container_of(hw,
40 struct rk808_clkout,
41 clkout2_hw);
42 struct rk808 *rk808 = rk808_clkout->rk808;
43
44 return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG,
45 CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0);
46}
47
48static int rk808_clkout2_prepare(struct clk_hw *hw)
49{
50 return rk808_clkout2_enable(hw, true);
51}
52
53static void rk808_clkout2_unprepare(struct clk_hw *hw)
54{
55 rk808_clkout2_enable(hw, false);
56}
57
58static int rk808_clkout2_is_prepared(struct clk_hw *hw)
59{
60 struct rk808_clkout *rk808_clkout = container_of(hw,
61 struct rk808_clkout,
62 clkout2_hw);
63 struct rk808 *rk808 = rk808_clkout->rk808;
64 uint32_t val;
65
66 int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val);
67
68 if (ret < 0)
69 return ret;
70
71 return (val & CLK32KOUT2_EN) ? 1 : 0;
72}
73
74static const struct clk_ops rk808_clkout1_ops = {
75 .recalc_rate = rk808_clkout_recalc_rate,
76};
77
78static const struct clk_ops rk808_clkout2_ops = {
79 .prepare = rk808_clkout2_prepare,
80 .unprepare = rk808_clkout2_unprepare,
81 .is_prepared = rk808_clkout2_is_prepared,
82 .recalc_rate = rk808_clkout_recalc_rate,
83};
84
85static struct clk_hw *
86of_clk_rk808_get(struct of_phandle_args *clkspec, void *data)
87{
88 struct rk808_clkout *rk808_clkout = data;
89 unsigned int idx = clkspec->args[0];
90
91 if (idx >= 2) {
92 pr_err("%s: invalid index %u\n", __func__, idx);
93 return ERR_PTR(-EINVAL);
94 }
95
96 return idx ? &rk808_clkout->clkout2_hw : &rk808_clkout->clkout1_hw;
97}
98
99static int rk808_clkout_probe(struct platform_device *pdev)
100{
101 struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
102 struct i2c_client *client = rk808->i2c;
103 struct device_node *node = client->dev.of_node;
104 struct clk_init_data init = {};
105 struct rk808_clkout *rk808_clkout;
106 int ret;
107
108 rk808_clkout = devm_kzalloc(&client->dev,
109 sizeof(*rk808_clkout), GFP_KERNEL);
110 if (!rk808_clkout)
111 return -ENOMEM;
112
113 rk808_clkout->rk808 = rk808;
114
115 init.parent_names = NULL;
116 init.num_parents = 0;
117 init.name = "rk808-clkout1";
118 init.ops = &rk808_clkout1_ops;
119 rk808_clkout->clkout1_hw.init = &init;
120
121 /* optional override of the clockname */
122 of_property_read_string_index(node, "clock-output-names",
123 0, &init.name);
124
125 ret = devm_clk_hw_register(&client->dev, &rk808_clkout->clkout1_hw);
126 if (ret)
127 return ret;
128
129 init.name = "rk808-clkout2";
130 init.ops = &rk808_clkout2_ops;
131 rk808_clkout->clkout2_hw.init = &init;
132
133 /* optional override of the clockname */
134 of_property_read_string_index(node, "clock-output-names",
135 1, &init.name);
136
137 ret = devm_clk_hw_register(&client->dev, &rk808_clkout->clkout2_hw);
138 if (ret)
139 return ret;
140
141 return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_rk808_get,
142 rk808_clkout);
143}
144
145static struct platform_driver rk808_clkout_driver = {
146 .probe = rk808_clkout_probe,
147 .driver = {
148 .name = "rk808-clkout",
149 },
150};
151
152module_platform_driver(rk808_clkout_driver);
153
154MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs");
155MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
156MODULE_LICENSE("GPL");
157MODULE_ALIAS("platform:rk808-clkout");
158