GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / clk / clk-rk808.c
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
27 struct 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
34 static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw,
35                                               unsigned long parent_rate)
36 {
37         return 32768;
38 }
39
40 static 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
51 static int rk808_clkout2_prepare(struct clk_hw *hw)
52 {
53         return rk808_clkout2_enable(hw, true);
54 }
55
56 static void rk808_clkout2_unprepare(struct clk_hw *hw)
57 {
58         rk808_clkout2_enable(hw, false);
59 }
60
61 static 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
77 static const struct clk_ops rk808_clkout1_ops = {
78         .recalc_rate = rk808_clkout_recalc_rate,
79 };
80
81 static 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
88 static 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
145 static 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
156 static 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
164 module_platform_driver(rk808_clkout_driver);
165
166 MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs");
167 MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
168 MODULE_LICENSE("GPL");
169 MODULE_ALIAS("platform:rk808-clkout");