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/mod_devicetable.h>
16 #include <linux/platform_device.h>
17 #include <linux/regmap.h>
18 #include <linux/reset.h>
19
20 struct sun6i_drc {
21 struct clk *bus_clk;
22 struct clk *mod_clk;
23 struct reset_control *reset;
24 };
25
sun6i_drc_bind(struct device * dev,struct device * master,void * data)26 static int sun6i_drc_bind(struct device *dev, struct device *master,
27 void *data)
28 {
29 struct sun6i_drc *drc;
30 int ret;
31
32 drc = devm_kzalloc(dev, sizeof(*drc), GFP_KERNEL);
33 if (!drc)
34 return -ENOMEM;
35 dev_set_drvdata(dev, drc);
36
37 drc->reset = devm_reset_control_get(dev, NULL);
38 if (IS_ERR(drc->reset)) {
39 dev_err(dev, "Couldn't get our reset line\n");
40 return PTR_ERR(drc->reset);
41 }
42
43 ret = reset_control_deassert(drc->reset);
44 if (ret) {
45 dev_err(dev, "Couldn't deassert our reset line\n");
46 return ret;
47 }
48
49 drc->bus_clk = devm_clk_get(dev, "ahb");
50 if (IS_ERR(drc->bus_clk)) {
51 dev_err(dev, "Couldn't get our bus clock\n");
52 ret = PTR_ERR(drc->bus_clk);
53 goto err_assert_reset;
54 }
55 clk_prepare_enable(drc->bus_clk);
56
57 drc->mod_clk = devm_clk_get(dev, "mod");
58 if (IS_ERR(drc->mod_clk)) {
59 dev_err(dev, "Couldn't get our mod clock\n");
60 ret = PTR_ERR(drc->mod_clk);
61 goto err_disable_bus_clk;
62 }
63 clk_prepare_enable(drc->mod_clk);
64
65 return 0;
66
67 err_disable_bus_clk:
68 clk_disable_unprepare(drc->bus_clk);
69 err_assert_reset:
70 reset_control_assert(drc->reset);
71 return ret;
72 }
73
sun6i_drc_unbind(struct device * dev,struct device * master,void * data)74 static void sun6i_drc_unbind(struct device *dev, struct device *master,
75 void *data)
76 {
77 struct sun6i_drc *drc = dev_get_drvdata(dev);
78
79 clk_disable_unprepare(drc->mod_clk);
80 clk_disable_unprepare(drc->bus_clk);
81 reset_control_assert(drc->reset);
82 }
83
84 static const struct component_ops sun6i_drc_ops = {
85 .bind = sun6i_drc_bind,
86 .unbind = sun6i_drc_unbind,
87 };
88
sun6i_drc_probe(struct platform_device * pdev)89 static int sun6i_drc_probe(struct platform_device *pdev)
90 {
91 return component_add(&pdev->dev, &sun6i_drc_ops);
92 }
93
sun6i_drc_remove(struct platform_device * pdev)94 static int sun6i_drc_remove(struct platform_device *pdev)
95 {
96 component_del(&pdev->dev, &sun6i_drc_ops);
97
98 return 0;
99 }
100
101 static const struct of_device_id sun6i_drc_of_table[] = {
102 { .compatible = "allwinner,sun6i-a31-drc" },
103 { .compatible = "allwinner,sun6i-a31s-drc" },
104 { .compatible = "allwinner,sun8i-a33-drc" },
105 { .compatible = "allwinner,sun9i-a80-drc" },
106 { }
107 };
108 MODULE_DEVICE_TABLE(of, sun6i_drc_of_table);
109
110 static struct platform_driver sun6i_drc_platform_driver = {
111 .probe = sun6i_drc_probe,
112 .remove = sun6i_drc_remove,
113 .driver = {
114 .name = "sun6i-drc",
115 .of_match_table = sun6i_drc_of_table,
116 },
117 };
118 module_platform_driver(sun6i_drc_platform_driver);
119
120 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
121 MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver");
122 MODULE_LICENSE("GPL");
123
