1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2016 Free Electrons
4 *
5 * Maxime Ripard <maxime.ripard@free-electrons.com>
6 */
7
8 #include <linux/clk.h>
9 #include <linux/component.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/regmap.h>
13 #include <linux/reset.h>
14
15 struct sun6i_drc {
16 struct clk *bus_clk;
17 struct clk *mod_clk;
18 struct reset_control *reset;
19 };
20
sun6i_drc_bind(struct device * dev,struct device * master,void * data)21 static int sun6i_drc_bind(struct device *dev, struct device *master,
22 void *data)
23 {
24 struct sun6i_drc *drc;
25 int ret;
26
27 drc = devm_kzalloc(dev, sizeof(*drc), GFP_KERNEL);
28 if (!drc)
29 return -ENOMEM;
30 dev_set_drvdata(dev, drc);
31
32 drc->reset = devm_reset_control_get(dev, NULL);
33 if (IS_ERR(drc->reset)) {
34 dev_err(dev, "Couldn't get our reset line\n");
35 return PTR_ERR(drc->reset);
36 }
37
38 ret = reset_control_deassert(drc->reset);
39 if (ret) {
40 dev_err(dev, "Couldn't deassert our reset line\n");
41 return ret;
42 }
43
44 drc->bus_clk = devm_clk_get(dev, "ahb");
45 if (IS_ERR(drc->bus_clk)) {
46 dev_err(dev, "Couldn't get our bus clock\n");
47 ret = PTR_ERR(drc->bus_clk);
48 goto err_assert_reset;
49 }
50 clk_prepare_enable(drc->bus_clk);
51
52 drc->mod_clk = devm_clk_get(dev, "mod");
53 if (IS_ERR(drc->mod_clk)) {
54 dev_err(dev, "Couldn't get our mod clock\n");
55 ret = PTR_ERR(drc->mod_clk);
56 goto err_disable_bus_clk;
57 }
58
59 ret = clk_set_rate_exclusive(drc->mod_clk, 300000000);
60 if (ret) {
61 dev_err(dev, "Couldn't set the module clock frequency\n");
62 goto err_disable_bus_clk;
63 }
64
65 clk_prepare_enable(drc->mod_clk);
66
67 return 0;
68
69 err_disable_bus_clk:
70 clk_disable_unprepare(drc->bus_clk);
71 err_assert_reset:
72 reset_control_assert(drc->reset);
73 return ret;
74 }
75
sun6i_drc_unbind(struct device * dev,struct device * master,void * data)76 static void sun6i_drc_unbind(struct device *dev, struct device *master,
77 void *data)
78 {
79 struct sun6i_drc *drc = dev_get_drvdata(dev);
80
81 clk_rate_exclusive_put(drc->mod_clk);
82 clk_disable_unprepare(drc->mod_clk);
83 clk_disable_unprepare(drc->bus_clk);
84 reset_control_assert(drc->reset);
85 }
86
87 static const struct component_ops sun6i_drc_ops = {
88 .bind = sun6i_drc_bind,
89 .unbind = sun6i_drc_unbind,
90 };
91
sun6i_drc_probe(struct platform_device * pdev)92 static int sun6i_drc_probe(struct platform_device *pdev)
93 {
94 return component_add(&pdev->dev, &sun6i_drc_ops);
95 }
96
sun6i_drc_remove(struct platform_device * pdev)97 static void sun6i_drc_remove(struct platform_device *pdev)
98 {
99 component_del(&pdev->dev, &sun6i_drc_ops);
100 }
101
102 static const struct of_device_id sun6i_drc_of_table[] = {
103 { .compatible = "allwinner,sun6i-a31-drc" },
104 { .compatible = "allwinner,sun6i-a31s-drc" },
105 { .compatible = "allwinner,sun8i-a23-drc" },
106 { .compatible = "allwinner,sun8i-a33-drc" },
107 { .compatible = "allwinner,sun9i-a80-drc" },
108 { }
109 };
110 MODULE_DEVICE_TABLE(of, sun6i_drc_of_table);
111
112 static struct platform_driver sun6i_drc_platform_driver = {
113 .probe = sun6i_drc_probe,
114 .remove = sun6i_drc_remove,
115 .driver = {
116 .name = "sun6i-drc",
117 .of_match_table = sun6i_drc_of_table,
118 },
119 };
120 module_platform_driver(sun6i_drc_platform_driver);
121
122 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
123 MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver");
124 MODULE_LICENSE("GPL");
125