xref: /linux/drivers/bus/tegra-aconnect.c (revision bba2c3615bd6cfee7456d1130f2e6b01b3f4e9ba)
1 /*
2  * Tegra ACONNECT Bus Driver
3  *
4  * Copyright (C) 2016, NVIDIA CORPORATION.  All rights reserved.
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 
11 #include <linux/clk.h>
12 #include <linux/module.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 
17 struct tegra_aconnect {
18 	struct clk	*ape_clk;
19 	struct clk	*apb2ape_clk;
20 };
21 
22 static int tegra_aconnect_probe(struct platform_device *pdev)
23 {
24 	struct tegra_aconnect *aconnect;
25 
26 	if (!pdev->dev.of_node)
27 		return -EINVAL;
28 
29 	aconnect = devm_kzalloc(&pdev->dev, sizeof(struct tegra_aconnect),
30 				GFP_KERNEL);
31 	if (!aconnect)
32 		return -ENOMEM;
33 
34 	aconnect->ape_clk = devm_clk_get(&pdev->dev, "ape");
35 	if (IS_ERR(aconnect->ape_clk))
36 		return dev_err_probe(&pdev->dev, PTR_ERR(aconnect->ape_clk),
37 				     "can't retrieve ape clock\n");
38 
39 	aconnect->apb2ape_clk = devm_clk_get(&pdev->dev, "apb2ape");
40 	if (IS_ERR(aconnect->apb2ape_clk))
41 		return dev_err_probe(&pdev->dev, PTR_ERR(aconnect->apb2ape_clk),
42 				     "can't retrieve apb2ape clock\n");
43 
44 	dev_set_drvdata(&pdev->dev, aconnect);
45 	pm_runtime_enable(&pdev->dev);
46 
47 	of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
48 
49 	dev_info(&pdev->dev, "Tegra ACONNECT bus registered\n");
50 
51 	return 0;
52 }
53 
54 static void tegra_aconnect_remove(struct platform_device *pdev)
55 {
56 	pm_runtime_disable(&pdev->dev);
57 }
58 
59 static int tegra_aconnect_runtime_resume(struct device *dev)
60 {
61 	struct tegra_aconnect *aconnect = dev_get_drvdata(dev);
62 	int ret;
63 
64 	ret = clk_prepare_enable(aconnect->ape_clk);
65 	if (ret) {
66 		dev_err(dev, "ape clk_enable failed: %d\n", ret);
67 		return ret;
68 	}
69 
70 	ret = clk_prepare_enable(aconnect->apb2ape_clk);
71 	if (ret) {
72 		clk_disable_unprepare(aconnect->ape_clk);
73 		dev_err(dev, "apb2ape clk_enable failed: %d\n", ret);
74 		return ret;
75 	}
76 
77 	return 0;
78 }
79 
80 static int tegra_aconnect_runtime_suspend(struct device *dev)
81 {
82 	struct tegra_aconnect *aconnect = dev_get_drvdata(dev);
83 
84 	clk_disable_unprepare(aconnect->ape_clk);
85 	clk_disable_unprepare(aconnect->apb2ape_clk);
86 
87 	return 0;
88 }
89 
90 static const struct dev_pm_ops tegra_aconnect_pm_ops = {
91 	SET_RUNTIME_PM_OPS(tegra_aconnect_runtime_suspend,
92 			   tegra_aconnect_runtime_resume, NULL)
93 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
94 				      pm_runtime_force_resume)
95 };
96 
97 static const struct of_device_id tegra_aconnect_of_match[] = {
98 	{ .compatible = "nvidia,tegra210-aconnect", },
99 	{ }
100 };
101 MODULE_DEVICE_TABLE(of, tegra_aconnect_of_match);
102 
103 static struct platform_driver tegra_aconnect_driver = {
104 	.probe = tegra_aconnect_probe,
105 	.remove = tegra_aconnect_remove,
106 	.driver = {
107 		.name = "tegra-aconnect",
108 		.of_match_table = tegra_aconnect_of_match,
109 		.pm = &tegra_aconnect_pm_ops,
110 	},
111 };
112 module_platform_driver(tegra_aconnect_driver);
113 
114 MODULE_DESCRIPTION("NVIDIA Tegra ACONNECT Bus Driver");
115 MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
116 MODULE_LICENSE("GPL v2");
117