xref: /linux/drivers/bus/tegra-aconnect.c (revision 2672031b20f6681514bef14ddcfe8c62c2757d11)
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 		dev_err(&pdev->dev, "Can't retrieve ape clock\n");
37 		return PTR_ERR(aconnect->ape_clk);
38 	}
39 
40 	aconnect->apb2ape_clk = devm_clk_get(&pdev->dev, "apb2ape");
41 	if (IS_ERR(aconnect->apb2ape_clk)) {
42 		dev_err(&pdev->dev, "Can't retrieve apb2ape clock\n");
43 		return PTR_ERR(aconnect->apb2ape_clk);
44 	}
45 
46 	dev_set_drvdata(&pdev->dev, aconnect);
47 	pm_runtime_enable(&pdev->dev);
48 
49 	of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
50 
51 	dev_info(&pdev->dev, "Tegra ACONNECT bus registered\n");
52 
53 	return 0;
54 }
55 
56 static void tegra_aconnect_remove(struct platform_device *pdev)
57 {
58 	pm_runtime_disable(&pdev->dev);
59 }
60 
61 static int tegra_aconnect_runtime_resume(struct device *dev)
62 {
63 	struct tegra_aconnect *aconnect = dev_get_drvdata(dev);
64 	int ret;
65 
66 	ret = clk_prepare_enable(aconnect->ape_clk);
67 	if (ret) {
68 		dev_err(dev, "ape clk_enable failed: %d\n", ret);
69 		return ret;
70 	}
71 
72 	ret = clk_prepare_enable(aconnect->apb2ape_clk);
73 	if (ret) {
74 		clk_disable_unprepare(aconnect->ape_clk);
75 		dev_err(dev, "apb2ape clk_enable failed: %d\n", ret);
76 		return ret;
77 	}
78 
79 	return 0;
80 }
81 
82 static int tegra_aconnect_runtime_suspend(struct device *dev)
83 {
84 	struct tegra_aconnect *aconnect = dev_get_drvdata(dev);
85 
86 	clk_disable_unprepare(aconnect->ape_clk);
87 	clk_disable_unprepare(aconnect->apb2ape_clk);
88 
89 	return 0;
90 }
91 
92 static const struct dev_pm_ops tegra_aconnect_pm_ops = {
93 	SET_RUNTIME_PM_OPS(tegra_aconnect_runtime_suspend,
94 			   tegra_aconnect_runtime_resume, NULL)
95 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
96 				      pm_runtime_force_resume)
97 };
98 
99 static const struct of_device_id tegra_aconnect_of_match[] = {
100 	{ .compatible = "nvidia,tegra210-aconnect", },
101 	{ }
102 };
103 MODULE_DEVICE_TABLE(of, tegra_aconnect_of_match);
104 
105 static struct platform_driver tegra_aconnect_driver = {
106 	.probe = tegra_aconnect_probe,
107 	.remove_new = tegra_aconnect_remove,
108 	.driver = {
109 		.name = "tegra-aconnect",
110 		.of_match_table = tegra_aconnect_of_match,
111 		.pm = &tegra_aconnect_pm_ops,
112 	},
113 };
114 module_platform_driver(tegra_aconnect_driver);
115 
116 MODULE_DESCRIPTION("NVIDIA Tegra ACONNECT Bus Driver");
117 MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
118 MODULE_LICENSE("GPL v2");
119