drivers/bus/tegra-aconnect.c

   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_clock.h>
  16 #include <linux/pm_runtime.h>
  17
  18 static int tegra_aconnect_add_clock(struct device *dev, char *name)
  19 {
  20         struct clk *clk;
  21         int ret;
  22
  23         clk = clk_get(dev, name);
  24         if (IS_ERR(clk)) {
  25                 dev_err(dev, "%s clock not found\n", name);
  26                 return PTR_ERR(clk);
  27         }
  28
  29         ret = pm_clk_add_clk(dev, clk);
  30         if (ret)
  31                 clk_put(clk);
  32
  33         return ret;
  34 }
  35
  36 static int tegra_aconnect_probe(struct platform_device *pdev)
  37 {
  38         int ret;
  39
  40         if (!pdev->dev.of_node)
  41                 return -EINVAL;
  42
  43         ret = pm_clk_create(&pdev->dev);
  44         if (ret)
  45                 return ret;
  46
  47         ret = tegra_aconnect_add_clock(&pdev->dev, "ape");
  48         if (ret)
  49                 goto clk_destroy;
  50
  51         ret = tegra_aconnect_add_clock(&pdev->dev, "apb2ape");
  52         if (ret)
  53                 goto clk_destroy;
  54
  55         pm_runtime_enable(&pdev->dev);
  56
  57         of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
  58
  59         dev_info(&pdev->dev, "Tegra ACONNECT bus registered\n");
  60
  61         return 0;
  62
  63 clk_destroy:
  64         pm_clk_destroy(&pdev->dev);
  65
  66         return ret;
  67 }
  68
  69 static int tegra_aconnect_remove(struct platform_device *pdev)
  70 {
  71         pm_runtime_disable(&pdev->dev);
  72
  73         pm_clk_destroy(&pdev->dev);
  74
  75         return 0;
  76 }
  77
  78 static int tegra_aconnect_runtime_resume(struct device *dev)
  79 {
  80         return pm_clk_resume(dev);
  81 }
  82
  83 static int tegra_aconnect_runtime_suspend(struct device *dev)
  84 {
  85         return pm_clk_suspend(dev);
  86 }
  87
  88 static const struct dev_pm_ops tegra_aconnect_pm_ops = {
  89         SET_RUNTIME_PM_OPS(tegra_aconnect_runtime_suspend,
  90                            tegra_aconnect_runtime_resume, NULL)
  91 };
  92
  93 static const struct of_device_id tegra_aconnect_of_match[] = {
  94         { .compatible = "nvidia,tegra210-aconnect", },
  95         { }
  96 };
  97 MODULE_DEVICE_TABLE(of, tegra_aconnect_of_match);
  98
  99 static struct platform_driver tegra_aconnect_driver = {
 100         .probe = tegra_aconnect_probe,
 101         .remove = tegra_aconnect_remove,
 102         .driver = {
 103                 .name = "tegra-aconnect",
 104                 .of_match_table = tegra_aconnect_of_match,
 105                 .pm = &tegra_aconnect_pm_ops,
 106         },
 107 };
 108 module_platform_driver(tegra_aconnect_driver);
 109
 110 MODULE_DESCRIPTION("NVIDIA Tegra ACONNECT Bus Driver");
 111 MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
 112 MODULE_LICENSE("GPL v2");