kernel/drivers/usb/dwc3/dwc3-qcom.c

   1 /* Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 and
   5  * only version 2 as published by the Free Software Foundation.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  */
  12
  13 #include <linux/clk.h>
  14 #include <linux/err.h>
  15 #include <linux/io.h>
  16 #include <linux/module.h>
  17 #include <linux/of.h>
  18 #include <linux/of_platform.h>
  19 #include <linux/platform_device.h>
  20
  21 struct dwc3_qcom {
  22         struct device           *dev;
  23
  24         struct clk              *core_clk;
  25         struct clk              *iface_clk;
  26         struct clk              *sleep_clk;
  27 };
  28
  29 static int dwc3_qcom_probe(struct platform_device *pdev)
  30 {
  31         struct device_node *node = pdev->dev.of_node;
  32         struct dwc3_qcom *qdwc;
  33         int ret;
  34
  35         qdwc = devm_kzalloc(&pdev->dev, sizeof(*qdwc), GFP_KERNEL);
  36         if (!qdwc)
  37                 return -ENOMEM;
  38
  39         platform_set_drvdata(pdev, qdwc);
  40
  41         qdwc->dev = &pdev->dev;
  42
  43         qdwc->core_clk = devm_clk_get(qdwc->dev, "core");
  44         if (IS_ERR(qdwc->core_clk)) {
  45                 dev_err(qdwc->dev, "failed to get core clock\n");
  46                 return PTR_ERR(qdwc->core_clk);
  47         }
  48
  49         qdwc->iface_clk = devm_clk_get(qdwc->dev, "iface");
  50         if (IS_ERR(qdwc->iface_clk)) {
  51                 dev_dbg(qdwc->dev, "failed to get optional iface clock\n");
  52                 qdwc->iface_clk = NULL;
  53         }
  54
  55         qdwc->sleep_clk = devm_clk_get(qdwc->dev, "sleep");
  56         if (IS_ERR(qdwc->sleep_clk)) {
  57                 dev_dbg(qdwc->dev, "failed to get optional sleep clock\n");
  58                 qdwc->sleep_clk = NULL;
  59         }
  60
  61         ret = clk_prepare_enable(qdwc->core_clk);
  62         if (ret) {
  63                 dev_err(qdwc->dev, "failed to enable core clock\n");
  64                 goto err_core;
  65         }
  66
  67         ret = clk_prepare_enable(qdwc->iface_clk);
  68         if (ret) {
  69                 dev_err(qdwc->dev, "failed to enable optional iface clock\n");
  70                 goto err_iface;
  71         }
  72
  73         ret = clk_prepare_enable(qdwc->sleep_clk);
  74         if (ret) {
  75                 dev_err(qdwc->dev, "failed to enable optional sleep clock\n");
  76                 goto err_sleep;
  77         }
  78
  79         ret = of_platform_populate(node, NULL, NULL, qdwc->dev);
  80         if (ret) {
  81                 dev_err(qdwc->dev, "failed to register core - %d\n", ret);
  82                 goto err_clks;
  83         }
  84
  85         return 0;
  86
  87 err_clks:
  88         clk_disable_unprepare(qdwc->sleep_clk);
  89 err_sleep:
  90         clk_disable_unprepare(qdwc->iface_clk);
  91 err_iface:
  92         clk_disable_unprepare(qdwc->core_clk);
  93 err_core:
  94         return ret;
  95 }
  96
  97 static int dwc3_qcom_remove(struct platform_device *pdev)
  98 {
  99         struct dwc3_qcom *qdwc = platform_get_drvdata(pdev);
 100
 101         of_platform_depopulate(&pdev->dev);
 102
 103         clk_disable_unprepare(qdwc->sleep_clk);
 104         clk_disable_unprepare(qdwc->iface_clk);
 105         clk_disable_unprepare(qdwc->core_clk);
 106
 107         return 0;
 108 }
 109
 110 static const struct of_device_id of_dwc3_match[] = {
 111         { .compatible = "qcom,dwc3" },
 112         { /* Sentinel */ }
 113 };
 114 MODULE_DEVICE_TABLE(of, of_dwc3_match);
 115
 116 static struct platform_driver dwc3_qcom_driver = {
 117         .probe          = dwc3_qcom_probe,
 118         .remove         = dwc3_qcom_remove,
 119         .driver         = {
 120                 .name   = "qcom-dwc3",
 121                 .of_match_table = of_dwc3_match,
 122         },
 123 };
 124
 125 module_platform_driver(dwc3_qcom_driver);
 126
 127 MODULE_ALIAS("platform:qcom-dwc3");
 128 MODULE_LICENSE("GPL v2");
 129 MODULE_DESCRIPTION("DesignWare USB3 QCOM Glue Layer");
 130 MODULE_AUTHOR("Ivan T. Ivanov <iivanov@mm-sol.com>");