drivers/usb/dwc3/dwc3-of-simple.c

   1 /**
   2  * dwc3-of-simple.c - OF glue layer for simple integrations
   3  *
   4  * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com
   5  *
   6  * Author: Felipe Balbi <balbi@ti.com>
   7  *
   8  * This program is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2  of
  10  * the License as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * This is a combination of the old dwc3-qcom.c by Ivan T. Ivanov
  18  * <iivanov@mm-sol.com> and the original patch adding support for Xilinx' SoC
  19  * by Subbaraya Sundeep Bhatta <subbaraya.sundeep.bhatta@xilinx.com>
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/slab.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/dma-mapping.h>
  27 #include <linux/clk.h>
  28 #include <linux/clk-provider.h>
  29 #include <linux/of.h>
  30 #include <linux/of_platform.h>
  31 #include <linux/pm_runtime.h>
  32
  33 struct dwc3_of_simple {
  34         struct device           *dev;
  35         struct clk              **clks;
  36         int                     num_clocks;
  37 };
  38
  39 static int dwc3_of_simple_probe(struct platform_device *pdev)
  40 {
  41         struct dwc3_of_simple   *simple;
  42         struct device           *dev = &pdev->dev;
  43         struct device_node      *np = dev->of_node;
  44
  45         int                     ret;
  46         int                     i;
  47
  48         simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
  49         if (!simple)
  50                 return -ENOMEM;
  51
  52         ret = of_clk_get_parent_count(np);
  53         if (ret < 0)
  54                 return ret;
  55
  56         simple->num_clocks = ret;
  57
  58         simple->clks = devm_kcalloc(dev, simple->num_clocks,
  59                         sizeof(struct clk *), GFP_KERNEL);
  60         if (!simple->clks)
  61                 return -ENOMEM;
  62
  63         simple->dev = dev;
  64
  65         for (i = 0; i < simple->num_clocks; i++) {
  66                 struct clk      *clk;
  67
  68                 clk = of_clk_get(np, i);
  69                 if (IS_ERR(clk)) {
  70                         while (--i >= 0)
  71                                 clk_put(simple->clks[i]);
  72                         return PTR_ERR(clk);
  73                 }
  74
  75                 ret = clk_prepare_enable(clk);
  76                 if (ret < 0) {
  77                         while (--i >= 0) {
  78                                 clk_disable_unprepare(simple->clks[i]);
  79                                 clk_put(simple->clks[i]);
  80                         }
  81                         clk_put(clk);
  82
  83                         return ret;
  84                 }
  85
  86                 simple->clks[i] = clk;
  87         }
  88
  89         ret = of_platform_populate(np, NULL, NULL, dev);
  90         if (ret) {
  91                 for (i = 0; i < simple->num_clocks; i++) {
  92                         clk_disable_unprepare(simple->clks[i]);
  93                         clk_put(simple->clks[i]);
  94                 }
  95
  96                 return ret;
  97         }
  98
  99         pm_runtime_set_active(dev);
 100         pm_runtime_enable(dev);
 101         pm_runtime_get_sync(dev);
 102
 103         return 0;
 104 }
 105
 106 static int dwc3_of_simple_remove(struct platform_device *pdev)
 107 {
 108         struct dwc3_of_simple   *simple = platform_get_drvdata(pdev);
 109         struct device           *dev = &pdev->dev;
 110         int                     i;
 111
 112         for (i = 0; i < simple->num_clocks; i++) {
 113                 clk_unprepare(simple->clks[i]);
 114                 clk_put(simple->clks[i]);
 115         }
 116
 117         of_platform_depopulate(dev);
 118
 119         pm_runtime_put_sync(dev);
 120         pm_runtime_disable(dev);
 121
 122         return 0;
 123 }
 124
 125 #ifdef CONFIG_PM
 126 static int dwc3_of_simple_runtime_suspend(struct device *dev)
 127 {
 128         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 129         int                     i;
 130
 131         for (i = 0; i < simple->num_clocks; i++)
 132                 clk_disable(simple->clks[i]);
 133
 134         return 0;
 135 }
 136
 137 static int dwc3_of_simple_runtime_resume(struct device *dev)
 138 {
 139         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 140         int                     ret;
 141         int                     i;
 142
 143         for (i = 0; i < simple->num_clocks; i++) {
 144                 ret = clk_enable(simple->clks[i]);
 145                 if (ret < 0) {
 146                         while (--i >= 0)
 147                                 clk_disable(simple->clks[i]);
 148                         return ret;
 149                 }
 150         }
 151
 152         return 0;
 153 }
 154 #endif
 155
 156 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
 157         SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
 158                         dwc3_of_simple_runtime_resume, NULL)
 159 };
 160
 161 static const struct of_device_id of_dwc3_simple_match[] = {
 162         { .compatible = "qcom,dwc3" },
 163         { .compatible = "xlnx,zynqmp-dwc3" },
 164         { /* Sentinel */ }
 165 };
 166 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
 167
 168 static struct platform_driver dwc3_of_simple_driver = {
 169         .probe          = dwc3_of_simple_probe,
 170         .remove         = dwc3_of_simple_remove,
 171         .driver         = {
 172                 .name   = "dwc3-of-simple",
 173                 .of_match_table = of_dwc3_simple_match,
 174         },
 175 };
 176
 177 module_platform_driver(dwc3_of_simple_driver);
 178 MODULE_LICENSE("GPL v2");
 179 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
 180 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");