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         unsigned int            count;
  46         int                     ret;
  47         int                     i;
  48
  49         simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
  50         if (!simple)
  51                 return -ENOMEM;
  52
  53         count = of_clk_get_parent_count(np);
  54         if (!count)
  55                 return -ENOENT;
  56
  57         simple->num_clocks = count;
  58
  59         simple->clks = devm_kcalloc(dev, simple->num_clocks,
  60                         sizeof(struct clk *), GFP_KERNEL);
  61         if (!simple->clks)
  62                 return -ENOMEM;
  63
  64         simple->dev = dev;
  65
  66         for (i = 0; i < simple->num_clocks; i++) {
  67                 struct clk      *clk;
  68
  69                 clk = of_clk_get(np, i);
  70                 if (IS_ERR(clk)) {
  71                         while (--i >= 0)
  72                                 clk_put(simple->clks[i]);
  73                         return PTR_ERR(clk);
  74                 }
  75
  76                 ret = clk_prepare_enable(clk);
  77                 if (ret < 0) {
  78                         while (--i >= 0) {
  79                                 clk_disable_unprepare(simple->clks[i]);
  80                                 clk_put(simple->clks[i]);
  81                         }
  82                         clk_put(clk);
  83
  84                         return ret;
  85                 }
  86
  87                 simple->clks[i] = clk;
  88         }
  89
  90         ret = of_platform_populate(np, NULL, NULL, dev);
  91         if (ret) {
  92                 for (i = 0; i < simple->num_clocks; i++) {
  93                         clk_disable_unprepare(simple->clks[i]);
  94                         clk_put(simple->clks[i]);
  95                 }
  96
  97                 return ret;
  98         }
  99
 100         pm_runtime_set_active(dev);
 101         pm_runtime_enable(dev);
 102         pm_runtime_get_sync(dev);
 103
 104         return 0;
 105 }
 106
 107 static int dwc3_of_simple_remove(struct platform_device *pdev)
 108 {
 109         struct dwc3_of_simple   *simple = platform_get_drvdata(pdev);
 110         struct device           *dev = &pdev->dev;
 111         int                     i;
 112
 113         for (i = 0; i < simple->num_clocks; i++) {
 114                 clk_unprepare(simple->clks[i]);
 115                 clk_put(simple->clks[i]);
 116         }
 117
 118         of_platform_depopulate(dev);
 119
 120         pm_runtime_put_sync(dev);
 121         pm_runtime_disable(dev);
 122
 123         return 0;
 124 }
 125
 126 #ifdef CONFIG_PM
 127 static int dwc3_of_simple_runtime_suspend(struct device *dev)
 128 {
 129         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 130         int                     i;
 131
 132         for (i = 0; i < simple->num_clocks; i++)
 133                 clk_disable(simple->clks[i]);
 134
 135         return 0;
 136 }
 137
 138 static int dwc3_of_simple_runtime_resume(struct device *dev)
 139 {
 140         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 141         int                     ret;
 142         int                     i;
 143
 144         for (i = 0; i < simple->num_clocks; i++) {
 145                 ret = clk_enable(simple->clks[i]);
 146                 if (ret < 0) {
 147                         while (--i >= 0)
 148                                 clk_disable(simple->clks[i]);
 149                         return ret;
 150                 }
 151         }
 152
 153         return 0;
 154 }
 155 #endif
 156
 157 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
 158         SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
 159                         dwc3_of_simple_runtime_resume, NULL)
 160 };
 161
 162 static const struct of_device_id of_dwc3_simple_match[] = {
 163         { .compatible = "qcom,dwc3" },
 164         { .compatible = "xlnx,zynqmp-dwc3" },
 165         { /* Sentinel */ }
 166 };
 167 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
 168
 169 static struct platform_driver dwc3_of_simple_driver = {
 170         .probe          = dwc3_of_simple_probe,
 171         .remove         = dwc3_of_simple_remove,
 172         .driver         = {
 173                 .name   = "dwc3-of-simple",
 174                 .of_match_table = of_dwc3_simple_match,
 175         },
 176 };
 177
 178 module_platform_driver(dwc3_of_simple_driver);
 179 MODULE_LICENSE("GPL v2");
 180 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
 181 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");