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_clk_init(struct dwc3_of_simple *simple, int count)
  40 {
  41         struct device           *dev = simple->dev;
  42         struct device_node      *np = dev->of_node;
  43         int                     i;
  44
  45         simple->num_clocks = count;
  46
  47         if (!count)
  48                 return 0;
  49
  50         simple->clks = devm_kcalloc(dev, simple->num_clocks,
  51                         sizeof(struct clk *), GFP_KERNEL);
  52         if (!simple->clks)
  53                 return -ENOMEM;
  54
  55         for (i = 0; i < simple->num_clocks; i++) {
  56                 struct clk      *clk;
  57                 int             ret;
  58
  59                 clk = of_clk_get(np, i);
  60                 if (IS_ERR(clk)) {
  61                         while (--i >= 0)
  62                                 clk_put(simple->clks[i]);
  63                         return PTR_ERR(clk);
  64                 }
  65
  66                 ret = clk_prepare_enable(clk);
  67                 if (ret < 0) {
  68                         while (--i >= 0) {
  69                                 clk_disable_unprepare(simple->clks[i]);
  70                                 clk_put(simple->clks[i]);
  71                         }
  72                         clk_put(clk);
  73
  74                         return ret;
  75                 }
  76
  77                 simple->clks[i] = clk;
  78         }
  79
  80         return 0;
  81 }
  82
  83 static int dwc3_of_simple_probe(struct platform_device *pdev)
  84 {
  85         struct dwc3_of_simple   *simple;
  86         struct device           *dev = &pdev->dev;
  87         struct device_node      *np = dev->of_node;
  88
  89         int                     ret;
  90         int                     i;
  91
  92         simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
  93         if (!simple)
  94                 return -ENOMEM;
  95
  96         platform_set_drvdata(pdev, simple);
  97         simple->dev = dev;
  98
  99         ret = dwc3_of_simple_clk_init(simple, of_clk_get_parent_count(np));
 100         if (ret)
 101                 return ret;
 102
 103         ret = of_platform_populate(np, NULL, NULL, dev);
 104         if (ret) {
 105                 for (i = 0; i < simple->num_clocks; i++) {
 106                         clk_disable_unprepare(simple->clks[i]);
 107                         clk_put(simple->clks[i]);
 108                 }
 109
 110                 return ret;
 111         }
 112
 113         pm_runtime_set_active(dev);
 114         pm_runtime_enable(dev);
 115         pm_runtime_get_sync(dev);
 116
 117         return 0;
 118 }
 119
 120 static int dwc3_of_simple_remove(struct platform_device *pdev)
 121 {
 122         struct dwc3_of_simple   *simple = platform_get_drvdata(pdev);
 123         struct device           *dev = &pdev->dev;
 124         int                     i;
 125
 126         for (i = 0; i < simple->num_clocks; i++) {
 127                 clk_disable_unprepare(simple->clks[i]);
 128                 clk_put(simple->clks[i]);
 129         }
 130
 131         of_platform_depopulate(dev);
 132
 133         pm_runtime_put_sync(dev);
 134         pm_runtime_disable(dev);
 135
 136         return 0;
 137 }
 138
 139 #ifdef CONFIG_PM
 140 static int dwc3_of_simple_runtime_suspend(struct device *dev)
 141 {
 142         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 143         int                     i;
 144
 145         for (i = 0; i < simple->num_clocks; i++)
 146                 clk_disable(simple->clks[i]);
 147
 148         return 0;
 149 }
 150
 151 static int dwc3_of_simple_runtime_resume(struct device *dev)
 152 {
 153         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 154         int                     ret;
 155         int                     i;
 156
 157         for (i = 0; i < simple->num_clocks; i++) {
 158                 ret = clk_enable(simple->clks[i]);
 159                 if (ret < 0) {
 160                         while (--i >= 0)
 161                                 clk_disable(simple->clks[i]);
 162                         return ret;
 163                 }
 164         }
 165
 166         return 0;
 167 }
 168 #endif
 169
 170 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
 171         SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
 172                         dwc3_of_simple_runtime_resume, NULL)
 173 };
 174
 175 static const struct of_device_id of_dwc3_simple_match[] = {
 176         { .compatible = "qcom,dwc3" },
 177         { .compatible = "rockchip,rk3399-dwc3" },
 178         { .compatible = "xlnx,zynqmp-dwc3" },
 179         { .compatible = "cavium,octeon-7130-usb-uctl" },
 180         { /* Sentinel */ }
 181 };
 182 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
 183
 184 static struct platform_driver dwc3_of_simple_driver = {
 185         .probe          = dwc3_of_simple_probe,
 186         .remove         = dwc3_of_simple_remove,
 187         .driver         = {
 188                 .name   = "dwc3-of-simple",
 189                 .of_match_table = of_dwc3_simple_match,
 190         },
 191 };
 192
 193 module_platform_driver(dwc3_of_simple_driver);
 194 MODULE_LICENSE("GPL v2");
 195 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
 196 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");