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

   1 // SPDX-License-Identifier: GPL-2.0
   2 /**
   3  * dwc3-of-simple.c - OF glue layer for simple integrations
   4  *
   5  * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com
   6  *
   7  * Author: Felipe Balbi <balbi@ti.com>
   8  *
   9  * This program is free software: you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2  of
  11  * the License as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * This is a combination of the old dwc3-qcom.c by Ivan T. Ivanov
  19  * <iivanov@mm-sol.com> and the original patch adding support for Xilinx' SoC
  20  * by Subbaraya Sundeep Bhatta <subbaraya.sundeep.bhatta@xilinx.com>
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/kernel.h>
  25 #include <linux/slab.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/dma-mapping.h>
  28 #include <linux/clk.h>
  29 #include <linux/of.h>
  30 #include <linux/of_platform.h>
  31 #include <linux/pm_runtime.h>
  32 #include <linux/reset.h>
  33
  34 struct dwc3_of_simple {
  35         struct device           *dev;
  36         struct clk              **clks;
  37         int                     num_clocks;
  38         struct reset_control    *resets;
  39 };
  40
  41 static int dwc3_of_simple_clk_init(struct dwc3_of_simple *simple, int count)
  42 {
  43         struct device           *dev = simple->dev;
  44         struct device_node      *np = dev->of_node;
  45         int                     i;
  46
  47         simple->num_clocks = count;
  48
  49         if (!count)
  50                 return 0;
  51
  52         simple->clks = devm_kcalloc(dev, simple->num_clocks,
  53                         sizeof(struct clk *), GFP_KERNEL);
  54         if (!simple->clks)
  55                 return -ENOMEM;
  56
  57         for (i = 0; i < simple->num_clocks; i++) {
  58                 struct clk      *clk;
  59                 int             ret;
  60
  61                 clk = of_clk_get(np, i);
  62                 if (IS_ERR(clk)) {
  63                         while (--i >= 0)
  64                                 clk_put(simple->clks[i]);
  65                         return PTR_ERR(clk);
  66                 }
  67
  68                 ret = clk_prepare_enable(clk);
  69                 if (ret < 0) {
  70                         while (--i >= 0) {
  71                                 clk_disable_unprepare(simple->clks[i]);
  72                                 clk_put(simple->clks[i]);
  73                         }
  74                         clk_put(clk);
  75
  76                         return ret;
  77                 }
  78
  79                 simple->clks[i] = clk;
  80         }
  81
  82         return 0;
  83 }
  84
  85 static int dwc3_of_simple_probe(struct platform_device *pdev)
  86 {
  87         struct dwc3_of_simple   *simple;
  88         struct device           *dev = &pdev->dev;
  89         struct device_node      *np = dev->of_node;
  90
  91         int                     ret;
  92         int                     i;
  93
  94         simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
  95         if (!simple)
  96                 return -ENOMEM;
  97
  98         platform_set_drvdata(pdev, simple);
  99         simple->dev = dev;
 100
 101         simple->resets = of_reset_control_array_get_optional_exclusive(np);
 102         if (IS_ERR(simple->resets)) {
 103                 ret = PTR_ERR(simple->resets);
 104                 dev_err(dev, "failed to get device resets, err=%d\n", ret);
 105                 return ret;
 106         }
 107
 108         ret = reset_control_deassert(simple->resets);
 109         if (ret)
 110                 goto err_resetc_put;
 111
 112         ret = dwc3_of_simple_clk_init(simple, of_count_phandle_with_args(np,
 113                                                 "clocks", "#clock-cells"));
 114         if (ret)
 115                 goto err_resetc_assert;
 116
 117         ret = of_platform_populate(np, NULL, NULL, dev);
 118         if (ret) {
 119                 for (i = 0; i < simple->num_clocks; i++) {
 120                         clk_disable_unprepare(simple->clks[i]);
 121                         clk_put(simple->clks[i]);
 122                 }
 123
 124                 goto err_resetc_assert;
 125         }
 126
 127         pm_runtime_set_active(dev);
 128         pm_runtime_enable(dev);
 129         pm_runtime_get_sync(dev);
 130
 131         return 0;
 132
 133 err_resetc_assert:
 134         reset_control_assert(simple->resets);
 135
 136 err_resetc_put:
 137         reset_control_put(simple->resets);
 138         return ret;
 139 }
 140
 141 static int dwc3_of_simple_remove(struct platform_device *pdev)
 142 {
 143         struct dwc3_of_simple   *simple = platform_get_drvdata(pdev);
 144         struct device           *dev = &pdev->dev;
 145         int                     i;
 146
 147         of_platform_depopulate(dev);
 148
 149         for (i = 0; i < simple->num_clocks; i++) {
 150                 clk_disable_unprepare(simple->clks[i]);
 151                 clk_put(simple->clks[i]);
 152         }
 153
 154         reset_control_assert(simple->resets);
 155         reset_control_put(simple->resets);
 156
 157         pm_runtime_put_sync(dev);
 158         pm_runtime_disable(dev);
 159
 160         return 0;
 161 }
 162
 163 #ifdef CONFIG_PM
 164 static int dwc3_of_simple_runtime_suspend(struct device *dev)
 165 {
 166         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 167         int                     i;
 168
 169         for (i = 0; i < simple->num_clocks; i++)
 170                 clk_disable(simple->clks[i]);
 171
 172         return 0;
 173 }
 174
 175 static int dwc3_of_simple_runtime_resume(struct device *dev)
 176 {
 177         struct dwc3_of_simple   *simple = dev_get_drvdata(dev);
 178         int                     ret;
 179         int                     i;
 180
 181         for (i = 0; i < simple->num_clocks; i++) {
 182                 ret = clk_enable(simple->clks[i]);
 183                 if (ret < 0) {
 184                         while (--i >= 0)
 185                                 clk_disable(simple->clks[i]);
 186                         return ret;
 187                 }
 188         }
 189
 190         return 0;
 191 }
 192 #endif
 193
 194 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
 195         SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
 196                         dwc3_of_simple_runtime_resume, NULL)
 197 };
 198
 199 static const struct of_device_id of_dwc3_simple_match[] = {
 200         { .compatible = "qcom,dwc3" },
 201         { .compatible = "rockchip,rk3399-dwc3" },
 202         { .compatible = "xlnx,zynqmp-dwc3" },
 203         { .compatible = "cavium,octeon-7130-usb-uctl" },
 204         { .compatible = "sprd,sc9860-dwc3" },
 205         { /* Sentinel */ }
 206 };
 207 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
 208
 209 static struct platform_driver dwc3_of_simple_driver = {
 210         .probe          = dwc3_of_simple_probe,
 211         .remove         = dwc3_of_simple_remove,
 212         .driver         = {
 213                 .name   = "dwc3-of-simple",
 214                 .of_match_table = of_dwc3_simple_match,
 215         },
 216 };
 217
 218 module_platform_driver(dwc3_of_simple_driver);
 219 MODULE_LICENSE("GPL v2");
 220 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
 221 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");