drivers/usb/host/ohci-st.c

   1 /*
   2  * ST OHCI driver
   3  *
   4  * Copyright (C) 2014 STMicroelectronics – All Rights Reserved
   5  *
   6  * Author: Peter Griffin <peter.griffin@linaro.org>
   7  *
   8  * Derived from ohci-platform.c
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/clk.h>
  16 #include <linux/dma-mapping.h>
  17 #include <linux/hrtimer.h>
  18 #include <linux/io.h>
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/err.h>
  22 #include <linux/phy/phy.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/reset.h>
  25 #include <linux/usb/ohci_pdriver.h>
  26 #include <linux/usb.h>
  27 #include <linux/usb/hcd.h>
  28
  29 #include "ohci.h"
  30
  31 #define USB_MAX_CLKS 3
  32
  33 struct st_ohci_platform_priv {
  34         struct clk *clks[USB_MAX_CLKS];
  35         struct clk *clk48;
  36         struct reset_control *rst;
  37         struct reset_control *pwr;
  38         struct phy *phy;
  39 };
  40
  41 #define DRIVER_DESC "OHCI STMicroelectronics driver"
  42
  43 #define hcd_to_ohci_priv(h) \
  44         ((struct st_ohci_platform_priv *)hcd_to_ohci(h)->priv)
  45
  46 static const char hcd_name[] = "ohci-st";
  47
  48 static int st_ohci_platform_power_on(struct platform_device *dev)
  49 {
  50         struct usb_hcd *hcd = platform_get_drvdata(dev);
  51         struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
  52         int clk, ret;
  53
  54         ret = reset_control_deassert(priv->pwr);
  55         if (ret)
  56                 return ret;
  57
  58         ret = reset_control_deassert(priv->rst);
  59         if (ret)
  60                 goto err_assert_power;
  61
  62         /* some SoCs don't have a dedicated 48Mhz clock, but those that do
  63            need the rate to be explicitly set */
  64         if (priv->clk48) {
  65                 ret = clk_set_rate(priv->clk48, 48000000);
  66                 if (ret)
  67                         goto err_assert_reset;
  68         }
  69
  70         for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) {
  71                 ret = clk_prepare_enable(priv->clks[clk]);
  72                 if (ret)
  73                         goto err_disable_clks;
  74         }
  75
  76         ret = phy_init(priv->phy);
  77         if (ret)
  78                 goto err_disable_clks;
  79
  80         ret = phy_power_on(priv->phy);
  81         if (ret)
  82                 goto err_exit_phy;
  83
  84         return 0;
  85
  86 err_exit_phy:
  87         phy_exit(priv->phy);
  88 err_disable_clks:
  89         while (--clk >= 0)
  90                 clk_disable_unprepare(priv->clks[clk]);
  91 err_assert_reset:
  92         reset_control_assert(priv->rst);
  93 err_assert_power:
  94         reset_control_assert(priv->pwr);
  95
  96         return ret;
  97 }
  98
  99 static void st_ohci_platform_power_off(struct platform_device *dev)
 100 {
 101         struct usb_hcd *hcd = platform_get_drvdata(dev);
 102         struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
 103
 104         int clk;
 105
 106         reset_control_assert(priv->pwr);
 107
 108         reset_control_assert(priv->rst);
 109
 110         phy_power_off(priv->phy);
 111
 112         phy_exit(priv->phy);
 113
 114         for (clk = USB_MAX_CLKS - 1; clk >= 0; clk--)
 115                 if (priv->clks[clk])
 116                         clk_disable_unprepare(priv->clks[clk]);
 117 }
 118
 119 static struct hc_driver __read_mostly ohci_platform_hc_driver;
 120
 121 static const struct ohci_driver_overrides platform_overrides __initconst = {
 122         .product_desc =         "ST OHCI controller",
 123         .extra_priv_size =      sizeof(struct st_ohci_platform_priv),
 124 };
 125
 126 static struct usb_ohci_pdata ohci_platform_defaults = {
 127         .power_on =             st_ohci_platform_power_on,
 128         .power_suspend =        st_ohci_platform_power_off,
 129         .power_off =            st_ohci_platform_power_off,
 130 };
 131
 132 static int st_ohci_platform_probe(struct platform_device *dev)
 133 {
 134         struct usb_hcd *hcd;
 135         struct resource *res_mem;
 136         struct usb_ohci_pdata *pdata = &ohci_platform_defaults;
 137         struct st_ohci_platform_priv *priv;
 138         struct ohci_hcd *ohci;
 139         int err, irq, clk = 0;
 140
 141         if (usb_disabled())
 142                 return -ENODEV;
 143
 144         irq = platform_get_irq(dev, 0);
 145         if (irq < 0) {
 146                 dev_err(&dev->dev, "no irq provided");
 147                 return irq;
 148         }
 149
 150         res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
 151         if (!res_mem) {
 152                 dev_err(&dev->dev, "no memory resource provided");
 153                 return -ENXIO;
 154         }
 155
 156         hcd = usb_create_hcd(&ohci_platform_hc_driver, &dev->dev,
 157                         dev_name(&dev->dev));
 158         if (!hcd)
 159                 return -ENOMEM;
 160
 161         platform_set_drvdata(dev, hcd);
 162         dev->dev.platform_data = pdata;
 163         priv = hcd_to_ohci_priv(hcd);
 164         ohci = hcd_to_ohci(hcd);
 165
 166         priv->phy = devm_phy_get(&dev->dev, "usb");
 167         if (IS_ERR(priv->phy)) {
 168                 err = PTR_ERR(priv->phy);
 169                 goto err_put_hcd;
 170         }
 171
 172         for (clk = 0; clk < USB_MAX_CLKS; clk++) {
 173                 priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
 174                 if (IS_ERR(priv->clks[clk])) {
 175                         err = PTR_ERR(priv->clks[clk]);
 176                         if (err == -EPROBE_DEFER)
 177                                 goto err_put_clks;
 178                         priv->clks[clk] = NULL;
 179                         break;
 180                 }
 181         }
 182
 183         /* some SoCs don't have a dedicated 48Mhz clock, but those that
 184            do need the rate to be explicitly set */
 185         priv->clk48 = devm_clk_get(&dev->dev, "clk48");
 186         if (IS_ERR(priv->clk48)) {
 187                 dev_info(&dev->dev, "48MHz clk not found\n");
 188                 priv->clk48 = NULL;
 189         }
 190
 191         priv->pwr =
 192                 devm_reset_control_get_optional_shared(&dev->dev, "power");
 193         if (IS_ERR(priv->pwr)) {
 194                 err = PTR_ERR(priv->pwr);
 195                 goto err_put_clks;
 196         }
 197
 198         priv->rst =
 199                 devm_reset_control_get_optional_shared(&dev->dev, "softreset");
 200         if (IS_ERR(priv->rst)) {
 201                 err = PTR_ERR(priv->rst);
 202                 goto err_put_clks;
 203         }
 204
 205         if (pdata->power_on) {
 206                 err = pdata->power_on(dev);
 207                 if (err < 0)
 208                         goto err_power;
 209         }
 210
 211         hcd->rsrc_start = res_mem->start;
 212         hcd->rsrc_len = resource_size(res_mem);
 213
 214         hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
 215         if (IS_ERR(hcd->regs)) {
 216                 err = PTR_ERR(hcd->regs);
 217                 goto err_power;
 218         }
 219         err = usb_add_hcd(hcd, irq, IRQF_SHARED);
 220         if (err)
 221                 goto err_power;
 222
 223         device_wakeup_enable(hcd->self.controller);
 224
 225         platform_set_drvdata(dev, hcd);
 226
 227         return err;
 228
 229 err_power:
 230         if (pdata->power_off)
 231                 pdata->power_off(dev);
 232
 233 err_put_clks:
 234         while (--clk >= 0)
 235                 clk_put(priv->clks[clk]);
 236 err_put_hcd:
 237         if (pdata == &ohci_platform_defaults)
 238                 dev->dev.platform_data = NULL;
 239
 240         usb_put_hcd(hcd);
 241
 242         return err;
 243 }
 244
 245 static int st_ohci_platform_remove(struct platform_device *dev)
 246 {
 247         struct usb_hcd *hcd = platform_get_drvdata(dev);
 248         struct usb_ohci_pdata *pdata = dev_get_platdata(&dev->dev);
 249         struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
 250         int clk;
 251
 252         usb_remove_hcd(hcd);
 253
 254         if (pdata->power_off)
 255                 pdata->power_off(dev);
 256
 257
 258         for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
 259                 clk_put(priv->clks[clk]);
 260
 261         usb_put_hcd(hcd);
 262
 263         if (pdata == &ohci_platform_defaults)
 264                 dev->dev.platform_data = NULL;
 265
 266         return 0;
 267 }
 268
 269 #ifdef CONFIG_PM_SLEEP
 270
 271 static int st_ohci_suspend(struct device *dev)
 272 {
 273         struct usb_hcd *hcd = dev_get_drvdata(dev);
 274         struct usb_ohci_pdata *pdata = dev->platform_data;
 275         struct platform_device *pdev = to_platform_device(dev);
 276         bool do_wakeup = device_may_wakeup(dev);
 277         int ret;
 278
 279         ret = ohci_suspend(hcd, do_wakeup);
 280         if (ret)
 281                 return ret;
 282
 283         if (pdata->power_suspend)
 284                 pdata->power_suspend(pdev);
 285
 286         return ret;
 287 }
 288
 289 static int st_ohci_resume(struct device *dev)
 290 {
 291         struct usb_hcd *hcd = dev_get_drvdata(dev);
 292         struct usb_ohci_pdata *pdata = dev_get_platdata(dev);
 293         struct platform_device *pdev = to_platform_device(dev);
 294         int err;
 295
 296         if (pdata->power_on) {
 297                 err = pdata->power_on(pdev);
 298                 if (err < 0)
 299                         return err;
 300         }
 301
 302         ohci_resume(hcd, false);
 303         return 0;
 304 }
 305
 306 static SIMPLE_DEV_PM_OPS(st_ohci_pm_ops, st_ohci_suspend, st_ohci_resume);
 307
 308 #endif /* CONFIG_PM_SLEEP */
 309
 310 static const struct of_device_id st_ohci_platform_ids[] = {
 311         { .compatible = "st,st-ohci-300x", },
 312         { /* sentinel */ }
 313 };
 314 MODULE_DEVICE_TABLE(of, st_ohci_platform_ids);
 315
 316 static struct platform_driver ohci_platform_driver = {
 317         .probe          = st_ohci_platform_probe,
 318         .remove         = st_ohci_platform_remove,
 319         .shutdown       = usb_hcd_platform_shutdown,
 320         .driver         = {
 321                 .name   = "st-ohci",
 322 #ifdef CONFIG_PM_SLEEP
 323                 .pm     = &st_ohci_pm_ops,
 324 #endif
 325                 .of_match_table = st_ohci_platform_ids,
 326         }
 327 };
 328
 329 static int __init ohci_platform_init(void)
 330 {
 331         if (usb_disabled())
 332                 return -ENODEV;
 333
 334         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 335
 336         ohci_init_driver(&ohci_platform_hc_driver, &platform_overrides);
 337         return platform_driver_register(&ohci_platform_driver);
 338 }
 339 module_init(ohci_platform_init);
 340
 341 static void __exit ohci_platform_cleanup(void)
 342 {
 343         platform_driver_unregister(&ohci_platform_driver);
 344 }
 345 module_exit(ohci_platform_cleanup);
 346
 347 MODULE_DESCRIPTION(DRIVER_DESC);
 348 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
 349 MODULE_LICENSE("GPL");