drivers/usb/host/ehci-st.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ST EHCI driver
   4  *
   5  * Copyright (C) 2014 STMicroelectronics – All Rights Reserved
   6  *
   7  * Author: Peter Griffin <[email protected]>
   8  *
   9  * Derived from ehci-platform.c
  10  */
  11
  12 #include <linux/clk.h>
  13 #include <linux/dma-mapping.h>
  14 #include <linux/err.h>
  15 #include <linux/kernel.h>
  16 #include <linux/hrtimer.h>
  17 #include <linux/io.h>
  18 #include <linux/module.h>
  19 #include <linux/of.h>
  20 #include <linux/phy/phy.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/reset.h>
  23 #include <linux/usb.h>
  24 #include <linux/usb/hcd.h>
  25 #include <linux/usb/ehci_pdriver.h>
  26
  27 #include "ehci.h"
  28
  29 #define USB_MAX_CLKS 3
  30
  31 struct st_ehci_platform_priv {
  32         struct clk *clks[USB_MAX_CLKS];
  33         struct clk *clk48;
  34         struct reset_control *rst;
  35         struct reset_control *pwr;
  36         struct phy *phy;
  37 };
  38
  39 #define DRIVER_DESC "EHCI STMicroelectronics driver"
  40
  41 #define hcd_to_ehci_priv(h) \
  42         ((struct st_ehci_platform_priv *)hcd_to_ehci(h)->priv)
  43
  44 static const char hcd_name[] = "ehci-st";
  45
  46 #define EHCI_CAPS_SIZE 0x10
  47 #define AHB2STBUS_INSREG01 (EHCI_CAPS_SIZE + 0x84)
  48
  49 static int st_ehci_platform_reset(struct usb_hcd *hcd)
  50 {
  51         struct platform_device *pdev = to_platform_device(hcd->self.controller);
  52         struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
  53         struct ehci_hcd *ehci = hcd_to_ehci(hcd);
  54         u32 threshold;
  55
  56         /* Set EHCI packet buffer IN/OUT threshold to 128 bytes */
  57         threshold = 128 | (128 << 16);
  58         writel(threshold, hcd->regs + AHB2STBUS_INSREG01);
  59
  60         ehci->caps = hcd->regs + pdata->caps_offset;
  61         return ehci_setup(hcd);
  62 }
  63
  64 static int st_ehci_platform_power_on(struct platform_device *dev)
  65 {
  66         struct usb_hcd *hcd = platform_get_drvdata(dev);
  67         struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
  68         int clk, ret;
  69
  70         ret = reset_control_deassert(priv->pwr);
  71         if (ret)
  72                 return ret;
  73
  74         ret = reset_control_deassert(priv->rst);
  75         if (ret)
  76                 goto err_assert_power;
  77
  78         /* some SoCs don't have a dedicated 48Mhz clock, but those that do
  79            need the rate to be explicitly set */
  80         if (priv->clk48) {
  81                 ret = clk_set_rate(priv->clk48, 48000000);
  82                 if (ret)
  83                         goto err_assert_reset;
  84         }
  85
  86         for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) {
  87                 ret = clk_prepare_enable(priv->clks[clk]);
  88                 if (ret)
  89                         goto err_disable_clks;
  90         }
  91
  92         ret = phy_init(priv->phy);
  93         if (ret)
  94                 goto err_disable_clks;
  95
  96         ret = phy_power_on(priv->phy);
  97         if (ret)
  98                 goto err_exit_phy;
  99
 100         return 0;
 101
 102 err_exit_phy:
 103         phy_exit(priv->phy);
 104 err_disable_clks:
 105         while (--clk >= 0)
 106                 clk_disable_unprepare(priv->clks[clk]);
 107 err_assert_reset:
 108         reset_control_assert(priv->rst);
 109 err_assert_power:
 110         reset_control_assert(priv->pwr);
 111
 112         return ret;
 113 }
 114
 115 static void st_ehci_platform_power_off(struct platform_device *dev)
 116 {
 117         struct usb_hcd *hcd = platform_get_drvdata(dev);
 118         struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
 119         int clk;
 120
 121         reset_control_assert(priv->pwr);
 122
 123         reset_control_assert(priv->rst);
 124
 125         phy_power_off(priv->phy);
 126
 127         phy_exit(priv->phy);
 128
 129         for (clk = USB_MAX_CLKS - 1; clk >= 0; clk--)
 130                 if (priv->clks[clk])
 131                         clk_disable_unprepare(priv->clks[clk]);
 132
 133 }
 134
 135 static struct hc_driver __read_mostly ehci_platform_hc_driver;
 136
 137 static const struct ehci_driver_overrides platform_overrides __initconst = {
 138         .reset =                st_ehci_platform_reset,
 139         .extra_priv_size =      sizeof(struct st_ehci_platform_priv),
 140 };
 141
 142 static struct usb_ehci_pdata ehci_platform_defaults = {
 143         .power_on =             st_ehci_platform_power_on,
 144         .power_suspend =        st_ehci_platform_power_off,
 145         .power_off =            st_ehci_platform_power_off,
 146 };
 147
 148 static int st_ehci_platform_probe(struct platform_device *dev)
 149 {
 150         struct usb_hcd *hcd;
 151         struct resource *res_mem;
 152         struct usb_ehci_pdata *pdata = &ehci_platform_defaults;
 153         struct st_ehci_platform_priv *priv;
 154         struct ehci_hcd *ehci;
 155         int err, irq, clk = 0;
 156
 157         if (usb_disabled())
 158                 return -ENODEV;
 159
 160         irq = platform_get_irq(dev, 0);
 161         if (irq < 0) {
 162                 dev_err(&dev->dev, "no irq provided");
 163                 return irq;
 164         }
 165         res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
 166         if (!res_mem) {
 167                 dev_err(&dev->dev, "no memory resource provided");
 168                 return -ENXIO;
 169         }
 170
 171         hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
 172                              dev_name(&dev->dev));
 173         if (!hcd)
 174                 return -ENOMEM;
 175
 176         platform_set_drvdata(dev, hcd);
 177         dev->dev.platform_data = pdata;
 178         priv = hcd_to_ehci_priv(hcd);
 179         ehci = hcd_to_ehci(hcd);
 180
 181         priv->phy = devm_phy_get(&dev->dev, "usb");
 182         if (IS_ERR(priv->phy)) {
 183                 err = PTR_ERR(priv->phy);
 184                 goto err_put_hcd;
 185         }
 186
 187         for (clk = 0; clk < USB_MAX_CLKS; clk++) {
 188                 priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
 189                 if (IS_ERR(priv->clks[clk])) {
 190                         err = PTR_ERR(priv->clks[clk]);
 191                         if (err == -EPROBE_DEFER)
 192                                 goto err_put_clks;
 193                         priv->clks[clk] = NULL;
 194                         break;
 195                 }
 196         }
 197
 198         /* some SoCs don't have a dedicated 48Mhz clock, but those that
 199            do need the rate to be explicitly set */
 200         priv->clk48 = devm_clk_get(&dev->dev, "clk48");
 201         if (IS_ERR(priv->clk48)) {
 202                 dev_info(&dev->dev, "48MHz clk not found\n");
 203                 priv->clk48 = NULL;
 204         }
 205
 206         priv->pwr =
 207                 devm_reset_control_get_optional_shared(&dev->dev, "power");
 208         if (IS_ERR(priv->pwr)) {
 209                 err = PTR_ERR(priv->pwr);
 210                 if (err == -EPROBE_DEFER)
 211                         goto err_put_clks;
 212                 priv->pwr = NULL;
 213         }
 214
 215         priv->rst =
 216                 devm_reset_control_get_optional_shared(&dev->dev, "softreset");
 217         if (IS_ERR(priv->rst)) {
 218                 err = PTR_ERR(priv->rst);
 219                 if (err == -EPROBE_DEFER)
 220                         goto err_put_clks;
 221                 priv->rst = NULL;
 222         }
 223
 224         if (pdata->power_on) {
 225                 err = pdata->power_on(dev);
 226                 if (err < 0)
 227                         goto err_put_clks;
 228         }
 229
 230         hcd->rsrc_start = res_mem->start;
 231         hcd->rsrc_len = resource_size(res_mem);
 232
 233         hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
 234         if (IS_ERR(hcd->regs)) {
 235                 err = PTR_ERR(hcd->regs);
 236                 goto err_put_clks;
 237         }
 238
 239         err = usb_add_hcd(hcd, irq, IRQF_SHARED);
 240         if (err)
 241                 goto err_put_clks;
 242
 243         device_wakeup_enable(hcd->self.controller);
 244         platform_set_drvdata(dev, hcd);
 245
 246         return err;
 247
 248 err_put_clks:
 249         while (--clk >= 0)
 250                 clk_put(priv->clks[clk]);
 251 err_put_hcd:
 252         if (pdata == &ehci_platform_defaults)
 253                 dev->dev.platform_data = NULL;
 254
 255         usb_put_hcd(hcd);
 256
 257         return err;
 258 }
 259
 260 static int st_ehci_platform_remove(struct platform_device *dev)
 261 {
 262         struct usb_hcd *hcd = platform_get_drvdata(dev);
 263         struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
 264         struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
 265         int clk;
 266
 267         usb_remove_hcd(hcd);
 268
 269         if (pdata->power_off)
 270                 pdata->power_off(dev);
 271
 272         for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
 273                 clk_put(priv->clks[clk]);
 274
 275         usb_put_hcd(hcd);
 276
 277         if (pdata == &ehci_platform_defaults)
 278                 dev->dev.platform_data = NULL;
 279
 280         return 0;
 281 }
 282
 283 #ifdef CONFIG_PM_SLEEP
 284
 285 static int st_ehci_suspend(struct device *dev)
 286 {
 287         struct usb_hcd *hcd = dev_get_drvdata(dev);
 288         struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
 289         struct platform_device *pdev = to_platform_device(dev);
 290         bool do_wakeup = device_may_wakeup(dev);
 291         int ret;
 292
 293         ret = ehci_suspend(hcd, do_wakeup);
 294         if (ret)
 295                 return ret;
 296
 297         if (pdata->power_suspend)
 298                 pdata->power_suspend(pdev);
 299
 300         pinctrl_pm_select_sleep_state(dev);
 301
 302         return ret;
 303 }
 304
 305 static int st_ehci_resume(struct device *dev)
 306 {
 307         struct usb_hcd *hcd = dev_get_drvdata(dev);
 308         struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
 309         struct platform_device *pdev = to_platform_device(dev);
 310         int err;
 311
 312         pinctrl_pm_select_default_state(dev);
 313
 314         if (pdata->power_on) {
 315                 err = pdata->power_on(pdev);
 316                 if (err < 0)
 317                         return err;
 318         }
 319
 320         ehci_resume(hcd, false);
 321         return 0;
 322 }
 323
 324 static SIMPLE_DEV_PM_OPS(st_ehci_pm_ops, st_ehci_suspend, st_ehci_resume);
 325
 326 #endif /* CONFIG_PM_SLEEP */
 327
 328 static const struct of_device_id st_ehci_ids[] = {
 329         { .compatible = "st,st-ehci-300x", },
 330         { /* sentinel */ }
 331 };
 332 MODULE_DEVICE_TABLE(of, st_ehci_ids);
 333
 334 static struct platform_driver ehci_platform_driver = {
 335         .probe          = st_ehci_platform_probe,
 336         .remove         = st_ehci_platform_remove,
 337         .shutdown       = usb_hcd_platform_shutdown,
 338         .driver         = {
 339                 .name   = "st-ehci",
 340 #ifdef CONFIG_PM_SLEEP
 341                 .pm     = &st_ehci_pm_ops,
 342 #endif
 343                 .of_match_table = st_ehci_ids,
 344         }
 345 };
 346
 347 static int __init ehci_platform_init(void)
 348 {
 349         if (usb_disabled())
 350                 return -ENODEV;
 351
 352         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 353
 354         ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
 355         return platform_driver_register(&ehci_platform_driver);
 356 }
 357 module_init(ehci_platform_init);
 358
 359 static void __exit ehci_platform_cleanup(void)
 360 {
 361         platform_driver_unregister(&ehci_platform_driver);
 362 }
 363 module_exit(ehci_platform_cleanup);
 364
 365 MODULE_DESCRIPTION(DRIVER_DESC);
 366 MODULE_AUTHOR("Peter Griffin <[email protected]>");
 367 MODULE_LICENSE("GPL");