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