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