drivers/usb/host/ehci-atmel.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Driver for EHCI UHP on Atmel chips
   4  *
   5  *  Copyright (C) 2009 Atmel Corporation,
   6  *                     Nicolas Ferre <nicolas.ferre@atmel.com>
   7  *
   8  *  Based on various ehci-*.c drivers
   9  */
  10
  11 #include <linux/clk.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/io.h>
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/of.h>
  17 #include <linux/of_platform.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/usb.h>
  20 #include <linux/usb/hcd.h>
  21 #include <linux/usb/phy.h>
  22 #include <linux/usb/of.h>
  23
  24 #include "ehci.h"
  25
  26 #define DRIVER_DESC "EHCI Atmel driver"
  27
  28 #define EHCI_INSNREG(index)                     ((index) * 4 + 0x90)
  29 #define EHCI_INSNREG08_HSIC_EN                  BIT(2)
  30
  31 /* interface and function clocks */
  32 #define hcd_to_atmel_ehci_priv(h) \
  33         ((struct atmel_ehci_priv *)hcd_to_ehci(h)->priv)
  34
  35 struct atmel_ehci_priv {
  36         struct clk *iclk;
  37         struct clk *uclk;
  38         bool clocked;
  39 };
  40
  41 static struct hc_driver __read_mostly ehci_atmel_hc_driver;
  42
  43 static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = {
  44         .extra_priv_size = sizeof(struct atmel_ehci_priv),
  45 };
  46
  47 /*-------------------------------------------------------------------------*/
  48
  49 static void atmel_start_clock(struct atmel_ehci_priv *atmel_ehci)
  50 {
  51         if (atmel_ehci->clocked)
  52                 return;
  53
  54         clk_prepare_enable(atmel_ehci->uclk);
  55         clk_prepare_enable(atmel_ehci->iclk);
  56         atmel_ehci->clocked = true;
  57 }
  58
  59 static void atmel_stop_clock(struct atmel_ehci_priv *atmel_ehci)
  60 {
  61         if (!atmel_ehci->clocked)
  62                 return;
  63
  64         clk_disable_unprepare(atmel_ehci->iclk);
  65         clk_disable_unprepare(atmel_ehci->uclk);
  66         atmel_ehci->clocked = false;
  67 }
  68
  69 static void atmel_start_ehci(struct platform_device *pdev)
  70 {
  71         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  72         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
  73
  74         dev_dbg(&pdev->dev, "start\n");
  75         atmel_start_clock(atmel_ehci);
  76 }
  77
  78 static void atmel_stop_ehci(struct platform_device *pdev)
  79 {
  80         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  81         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
  82
  83         dev_dbg(&pdev->dev, "stop\n");
  84         atmel_stop_clock(atmel_ehci);
  85 }
  86
  87 /*-------------------------------------------------------------------------*/
  88
  89 static int ehci_atmel_drv_probe(struct platform_device *pdev)
  90 {
  91         struct usb_hcd *hcd;
  92         const struct hc_driver *driver = &ehci_atmel_hc_driver;
  93         struct resource *res;
  94         struct ehci_hcd *ehci;
  95         struct atmel_ehci_priv *atmel_ehci;
  96         int irq;
  97         int retval;
  98
  99         if (usb_disabled())
 100                 return -ENODEV;
 101
 102         pr_debug("Initializing Atmel-SoC USB Host Controller\n");
 103
 104         irq = platform_get_irq(pdev, 0);
 105         if (irq <= 0) {
 106                 retval = -ENODEV;
 107                 goto fail_create_hcd;
 108         }
 109
 110         /* Right now device-tree probed devices don't get dma_mask set.
 111          * Since shared usb code relies on it, set it here for now.
 112          * Once we have dma capability bindings this can go away.
 113          */
 114         retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 115         if (retval)
 116                 goto fail_create_hcd;
 117
 118         hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 119         if (!hcd) {
 120                 retval = -ENOMEM;
 121                 goto fail_create_hcd;
 122         }
 123         atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
 124
 125         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 126         hcd->regs = devm_ioremap_resource(&pdev->dev, res);
 127         if (IS_ERR(hcd->regs)) {
 128                 retval = PTR_ERR(hcd->regs);
 129                 goto fail_request_resource;
 130         }
 131
 132         hcd->rsrc_start = res->start;
 133         hcd->rsrc_len = resource_size(res);
 134
 135         atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk");
 136         if (IS_ERR(atmel_ehci->iclk)) {
 137                 dev_err(&pdev->dev, "Error getting interface clock\n");
 138                 retval = -ENOENT;
 139                 goto fail_request_resource;
 140         }
 141
 142         atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk");
 143         if (IS_ERR(atmel_ehci->uclk)) {
 144                 dev_err(&pdev->dev, "failed to get uclk\n");
 145                 retval = PTR_ERR(atmel_ehci->uclk);
 146                 goto fail_request_resource;
 147         }
 148
 149         ehci = hcd_to_ehci(hcd);
 150         /* registers start at offset 0x0 */
 151         ehci->caps = hcd->regs;
 152
 153         atmel_start_ehci(pdev);
 154
 155         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 156         if (retval)
 157                 goto fail_add_hcd;
 158         device_wakeup_enable(hcd->self.controller);
 159
 160         if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_HSIC)
 161                 writel(EHCI_INSNREG08_HSIC_EN, hcd->regs + EHCI_INSNREG(8));
 162
 163         return retval;
 164
 165 fail_add_hcd:
 166         atmel_stop_ehci(pdev);
 167 fail_request_resource:
 168         usb_put_hcd(hcd);
 169 fail_create_hcd:
 170         dev_err(&pdev->dev, "init %s fail, %d\n",
 171                 dev_name(&pdev->dev), retval);
 172
 173         return retval;
 174 }
 175
 176 static void ehci_atmel_drv_remove(struct platform_device *pdev)
 177 {
 178         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 179
 180         usb_remove_hcd(hcd);
 181         usb_put_hcd(hcd);
 182
 183         atmel_stop_ehci(pdev);
 184 }
 185
 186 static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
 187 {
 188         struct usb_hcd *hcd = dev_get_drvdata(dev);
 189         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
 190         int ret;
 191
 192         ret = ehci_suspend(hcd, false);
 193         if (ret)
 194                 return ret;
 195
 196         atmel_stop_clock(atmel_ehci);
 197         return 0;
 198 }
 199
 200 static int __maybe_unused ehci_atmel_drv_resume(struct device *dev)
 201 {
 202         struct usb_hcd *hcd = dev_get_drvdata(dev);
 203         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
 204
 205         atmel_start_clock(atmel_ehci);
 206         ehci_resume(hcd, false);
 207         return 0;
 208 }
 209
 210 #ifdef CONFIG_OF
 211 static const struct of_device_id atmel_ehci_dt_ids[] = {
 212         { .compatible = "atmel,at91sam9g45-ehci" },
 213         { /* sentinel */ }
 214 };
 215
 216 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
 217 #endif
 218
 219 static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend,
 220                                         ehci_atmel_drv_resume);
 221
 222 static struct platform_driver ehci_atmel_driver = {
 223         .probe          = ehci_atmel_drv_probe,
 224         .remove_new     = ehci_atmel_drv_remove,
 225         .shutdown       = usb_hcd_platform_shutdown,
 226         .driver         = {
 227                 .name   = "atmel-ehci",
 228                 .pm     = &ehci_atmel_pm_ops,
 229                 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
 230         },
 231 };
 232
 233 static int __init ehci_atmel_init(void)
 234 {
 235         if (usb_disabled())
 236                 return -ENODEV;
 237
 238         ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides);
 239         return platform_driver_register(&ehci_atmel_driver);
 240 }
 241 module_init(ehci_atmel_init);
 242
 243 static void __exit ehci_atmel_cleanup(void)
 244 {
 245         platform_driver_unregister(&ehci_atmel_driver);
 246 }
 247 module_exit(ehci_atmel_cleanup);
 248
 249 MODULE_DESCRIPTION(DRIVER_DESC);
 250 MODULE_ALIAS("platform:atmel-ehci");
 251 MODULE_AUTHOR("Nicolas Ferre");
 252 MODULE_LICENSE("GPL");