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 static const char hcd_name[] = "ehci-atmel";
  29
  30 #define EHCI_INSNREG(index)                     ((index) * 4 + 0x90)
  31 #define EHCI_INSNREG08_HSIC_EN                  BIT(2)
  32
  33 /* interface and function clocks */
  34 #define hcd_to_atmel_ehci_priv(h) \
  35         ((struct atmel_ehci_priv *)hcd_to_ehci(h)->priv)
  36
  37 struct atmel_ehci_priv {
  38         struct clk *iclk;
  39         struct clk *uclk;
  40         bool clocked;
  41 };
  42
  43 static struct hc_driver __read_mostly ehci_atmel_hc_driver;
  44
  45 static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = {
  46         .extra_priv_size = sizeof(struct atmel_ehci_priv),
  47 };
  48
  49 /*-------------------------------------------------------------------------*/
  50
  51 static void atmel_start_clock(struct atmel_ehci_priv *atmel_ehci)
  52 {
  53         if (atmel_ehci->clocked)
  54                 return;
  55
  56         clk_prepare_enable(atmel_ehci->uclk);
  57         clk_prepare_enable(atmel_ehci->iclk);
  58         atmel_ehci->clocked = true;
  59 }
  60
  61 static void atmel_stop_clock(struct atmel_ehci_priv *atmel_ehci)
  62 {
  63         if (!atmel_ehci->clocked)
  64                 return;
  65
  66         clk_disable_unprepare(atmel_ehci->iclk);
  67         clk_disable_unprepare(atmel_ehci->uclk);
  68         atmel_ehci->clocked = false;
  69 }
  70
  71 static void atmel_start_ehci(struct platform_device *pdev)
  72 {
  73         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  74         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
  75
  76         dev_dbg(&pdev->dev, "start\n");
  77         atmel_start_clock(atmel_ehci);
  78 }
  79
  80 static void atmel_stop_ehci(struct platform_device *pdev)
  81 {
  82         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  83         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
  84
  85         dev_dbg(&pdev->dev, "stop\n");
  86         atmel_stop_clock(atmel_ehci);
  87 }
  88
  89 /*-------------------------------------------------------------------------*/
  90
  91 static int ehci_atmel_drv_probe(struct platform_device *pdev)
  92 {
  93         struct usb_hcd *hcd;
  94         const struct hc_driver *driver = &ehci_atmel_hc_driver;
  95         struct resource *res;
  96         struct ehci_hcd *ehci;
  97         struct atmel_ehci_priv *atmel_ehci;
  98         int irq;
  99         int retval;
 100
 101         if (usb_disabled())
 102                 return -ENODEV;
 103
 104         pr_debug("Initializing Atmel-SoC USB Host Controller\n");
 105
 106         irq = platform_get_irq(pdev, 0);
 107         if (irq <= 0) {
 108                 retval = -ENODEV;
 109                 goto fail_create_hcd;
 110         }
 111
 112         /* Right now device-tree probed devices don't get dma_mask set.
 113          * Since shared usb code relies on it, set it here for now.
 114          * Once we have dma capability bindings this can go away.
 115          */
 116         retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 117         if (retval)
 118                 goto fail_create_hcd;
 119
 120         hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 121         if (!hcd) {
 122                 retval = -ENOMEM;
 123                 goto fail_create_hcd;
 124         }
 125         atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
 126
 127         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 128         hcd->regs = devm_ioremap_resource(&pdev->dev, res);
 129         if (IS_ERR(hcd->regs)) {
 130                 retval = PTR_ERR(hcd->regs);
 131                 goto fail_request_resource;
 132         }
 133
 134         hcd->rsrc_start = res->start;
 135         hcd->rsrc_len = resource_size(res);
 136
 137         atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk");
 138         if (IS_ERR(atmel_ehci->iclk)) {
 139                 dev_err(&pdev->dev, "Error getting interface clock\n");
 140                 retval = -ENOENT;
 141                 goto fail_request_resource;
 142         }
 143
 144         atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk");
 145         if (IS_ERR(atmel_ehci->uclk)) {
 146                 dev_err(&pdev->dev, "failed to get uclk\n");
 147                 retval = PTR_ERR(atmel_ehci->uclk);
 148                 goto fail_request_resource;
 149         }
 150
 151         ehci = hcd_to_ehci(hcd);
 152         /* registers start at offset 0x0 */
 153         ehci->caps = hcd->regs;
 154
 155         atmel_start_ehci(pdev);
 156
 157         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 158         if (retval)
 159                 goto fail_add_hcd;
 160         device_wakeup_enable(hcd->self.controller);
 161
 162         if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_HSIC)
 163                 writel(EHCI_INSNREG08_HSIC_EN, hcd->regs + EHCI_INSNREG(8));
 164
 165         return retval;
 166
 167 fail_add_hcd:
 168         atmel_stop_ehci(pdev);
 169 fail_request_resource:
 170         usb_put_hcd(hcd);
 171 fail_create_hcd:
 172         dev_err(&pdev->dev, "init %s fail, %d\n",
 173                 dev_name(&pdev->dev), retval);
 174
 175         return retval;
 176 }
 177
 178 static int ehci_atmel_drv_remove(struct platform_device *pdev)
 179 {
 180         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 181
 182         usb_remove_hcd(hcd);
 183         usb_put_hcd(hcd);
 184
 185         atmel_stop_ehci(pdev);
 186
 187         return 0;
 188 }
 189
 190 static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
 191 {
 192         struct usb_hcd *hcd = dev_get_drvdata(dev);
 193         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
 194         int ret;
 195
 196         ret = ehci_suspend(hcd, false);
 197         if (ret)
 198                 return ret;
 199
 200         atmel_stop_clock(atmel_ehci);
 201         return 0;
 202 }
 203
 204 static int __maybe_unused ehci_atmel_drv_resume(struct device *dev)
 205 {
 206         struct usb_hcd *hcd = dev_get_drvdata(dev);
 207         struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
 208
 209         atmel_start_clock(atmel_ehci);
 210         ehci_resume(hcd, false);
 211         return 0;
 212 }
 213
 214 #ifdef CONFIG_OF
 215 static const struct of_device_id atmel_ehci_dt_ids[] = {
 216         { .compatible = "atmel,at91sam9g45-ehci" },
 217         { /* sentinel */ }
 218 };
 219
 220 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
 221 #endif
 222
 223 static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend,
 224                                         ehci_atmel_drv_resume);
 225
 226 static struct platform_driver ehci_atmel_driver = {
 227         .probe          = ehci_atmel_drv_probe,
 228         .remove         = ehci_atmel_drv_remove,
 229         .shutdown       = usb_hcd_platform_shutdown,
 230         .driver         = {
 231                 .name   = "atmel-ehci",
 232                 .pm     = &ehci_atmel_pm_ops,
 233                 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
 234         },
 235 };
 236
 237 static int __init ehci_atmel_init(void)
 238 {
 239         if (usb_disabled())
 240                 return -ENODEV;
 241
 242         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 243         ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides);
 244         return platform_driver_register(&ehci_atmel_driver);
 245 }
 246 module_init(ehci_atmel_init);
 247
 248 static void __exit ehci_atmel_cleanup(void)
 249 {
 250         platform_driver_unregister(&ehci_atmel_driver);
 251 }
 252 module_exit(ehci_atmel_cleanup);
 253
 254 MODULE_DESCRIPTION(DRIVER_DESC);
 255 MODULE_ALIAS("platform:atmel-ehci");
 256 MODULE_AUTHOR("Nicolas Ferre");
 257 MODULE_LICENSE("GPL");