Quelle  uhci-platform.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/*
 * Generic UHCI HCD (Host Controller Driver) for Platform Devices
 *
 * Copyright (c) 2011 Tony Prisk <linux@prisktech.co.nz>
 *
 * This file is based on uhci-grlib.c
 * (C) Copyright 2004-2007 Alan Stern, stern@rowland.harvard.edu
 */

#include <linux/of.h>
#include <linux/device.h>
#include <linux/platform_device.h>

static int uhci_platform_init(struct usb_hcd *hcd)
{
 struct uhci_hcd *uhci = hcd_to_uhci(hcd);

 /* Probe number of ports if not already provided by DT */
 if (!uhci->rh_numports)
  uhci->rh_numports = uhci_count_ports(hcd);

 /* Set up pointers to to generic functions */
 uhci->reset_hc = uhci_generic_reset_hc;
 uhci->check_and_reset_hc = uhci_generic_check_and_reset_hc;

 /* No special actions need to be taken for the functions below */
 uhci->configure_hc = NULL;
 uhci->resume_detect_interrupts_are_broken = NULL;
 uhci->global_suspend_mode_is_broken = NULL;

 /* Reset if the controller isn't already safely quiescent. */
 check_and_reset_hc(uhci);
 return 0;
}

static const struct hc_driver uhci_platform_hc_driver = {
 .description =  hcd_name,
 .product_desc =  "Generic UHCI Host Controller",
 .hcd_priv_size = sizeof(struct uhci_hcd),

 /* Generic hardware linkage */
 .irq =   uhci_irq,
 .flags =  HCD_MEMORY | HCD_DMA | HCD_USB11,

 /* Basic lifecycle operations */
 .reset =  uhci_platform_init,
 .start =  uhci_start,
#ifdef CONFIG_PM
 .pci_suspend =  NULL,
 .pci_resume =  NULL,
 .bus_suspend =  uhci_rh_suspend,
 .bus_resume =  uhci_rh_resume,
#endif
 .stop =   uhci_stop,

 .urb_enqueue =  uhci_urb_enqueue,
 .urb_dequeue =  uhci_urb_dequeue,

 .endpoint_disable = uhci_hcd_endpoint_disable,
 .get_frame_number = uhci_hcd_get_frame_number,

 .hub_status_data = uhci_hub_status_data,
 .hub_control =  uhci_hub_control,
};

static int uhci_hcd_platform_probe(struct platform_device *pdev)
{
 struct device_node *np = pdev->dev.of_node;
 struct usb_hcd *hcd;
 struct uhci_hcd *uhci;
 struct resource *res;
 int ret;

 if (usb_disabled())
  return -ENODEV;

 /*
 * Right now device-tree probed devices don't get dma_mask set.
 * Since shared usb code relies on it, set it here for now.
 * Once we have dma capability bindings this can go away.
 */
 ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 if (ret)
  return ret;

 hcd = usb_create_hcd(&uhci_platform_hc_driver, &pdev->dev,
   pdev->name);
 if (!hcd)
  return -ENOMEM;

 uhci = hcd_to_uhci(hcd);

 hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 if (IS_ERR(hcd->regs)) {
  ret = PTR_ERR(hcd->regs);
  goto err_rmr;
 }
 hcd->rsrc_start = res->start;
 hcd->rsrc_len = resource_size(res);

 uhci->regs = hcd->regs;

 /* Grab some things from the device-tree */
 if (np) {
  u32 num_ports;

  if (of_property_read_u32(np, "#ports", &num_ports) == 0) {
   uhci->rh_numports = num_ports;
   dev_info(&pdev->dev,
    "Detected %d ports from device-tree\n",
    num_ports);
  }
  if (of_device_is_compatible(np, "aspeed,ast2400-uhci") ||
      of_device_is_compatible(np, "aspeed,ast2500-uhci") ||
      of_device_is_compatible(np, "aspeed,ast2600-uhci")) {
   uhci->is_aspeed = 1;
   dev_info(&pdev->dev,
     "Enabled Aspeed implementation workarounds\n");
  }
 }

 /* Get and enable clock if any specified */
 uhci->clk = devm_clk_get_optional(&pdev->dev, NULL);
 if (IS_ERR(uhci->clk)) {
  ret = PTR_ERR(uhci->clk);
  goto err_rmr;
 }
 ret = clk_prepare_enable(uhci->clk);
 if (ret) {
  dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", ret);
  goto err_rmr;
 }

 ret = platform_get_irq(pdev, 0);
 if (ret < 0)
  goto err_clk;

 ret = usb_add_hcd(hcd, ret, IRQF_SHARED);
 if (ret)
  goto err_clk;

 device_wakeup_enable(hcd->self.controller);
 return 0;

err_clk:
 clk_disable_unprepare(uhci->clk);
err_rmr:
 usb_put_hcd(hcd);

 return ret;
}

static void uhci_hcd_platform_remove(struct platform_device *pdev)
{
 struct usb_hcd *hcd = platform_get_drvdata(pdev);
 struct uhci_hcd *uhci = hcd_to_uhci(hcd);

 clk_disable_unprepare(uhci->clk);
 usb_remove_hcd(hcd);
 usb_put_hcd(hcd);
}

/* Make sure the controller is quiescent and that we're not using it
 * any more.  This is mainly for the benefit of programs which, like kexec,
 * expect the hardware to be idle: not doing DMA or generating IRQs.
 *
 * This routine may be called in a damaged or failing kernel.  Hence we
 * do not acquire the spinlock before shutting down the controller.
 */
static void uhci_hcd_platform_shutdown(struct platform_device *op)
{
 struct usb_hcd *hcd = platform_get_drvdata(op);

 uhci_hc_died(hcd_to_uhci(hcd));
}

static const struct of_device_id platform_uhci_ids[] = {
 { .compatible = "generic-uhci", },
 { .compatible = "platform-uhci", },
 {}
};
MODULE_DEVICE_TABLE(of, platform_uhci_ids);

static struct platform_driver uhci_platform_driver = {
 .probe  = uhci_hcd_platform_probe,
 .remove  = uhci_hcd_platform_remove,
 .shutdown = uhci_hcd_platform_shutdown,
 .driver = {
  .name = "platform-uhci",
  .of_match_table = platform_uhci_ids,
 },
};