linux/drivers/usb/host/ehci-xilinx-of.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * EHCI HCD (Host Controller Driver) for USB.
   4 *
   5 * Bus Glue for Xilinx EHCI core on the of_platform bus
   6 *
   7 * Copyright (c) 2009 Xilinx, Inc.
   8 *
   9 * Based on "ehci-ppc-of.c" by Valentine Barshak <vbarshak@ru.mvista.com>
  10 * and "ehci-ppc-soc.c" by Stefan Roese <sr@denx.de>
  11 * and "ohci-ppc-of.c" by Sylvain Munaut <tnt@246tNt.com>
  12 */
  13
  14#include <linux/err.h>
  15#include <linux/signal.h>
  16
  17#include <linux/of.h>
  18#include <linux/of_platform.h>
  19#include <linux/of_address.h>
  20#include <linux/of_irq.h>
  21
  22/**
  23 * ehci_xilinx_port_handed_over - hand the port out if failed to enable it
  24 * @hcd:        Pointer to the usb_hcd device to which the host controller bound
  25 * @portnum:Port number to which the device is attached.
  26 *
  27 * This function is used as a place to tell the user that the Xilinx USB host
  28 * controller does support LS devices. And in an HS only configuration, it
  29 * does not support FS devices either. It is hoped that this can help a
  30 * confused user.
  31 *
  32 * There are cases when the host controller fails to enable the port due to,
  33 * for example, insufficient power that can be supplied to the device from
  34 * the USB bus. In those cases, the messages printed here are not helpful.
  35 */
  36static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum)
  37{
  38        dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum);
  39        if (hcd->has_tt) {
  40                dev_warn(hcd->self.controller,
  41                        "Maybe you have connected a low speed device?\n");
  42
  43                dev_warn(hcd->self.controller,
  44                        "We do not support low speed devices\n");
  45        } else {
  46                dev_warn(hcd->self.controller,
  47                        "Maybe your device is not a high speed device?\n");
  48                dev_warn(hcd->self.controller,
  49                        "The USB host controller does not support full speed "
  50                        "nor low speed devices\n");
  51                dev_warn(hcd->self.controller,
  52                        "You can reconfigure the host controller to have "
  53                        "full speed support\n");
  54        }
  55
  56        return 0;
  57}
  58
  59
  60static const struct hc_driver ehci_xilinx_of_hc_driver = {
  61        .description            = hcd_name,
  62        .product_desc           = "OF EHCI",
  63        .hcd_priv_size          = sizeof(struct ehci_hcd),
  64
  65        /*
  66         * generic hardware linkage
  67         */
  68        .irq                    = ehci_irq,
  69        .flags                  = HCD_MEMORY | HCD_USB2 | HCD_BH,
  70
  71        /*
  72         * basic lifecycle operations
  73         */
  74        .reset                  = ehci_setup,
  75        .start                  = ehci_run,
  76        .stop                   = ehci_stop,
  77        .shutdown               = ehci_shutdown,
  78
  79        /*
  80         * managing i/o requests and associated device resources
  81         */
  82        .urb_enqueue            = ehci_urb_enqueue,
  83        .urb_dequeue            = ehci_urb_dequeue,
  84        .endpoint_disable       = ehci_endpoint_disable,
  85        .endpoint_reset         = ehci_endpoint_reset,
  86
  87        /*
  88         * scheduling support
  89         */
  90        .get_frame_number       = ehci_get_frame,
  91
  92        /*
  93         * root hub support
  94         */
  95        .hub_status_data        = ehci_hub_status_data,
  96        .hub_control            = ehci_hub_control,
  97#ifdef  CONFIG_PM
  98        .bus_suspend            = ehci_bus_suspend,
  99        .bus_resume             = ehci_bus_resume,
 100#endif
 101        .relinquish_port        = NULL,
 102        .port_handed_over       = ehci_xilinx_port_handed_over,
 103
 104        .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
 105};
 106
 107/**
 108 * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller
 109 * @op:         pointer to the platform_device bound to the host controller
 110 *
 111 * This function requests resources and sets up appropriate properties for the
 112 * host controller. Because the Xilinx USB host controller can be configured
 113 * as HS only or HS/FS only, it checks the configuration in the device tree
 114 * entry, and sets an appropriate value for hcd->has_tt.
 115 */
 116static int ehci_hcd_xilinx_of_probe(struct platform_device *op)
 117{
 118        struct device_node *dn = op->dev.of_node;
 119        struct usb_hcd *hcd;
 120        struct ehci_hcd *ehci;
 121        struct resource res;
 122        int irq;
 123        int rv;
 124        int *value;
 125
 126        if (usb_disabled())
 127                return -ENODEV;
 128
 129        dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n");
 130
 131        rv = of_address_to_resource(dn, 0, &res);
 132        if (rv)
 133                return rv;
 134
 135        hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev,
 136                                "XILINX-OF USB");
 137        if (!hcd)
 138                return -ENOMEM;
 139
 140        hcd->rsrc_start = res.start;
 141        hcd->rsrc_len = resource_size(&res);
 142
 143        irq = irq_of_parse_and_map(dn, 0);
 144        if (!irq) {
 145                dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
 146                        __FILE__);
 147                rv = -EBUSY;
 148                goto err_irq;
 149        }
 150
 151        hcd->regs = devm_ioremap_resource(&op->dev, &res);
 152        if (IS_ERR(hcd->regs)) {
 153                rv = PTR_ERR(hcd->regs);
 154                goto err_irq;
 155        }
 156
 157        ehci = hcd_to_ehci(hcd);
 158
 159        /* This core always has big-endian register interface and uses
 160         * big-endian memory descriptors.
 161         */
 162        ehci->big_endian_mmio = 1;
 163        ehci->big_endian_desc = 1;
 164
 165        /* Check whether the FS support option is selected in the hardware.
 166         */
 167        value = (int *)of_get_property(dn, "xlnx,support-usb-fs", NULL);
 168        if (value && (*value == 1)) {
 169                ehci_dbg(ehci, "USB host controller supports FS devices\n");
 170                hcd->has_tt = 1;
 171        } else {
 172                ehci_dbg(ehci,
 173                        "USB host controller is HS only\n");
 174                hcd->has_tt = 0;
 175        }
 176
 177        /* Debug registers are at the first 0x100 region
 178         */
 179        ehci->caps = hcd->regs + 0x100;
 180
 181        rv = usb_add_hcd(hcd, irq, 0);
 182        if (rv == 0) {
 183                device_wakeup_enable(hcd->self.controller);
 184                return 0;
 185        }
 186
 187err_irq:
 188        usb_put_hcd(hcd);
 189
 190        return rv;
 191}
 192
 193/**
 194 * ehci_hcd_xilinx_of_remove - shutdown hcd and release resources
 195 * @op:         pointer to platform_device structure that is to be removed
 196 *
 197 * Remove the hcd structure, and release resources that has been requested
 198 * during probe.
 199 */
 200static int ehci_hcd_xilinx_of_remove(struct platform_device *op)
 201{
 202        struct usb_hcd *hcd = platform_get_drvdata(op);
 203
 204        dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n");
 205
 206        usb_remove_hcd(hcd);
 207
 208        usb_put_hcd(hcd);
 209
 210        return 0;
 211}
 212
 213static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
 214                {.compatible = "xlnx,xps-usb-host-1.00.a",},
 215        {},
 216};
 217MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
 218
 219static struct platform_driver ehci_hcd_xilinx_of_driver = {
 220        .probe          = ehci_hcd_xilinx_of_probe,
 221        .remove         = ehci_hcd_xilinx_of_remove,
 222        .shutdown       = usb_hcd_platform_shutdown,
 223        .driver = {
 224                .name = "xilinx-of-ehci",
 225                .of_match_table = ehci_hcd_xilinx_of_match,
 226        },
 227};
 228