drivers/usb/host/ehci-xilinx-of.c

   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  */
  36 static 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
  60 static 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  */
 116 static 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
 187 err_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  */
 200 static 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
 213 static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
 214                 {.compatible = "xlnx,xps-usb-host-1.00.a",},
 215         {},
 216 };
 217 MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
 218
 219 static 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 };