usb/host/ehci-xilinx-of.c

0001 // SPDX-License-Identifier: GPL-2.0+
0002 /*
0003  * EHCI HCD (Host Controller Driver) for USB.
0004  *
0005  * Bus Glue for Xilinx EHCI core on the of_platform bus
0006  *
0007  * Copyright (c) 2009 Xilinx, Inc.
0008  *
0009  * Based on "ehci-ppc-of.c" by Valentine Barshak <vbarshak@ru.mvista.com>
0010  * and "ehci-ppc-soc.c" by Stefan Roese <sr@denx.de>
0011  * and "ohci-ppc-of.c" by Sylvain Munaut <tnt@246tNt.com>
0012  */
0013
0014 #include <linux/err.h>
0015 #include <linux/signal.h>
0016
0017 #include <linux/of.h>
0018 #include <linux/of_platform.h>
0019 #include <linux/of_address.h>
0020 #include <linux/of_irq.h>
0021
0022 /**
0023  * ehci_xilinx_port_handed_over - hand the port out if failed to enable it
0024  * @hcd:    Pointer to the usb_hcd device to which the host controller bound
0025  * @portnum:Port number to which the device is attached.
0026  *
0027  * This function is used as a place to tell the user that the Xilinx USB host
0028  * controller does support LS devices. And in an HS only configuration, it
0029  * does not support FS devices either. It is hoped that this can help a
0030  * confused user.
0031  *
0032  * There are cases when the host controller fails to enable the port due to,
0033  * for example, insufficient power that can be supplied to the device from
0034  * the USB bus. In those cases, the messages printed here are not helpful.
0035  *
0036  * Return: Always return 0
0037  */
0038 static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum)
0039 {
0040     dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum);
0041     if (hcd->has_tt) {
0042         dev_warn(hcd->self.controller,
0043             "Maybe you have connected a low speed device?\n");
0044
0045         dev_warn(hcd->self.controller,
0046             "We do not support low speed devices\n");
0047     } else {
0048         dev_warn(hcd->self.controller,
0049             "Maybe your device is not a high speed device?\n");
0050         dev_warn(hcd->self.controller,
0051             "The USB host controller does not support full speed nor low speed devices\n");
0052         dev_warn(hcd->self.controller,
0053             "You can reconfigure the host controller to have full speed support\n");
0054     }
0055
0056     return 0;
0057 }
0058
0059
0060 static const struct hc_driver ehci_xilinx_of_hc_driver = {
0061     .description        = hcd_name,
0062     .product_desc       = "OF EHCI",
0063     .hcd_priv_size      = sizeof(struct ehci_hcd),
0064
0065     /*
0066      * generic hardware linkage
0067      */
0068     .irq            = ehci_irq,
0069     .flags          = HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,
0070
0071     /*
0072      * basic lifecycle operations
0073      */
0074     .reset          = ehci_setup,
0075     .start          = ehci_run,
0076     .stop           = ehci_stop,
0077     .shutdown       = ehci_shutdown,
0078
0079     /*
0080      * managing i/o requests and associated device resources
0081      */
0082     .urb_enqueue        = ehci_urb_enqueue,
0083     .urb_dequeue        = ehci_urb_dequeue,
0084     .endpoint_disable   = ehci_endpoint_disable,
0085     .endpoint_reset     = ehci_endpoint_reset,
0086
0087     /*
0088      * scheduling support
0089      */
0090     .get_frame_number   = ehci_get_frame,
0091
0092     /*
0093      * root hub support
0094      */
0095     .hub_status_data    = ehci_hub_status_data,
0096     .hub_control        = ehci_hub_control,
0097 #ifdef  CONFIG_PM
0098     .bus_suspend        = ehci_bus_suspend,
0099     .bus_resume     = ehci_bus_resume,
0100 #endif
0101     .relinquish_port    = NULL,
0102     .port_handed_over   = ehci_xilinx_port_handed_over,
0103
0104     .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
0105 };
0106
0107 /**
0108  * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller
0109  * @op:     pointer to the platform_device bound to the host controller
0110  *
0111  * This function requests resources and sets up appropriate properties for the
0112  * host controller. Because the Xilinx USB host controller can be configured
0113  * as HS only or HS/FS only, it checks the configuration in the device tree
0114  * entry, and sets an appropriate value for hcd->has_tt.
0115  *
0116  * Return: zero on success, negative error code otherwise
0117  */
0118 static int ehci_hcd_xilinx_of_probe(struct platform_device *op)
0119 {
0120     struct device_node *dn = op->dev.of_node;
0121     struct usb_hcd *hcd;
0122     struct ehci_hcd *ehci;
0123     struct resource res;
0124     int irq;
0125     int rv;
0126     int *value;
0127
0128     if (usb_disabled())
0129         return -ENODEV;
0130
0131     dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n");
0132
0133     rv = of_address_to_resource(dn, 0, &res);
0134     if (rv)
0135         return rv;
0136
0137     hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev,
0138                 "XILINX-OF USB");
0139     if (!hcd)
0140         return -ENOMEM;
0141
0142     hcd->rsrc_start = res.start;
0143     hcd->rsrc_len = resource_size(&res);
0144
0145     irq = irq_of_parse_and_map(dn, 0);
0146     if (!irq) {
0147         dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
0148             __FILE__);
0149         rv = -EBUSY;
0150         goto err_irq;
0151     }
0152
0153     hcd->regs = devm_ioremap_resource(&op->dev, &res);
0154     if (IS_ERR(hcd->regs)) {
0155         rv = PTR_ERR(hcd->regs);
0156         goto err_irq;
0157     }
0158
0159     ehci = hcd_to_ehci(hcd);
0160
0161     /* This core always has big-endian register interface and uses
0162      * big-endian memory descriptors.
0163      */
0164     ehci->big_endian_mmio = 1;
0165     ehci->big_endian_desc = 1;
0166
0167     /* Check whether the FS support option is selected in the hardware.
0168      */
0169     value = (int *)of_get_property(dn, "xlnx,support-usb-fs", NULL);
0170     if (value && (*value == 1)) {
0171         ehci_dbg(ehci, "USB host controller supports FS devices\n");
0172         hcd->has_tt = 1;
0173     } else {
0174         ehci_dbg(ehci,
0175             "USB host controller is HS only\n");
0176         hcd->has_tt = 0;
0177     }
0178
0179     /* Debug registers are at the first 0x100 region
0180      */
0181     ehci->caps = hcd->regs + 0x100;
0182
0183     rv = usb_add_hcd(hcd, irq, 0);
0184     if (rv == 0) {
0185         device_wakeup_enable(hcd->self.controller);
0186         return 0;
0187     }
0188
0189 err_irq:
0190     usb_put_hcd(hcd);
0191
0192     return rv;
0193 }
0194
0195 /**
0196  * ehci_hcd_xilinx_of_remove - shutdown hcd and release resources
0197  * @op:     pointer to platform_device structure that is to be removed
0198  *
0199  * Remove the hcd structure, and release resources that has been requested
0200  * during probe.
0201  *
0202  * Return: Always return 0
0203  */
0204 static int ehci_hcd_xilinx_of_remove(struct platform_device *op)
0205 {
0206     struct usb_hcd *hcd = platform_get_drvdata(op);
0207
0208     dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n");
0209
0210     usb_remove_hcd(hcd);
0211
0212     usb_put_hcd(hcd);
0213
0214     return 0;
0215 }
0216
0217 static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
0218         {.compatible = "xlnx,xps-usb-host-1.00.a",},
0219     {},
0220 };
0221 MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
0222
0223 static struct platform_driver ehci_hcd_xilinx_of_driver = {
0224     .probe      = ehci_hcd_xilinx_of_probe,
0225     .remove     = ehci_hcd_xilinx_of_remove,
0226     .shutdown   = usb_hcd_platform_shutdown,
0227     .driver = {
0228         .name = "xilinx-of-ehci",
0229         .of_match_table = ehci_hcd_xilinx_of_match,
0230     },
0231 };