root/drivers/usb/host/ohci-ppc-of.c
// SPDX-License-Identifier: GPL-1.0+
/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
 * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
 * (C) Copyright 2002 Hewlett-Packard Company
 * (C) Copyright 2006 Sylvain Munaut <tnt@246tNt.com>
 *
 * Bus glue for OHCI HC on the of_platform bus
 *
 * Modified for of_platform bus from ohci-sa1111.c
 *
 * This file is licenced under the GPL.
 */

#include <linux/signal.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>

static int
ohci_ppc_of_start(struct usb_hcd *hcd)
{
        struct ohci_hcd *ohci = hcd_to_ohci(hcd);
        int             ret;

        if ((ret = ohci_init(ohci)) < 0)
                return ret;

        if ((ret = ohci_run(ohci)) < 0) {
                dev_err(hcd->self.controller, "can't start %s\n",
                        hcd->self.bus_name);
                ohci_stop(hcd);
                return ret;
        }

        return 0;
}

static const struct hc_driver ohci_ppc_of_hc_driver = {
        .description =          hcd_name,
        .product_desc =         "OF OHCI",
        .hcd_priv_size =        sizeof(struct ohci_hcd),

        /*
         * generic hardware linkage
         */
        .irq =                  ohci_irq,
        .flags =                HCD_USB11 | HCD_DMA | HCD_MEMORY,

        /*
         * basic lifecycle operations
         */
        .start =                ohci_ppc_of_start,
        .stop =                 ohci_stop,
        .shutdown =             ohci_shutdown,

        /*
         * managing i/o requests and associated device resources
         */
        .urb_enqueue =          ohci_urb_enqueue,
        .urb_dequeue =          ohci_urb_dequeue,
        .endpoint_disable =     ohci_endpoint_disable,

        /*
         * scheduling support
         */
        .get_frame_number =     ohci_get_frame,

        /*
         * root hub support
         */
        .hub_status_data =      ohci_hub_status_data,
        .hub_control =          ohci_hub_control,
#ifdef  CONFIG_PM
        .bus_suspend =          ohci_bus_suspend,
        .bus_resume =           ohci_bus_resume,
#endif
        .start_port_reset =     ohci_start_port_reset,
};


static int ohci_hcd_ppc_of_probe(struct platform_device *op)
{
        struct device_node *dn = op->dev.of_node;
        struct usb_hcd *hcd;
        struct ohci_hcd *ohci;
        struct resource res;
        int irq;

        int rv;
        int is_bigendian;
        struct device_node *np;

        if (usb_disabled())
                return -ENODEV;

        is_bigendian =
                of_device_is_compatible(dn, "ohci-bigendian") ||
                of_device_is_compatible(dn, "ohci-be");

        dev_dbg(&op->dev, "initializing PPC-OF USB Controller\n");

        rv = of_address_to_resource(dn, 0, &res);
        if (rv)
                return rv;

        hcd = usb_create_hcd(&ohci_ppc_of_hc_driver, &op->dev, "PPC-OF USB");
        if (!hcd)
                return -ENOMEM;

        hcd->rsrc_start = res.start;
        hcd->rsrc_len = resource_size(&res);

        hcd->regs = devm_ioremap_resource(&op->dev, &res);
        if (IS_ERR(hcd->regs)) {
                rv = PTR_ERR(hcd->regs);
                goto err_rmr;
        }

        irq = irq_of_parse_and_map(dn, 0);
        if (!irq) {
                dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
                        __FILE__);
                rv = -EBUSY;
                goto err_rmr;
        }

        ohci = hcd_to_ohci(hcd);
        if (is_bigendian) {
                ohci->flags |= OHCI_QUIRK_BE_MMIO | OHCI_QUIRK_BE_DESC;
                if (of_device_is_compatible(dn, "fsl,mpc5200-ohci"))
                        ohci->flags |= OHCI_QUIRK_FRAME_NO;
                if (of_device_is_compatible(dn, "mpc5200-ohci"))
                        ohci->flags |= OHCI_QUIRK_FRAME_NO;
        }

        ohci_hcd_init(ohci);

        rv = usb_add_hcd(hcd, irq, 0);
        if (rv == 0) {
                device_wakeup_enable(hcd->self.controller);
                return 0;
        }

        /* by now, 440epx is known to show usb_23 erratum */
        np = of_find_compatible_node(NULL, NULL, "ibm,usb-ehci-440epx");

        /* Work around - At this point ohci_run has executed, the
        * controller is running, everything, the root ports, etc., is
        * set up.  If the ehci driver is loaded, put the ohci core in
        * the suspended state.  The ehci driver will bring it out of
        * suspended state when / if a non-high speed USB device is
        * attached to the USB Host port.  If the ehci driver is not
        * loaded, do nothing. request_mem_region is used to test if
        * the ehci driver is loaded.
        */
        if (np !=  NULL) {
                if (!of_address_to_resource(np, 0, &res)) {
                        if (!request_mem_region(res.start, 0x4, hcd_name)) {
                                writel_be((readl_be(&ohci->regs->control) |
                                        OHCI_USB_SUSPEND), &ohci->regs->control);
                                        (void) readl_be(&ohci->regs->control);
                        } else
                                release_mem_region(res.start, 0x4);
                } else
                        pr_debug("%s: cannot get ehci offset from fdt\n", __FILE__);
                of_node_put(np);
        }

        irq_dispose_mapping(irq);
err_rmr:
        usb_put_hcd(hcd);

        return rv;
}

static void ohci_hcd_ppc_of_remove(struct platform_device *op)
{
        struct usb_hcd *hcd = platform_get_drvdata(op);

        dev_dbg(&op->dev, "stopping PPC-OF USB Controller\n");

        usb_remove_hcd(hcd);

        irq_dispose_mapping(hcd->irq);

        usb_put_hcd(hcd);
}

static const struct of_device_id ohci_hcd_ppc_of_match[] = {
#ifdef CONFIG_USB_OHCI_HCD_PPC_OF_BE
        {
                .name = "usb",
                .compatible = "ohci-bigendian",
        },
        {
                .name = "usb",
                .compatible = "ohci-be",
        },
#endif
#ifdef CONFIG_USB_OHCI_HCD_PPC_OF_LE
        {
                .name = "usb",
                .compatible = "ohci-le",
        },
#endif
        {},
};
MODULE_DEVICE_TABLE(of, ohci_hcd_ppc_of_match);

#if     !defined(CONFIG_USB_OHCI_HCD_PPC_OF_BE) && \
        !defined(CONFIG_USB_OHCI_HCD_PPC_OF_LE)
#error "No endianness selected for ppc-of-ohci"
#endif


static struct platform_driver ohci_hcd_ppc_of_driver = {
        .probe          = ohci_hcd_ppc_of_probe,
        .remove         = ohci_hcd_ppc_of_remove,
        .shutdown       = usb_hcd_platform_shutdown,
        .driver = {
                .name = "ppc-of-ohci",
                .of_match_table = ohci_hcd_ppc_of_match,
        },
};