source: mainline/uspace/drv/bus/usb/xhci/bus.c@ f92f6b1

/*
 * Copyright (c) 2017 Ondrej Hlavaty <aearsis@eideo.cz>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/**  @addtogroup libusbhost
 * @{
 */
/** @file
 * HC Endpoint management.
 */

#include <usb/host/ddf_helpers.h>
#include <usb/host/endpoint.h>
#include <usb/host/hcd.h>
#include <usb/descriptor.h>
#include <usb/debug.h>

#include <assert.h>
#include <errno.h>
#include <str_error.h>
#include <macros.h>
#include <stdbool.h>

#include "hc.h"
#include "bus.h"
#include "endpoint.h"
#include "transfers.h"


/** Initial descriptor used for control endpoint 0 before more configuration is retrieved. */
static const usb_endpoint_descriptors_t ep0_initial_desc = {
        .endpoint.max_packet_size = CTRL_PIPE_MIN_PACKET_SIZE,
};

static endpoint_t *endpoint_create(device_t *, const usb_endpoint_descriptors_t *);

/**
 * Assign address and control endpoint to a new XHCI device. Once this function
 * successfully returns, the device is online.
 *
 * @param[in] bus XHCI bus, in which the address is assigned.
 * @param[in] dev New device to address and configure./e
 * @return Error code.
 */
static int address_device(xhci_bus_t *bus, xhci_device_t *dev)
{
        int err;

        /* Enable new slot. */
        if ((err = hc_enable_slot(bus->hc, &dev->slot_id)) != EOK)
                return err;
        usb_log_debug2("Obtained slot ID: %u.\n", dev->slot_id);

        /* Create and configure control endpoint. */
        endpoint_t *ep0_base = endpoint_create(&dev->base, &ep0_initial_desc);
        if (!ep0_base)
                goto err_slot;

        /* Bus reference */
        endpoint_add_ref(ep0_base);
        dev->base.endpoints[0] = ep0_base;

        xhci_endpoint_t *ep0 = xhci_endpoint_get(ep0_base);

        /* Address device */
        if ((err = hc_address_device(bus->hc, dev, ep0)))
                goto err_added;

        return EOK;

err_added:
        /* Bus reference */
        endpoint_del_ref(ep0_base);
        dev->base.endpoints[0] = NULL;
err_slot:
        hc_disable_slot(bus->hc, dev);
        return err;
}

/**
 * Retrieve and set maximum packet size for endpoint zero of a XHCI device.
 *
 * @param[in] hc Host controller, which manages the device.
 * @param[in] dev Device with operational endpoint zero.
 * @return Error code.
 */
static int setup_ep0_packet_size(xhci_hc_t *hc, xhci_device_t *dev)
{
        int err;

        uint16_t max_packet_size;
        if ((err = hcd_get_ep0_max_packet_size(&max_packet_size, (bus_t *) &hc->bus, &dev->base)))
                return err;

        xhci_endpoint_t *ep0 = xhci_device_get_endpoint(dev, 0);
        assert(ep0);

        if (ep0->base.max_packet_size == max_packet_size)
                return EOK;

        ep0->base.max_packet_size = max_packet_size;
        ep0->base.max_transfer_size = max_packet_size * ep0->base.packets_per_uframe;

        xhci_ep_ctx_t ep_ctx;
        xhci_setup_endpoint_context(ep0, &ep_ctx);

        if ((err = hc_update_endpoint(hc, dev->slot_id, 0, &ep_ctx)))
                return err;

        return EOK;
}

/**
 * Respond to a new device on the XHCI bus. Address it, negotiate packet size
 * and retrieve USB descriptors.
 *
 * @param[in] bus XHCI bus, where the new device emerged.
 * @param[in] dev XHCI device, which has appeared on the bus.
 *
 * @return Error code.
 */
static int device_enumerate(device_t *dev)
{
        int err;
        xhci_bus_t *bus = bus_to_xhci_bus(dev->bus);
        xhci_device_t *xhci_dev = xhci_device_get(dev);

        hcd_setup_device_tt(dev);

        /* Calculate route string */
        xhci_device_t *xhci_hub = xhci_device_get(dev->hub);
        xhci_dev->tier = xhci_hub->tier + 1;
        xhci_dev->route_str = xhci_hub->route_str;

        /* Roothub port is not part of the route string */
        if (xhci_dev->tier >= 2) {
                const unsigned offset = 4 * (xhci_dev->tier - 2);
                xhci_dev->route_str |= (dev->port & 0xf) << offset;
                xhci_dev->rh_port = xhci_hub->rh_port;
        }

        /* Assign an address to the device */
        if ((err = address_device(bus, xhci_dev))) {
                usb_log_error("Failed to setup address of the new device: %s", str_error(err));
                return err;
        }

        /* Setup EP0 might already need to issue a transfer. */
        fibril_mutex_lock(&bus->base.guard);
        assert(bus->devices_by_slot[xhci_dev->slot_id] == NULL);
        bus->devices_by_slot[xhci_dev->slot_id] = xhci_dev;
        fibril_mutex_unlock(&bus->base.guard);

        if ((err = setup_ep0_packet_size(bus->hc, xhci_dev))) {
                usb_log_error("Failed to setup control endpoint of the new device: %s", str_error(err));
                goto err_address;
        }

        /* Read the device descriptor, derive the match ids */
        if ((err = hcd_device_explore(dev))) {
                usb_log_error("Device(%d): Failed to explore device: %s", dev->address, str_error(err));
                goto err_address;
        }

        return EOK;

err_address:
        // TODO: deaddress device
        return err;
}

static int endpoint_unregister(endpoint_t *);

/**
 * Remove device from XHCI bus. Transition it to the offline state, abort all
 * ongoing transfers and unregister all of its endpoints.
 *
 * Bus callback.
 *
 * @param[in] bus XHCI bus, from which the device is removed.
 * @param[in] dev XHCI device, which is removed from the bus.
 * @return Error code.
 */
static int device_remove(device_t *dev)
{
        int err;
        xhci_bus_t *bus = bus_to_xhci_bus(dev->bus);
        xhci_device_t *xhci_dev = xhci_device_get(dev);

        /* Block creation of new endpoints and transfers. */
        usb_log_debug2("Device " XHCI_DEV_FMT " going offline.", XHCI_DEV_ARGS(*xhci_dev));
        fibril_mutex_lock(&dev->guard);
        dev->online = false;
        fibril_mutex_unlock(&dev->guard);

        /* Abort running transfers. */
        usb_log_debug2("Aborting all active transfers to device " XHCI_DEV_FMT ".", XHCI_DEV_ARGS(*xhci_dev));
        for (usb_endpoint_t i = 0; i < USB_ENDPOINT_MAX; ++i) {
                xhci_endpoint_t *ep = xhci_device_get_endpoint(xhci_dev, i);
                if (!ep)
                        continue;

                endpoint_abort(&ep->base);
        }

        /* TODO: Figure out how to handle errors here. So far, they are reported and skipped. */

        /* Make DDF (and all drivers) forget about the device. */
        if ((err = ddf_fun_unbind(dev->fun))) {
                usb_log_warning("Failed to unbind DDF function of device " XHCI_DEV_FMT ": %s",
                    XHCI_DEV_ARGS(*xhci_dev), str_error(err));
        }

        /* Disable the slot, dropping all endpoints. */
        const uint32_t slot_id = xhci_dev->slot_id;
        if ((err = hc_disable_slot(bus->hc, xhci_dev))) {
                usb_log_warning("Failed to disable slot of device " XHCI_DEV_FMT ": %s",
                    XHCI_DEV_ARGS(*xhci_dev), str_error(err));
        }

        bus->devices_by_slot[slot_id] = NULL;

        /* Unregister remaining endpoints, freeing memory. */
        for (usb_endpoint_t i = 0; i < USB_ENDPOINT_MAX; ++i) {
                if (!dev->endpoints[i])
                        continue;

                if ((err = endpoint_unregister(dev->endpoints[i]))) {
                        usb_log_warning("Failed to unregister endpoint " XHCI_EP_FMT ": %s",
                            XHCI_EP_ARGS(*xhci_device_get_endpoint(xhci_dev, i)), str_error(err));
                }
        }

        /* Destroy DDF device. */
        /* XXX: Not a good idea, this method should not destroy devices. */
        hcd_ddf_fun_destroy(dev);

        return EOK;
}

/**
 * Reverts things device_offline did, getting the device back up.
 *
 * Bus callback.
 */
static int device_online(device_t *dev_base)
{
        int err;

        xhci_bus_t *bus = bus_to_xhci_bus(dev_base->bus);
        assert(bus);

        xhci_device_t *dev = xhci_device_get(dev_base);
        assert(dev);

        /* Transition the device from the Addressed to the Configured state. */
        if ((err = hc_configure_device(bus->hc, dev->slot_id))) {
                usb_log_warning("Failed to configure device " XHCI_DEV_FMT ".", XHCI_DEV_ARGS(*dev));
        }

        /* Allow creation of new endpoints and transfers. */
        usb_log_debug2("Device " XHCI_DEV_FMT " going online.", XHCI_DEV_ARGS(*dev));
        fibril_mutex_lock(&dev_base->guard);
        dev_base->online = true;
        fibril_mutex_unlock(&dev_base->guard);

        if ((err = ddf_fun_online(dev_base->fun))) {
                return err;
        }

        return EOK;
}

/**
 * Make given device offline. Offline the DDF function, tear down all
 * endpoints, issue Deconfigure Device command to xHC.
 *
 * Bus callback.
 */
static int device_offline(device_t *dev_base)
{
        int err;

        xhci_bus_t *bus = bus_to_xhci_bus(dev_base->bus);
        assert(bus);

        xhci_device_t *dev = xhci_device_get(dev_base);
        assert(dev);

        /* Tear down all drivers working with the device. */
        if ((err = ddf_fun_offline(dev_base->fun))) {
                return err;
        }

        /* Block creation of new endpoints and transfers. */
        usb_log_debug2("Device " XHCI_DEV_FMT " going offline.", XHCI_DEV_ARGS(*dev));
        fibril_mutex_lock(&dev_base->guard);
        dev_base->online = false;
        fibril_mutex_unlock(&dev_base->guard);

        /* We will need the endpoint array later for DS deallocation. */
        endpoint_t *endpoints[USB_ENDPOINT_MAX];
        memcpy(endpoints, dev->base.endpoints, sizeof(endpoints));

        for (usb_endpoint_t i = 1; i < USB_ENDPOINT_MAX; ++i) {
                /* FIXME: Asserting here that the endpoint is not active. If not, EBUSY? */
                dev->base.endpoints[i] = NULL;
        }

        /* Issue one HC command to simultaneously drop all endpoints except zero. */
        if ((err = hc_deconfigure_device(bus->hc, dev->slot_id))) {
                usb_log_warning("Failed to deconfigure device " XHCI_DEV_FMT ".",
                    XHCI_DEV_ARGS(*dev));
        }

        /* Tear down TRB ring / PSA. */
        for (unsigned i = 1; i < ARRAY_SIZE(endpoints); ++i) {
                if (!endpoints[i])
                        continue;

                /* Bus reference */
                endpoint_del_ref(endpoints[i]);
        }

        return EOK;
}

/**
 * Create a new xHCI endpoint structure.
 *
 * Bus callback.
 */
static endpoint_t *endpoint_create(device_t *dev, const usb_endpoint_descriptors_t *desc)
{
        const usb_transfer_type_t type = USB_ED_GET_TRANSFER_TYPE(desc->endpoint);

        xhci_endpoint_t *ep = calloc(1, sizeof(xhci_endpoint_t)
                + (type == USB_TRANSFER_ISOCHRONOUS) * sizeof(*ep->isoch));
        if (!ep)
                return NULL;

        if (xhci_endpoint_init(ep, dev, desc)) {
                free(ep);
                return NULL;
        }

        return &ep->base;
}

/**
 * Destroy given xHCI endpoint structure.
 *
 * Bus callback.
 */
static void endpoint_destroy(endpoint_t *ep)
{
        xhci_endpoint_t *xhci_ep = xhci_endpoint_get(ep);

        xhci_endpoint_fini(xhci_ep);
        free(xhci_ep);
}

/**
 * Register an andpoint to the bus. Allocate its transfer ring(s) and inform
 * xHC about it.
 *
 * Bus callback.
 */
static int endpoint_register(endpoint_t *ep_base)
{
        int err;
        xhci_bus_t *bus = bus_to_xhci_bus(endpoint_get_bus(ep_base));
        xhci_endpoint_t *ep = xhci_endpoint_get(ep_base);

        xhci_device_t *dev = xhci_device_get(ep_base->device);

        usb_log_info("Endpoint " XHCI_EP_FMT " registered to XHCI bus.", XHCI_EP_ARGS(*ep));

        xhci_ep_ctx_t ep_ctx;
        xhci_setup_endpoint_context(ep, &ep_ctx);

        if ((err = hc_add_endpoint(bus->hc, dev->slot_id, xhci_endpoint_index(ep), &ep_ctx)))
                return err;

        return EOK;
}

/**
 * Unregister an endpoint. If the device is still available, inform the xHC
 * about it. Destroy resources allocated when registering.
 *
 * Bus callback.
 */
static int endpoint_unregister(endpoint_t *ep_base)
{
        int err;
        xhci_bus_t *bus = bus_to_xhci_bus(endpoint_get_bus(ep_base));
        xhci_endpoint_t *ep = xhci_endpoint_get(ep_base);
        xhci_device_t *dev = xhci_device_get(ep_base->device);

        usb_log_info("Endpoint " XHCI_EP_FMT " unregistered from XHCI bus.", XHCI_EP_ARGS(*ep));

        /* If device slot is still available, drop the endpoint. */
        if (dev->slot_id) {
                if ((err = hc_drop_endpoint(bus->hc, dev->slot_id, xhci_endpoint_index(ep)))) {
                        usb_log_error("Failed to drop endpoint " XHCI_EP_FMT ": %s", XHCI_EP_ARGS(*ep), str_error(err));
                }
        } else {
                usb_log_debug("Not going to drop endpoint " XHCI_EP_FMT " because"
                    " the slot has already been disabled.", XHCI_EP_ARGS(*ep));
        }

        return EOK;
}

/**
 * Schedule a batch for xHC.
 *
 * Bus callback.
 */
static int batch_schedule(usb_transfer_batch_t *batch)
{
        assert(batch);
        xhci_hc_t *hc = bus_to_hc(endpoint_get_bus(batch->ep));

        if (!batch->target.address) {
                usb_log_error("Attempted to schedule transfer to address 0.");
                return EINVAL;
        }

        return xhci_transfer_schedule(hc, batch);
}

static const bus_ops_t xhci_bus_ops = {
        .interrupt = hc_interrupt,
        .status = hc_status,

        .device_enumerate = device_enumerate,
        .device_remove = device_remove,
        .device_online = device_online,
        .device_offline = device_offline,

        .endpoint_create = endpoint_create,
        .endpoint_destroy = endpoint_destroy,
        .endpoint_register = endpoint_register,
        .endpoint_unregister = endpoint_unregister,

        .batch_schedule = batch_schedule,
        .batch_create = xhci_transfer_create,
        .batch_destroy = xhci_transfer_destroy,
};

/** Initialize XHCI bus.
 * @param[in] bus Allocated XHCI bus to initialize.
 * @param[in] hc Associated host controller, which manages the bus.
 *
 * @return Error code.
 */
int xhci_bus_init(xhci_bus_t *bus, xhci_hc_t *hc)
{
        assert(bus);

        bus_init(&bus->base, sizeof(xhci_device_t));

        bus->devices_by_slot = calloc(hc->max_slots, sizeof(xhci_device_t *));
        if (!bus->devices_by_slot)
                return ENOMEM;

        bus->hc = hc;
        bus->base.ops = &xhci_bus_ops;
        return EOK;
}

/** Finalize XHCI bus.
 * @param[in] bus XHCI bus to finalize.
 */
void xhci_bus_fini(xhci_bus_t *bus)
{
        // FIXME: Ensure there are no more devices?
        free(bus->devices_by_slot);
        // FIXME: Something else we forgot?
}

/**
 * @}
 */