wusbhc.c

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/*
 * Wireless USB Host Controller
 * sysfs glue, wusbcore module support and life cycle management
 *
 *
 * Copyright (C) 2005-2006 Intel Corporation
 * Inaky Perez-Gonzalez <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 *
 * Creation/destruction of wusbhc is split in two parts; that that
 * doesn't require the HCD to be added (wusbhc_{create,destroy}) and
 * the one that requires (phase B, wusbhc_b_{create,destroy}).
 *
 * This is so because usb_add_hcd() will start the HC, and thus, all
 * the HC specific stuff has to be already initialized (like sysfs
 * thingies).
 */
#include <linux/device.h>
#include <linux/module.h>
#include "wusbhc.h"

static struct wusbhc *usbhc_dev_to_wusbhc(struct device *dev)
{
    struct usb_bus *usb_bus = dev_get_drvdata(dev);
    struct usb_hcd *usb_hcd = bus_to_hcd(usb_bus);
    return usb_hcd_to_wusbhc(usb_hcd);
}

/*
 * Show & store the current WUSB trust timeout
 *
 * We don't do locking--it is an 'atomic' value.
 *
 * The units that we store/show are always MILLISECONDS. However, the
 * value of trust_timeout is jiffies.
 */
static ssize_t wusb_trust_timeout_show(struct device *dev,
                       struct device_attribute *attr, char *buf)
{
    struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);

    return scnprintf(buf, PAGE_SIZE, "%u\n", wusbhc->trust_timeout);
}

static ssize_t wusb_trust_timeout_store(struct device *dev,
                    struct device_attribute *attr,
                    const char *buf, size_t size)
{
    struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
    ssize_t result = -ENOSYS;
    unsigned trust_timeout;

    result = sscanf(buf, "%u", &trust_timeout);
    if (result != 1) {
        result = -EINVAL;
        goto out;
    }
    /* FIXME: maybe we should check for range validity? */
    wusbhc->trust_timeout = trust_timeout;
    cancel_delayed_work(&wusbhc->keep_alive_timer);
    flush_workqueue(wusbd);
    queue_delayed_work(wusbd, &wusbhc->keep_alive_timer,
               (trust_timeout * CONFIG_HZ)/1000/2);
out:
    return result < 0 ? result : size;
}
static DEVICE_ATTR(wusb_trust_timeout, 0644, wusb_trust_timeout_show,
                         wusb_trust_timeout_store);

/*
 * Show the current WUSB CHID.
 */
static ssize_t wusb_chid_show(struct device *dev,
                  struct device_attribute *attr, char *buf)
{
    struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
    const struct wusb_ckhdid *chid;
    ssize_t result = 0;

    if (wusbhc->wuie_host_info != NULL)
        chid = &wusbhc->wuie_host_info->CHID;
    else
        chid = &wusb_ckhdid_zero;

    result += ckhdid_printf(buf, PAGE_SIZE, chid);
    result += sprintf(buf + result, "\n");

    return result;
}

/*
 * Store a new CHID.
 *
 * - Write an all zeros CHID and it will stop the controller
 * - Write a non-zero CHID and it will start it.
 *
 * See wusbhc_chid_set() for more info.
 */
static ssize_t wusb_chid_store(struct device *dev,
                   struct device_attribute *attr,
                   const char *buf, size_t size)
{
    struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
    struct wusb_ckhdid chid;
    ssize_t result;

    result = sscanf(buf,
            "%02hhx %02hhx %02hhx %02hhx "
            "%02hhx %02hhx %02hhx %02hhx "
            "%02hhx %02hhx %02hhx %02hhx "
            "%02hhx %02hhx %02hhx %02hhx\n",
            &chid.data[0] , &chid.data[1] ,
            &chid.data[2] , &chid.data[3] ,
            &chid.data[4] , &chid.data[5] ,
            &chid.data[6] , &chid.data[7] ,
            &chid.data[8] , &chid.data[9] ,
            &chid.data[10], &chid.data[11],
            &chid.data[12], &chid.data[13],
            &chid.data[14], &chid.data[15]);
    if (result != 16) {
        dev_err(dev, "Unrecognized CHID (need 16 8-bit hex digits): "
            "%d\n", (int)result);
        return -EINVAL;
    }
    result = wusbhc_chid_set(wusbhc, &chid);
    return result < 0 ? result : size;
}
static DEVICE_ATTR(wusb_chid, 0644, wusb_chid_show, wusb_chid_store);


static ssize_t wusb_phy_rate_show(struct device *dev,
                  struct device_attribute *attr,
                  char *buf)
{
    struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);

    return sprintf(buf, "%d\n", wusbhc->phy_rate);
}

static ssize_t wusb_phy_rate_store(struct device *dev,
                   struct device_attribute *attr,
                   const char *buf, size_t size)
{
    struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
    uint8_t phy_rate;
    ssize_t result;

    result = sscanf(buf, "%hhu", &phy_rate);
    if (result != 1)
        return -EINVAL;
    if (phy_rate >= UWB_PHY_RATE_INVALID)
        return -EINVAL;

    wusbhc->phy_rate = phy_rate;
    return size;
}
static DEVICE_ATTR(wusb_phy_rate, 0644, wusb_phy_rate_show, wusb_phy_rate_store);

/* Group all the WUSBHC attributes */
static struct attribute *wusbhc_attrs[] = {
        &dev_attr_wusb_trust_timeout.attr,
        &dev_attr_wusb_chid.attr,
        &dev_attr_wusb_phy_rate.attr,
        NULL,
};

static struct attribute_group wusbhc_attr_group = {
    .name = NULL,   /* we want them in the same directory */
    .attrs = wusbhc_attrs,
};

/*
 * Create a wusbhc instance
 *
 * NOTEs:
 *
 *  - assumes *wusbhc has been zeroed and wusbhc->usb_hcd has been
 *    initialized but not added.
 *
 *  - fill out ports_max, mmcies_max and mmcie_{add,rm} before calling.
 *
 *  - fill out wusbhc->uwb_rc and refcount it before calling
 *  - fill out the wusbhc->sec_modes array
 */
int wusbhc_create(struct wusbhc *wusbhc)
{
    int result = 0;

    wusbhc->trust_timeout = WUSB_TRUST_TIMEOUT_MS;
    wusbhc->phy_rate = UWB_PHY_RATE_INVALID - 1;

    mutex_init(&wusbhc->mutex);
    result = wusbhc_mmcie_create(wusbhc);
    if (result < 0)
        goto error_mmcie_create;
    result = wusbhc_devconnect_create(wusbhc);
    if (result < 0)
        goto error_devconnect_create;
    result = wusbhc_rh_create(wusbhc);
    if (result < 0)
        goto error_rh_create;
    result = wusbhc_sec_create(wusbhc);
    if (result < 0)
        goto error_sec_create;
    return 0;

error_sec_create:
    wusbhc_rh_destroy(wusbhc);
error_rh_create:
    wusbhc_devconnect_destroy(wusbhc);
error_devconnect_create:
    wusbhc_mmcie_destroy(wusbhc);
error_mmcie_create:
    return result;
}
EXPORT_SYMBOL_GPL(wusbhc_create);

static inline struct kobject *wusbhc_kobj(struct wusbhc *wusbhc)
{
    return &wusbhc->usb_hcd.self.controller->kobj;
}

/*
 * Phase B of a wusbhc instance creation
 *
 * Creates fields that depend on wusbhc->usb_hcd having been
 * added. This is where we create the sysfs files in
 * /sys/class/usb_host/usb_hostX/.
 *
 * NOTE: Assumes wusbhc->usb_hcd has been already added by the upper
 *       layer (hwahc or whci)
 */
int wusbhc_b_create(struct wusbhc *wusbhc)
{
    int result = 0;
    struct device *dev = wusbhc->usb_hcd.self.controller;

    result = sysfs_create_group(wusbhc_kobj(wusbhc), &wusbhc_attr_group);
    if (result < 0) {
        dev_err(dev, "Cannot register WUSBHC attributes: %d\n", result);
        goto error_create_attr_group;
    }

    result = wusbhc_pal_register(wusbhc);
    if (result < 0)
        goto error_pal_register;
    return 0;

error_pal_register:
    sysfs_remove_group(wusbhc_kobj(wusbhc), &wusbhc_attr_group);
error_create_attr_group:
    return result;
}
EXPORT_SYMBOL_GPL(wusbhc_b_create);

void wusbhc_b_destroy(struct wusbhc *wusbhc)
{
    wusbhc_pal_unregister(wusbhc);
    sysfs_remove_group(wusbhc_kobj(wusbhc), &wusbhc_attr_group);
}
EXPORT_SYMBOL_GPL(wusbhc_b_destroy);

void wusbhc_destroy(struct wusbhc *wusbhc)
{
    wusbhc_sec_destroy(wusbhc);
    wusbhc_rh_destroy(wusbhc);
    wusbhc_devconnect_destroy(wusbhc);
    wusbhc_mmcie_destroy(wusbhc);
}
EXPORT_SYMBOL_GPL(wusbhc_destroy);

struct workqueue_struct *wusbd;
EXPORT_SYMBOL_GPL(wusbd);

/*
 * WUSB Cluster ID allocation map
 *
 * Each WUSB bus in a channel is identified with a Cluster Id in the
 * unauth address pace (WUSB1.0[4.3]). We take the range 0xe0 to 0xff
 * (that's space for 31 WUSB controllers, as 0xff can't be taken). We
 * start taking from 0xff, 0xfe, 0xfd... (hence the += or -= 0xff).
 *
 * For each one we taken, we pin it in the bitap
 */
#define CLUSTER_IDS 32
static DECLARE_BITMAP(wusb_cluster_id_table, CLUSTER_IDS);
static DEFINE_SPINLOCK(wusb_cluster_ids_lock);

/*
 * Get a WUSB Cluster ID
 *
 * Need to release with wusb_cluster_id_put() when done w/ it.
 */
/* FIXME: coordinate with the choose_addres() from the USB stack */
/* we want to leave the top of the 128 range for cluster addresses and
 * the bottom for device addresses (as we map them one on one with
 * ports). */
u8 wusb_cluster_id_get(void)
{
    u8 id;
    spin_lock(&wusb_cluster_ids_lock);
    id = find_first_zero_bit(wusb_cluster_id_table, CLUSTER_IDS);
    if (id >= CLUSTER_IDS) {
        id = 0;
        goto out;
    }
    set_bit(id, wusb_cluster_id_table);
    id = (u8) 0xff - id;
out:
    spin_unlock(&wusb_cluster_ids_lock);
    return id;

}
EXPORT_SYMBOL_GPL(wusb_cluster_id_get);

/*
 * Release a WUSB Cluster ID
 *
 * Obtained it with wusb_cluster_id_get()
 */
void wusb_cluster_id_put(u8 id)
{
    id = 0xff - id;
    BUG_ON(id >= CLUSTER_IDS);
    spin_lock(&wusb_cluster_ids_lock);
    WARN_ON(!test_bit(id, wusb_cluster_id_table));
    clear_bit(id, wusb_cluster_id_table);
    spin_unlock(&wusb_cluster_ids_lock);
}
EXPORT_SYMBOL_GPL(wusb_cluster_id_put);

void wusbhc_giveback_urb(struct wusbhc *wusbhc, struct urb *urb, int status)
{
    struct wusb_dev *wusb_dev = __wusb_dev_get_by_usb_dev(wusbhc, urb->dev);

    if (status == 0 && wusb_dev) {
        wusb_dev->entry_ts = jiffies;

        /* wusbhc_devconnect_acked() can't be called from
           atomic context so defer it to a work queue. */
        if (!list_empty(&wusb_dev->cack_node))
            queue_work(wusbd, &wusb_dev->devconnect_acked_work);
        else
            wusb_dev_put(wusb_dev);
    }

    usb_hcd_giveback_urb(&wusbhc->usb_hcd, urb, status);
}
EXPORT_SYMBOL_GPL(wusbhc_giveback_urb);

void wusbhc_reset_all(struct wusbhc *wusbhc)
{
    uwb_rc_reset_all(wusbhc->uwb_rc);
}
EXPORT_SYMBOL_GPL(wusbhc_reset_all);

static struct notifier_block wusb_usb_notifier = {
    .notifier_call = wusb_usb_ncb,
    .priority = INT_MAX /* Need to be called first of all */
};

static int __init wusbcore_init(void)
{
    int result;
    result = wusb_crypto_init();
    if (result < 0)
        goto error_crypto_init;
    /* WQ is singlethread because we need to serialize notifications */
    wusbd = create_singlethread_workqueue("wusbd");
    if (wusbd == NULL) {
        result = -ENOMEM;
        printk(KERN_ERR "WUSB-core: Cannot create wusbd workqueue\n");
        goto error_wusbd_create;
    }
    usb_register_notify(&wusb_usb_notifier);
    bitmap_zero(wusb_cluster_id_table, CLUSTER_IDS);
    set_bit(0, wusb_cluster_id_table);  /* reserve Cluster ID 0xff */
    return 0;

error_wusbd_create:
    wusb_crypto_exit();
error_crypto_init:
    return result;

}
module_init(wusbcore_init);

static void __exit wusbcore_exit(void)
{
    clear_bit(0, wusb_cluster_id_table);
    if (!bitmap_empty(wusb_cluster_id_table, CLUSTER_IDS)) {
        char buf[256];
        bitmap_scnprintf(buf, sizeof(buf), wusb_cluster_id_table,
                 CLUSTER_IDS);
        printk(KERN_ERR "BUG: WUSB Cluster IDs not released "
               "on exit: %s\n", buf);
        WARN_ON(1);
    }
    usb_unregister_notify(&wusb_usb_notifier);
    destroy_workqueue(wusbd);
    wusb_crypto_exit();
}
module_exit(wusbcore_exit);

MODULE_AUTHOR("Inaky Perez-Gonzalez <[email protected]>");
MODULE_DESCRIPTION("Wireless USB core");
MODULE_LICENSE("GPL");