diff options
Diffstat (limited to 'kernel/drivers/usb/wusbcore/devconnect.c')
| -rw-r--r-- | kernel/drivers/usb/wusbcore/devconnect.c | 1100 |
1 files changed, 1100 insertions, 0 deletions
diff --git a/kernel/drivers/usb/wusbcore/devconnect.c b/kernel/drivers/usb/wusbcore/devconnect.c new file mode 100644 index 000000000..3f4f5fbde --- /dev/null +++ b/kernel/drivers/usb/wusbcore/devconnect.c @@ -0,0 +1,1100 @@ +/* + * WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8]) + * Device Connect handling + * + * Copyright (C) 2006 Intel Corporation + * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> + * + * 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. + * + * + * FIXME: docs + * FIXME: this file needs to be broken up, it's grown too big + * + * + * WUSB1.0[7.1, 7.5.1, ] + * + * WUSB device connection is kind of messy. Some background: + * + * When a device wants to connect it scans the UWB radio channels + * looking for a WUSB Channel; a WUSB channel is defined by MMCs + * (Micro Managed Commands or something like that) [see + * Design-overview for more on this] . + * + * So, device scans the radio, finds MMCs and thus a host and checks + * when the next DNTS is. It sends a Device Notification Connect + * (DN_Connect); the host picks it up (through nep.c and notif.c, ends + * up in wusb_devconnect_ack(), which creates a wusb_dev structure in + * wusbhc->port[port_number].wusb_dev), assigns an unauth address + * to the device (this means from 0x80 to 0xfe) and sends, in the MMC + * a Connect Ack Information Element (ConnAck IE). + * + * So now the device now has a WUSB address. From now on, we use + * that to talk to it in the RPipes. + * + * ASSUMPTIONS: + * + * - We use the the as device address the port number where it is + * connected (port 0 doesn't exist). For unauth, it is 128 + that. + * + * ROADMAP: + * + * This file contains the logic for doing that--entry points: + * + * wusb_devconnect_ack() Ack a device until _acked() called. + * Called by notif.c:wusb_handle_dn_connect() + * when a DN_Connect is received. + * + * wusb_devconnect_acked() Ack done, release resources. + * + * wusb_handle_dn_alive() Called by notif.c:wusb_handle_dn() + * for processing a DN_Alive pong from a device. + * + * wusb_handle_dn_disconnect()Called by notif.c:wusb_handle_dn() to + * process a disconenct request from a + * device. + * + * __wusb_dev_disable() Called by rh.c:wusbhc_rh_clear_port_feat() when + * disabling a port. + * + * wusb_devconnect_create() Called when creating the host by + * lc.c:wusbhc_create(). + * + * wusb_devconnect_destroy() Cleanup called removing the host. Called + * by lc.c:wusbhc_destroy(). + * + * Each Wireless USB host maintains a list of DN_Connect requests + * (actually we maintain a list of pending Connect Acks, the + * wusbhc->ca_list). + * + * LIFE CYCLE OF port->wusb_dev + * + * Before the @wusbhc structure put()s the reference it owns for + * port->wusb_dev [and clean the wusb_dev pointer], it needs to + * lock @wusbhc->mutex. + */ + +#include <linux/jiffies.h> +#include <linux/ctype.h> +#include <linux/slab.h> +#include <linux/workqueue.h> +#include <linux/export.h> +#include "wusbhc.h" + +static void wusbhc_devconnect_acked_work(struct work_struct *work); + +static void wusb_dev_free(struct wusb_dev *wusb_dev) +{ + kfree(wusb_dev); +} + +static struct wusb_dev *wusb_dev_alloc(struct wusbhc *wusbhc) +{ + struct wusb_dev *wusb_dev; + + wusb_dev = kzalloc(sizeof(*wusb_dev), GFP_KERNEL); + if (wusb_dev == NULL) + goto err; + + wusb_dev->wusbhc = wusbhc; + + INIT_WORK(&wusb_dev->devconnect_acked_work, wusbhc_devconnect_acked_work); + + return wusb_dev; +err: + wusb_dev_free(wusb_dev); + return NULL; +} + + +/* + * Using the Connect-Ack list, fill out the @wusbhc Connect-Ack WUSB IE + * properly so that it can be added to the MMC. + * + * We just get the @wusbhc->ca_list and fill out the first four ones or + * less (per-spec WUSB1.0[7.5, before T7-38). If the ConnectAck WUSB + * IE is not allocated, we alloc it. + * + * @wusbhc->mutex must be taken + */ +static void wusbhc_fill_cack_ie(struct wusbhc *wusbhc) +{ + unsigned cnt; + struct wusb_dev *dev_itr; + struct wuie_connect_ack *cack_ie; + + cack_ie = &wusbhc->cack_ie; + cnt = 0; + list_for_each_entry(dev_itr, &wusbhc->cack_list, cack_node) { + cack_ie->blk[cnt].CDID = dev_itr->cdid; + cack_ie->blk[cnt].bDeviceAddress = dev_itr->addr; + if (++cnt >= WUIE_ELT_MAX) + break; + } + cack_ie->hdr.bLength = sizeof(cack_ie->hdr) + + cnt * sizeof(cack_ie->blk[0]); +} + +/* + * Register a new device that wants to connect + * + * A new device wants to connect, so we add it to the Connect-Ack + * list. We give it an address in the unauthorized range (bit 8 set); + * user space will have to drive authorization further on. + * + * @dev_addr: address to use for the device (which is also the port + * number). + * + * @wusbhc->mutex must be taken + */ +static struct wusb_dev *wusbhc_cack_add(struct wusbhc *wusbhc, + struct wusb_dn_connect *dnc, + const char *pr_cdid, u8 port_idx) +{ + struct device *dev = wusbhc->dev; + struct wusb_dev *wusb_dev; + int new_connection = wusb_dn_connect_new_connection(dnc); + u8 dev_addr; + int result; + + /* Is it registered already? */ + list_for_each_entry(wusb_dev, &wusbhc->cack_list, cack_node) + if (!memcmp(&wusb_dev->cdid, &dnc->CDID, + sizeof(wusb_dev->cdid))) + return wusb_dev; + /* We don't have it, create an entry, register it */ + wusb_dev = wusb_dev_alloc(wusbhc); + if (wusb_dev == NULL) + return NULL; + wusb_dev_init(wusb_dev); + wusb_dev->cdid = dnc->CDID; + wusb_dev->port_idx = port_idx; + + /* + * Devices are always available within the cluster reservation + * and since the hardware will take the intersection of the + * per-device availability and the cluster reservation, the + * per-device availability can simply be set to always + * available. + */ + bitmap_fill(wusb_dev->availability.bm, UWB_NUM_MAS); + + /* FIXME: handle reconnects instead of assuming connects are + always new. */ + if (1 && new_connection == 0) + new_connection = 1; + if (new_connection) { + dev_addr = (port_idx + 2) | WUSB_DEV_ADDR_UNAUTH; + + dev_info(dev, "Connecting new WUSB device to address %u, " + "port %u\n", dev_addr, port_idx); + + result = wusb_set_dev_addr(wusbhc, wusb_dev, dev_addr); + if (result < 0) + return NULL; + } + wusb_dev->entry_ts = jiffies; + list_add_tail(&wusb_dev->cack_node, &wusbhc->cack_list); + wusbhc->cack_count++; + wusbhc_fill_cack_ie(wusbhc); + + return wusb_dev; +} + +/* + * Remove a Connect-Ack context entry from the HCs view + * + * @wusbhc->mutex must be taken + */ +static void wusbhc_cack_rm(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev) +{ + list_del_init(&wusb_dev->cack_node); + wusbhc->cack_count--; + wusbhc_fill_cack_ie(wusbhc); +} + +/* + * @wusbhc->mutex must be taken */ +static +void wusbhc_devconnect_acked(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev) +{ + wusbhc_cack_rm(wusbhc, wusb_dev); + if (wusbhc->cack_count) + wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->cack_ie.hdr); + else + wusbhc_mmcie_rm(wusbhc, &wusbhc->cack_ie.hdr); +} + +static void wusbhc_devconnect_acked_work(struct work_struct *work) +{ + struct wusb_dev *wusb_dev = container_of(work, struct wusb_dev, + devconnect_acked_work); + struct wusbhc *wusbhc = wusb_dev->wusbhc; + + mutex_lock(&wusbhc->mutex); + wusbhc_devconnect_acked(wusbhc, wusb_dev); + mutex_unlock(&wusbhc->mutex); + + wusb_dev_put(wusb_dev); +} + +/* + * Ack a device for connection + * + * FIXME: docs + * + * @pr_cdid: Printable CDID...hex Use @dnc->cdid for the real deal. + * + * So we get the connect ack IE (may have been allocated already), + * find an empty connect block, an empty virtual port, create an + * address with it (see below), make it an unauth addr [bit 7 set] and + * set the MMC. + * + * Addresses: because WUSB hosts have no downstream hubs, we can do a + * 1:1 mapping between 'port number' and device + * address. This simplifies many things, as during this + * initial connect phase the USB stack has no knowledge of + * the device and hasn't assigned an address yet--we know + * USB's choose_address() will use the same heuristics we + * use here, so we can assume which address will be assigned. + * + * USB stack always assigns address 1 to the root hub, so + * to the port number we add 2 (thus virtual port #0 is + * addr #2). + * + * @wusbhc shall be referenced + */ +static +void wusbhc_devconnect_ack(struct wusbhc *wusbhc, struct wusb_dn_connect *dnc, + const char *pr_cdid) +{ + int result; + struct device *dev = wusbhc->dev; + struct wusb_dev *wusb_dev; + struct wusb_port *port; + unsigned idx; + + mutex_lock(&wusbhc->mutex); + + /* Check we are not handling it already */ + for (idx = 0; idx < wusbhc->ports_max; idx++) { + port = wusb_port_by_idx(wusbhc, idx); + if (port->wusb_dev + && memcmp(&dnc->CDID, &port->wusb_dev->cdid, sizeof(dnc->CDID)) == 0) + goto error_unlock; + } + /* Look up those fake ports we have for a free one */ + for (idx = 0; idx < wusbhc->ports_max; idx++) { + port = wusb_port_by_idx(wusbhc, idx); + if ((port->status & USB_PORT_STAT_POWER) + && !(port->status & USB_PORT_STAT_CONNECTION)) + break; + } + if (idx >= wusbhc->ports_max) { + dev_err(dev, "Host controller can't connect more devices " + "(%u already connected); device %s rejected\n", + wusbhc->ports_max, pr_cdid); + /* NOTE: we could send a WUIE_Disconnect here, but we haven't + * event acked, so the device will eventually timeout the + * connection, right? */ + goto error_unlock; + } + + /* Make sure we are using no crypto on that "virtual port" */ + wusbhc->set_ptk(wusbhc, idx, 0, NULL, 0); + + /* Grab a filled in Connect-Ack context, fill out the + * Connect-Ack Wireless USB IE, set the MMC */ + wusb_dev = wusbhc_cack_add(wusbhc, dnc, pr_cdid, idx); + if (wusb_dev == NULL) + goto error_unlock; + result = wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->cack_ie.hdr); + if (result < 0) + goto error_unlock; + /* Give the device at least 2ms (WUSB1.0[7.5.1p3]), let's do + * three for a good measure */ + msleep(3); + port->wusb_dev = wusb_dev; + port->status |= USB_PORT_STAT_CONNECTION; + port->change |= USB_PORT_STAT_C_CONNECTION; + /* Now the port status changed to connected; hub_wq will + * pick the change up and try to reset the port to bring it to + * the enabled state--so this process returns up to the stack + * and it calls back into wusbhc_rh_port_reset(). + */ +error_unlock: + mutex_unlock(&wusbhc->mutex); + return; + +} + +/* + * Disconnect a Wireless USB device from its fake port + * + * Marks the port as disconnected so that hub_wq can pick up the change + * and drops our knowledge about the device. + * + * Assumes there is a device connected + * + * @port_index: zero based port number + * + * NOTE: @wusbhc->mutex is locked + * + * WARNING: From here it is not very safe to access anything hanging off + * wusb_dev + */ +static void __wusbhc_dev_disconnect(struct wusbhc *wusbhc, + struct wusb_port *port) +{ + struct wusb_dev *wusb_dev = port->wusb_dev; + + port->status &= ~(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE + | USB_PORT_STAT_SUSPEND | USB_PORT_STAT_RESET + | USB_PORT_STAT_LOW_SPEED | USB_PORT_STAT_HIGH_SPEED); + port->change |= USB_PORT_STAT_C_CONNECTION | USB_PORT_STAT_C_ENABLE; + if (wusb_dev) { + dev_dbg(wusbhc->dev, "disconnecting device from port %d\n", wusb_dev->port_idx); + if (!list_empty(&wusb_dev->cack_node)) + list_del_init(&wusb_dev->cack_node); + /* For the one in cack_add() */ + wusb_dev_put(wusb_dev); + } + port->wusb_dev = NULL; + + /* After a device disconnects, change the GTK (see [WUSB] + * section 6.2.11.2). */ + if (wusbhc->active) + wusbhc_gtk_rekey(wusbhc); + + /* The Wireless USB part has forgotten about the device already; now + * hub_wq's timer will pick up the disconnection and remove the USB + * device from the system + */ +} + +/* + * Refresh the list of keep alives to emit in the MMC + * + * We only publish the first four devices that have a coming timeout + * condition. Then when we are done processing those, we go for the + * next ones. We ignore the ones that have timed out already (they'll + * be purged). + * + * This might cause the first devices to timeout the last devices in + * the port array...FIXME: come up with a better algorithm? + * + * Note we can't do much about MMC's ops errors; we hope next refresh + * will kind of handle it. + * + * NOTE: @wusbhc->mutex is locked + */ +static void __wusbhc_keep_alive(struct wusbhc *wusbhc) +{ + struct device *dev = wusbhc->dev; + unsigned cnt; + struct wusb_dev *wusb_dev; + struct wusb_port *wusb_port; + struct wuie_keep_alive *ie = &wusbhc->keep_alive_ie; + unsigned keep_alives, old_keep_alives; + + old_keep_alives = ie->hdr.bLength - sizeof(ie->hdr); + keep_alives = 0; + for (cnt = 0; + keep_alives < WUIE_ELT_MAX && cnt < wusbhc->ports_max; + cnt++) { + unsigned tt = msecs_to_jiffies(wusbhc->trust_timeout); + + wusb_port = wusb_port_by_idx(wusbhc, cnt); + wusb_dev = wusb_port->wusb_dev; + + if (wusb_dev == NULL) + continue; + if (wusb_dev->usb_dev == NULL) + continue; + + if (time_after(jiffies, wusb_dev->entry_ts + tt)) { + dev_err(dev, "KEEPALIVE: device %u timed out\n", + wusb_dev->addr); + __wusbhc_dev_disconnect(wusbhc, wusb_port); + } else if (time_after(jiffies, wusb_dev->entry_ts + tt/3)) { + /* Approaching timeout cut off, need to refresh */ + ie->bDeviceAddress[keep_alives++] = wusb_dev->addr; + } + } + if (keep_alives & 0x1) /* pad to even number ([WUSB] section 7.5.9) */ + ie->bDeviceAddress[keep_alives++] = 0x7f; + ie->hdr.bLength = sizeof(ie->hdr) + + keep_alives*sizeof(ie->bDeviceAddress[0]); + if (keep_alives > 0) + wusbhc_mmcie_set(wusbhc, 10, 5, &ie->hdr); + else if (old_keep_alives != 0) + wusbhc_mmcie_rm(wusbhc, &ie->hdr); +} + +/* + * Do a run through all devices checking for timeouts + */ +static void wusbhc_keep_alive_run(struct work_struct *ws) +{ + struct delayed_work *dw = to_delayed_work(ws); + struct wusbhc *wusbhc = container_of(dw, struct wusbhc, keep_alive_timer); + + mutex_lock(&wusbhc->mutex); + __wusbhc_keep_alive(wusbhc); + mutex_unlock(&wusbhc->mutex); + + queue_delayed_work(wusbd, &wusbhc->keep_alive_timer, + msecs_to_jiffies(wusbhc->trust_timeout / 2)); +} + +/* + * Find the wusb_dev from its device address. + * + * The device can be found directly from the address (see + * wusb_cack_add() for where the device address is set to port_idx + * +2), except when the address is zero. + */ +static struct wusb_dev *wusbhc_find_dev_by_addr(struct wusbhc *wusbhc, u8 addr) +{ + int p; + + if (addr == 0xff) /* unconnected */ + return NULL; + + if (addr > 0) { + int port = (addr & ~0x80) - 2; + if (port < 0 || port >= wusbhc->ports_max) + return NULL; + return wusb_port_by_idx(wusbhc, port)->wusb_dev; + } + + /* Look for the device with address 0. */ + for (p = 0; p < wusbhc->ports_max; p++) { + struct wusb_dev *wusb_dev = wusb_port_by_idx(wusbhc, p)->wusb_dev; + if (wusb_dev && wusb_dev->addr == addr) + return wusb_dev; + } + return NULL; +} + +/* + * Handle a DN_Alive notification (WUSB1.0[7.6.1]) + * + * This just updates the device activity timestamp and then refreshes + * the keep alive IE. + * + * @wusbhc shall be referenced and unlocked + */ +static void wusbhc_handle_dn_alive(struct wusbhc *wusbhc, u8 srcaddr) +{ + struct wusb_dev *wusb_dev; + + mutex_lock(&wusbhc->mutex); + wusb_dev = wusbhc_find_dev_by_addr(wusbhc, srcaddr); + if (wusb_dev == NULL) { + dev_dbg(wusbhc->dev, "ignoring DN_Alive from unconnected device %02x\n", + srcaddr); + } else { + wusb_dev->entry_ts = jiffies; + __wusbhc_keep_alive(wusbhc); + } + mutex_unlock(&wusbhc->mutex); +} + +/* + * Handle a DN_Connect notification (WUSB1.0[7.6.1]) + * + * @wusbhc + * @pkt_hdr + * @size: Size of the buffer where the notification resides; if the + * notification data suggests there should be more data than + * available, an error will be signaled and the whole buffer + * consumed. + * + * @wusbhc->mutex shall be held + */ +static void wusbhc_handle_dn_connect(struct wusbhc *wusbhc, + struct wusb_dn_hdr *dn_hdr, + size_t size) +{ + struct device *dev = wusbhc->dev; + struct wusb_dn_connect *dnc; + char pr_cdid[WUSB_CKHDID_STRSIZE]; + static const char *beacon_behaviour[] = { + "reserved", + "self-beacon", + "directed-beacon", + "no-beacon" + }; + + if (size < sizeof(*dnc)) { + dev_err(dev, "DN CONNECT: short notification (%zu < %zu)\n", + size, sizeof(*dnc)); + return; + } + + dnc = container_of(dn_hdr, struct wusb_dn_connect, hdr); + ckhdid_printf(pr_cdid, sizeof(pr_cdid), &dnc->CDID); + dev_info(dev, "DN CONNECT: device %s @ %x (%s) wants to %s\n", + pr_cdid, + wusb_dn_connect_prev_dev_addr(dnc), + beacon_behaviour[wusb_dn_connect_beacon_behavior(dnc)], + wusb_dn_connect_new_connection(dnc) ? "connect" : "reconnect"); + /* ACK the connect */ + wusbhc_devconnect_ack(wusbhc, dnc, pr_cdid); +} + +/* + * Handle a DN_Disconnect notification (WUSB1.0[7.6.1]) + * + * Device is going down -- do the disconnect. + * + * @wusbhc shall be referenced and unlocked + */ +static void wusbhc_handle_dn_disconnect(struct wusbhc *wusbhc, u8 srcaddr) +{ + struct device *dev = wusbhc->dev; + struct wusb_dev *wusb_dev; + + mutex_lock(&wusbhc->mutex); + wusb_dev = wusbhc_find_dev_by_addr(wusbhc, srcaddr); + if (wusb_dev == NULL) { + dev_dbg(dev, "ignoring DN DISCONNECT from unconnected device %02x\n", + srcaddr); + } else { + dev_info(dev, "DN DISCONNECT: device 0x%02x going down\n", + wusb_dev->addr); + __wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, + wusb_dev->port_idx)); + } + mutex_unlock(&wusbhc->mutex); +} + +/* + * Handle a Device Notification coming a host + * + * The Device Notification comes from a host (HWA, DWA or WHCI) + * wrapped in a set of headers. Somebody else has peeled off those + * headers for us and we just get one Device Notifications. + * + * Invalid DNs (e.g., too short) are discarded. + * + * @wusbhc shall be referenced + * + * FIXMES: + * - implement priorities as in WUSB1.0[Table 7-55]? + */ +void wusbhc_handle_dn(struct wusbhc *wusbhc, u8 srcaddr, + struct wusb_dn_hdr *dn_hdr, size_t size) +{ + struct device *dev = wusbhc->dev; + + if (size < sizeof(struct wusb_dn_hdr)) { + dev_err(dev, "DN data shorter than DN header (%d < %d)\n", + (int)size, (int)sizeof(struct wusb_dn_hdr)); + return; + } + switch (dn_hdr->bType) { + case WUSB_DN_CONNECT: + wusbhc_handle_dn_connect(wusbhc, dn_hdr, size); + break; + case WUSB_DN_ALIVE: + wusbhc_handle_dn_alive(wusbhc, srcaddr); + break; + case WUSB_DN_DISCONNECT: + wusbhc_handle_dn_disconnect(wusbhc, srcaddr); + break; + case WUSB_DN_MASAVAILCHANGED: + case WUSB_DN_RWAKE: + case WUSB_DN_SLEEP: + /* FIXME: handle these DNs. */ + break; + case WUSB_DN_EPRDY: + /* The hardware handles these. */ + break; + default: + dev_warn(dev, "unknown DN %u (%d octets) from %u\n", + dn_hdr->bType, (int)size, srcaddr); + } +} +EXPORT_SYMBOL_GPL(wusbhc_handle_dn); + +/* + * Disconnect a WUSB device from a the cluster + * + * @wusbhc + * @port Fake port where the device is (wusbhc index, not USB port number). + * + * In Wireless USB, a disconnect is basically telling the device he is + * being disconnected and forgetting about him. + * + * We send the device a Device Disconnect IE (WUSB1.0[7.5.11]) for 100 + * ms and then keep going. + * + * We don't do much in case of error; we always pretend we disabled + * the port and disconnected the device. If physically the request + * didn't get there (many things can fail in the way there), the stack + * will reject the device's communication attempts. + * + * @wusbhc should be refcounted and locked + */ +void __wusbhc_dev_disable(struct wusbhc *wusbhc, u8 port_idx) +{ + int result; + struct device *dev = wusbhc->dev; + struct wusb_dev *wusb_dev; + struct wuie_disconnect *ie; + + wusb_dev = wusb_port_by_idx(wusbhc, port_idx)->wusb_dev; + if (wusb_dev == NULL) { + /* reset no device? ignore */ + dev_dbg(dev, "DISCONNECT: no device at port %u, ignoring\n", + port_idx); + return; + } + __wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx)); + + ie = kzalloc(sizeof(*ie), GFP_KERNEL); + if (ie == NULL) + return; + ie->hdr.bLength = sizeof(*ie); + ie->hdr.bIEIdentifier = WUIE_ID_DEVICE_DISCONNECT; + ie->bDeviceAddress = wusb_dev->addr; + result = wusbhc_mmcie_set(wusbhc, 0, 0, &ie->hdr); + if (result < 0) + dev_err(dev, "DISCONNECT: can't set MMC: %d\n", result); + else { + /* At least 6 MMCs, assuming at least 1 MMC per zone. */ + msleep(7*4); + wusbhc_mmcie_rm(wusbhc, &ie->hdr); + } + kfree(ie); +} + +/* + * Walk over the BOS descriptor, verify and grok it + * + * @usb_dev: referenced + * @wusb_dev: referenced and unlocked + * + * The BOS descriptor is defined at WUSB1.0[7.4.1], and it defines a + * "flexible" way to wrap all kinds of descriptors inside an standard + * descriptor (wonder why they didn't use normal descriptors, + * btw). Not like they lack code. + * + * At the end we go to look for the WUSB Device Capabilities + * (WUSB1.0[7.4.1.1]) that is wrapped in a device capability descriptor + * that is part of the BOS descriptor set. That tells us what does the + * device support (dual role, beacon type, UWB PHY rates). + */ +static int wusb_dev_bos_grok(struct usb_device *usb_dev, + struct wusb_dev *wusb_dev, + struct usb_bos_descriptor *bos, size_t desc_size) +{ + ssize_t result; + struct device *dev = &usb_dev->dev; + void *itr, *top; + + /* Walk over BOS capabilities, verify them */ + itr = (void *)bos + sizeof(*bos); + top = itr + desc_size - sizeof(*bos); + while (itr < top) { + struct usb_dev_cap_header *cap_hdr = itr; + size_t cap_size; + u8 cap_type; + if (top - itr < sizeof(*cap_hdr)) { + dev_err(dev, "Device BUG? premature end of BOS header " + "data [offset 0x%02x]: only %zu bytes left\n", + (int)(itr - (void *)bos), top - itr); + result = -ENOSPC; + goto error_bad_cap; + } + cap_size = cap_hdr->bLength; + cap_type = cap_hdr->bDevCapabilityType; + if (cap_size == 0) + break; + if (cap_size > top - itr) { + dev_err(dev, "Device BUG? premature end of BOS data " + "[offset 0x%02x cap %02x %zu bytes]: " + "only %zu bytes left\n", + (int)(itr - (void *)bos), + cap_type, cap_size, top - itr); + result = -EBADF; + goto error_bad_cap; + } + switch (cap_type) { + case USB_CAP_TYPE_WIRELESS_USB: + if (cap_size != sizeof(*wusb_dev->wusb_cap_descr)) + dev_err(dev, "Device BUG? WUSB Capability " + "descriptor is %zu bytes vs %zu " + "needed\n", cap_size, + sizeof(*wusb_dev->wusb_cap_descr)); + else + wusb_dev->wusb_cap_descr = itr; + break; + default: + dev_err(dev, "BUG? Unknown BOS capability 0x%02x " + "(%zu bytes) at offset 0x%02x\n", cap_type, + cap_size, (int)(itr - (void *)bos)); + } + itr += cap_size; + } + result = 0; +error_bad_cap: + return result; +} + +/* + * Add information from the BOS descriptors to the device + * + * @usb_dev: referenced + * @wusb_dev: referenced and unlocked + * + * So what we do is we alloc a space for the BOS descriptor of 64 + * bytes; read the first four bytes which include the wTotalLength + * field (WUSB1.0[T7-26]) and if it fits in those 64 bytes, read the + * whole thing. If not we realloc to that size. + * + * Then we call the groking function, that will fill up + * wusb_dev->wusb_cap_descr, which is what we'll need later on. + */ +static int wusb_dev_bos_add(struct usb_device *usb_dev, + struct wusb_dev *wusb_dev) +{ + ssize_t result; + struct device *dev = &usb_dev->dev; + struct usb_bos_descriptor *bos; + size_t alloc_size = 32, desc_size = 4; + + bos = kmalloc(alloc_size, GFP_KERNEL); + if (bos == NULL) + return -ENOMEM; + result = usb_get_descriptor(usb_dev, USB_DT_BOS, 0, bos, desc_size); + if (result < 4) { + dev_err(dev, "Can't get BOS descriptor or too short: %zd\n", + result); + goto error_get_descriptor; + } + desc_size = le16_to_cpu(bos->wTotalLength); + if (desc_size >= alloc_size) { + kfree(bos); + alloc_size = desc_size; + bos = kmalloc(alloc_size, GFP_KERNEL); + if (bos == NULL) + return -ENOMEM; + } + result = usb_get_descriptor(usb_dev, USB_DT_BOS, 0, bos, desc_size); + if (result < 0 || result != desc_size) { + dev_err(dev, "Can't get BOS descriptor or too short (need " + "%zu bytes): %zd\n", desc_size, result); + goto error_get_descriptor; + } + if (result < sizeof(*bos) + || le16_to_cpu(bos->wTotalLength) != desc_size) { + dev_err(dev, "Can't get BOS descriptor or too short (need " + "%zu bytes): %zd\n", desc_size, result); + goto error_get_descriptor; + } + + result = wusb_dev_bos_grok(usb_dev, wusb_dev, bos, result); + if (result < 0) + goto error_bad_bos; + wusb_dev->bos = bos; + return 0; + +error_bad_bos: +error_get_descriptor: + kfree(bos); + wusb_dev->wusb_cap_descr = NULL; + return result; +} + +static void wusb_dev_bos_rm(struct wusb_dev *wusb_dev) +{ + kfree(wusb_dev->bos); + wusb_dev->wusb_cap_descr = NULL; +}; + +/* + * USB stack's device addition Notifier Callback + * + * Called from drivers/usb/core/hub.c when a new device is added; we + * use this hook to perform certain WUSB specific setup work on the + * new device. As well, it is the first time we can connect the + * wusb_dev and the usb_dev. So we note it down in wusb_dev and take a + * reference that we'll drop. + * + * First we need to determine if the device is a WUSB device (else we + * ignore it). For that we use the speed setting (USB_SPEED_WIRELESS) + * [FIXME: maybe we'd need something more definitive]. If so, we track + * it's usb_busd and from there, the WUSB HC. + * + * Because all WUSB HCs are contained in a 'struct wusbhc', voila, we + * get the wusbhc for the device. + * + * We have a reference on @usb_dev (as we are called at the end of its + * enumeration). + * + * NOTE: @usb_dev locked + */ +static void wusb_dev_add_ncb(struct usb_device *usb_dev) +{ + int result = 0; + struct wusb_dev *wusb_dev; + struct wusbhc *wusbhc; + struct device *dev = &usb_dev->dev; + u8 port_idx; + + if (usb_dev->wusb == 0 || usb_dev->devnum == 1) + return; /* skip non wusb and wusb RHs */ + + usb_set_device_state(usb_dev, USB_STATE_UNAUTHENTICATED); + + wusbhc = wusbhc_get_by_usb_dev(usb_dev); + if (wusbhc == NULL) + goto error_nodev; + mutex_lock(&wusbhc->mutex); + wusb_dev = __wusb_dev_get_by_usb_dev(wusbhc, usb_dev); + port_idx = wusb_port_no_to_idx(usb_dev->portnum); + mutex_unlock(&wusbhc->mutex); + if (wusb_dev == NULL) + goto error_nodev; + wusb_dev->usb_dev = usb_get_dev(usb_dev); + usb_dev->wusb_dev = wusb_dev_get(wusb_dev); + result = wusb_dev_sec_add(wusbhc, usb_dev, wusb_dev); + if (result < 0) { + dev_err(dev, "Cannot enable security: %d\n", result); + goto error_sec_add; + } + /* Now query the device for it's BOS and attach it to wusb_dev */ + result = wusb_dev_bos_add(usb_dev, wusb_dev); + if (result < 0) { + dev_err(dev, "Cannot get BOS descriptors: %d\n", result); + goto error_bos_add; + } + result = wusb_dev_sysfs_add(wusbhc, usb_dev, wusb_dev); + if (result < 0) + goto error_add_sysfs; +out: + wusb_dev_put(wusb_dev); + wusbhc_put(wusbhc); +error_nodev: + return; + + wusb_dev_sysfs_rm(wusb_dev); +error_add_sysfs: + wusb_dev_bos_rm(wusb_dev); +error_bos_add: + wusb_dev_sec_rm(wusb_dev); +error_sec_add: + mutex_lock(&wusbhc->mutex); + __wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx)); + mutex_unlock(&wusbhc->mutex); + goto out; +} + +/* + * Undo all the steps done at connection by the notifier callback + * + * NOTE: @usb_dev locked + */ +static void wusb_dev_rm_ncb(struct usb_device *usb_dev) +{ + struct wusb_dev *wusb_dev = usb_dev->wusb_dev; + + if (usb_dev->wusb == 0 || usb_dev->devnum == 1) + return; /* skip non wusb and wusb RHs */ + + wusb_dev_sysfs_rm(wusb_dev); + wusb_dev_bos_rm(wusb_dev); + wusb_dev_sec_rm(wusb_dev); + wusb_dev->usb_dev = NULL; + usb_dev->wusb_dev = NULL; + wusb_dev_put(wusb_dev); + usb_put_dev(usb_dev); +} + +/* + * Handle notifications from the USB stack (notifier call back) + * + * This is called when the USB stack does a + * usb_{bus,device}_{add,remove}() so we can do WUSB specific + * handling. It is called with [for the case of + * USB_DEVICE_{ADD,REMOVE} with the usb_dev locked. + */ +int wusb_usb_ncb(struct notifier_block *nb, unsigned long val, + void *priv) +{ + int result = NOTIFY_OK; + + switch (val) { + case USB_DEVICE_ADD: + wusb_dev_add_ncb(priv); + break; + case USB_DEVICE_REMOVE: + wusb_dev_rm_ncb(priv); + break; + case USB_BUS_ADD: + /* ignore (for now) */ + case USB_BUS_REMOVE: + break; + default: + WARN_ON(1); + result = NOTIFY_BAD; + } + return result; +} + +/* + * Return a referenced wusb_dev given a @wusbhc and @usb_dev + */ +struct wusb_dev *__wusb_dev_get_by_usb_dev(struct wusbhc *wusbhc, + struct usb_device *usb_dev) +{ + struct wusb_dev *wusb_dev; + u8 port_idx; + + port_idx = wusb_port_no_to_idx(usb_dev->portnum); + BUG_ON(port_idx > wusbhc->ports_max); + wusb_dev = wusb_port_by_idx(wusbhc, port_idx)->wusb_dev; + if (wusb_dev != NULL) /* ops, device is gone */ + wusb_dev_get(wusb_dev); + return wusb_dev; +} +EXPORT_SYMBOL_GPL(__wusb_dev_get_by_usb_dev); + +void wusb_dev_destroy(struct kref *_wusb_dev) +{ + struct wusb_dev *wusb_dev = container_of(_wusb_dev, struct wusb_dev, refcnt); + + list_del_init(&wusb_dev->cack_node); + wusb_dev_free(wusb_dev); +} +EXPORT_SYMBOL_GPL(wusb_dev_destroy); + +/* + * Create all the device connect handling infrastructure + * + * This is basically the device info array, Connect Acknowledgement + * (cack) lists, keep-alive timers (and delayed work thread). + */ +int wusbhc_devconnect_create(struct wusbhc *wusbhc) +{ + wusbhc->keep_alive_ie.hdr.bIEIdentifier = WUIE_ID_KEEP_ALIVE; + wusbhc->keep_alive_ie.hdr.bLength = sizeof(wusbhc->keep_alive_ie.hdr); + INIT_DELAYED_WORK(&wusbhc->keep_alive_timer, wusbhc_keep_alive_run); + + wusbhc->cack_ie.hdr.bIEIdentifier = WUIE_ID_CONNECTACK; + wusbhc->cack_ie.hdr.bLength = sizeof(wusbhc->cack_ie.hdr); + INIT_LIST_HEAD(&wusbhc->cack_list); + + return 0; +} + +/* + * Release all resources taken by the devconnect stuff + */ +void wusbhc_devconnect_destroy(struct wusbhc *wusbhc) +{ + /* no op */ +} + +/* + * wusbhc_devconnect_start - start accepting device connections + * @wusbhc: the WUSB HC + * + * Sets the Host Info IE to accept all new connections. + * + * FIXME: This also enables the keep alives but this is not necessary + * until there are connected and authenticated devices. + */ +int wusbhc_devconnect_start(struct wusbhc *wusbhc) +{ + struct device *dev = wusbhc->dev; + struct wuie_host_info *hi; + int result; + + hi = kzalloc(sizeof(*hi), GFP_KERNEL); + if (hi == NULL) + return -ENOMEM; + + hi->hdr.bLength = sizeof(*hi); + hi->hdr.bIEIdentifier = WUIE_ID_HOST_INFO; + hi->attributes = cpu_to_le16((wusbhc->rsv->stream << 3) | WUIE_HI_CAP_ALL); + hi->CHID = wusbhc->chid; + result = wusbhc_mmcie_set(wusbhc, 0, 0, &hi->hdr); + if (result < 0) { + dev_err(dev, "Cannot add Host Info MMCIE: %d\n", result); + goto error_mmcie_set; + } + wusbhc->wuie_host_info = hi; + + queue_delayed_work(wusbd, &wusbhc->keep_alive_timer, + msecs_to_jiffies(wusbhc->trust_timeout / 2)); + + return 0; + +error_mmcie_set: + kfree(hi); + return result; +} + +/* + * wusbhc_devconnect_stop - stop managing connected devices + * @wusbhc: the WUSB HC + * + * Disconnects any devices still connected, stops the keep alives and + * removes the Host Info IE. + */ +void wusbhc_devconnect_stop(struct wusbhc *wusbhc) +{ + int i; + + mutex_lock(&wusbhc->mutex); + for (i = 0; i < wusbhc->ports_max; i++) { + if (wusbhc->port[i].wusb_dev) + __wusbhc_dev_disconnect(wusbhc, &wusbhc->port[i]); + } + mutex_unlock(&wusbhc->mutex); + + cancel_delayed_work_sync(&wusbhc->keep_alive_timer); + wusbhc_mmcie_rm(wusbhc, &wusbhc->wuie_host_info->hdr); + kfree(wusbhc->wuie_host_info); + wusbhc->wuie_host_info = NULL; +} + +/* + * wusb_set_dev_addr - set the WUSB device address used by the host + * @wusbhc: the WUSB HC the device is connect to + * @wusb_dev: the WUSB device + * @addr: new device address + */ +int wusb_set_dev_addr(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev, u8 addr) +{ + int result; + + wusb_dev->addr = addr; + result = wusbhc->dev_info_set(wusbhc, wusb_dev); + if (result < 0) + dev_err(wusbhc->dev, "device %d: failed to set device " + "address\n", wusb_dev->port_idx); + else + dev_info(wusbhc->dev, "device %d: %s addr %u\n", + wusb_dev->port_idx, + (addr & WUSB_DEV_ADDR_UNAUTH) ? "unauth" : "auth", + wusb_dev->addr); + + return result; +} |