diff options
Diffstat (limited to 'drivers/uwb/est.c')
| -rw-r--r-- | drivers/uwb/est.c | 464 |
1 files changed, 464 insertions, 0 deletions
diff --git a/drivers/uwb/est.c b/drivers/uwb/est.c new file mode 100644 index 000000000..ad30ddfe3 --- /dev/null +++ b/drivers/uwb/est.c @@ -0,0 +1,464 @@ +/* + * Ultra Wide Band Radio Control + * Event Size Tables management + * + * Copyright (C) 2005-2006 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 + * + * Infrastructure, code and data tables for guessing the size of + * events received on the notification endpoints of UWB radio + * controllers. + * + * You define a table of events and for each, its size and how to get + * the extra size. + * + * ENTRY POINTS: + * + * uwb_est_{init/destroy}(): To initialize/release the EST subsystem. + * + * uwb_est_[u]register(): To un/register event size tables + * uwb_est_grow() + * + * uwb_est_find_size(): Get the size of an event + * uwb_est_get_size() + */ +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/export.h> + +#include "uwb-internal.h" + +struct uwb_est { + u16 type_event_high; + u16 vendor, product; + u8 entries; + const struct uwb_est_entry *entry; +}; + +static struct uwb_est *uwb_est; +static u8 uwb_est_size; +static u8 uwb_est_used; +static DEFINE_RWLOCK(uwb_est_lock); + +/** + * WUSB Standard Event Size Table, HWA-RC interface + * + * Sizes for events and notifications type 0 (general), high nibble 0. + */ +static +struct uwb_est_entry uwb_est_00_00xx[] = { + [UWB_RC_EVT_IE_RCV] = { + .size = sizeof(struct uwb_rc_evt_ie_rcv), + .offset = 1 + offsetof(struct uwb_rc_evt_ie_rcv, wIELength), + }, + [UWB_RC_EVT_BEACON] = { + .size = sizeof(struct uwb_rc_evt_beacon), + .offset = 1 + offsetof(struct uwb_rc_evt_beacon, wBeaconInfoLength), + }, + [UWB_RC_EVT_BEACON_SIZE] = { + .size = sizeof(struct uwb_rc_evt_beacon_size), + }, + [UWB_RC_EVT_BPOIE_CHANGE] = { + .size = sizeof(struct uwb_rc_evt_bpoie_change), + .offset = 1 + offsetof(struct uwb_rc_evt_bpoie_change, + wBPOIELength), + }, + [UWB_RC_EVT_BP_SLOT_CHANGE] = { + .size = sizeof(struct uwb_rc_evt_bp_slot_change), + }, + [UWB_RC_EVT_BP_SWITCH_IE_RCV] = { + .size = sizeof(struct uwb_rc_evt_bp_switch_ie_rcv), + .offset = 1 + offsetof(struct uwb_rc_evt_bp_switch_ie_rcv, wIELength), + }, + [UWB_RC_EVT_DEV_ADDR_CONFLICT] = { + .size = sizeof(struct uwb_rc_evt_dev_addr_conflict), + }, + [UWB_RC_EVT_DRP_AVAIL] = { + .size = sizeof(struct uwb_rc_evt_drp_avail) + }, + [UWB_RC_EVT_DRP] = { + .size = sizeof(struct uwb_rc_evt_drp), + .offset = 1 + offsetof(struct uwb_rc_evt_drp, ie_length), + }, + [UWB_RC_EVT_BP_SWITCH_STATUS] = { + .size = sizeof(struct uwb_rc_evt_bp_switch_status), + }, + [UWB_RC_EVT_CMD_FRAME_RCV] = { + .size = sizeof(struct uwb_rc_evt_cmd_frame_rcv), + .offset = 1 + offsetof(struct uwb_rc_evt_cmd_frame_rcv, dataLength), + }, + [UWB_RC_EVT_CHANNEL_CHANGE_IE_RCV] = { + .size = sizeof(struct uwb_rc_evt_channel_change_ie_rcv), + .offset = 1 + offsetof(struct uwb_rc_evt_channel_change_ie_rcv, wIELength), + }, + [UWB_RC_CMD_CHANNEL_CHANGE] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_DEV_ADDR_MGMT] = { + .size = sizeof(struct uwb_rc_evt_dev_addr_mgmt) }, + [UWB_RC_CMD_GET_IE] = { + .size = sizeof(struct uwb_rc_evt_get_ie), + .offset = 1 + offsetof(struct uwb_rc_evt_get_ie, wIELength), + }, + [UWB_RC_CMD_RESET] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_SCAN] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_SET_BEACON_FILTER] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_SET_DRP_IE] = { + .size = sizeof(struct uwb_rc_evt_set_drp_ie), + }, + [UWB_RC_CMD_SET_IE] = { + .size = sizeof(struct uwb_rc_evt_set_ie), + }, + [UWB_RC_CMD_SET_NOTIFICATION_FILTER] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_SET_TX_POWER] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_SLEEP] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_START_BEACON] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_STOP_BEACON] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_BP_MERGE] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_SEND_COMMAND_FRAME] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, + [UWB_RC_CMD_SET_ASIE_NOTIF] = { + .size = sizeof(struct uwb_rc_evt_confirm), + }, +}; + +static +struct uwb_est_entry uwb_est_01_00xx[] = { + [UWB_RC_DAA_ENERGY_DETECTED] = { + .size = sizeof(struct uwb_rc_evt_daa_energy_detected), + }, + [UWB_RC_SET_DAA_ENERGY_MASK] = { + .size = sizeof(struct uwb_rc_evt_set_daa_energy_mask), + }, + [UWB_RC_SET_NOTIFICATION_FILTER_EX] = { + .size = sizeof(struct uwb_rc_evt_set_notification_filter_ex), + }, +}; + +/** + * Initialize the EST subsystem + * + * Register the standard tables also. + * + * FIXME: tag init + */ +int uwb_est_create(void) +{ + int result; + + uwb_est_size = 2; + uwb_est_used = 0; + uwb_est = kcalloc(uwb_est_size, sizeof(uwb_est[0]), GFP_KERNEL); + if (uwb_est == NULL) + return -ENOMEM; + + result = uwb_est_register(UWB_RC_CET_GENERAL, 0, 0xffff, 0xffff, + uwb_est_00_00xx, ARRAY_SIZE(uwb_est_00_00xx)); + if (result < 0) + goto out; + result = uwb_est_register(UWB_RC_CET_EX_TYPE_1, 0, 0xffff, 0xffff, + uwb_est_01_00xx, ARRAY_SIZE(uwb_est_01_00xx)); +out: + return result; +} + + +/** Clean it up */ +void uwb_est_destroy(void) +{ + kfree(uwb_est); + uwb_est = NULL; + uwb_est_size = uwb_est_used = 0; +} + + +/** + * Double the capacity of the EST table + * + * @returns 0 if ok, < 0 errno no error. + */ +static +int uwb_est_grow(void) +{ + size_t actual_size = uwb_est_size * sizeof(uwb_est[0]); + void *new = kmalloc_array(2, actual_size, GFP_ATOMIC); + if (new == NULL) + return -ENOMEM; + memcpy(new, uwb_est, actual_size); + memset(new + actual_size, 0, actual_size); + kfree(uwb_est); + uwb_est = new; + uwb_est_size *= 2; + return 0; +} + + +/** + * Register an event size table + * + * Makes room for it if the table is full, and then inserts it in the + * right position (entries are sorted by type, event_high, vendor and + * then product). + * + * @vendor: vendor code for matching against the device (0x0000 and + * 0xffff mean any); use 0x0000 to force all to match without + * checking possible vendor specific ones, 0xfffff to match + * after checking vendor specific ones. + * + * @product: product code from that vendor; same matching rules, use + * 0x0000 for not allowing vendor specific matches, 0xffff + * for allowing. + * + * This arragement just makes the tables sort differenty. Because the + * table is sorted by growing type-event_high-vendor-product, a zero + * vendor will match before than a 0x456a vendor, that will match + * before a 0xfffff vendor. + * + * @returns 0 if ok, < 0 errno on error (-ENOENT if not found). + */ +/* FIXME: add bus type to vendor/product code */ +int uwb_est_register(u8 type, u8 event_high, u16 vendor, u16 product, + const struct uwb_est_entry *entry, size_t entries) +{ + unsigned long flags; + unsigned itr; + int result = 0; + + write_lock_irqsave(&uwb_est_lock, flags); + if (uwb_est_used == uwb_est_size) { + result = uwb_est_grow(); + if (result < 0) + goto out; + } + /* Find the right spot to insert it in */ + for (itr = 0; itr < uwb_est_used; itr++) + if (uwb_est[itr].type_event_high < type + && uwb_est[itr].vendor < vendor + && uwb_est[itr].product < product) + break; + + /* Shift others to make room for the new one? */ + if (itr < uwb_est_used) + memmove(&uwb_est[itr+1], &uwb_est[itr], uwb_est_used - itr); + uwb_est[itr].type_event_high = type << 8 | event_high; + uwb_est[itr].vendor = vendor; + uwb_est[itr].product = product; + uwb_est[itr].entry = entry; + uwb_est[itr].entries = entries; + uwb_est_used++; +out: + write_unlock_irqrestore(&uwb_est_lock, flags); + return result; +} +EXPORT_SYMBOL_GPL(uwb_est_register); + + +/** + * Unregister an event size table + * + * This just removes the specified entry and moves the ones after it + * to fill in the gap. This is needed to keep the list sorted; no + * reallocation is done to reduce the size of the table. + * + * We unregister by all the data we used to register instead of by + * pointer to the @entry array because we might have used the same + * table for a bunch of IDs (for example). + * + * @returns 0 if ok, < 0 errno on error (-ENOENT if not found). + */ +int uwb_est_unregister(u8 type, u8 event_high, u16 vendor, u16 product, + const struct uwb_est_entry *entry, size_t entries) +{ + unsigned long flags; + unsigned itr; + struct uwb_est est_cmp = { + .type_event_high = type << 8 | event_high, + .vendor = vendor, + .product = product, + .entry = entry, + .entries = entries + }; + write_lock_irqsave(&uwb_est_lock, flags); + for (itr = 0; itr < uwb_est_used; itr++) + if (!memcmp(&uwb_est[itr], &est_cmp, sizeof(est_cmp))) + goto found; + write_unlock_irqrestore(&uwb_est_lock, flags); + return -ENOENT; + +found: + if (itr < uwb_est_used - 1) /* Not last one? move ones above */ + memmove(&uwb_est[itr], &uwb_est[itr+1], uwb_est_used - itr - 1); + uwb_est_used--; + write_unlock_irqrestore(&uwb_est_lock, flags); + return 0; +} +EXPORT_SYMBOL_GPL(uwb_est_unregister); + + +/** + * Get the size of an event from a table + * + * @rceb: pointer to the buffer with the event + * @rceb_size: size of the area pointed to by @rceb in bytes. + * @returns: > 0 Size of the event + * -ENOSPC An area big enough was not provided to look + * ahead into the event's guts and guess the size. + * -EINVAL Unknown event code (wEvent). + * + * This will look at the received RCEB and guess what is the total + * size. For variable sized events, it will look further ahead into + * their length field to see how much data should be read. + * + * Note this size is *not* final--the neh (Notification/Event Handle) + * might specificy an extra size to add. + */ +static +ssize_t uwb_est_get_size(struct uwb_rc *uwb_rc, struct uwb_est *est, + u8 event_low, const struct uwb_rceb *rceb, + size_t rceb_size) +{ + unsigned offset; + ssize_t size; + struct device *dev = &uwb_rc->uwb_dev.dev; + const struct uwb_est_entry *entry; + + size = -ENOENT; + if (event_low >= est->entries) { /* in range? */ + dev_err(dev, "EST %p 0x%04x/%04x/%04x[%u]: event %u out of range\n", + est, est->type_event_high, est->vendor, est->product, + est->entries, event_low); + goto out; + } + size = -ENOENT; + entry = &est->entry[event_low]; + if (entry->size == 0 && entry->offset == 0) { /* unknown? */ + dev_err(dev, "EST %p 0x%04x/%04x/%04x[%u]: event %u unknown\n", + est, est->type_event_high, est->vendor, est->product, + est->entries, event_low); + goto out; + } + offset = entry->offset; /* extra fries with that? */ + if (offset == 0) + size = entry->size; + else { + /* Ops, got an extra size field at 'offset'--read it */ + const void *ptr = rceb; + size_t type_size = 0; + offset--; + size = -ENOSPC; /* enough data for more? */ + switch (entry->type) { + case UWB_EST_16: type_size = sizeof(__le16); break; + case UWB_EST_8: type_size = sizeof(u8); break; + default: BUG(); + } + if (offset + type_size > rceb_size) { + dev_err(dev, "EST %p 0x%04x/%04x/%04x[%u]: " + "not enough data to read extra size\n", + est, est->type_event_high, est->vendor, + est->product, est->entries); + goto out; + } + size = entry->size; + ptr += offset; + switch (entry->type) { + case UWB_EST_16: size += le16_to_cpu(*(__le16 *)ptr); break; + case UWB_EST_8: size += *(u8 *)ptr; break; + default: BUG(); + } + } +out: + return size; +} + + +/** + * Guesses the size of a WA event + * + * @rceb: pointer to the buffer with the event + * @rceb_size: size of the area pointed to by @rceb in bytes. + * @returns: > 0 Size of the event + * -ENOSPC An area big enough was not provided to look + * ahead into the event's guts and guess the size. + * -EINVAL Unknown event code (wEvent). + * + * This will look at the received RCEB and guess what is the total + * size by checking all the tables registered with + * uwb_est_register(). For variable sized events, it will look further + * ahead into their length field to see how much data should be read. + * + * Note this size is *not* final--the neh (Notification/Event Handle) + * might specificy an extra size to add or replace. + */ +ssize_t uwb_est_find_size(struct uwb_rc *rc, const struct uwb_rceb *rceb, + size_t rceb_size) +{ + /* FIXME: add vendor/product data */ + ssize_t size; + struct device *dev = &rc->uwb_dev.dev; + unsigned long flags; + unsigned itr; + u16 type_event_high, event; + + read_lock_irqsave(&uwb_est_lock, flags); + size = -ENOSPC; + if (rceb_size < sizeof(*rceb)) + goto out; + event = le16_to_cpu(rceb->wEvent); + type_event_high = rceb->bEventType << 8 | (event & 0xff00) >> 8; + for (itr = 0; itr < uwb_est_used; itr++) { + if (uwb_est[itr].type_event_high != type_event_high) + continue; + size = uwb_est_get_size(rc, &uwb_est[itr], + event & 0x00ff, rceb, rceb_size); + /* try more tables that might handle the same type */ + if (size != -ENOENT) + goto out; + } + dev_dbg(dev, + "event 0x%02x/%04x/%02x: no handlers available; RCEB %4ph\n", + (unsigned) rceb->bEventType, + (unsigned) le16_to_cpu(rceb->wEvent), + (unsigned) rceb->bEventContext, + rceb); + size = -ENOENT; +out: + read_unlock_irqrestore(&uwb_est_lock, flags); + return size; +} +EXPORT_SYMBOL_GPL(uwb_est_find_size); |