- 根目录:
- drivers
- uwb
- est.c
/*
* 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 "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 = kzalloc(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(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;
u16 type_event_high;
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 */
type_event_high = type << 8 | event_high;
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;
u8 *ptr = (u8 *) rceb;
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 %02x %02x %02x %02x\n",
(unsigned) rceb->bEventType,
(unsigned) le16_to_cpu(rceb->wEvent),
(unsigned) rceb->bEventContext,
ptr[0], ptr[1], ptr[2], ptr[3]);
size = -ENOENT;
out:
read_unlock_irqrestore(&uwb_est_lock, flags);
return size;
}
EXPORT_SYMBOL_GPL(uwb_est_find_size);