- 根目录:
- net
- irda
- ircomm
- ircomm_lmp.c
/*********************************************************************
*
* Filename: ircomm_lmp.c
* Version: 1.0
* Description: Interface between IrCOMM and IrLMP
* Status: Stable
* Author: Dag Brattli <dagb@cs.uit.no>
* Created at: Sun Jun 6 20:48:27 1999
* Modified at: Sun Dec 12 13:44:17 1999
* Modified by: Dag Brattli <dagb@cs.uit.no>
* Sources: Previous IrLPT work by Thomas Davis
*
* Copyright (c) 1999 Dag Brattli, All Rights Reserved.
* Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* 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, see <http://www.gnu.org/licenses/>.
*
********************************************************************/
#include <linux/init.h>
#include <linux/gfp.h>
#include <net/irda/irda.h>
#include <net/irda/irlmp.h>
#include <net/irda/iriap.h>
#include <net/irda/irda_device.h> /* struct irda_skb_cb */
#include <net/irda/ircomm_event.h>
#include <net/irda/ircomm_lmp.h>
/*
* Function ircomm_lmp_connect_request (self, userdata)
*
*
*
*/
static int ircomm_lmp_connect_request(struct ircomm_cb *self,
struct sk_buff *userdata,
struct ircomm_info *info)
{
int ret = 0;
/* Don't forget to refcount it - should be NULL anyway */
if(userdata)
skb_get(userdata);
ret = irlmp_connect_request(self->lsap, info->dlsap_sel,
info->saddr, info->daddr, NULL, userdata);
return ret;
}
/*
* Function ircomm_lmp_connect_response (self, skb)
*
*
*
*/
static int ircomm_lmp_connect_response(struct ircomm_cb *self,
struct sk_buff *userdata)
{
struct sk_buff *tx_skb;
/* Any userdata supplied? */
if (userdata == NULL) {
tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
if (!tx_skb)
return -ENOMEM;
/* Reserve space for MUX and LAP header */
skb_reserve(tx_skb, LMP_MAX_HEADER);
} else {
/*
* Check that the client has reserved enough space for
* headers
*/
IRDA_ASSERT(skb_headroom(userdata) >= LMP_MAX_HEADER,
return -1;);
/* Don't forget to refcount it - should be NULL anyway */
skb_get(userdata);
tx_skb = userdata;
}
return irlmp_connect_response(self->lsap, tx_skb);
}
static int ircomm_lmp_disconnect_request(struct ircomm_cb *self,
struct sk_buff *userdata,
struct ircomm_info *info)
{
struct sk_buff *tx_skb;
int ret;
if (!userdata) {
tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
if (!tx_skb)
return -ENOMEM;
/* Reserve space for MUX and LAP header */
skb_reserve(tx_skb, LMP_MAX_HEADER);
userdata = tx_skb;
} else {
/* Don't forget to refcount it - should be NULL anyway */
skb_get(userdata);
}
ret = irlmp_disconnect_request(self->lsap, userdata);
return ret;
}
/*
* Function ircomm_lmp_flow_control (skb)
*
* This function is called when a data frame we have sent to IrLAP has
* been deallocated. We do this to make sure we don't flood IrLAP with
* frames, since we are not using the IrTTP flow control mechanism
*/
static void ircomm_lmp_flow_control(struct sk_buff *skb)
{
struct irda_skb_cb *cb;
struct ircomm_cb *self;
int line;
IRDA_ASSERT(skb != NULL, return;);
cb = (struct irda_skb_cb *) skb->cb;
line = cb->line;
self = (struct ircomm_cb *) hashbin_lock_find(ircomm, line, NULL);
if (!self) {
pr_debug("%s(), didn't find myself\n", __func__);
return;
}
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
self->pkt_count--;
if ((self->pkt_count < 2) && (self->flow_status == FLOW_STOP)) {
pr_debug("%s(), asking TTY to start again!\n", __func__);
self->flow_status = FLOW_START;
if (self->notify.flow_indication)
self->notify.flow_indication(self->notify.instance,
self, FLOW_START);
}
}
/*
* Function ircomm_lmp_data_request (self, userdata)
*
* Send data frame to peer device
*
*/
static int ircomm_lmp_data_request(struct ircomm_cb *self,
struct sk_buff *skb,
int not_used)
{
struct irda_skb_cb *cb;
int ret;
IRDA_ASSERT(skb != NULL, return -1;);
cb = (struct irda_skb_cb *) skb->cb;
cb->line = self->line;
pr_debug("%s(), sending frame\n", __func__);
/* Don't forget to refcount it - see ircomm_tty_do_softint() */
skb_get(skb);
skb_orphan(skb);
skb->destructor = ircomm_lmp_flow_control;
if ((self->pkt_count++ > 7) && (self->flow_status == FLOW_START)) {
pr_debug("%s(), asking TTY to slow down!\n", __func__);
self->flow_status = FLOW_STOP;
if (self->notify.flow_indication)
self->notify.flow_indication(self->notify.instance,
self, FLOW_STOP);
}
ret = irlmp_data_request(self->lsap, skb);
if (ret) {
net_err_ratelimited("%s(), failed\n", __func__);
/* irlmp_data_request already free the packet */
}
return ret;
}
/*
* Function ircomm_lmp_data_indication (instance, sap, skb)
*
* Incoming data which we must deliver to the state machine, to check
* we are still connected.
*/
static int ircomm_lmp_data_indication(void *instance, void *sap,
struct sk_buff *skb)
{
struct ircomm_cb *self = (struct ircomm_cb *) instance;
IRDA_ASSERT(self != NULL, return -1;);
IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return -1;);
IRDA_ASSERT(skb != NULL, return -1;);
ircomm_do_event(self, IRCOMM_LMP_DATA_INDICATION, skb, NULL);
/* Drop reference count - see ircomm_tty_data_indication(). */
dev_kfree_skb(skb);
return 0;
}
/*
* Function ircomm_lmp_connect_confirm (instance, sap, qos, max_sdu_size,
* max_header_size, skb)
*
* Connection has been confirmed by peer device
*
*/
static void ircomm_lmp_connect_confirm(void *instance, void *sap,
struct qos_info *qos,
__u32 max_seg_size,
__u8 max_header_size,
struct sk_buff *skb)
{
struct ircomm_cb *self = (struct ircomm_cb *) instance;
struct ircomm_info info;
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
IRDA_ASSERT(skb != NULL, return;);
IRDA_ASSERT(qos != NULL, return;);
info.max_data_size = max_seg_size;
info.max_header_size = max_header_size;
info.qos = qos;
ircomm_do_event(self, IRCOMM_LMP_CONNECT_CONFIRM, skb, &info);
/* Drop reference count - see ircomm_tty_connect_confirm(). */
dev_kfree_skb(skb);
}
/*
* Function ircomm_lmp_connect_indication (instance, sap, qos, max_sdu_size,
* max_header_size, skb)
*
* Peer device wants to make a connection with us
*
*/
static void ircomm_lmp_connect_indication(void *instance, void *sap,
struct qos_info *qos,
__u32 max_seg_size,
__u8 max_header_size,
struct sk_buff *skb)
{
struct ircomm_cb *self = (struct ircomm_cb *)instance;
struct ircomm_info info;
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
IRDA_ASSERT(skb != NULL, return;);
IRDA_ASSERT(qos != NULL, return;);
info.max_data_size = max_seg_size;
info.max_header_size = max_header_size;
info.qos = qos;
ircomm_do_event(self, IRCOMM_LMP_CONNECT_INDICATION, skb, &info);
/* Drop reference count - see ircomm_tty_connect_indication(). */
dev_kfree_skb(skb);
}
/*
* Function ircomm_lmp_disconnect_indication (instance, sap, reason, skb)
*
* Peer device has closed the connection, or the link went down for some
* other reason
*/
static void ircomm_lmp_disconnect_indication(void *instance, void *sap,
LM_REASON reason,
struct sk_buff *skb)
{
struct ircomm_cb *self = (struct ircomm_cb *) instance;
struct ircomm_info info;
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
info.reason = reason;
ircomm_do_event(self, IRCOMM_LMP_DISCONNECT_INDICATION, skb, &info);
/* Drop reference count - see ircomm_tty_disconnect_indication(). */
if(skb)
dev_kfree_skb(skb);
}
/*
* Function ircomm_open_lsap (self)
*
* Open LSAP. This function will only be used when using "raw" services
*
*/
int ircomm_open_lsap(struct ircomm_cb *self)
{
notify_t notify;
/* Register callbacks */
irda_notify_init(¬ify);
notify.data_indication = ircomm_lmp_data_indication;
notify.connect_confirm = ircomm_lmp_connect_confirm;
notify.connect_indication = ircomm_lmp_connect_indication;
notify.disconnect_indication = ircomm_lmp_disconnect_indication;
notify.instance = self;
strlcpy(notify.name, "IrCOMM", sizeof(notify.name));
self->lsap = irlmp_open_lsap(LSAP_ANY, ¬ify, 0);
if (!self->lsap) {
pr_debug("%sfailed to allocate tsap\n", __func__);
return -1;
}
self->slsap_sel = self->lsap->slsap_sel;
/*
* Initialize the call-table for issuing commands
*/
self->issue.data_request = ircomm_lmp_data_request;
self->issue.connect_request = ircomm_lmp_connect_request;
self->issue.connect_response = ircomm_lmp_connect_response;
self->issue.disconnect_request = ircomm_lmp_disconnect_request;
return 0;
}