WSL2-Linux-Kernel/drivers/misc/ibmasm/r_heartbeat.c

100 строки
2.5 KiB
C

/*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) IBM Corporation, 2004
*
* Author: Max Asböck <amax@us.ibm.com>
*
*/
#include <linux/sched.h>
#include "ibmasm.h"
#include "dot_command.h"
/*
* Reverse Heartbeat, i.e. heartbeats sent from the driver to the
* service processor.
* These heartbeats are initiated by user level programs.
*/
/* the reverse heartbeat dot command */
#pragma pack(1)
static struct {
struct dot_command_header header;
unsigned char command[3];
} rhb_dot_cmd = {
.header = {
.type = sp_read,
.command_size = 3,
.data_size = 0,
.status = 0
},
.command = { 4, 3, 6 }
};
#pragma pack()
void ibmasm_init_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb)
{
init_waitqueue_head(&rhb->wait);
rhb->stopped = 0;
}
/**
* start_reverse_heartbeat
* Loop forever, sending a reverse heartbeat dot command to the service
* processor, then sleeping. The loop comes to an end if the service
* processor fails to respond 3 times or we were interrupted.
*/
int ibmasm_start_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb)
{
struct command *cmd;
int times_failed = 0;
int result = 1;
cmd = ibmasm_new_command(sp, sizeof rhb_dot_cmd);
if (!cmd)
return -ENOMEM;
while (times_failed < 3) {
memcpy(cmd->buffer, (void *)&rhb_dot_cmd, sizeof rhb_dot_cmd);
cmd->status = IBMASM_CMD_PENDING;
ibmasm_exec_command(sp, cmd);
ibmasm_wait_for_response(cmd, IBMASM_CMD_TIMEOUT_NORMAL);
if (cmd->status != IBMASM_CMD_COMPLETE)
times_failed++;
wait_event_interruptible_timeout(rhb->wait,
rhb->stopped,
REVERSE_HEARTBEAT_TIMEOUT * HZ);
if (signal_pending(current) || rhb->stopped) {
result = -EINTR;
break;
}
}
command_put(cmd);
rhb->stopped = 0;
return result;
}
void ibmasm_stop_reverse_heartbeat(struct reverse_heartbeat *rhb)
{
rhb->stopped = 1;
wake_up_interruptible(&rhb->wait);
}