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/*
* HP Human Interface Loop Master Link Controller driver.
*
* Copyright (c) 2001 Brian S. Julin
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL").
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
*
* References:
* HP-HIL Technical Reference Manual. Hewlett Packard Product No. 45918A
*
*/
#include <linux/hil.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/semaphore.h>
#include <linux/serio.h>
#include <linux/list.h>
typedef struct hil_mlc hil_mlc;
/* The HIL has a complicated state engine.
* We define the structure of nodes in the state engine here.
*/
enum hilse_act {
/* HILSE_OUT prepares to receive input if the next node
* is an IN or EXPECT, and then sends the given packet.
*/
HILSE_OUT = 0,
/* HILSE_CTS checks if the loop is busy. */
HILSE_CTS,
/* HILSE_OUT_LAST sends the given command packet to
* the last configured/running device on the loop.
*/
HILSE_OUT_LAST,
/* HILSE_OUT_DISC sends the given command packet to
* the next device past the last configured/running one.
*/
HILSE_OUT_DISC,
/* HILSE_FUNC runs a callback function with given arguments.
* a positive return value causes the "ugly" branch to be taken.
*/
HILSE_FUNC,
/* HILSE_IN simply expects any non-errored packet to arrive
* within arg usecs.
*/
HILSE_IN = 0x100,
/* HILSE_EXPECT expects a particular packet to arrive
* within arg usecs, any other packet is considered an error.
*/
HILSE_EXPECT,
/* HILSE_EXPECT_LAST as above but dev field should be last
* discovered/operational device.
*/
HILSE_EXPECT_LAST,
/* HILSE_EXPECT_LAST as above but dev field should be first
* undiscovered/inoperational device.
*/
HILSE_EXPECT_DISC
};
typedef int (hilse_func) (hil_mlc *mlc, int arg);
struct hilse_node {
enum hilse_act act; /* How to process this node */
union {
hilse_func *func; /* Function to call if HILSE_FUNC */
hil_packet packet; /* Packet to send or to compare */
} object;
int arg; /* Timeout in usec or parm for func */
int good; /* Node to jump to on success */
int bad; /* Node to jump to on error */
int ugly; /* Node to jump to on timeout */
};
/* Methods for back-end drivers, e.g. hp_sdc_mlc */
typedef int (hil_mlc_cts) (hil_mlc *mlc);
typedef void (hil_mlc_out) (hil_mlc *mlc);
typedef int (hil_mlc_in) (hil_mlc *mlc, suseconds_t timeout);
struct hil_mlc_devinfo {
uint8_t idd[16]; /* Device ID Byte and Describe Record */
uint8_t rsc[16]; /* Security Code Header and Record */
uint8_t exd[16]; /* Extended Describe Record */
uint8_t rnm[16]; /* Device name as returned by RNM command */
};
struct hil_mlc_serio_map {
hil_mlc *mlc;
int di_revmap;
int didx;
};
/* How many (possibly old/detached) devices the we try to keep track of */
#define HIL_MLC_DEVMEM 16
struct hil_mlc {
struct list_head list; /* hil_mlc is organized as linked list */
rwlock_t lock;
void *priv; /* Data specific to a particular type of MLC */
int seidx; /* Current node in state engine */
int istarted, ostarted;
hil_mlc_cts *cts;
struct semaphore csem; /* Raised when loop idle */
hil_mlc_out *out;
struct semaphore osem; /* Raised when outpacket dispatched */
hil_packet opacket;
hil_mlc_in *in;
struct semaphore isem; /* Raised when a packet arrives */
hil_packet ipacket[16];
hil_packet imatch;
int icount;
struct timeval instart;
suseconds_t intimeout;
int ddi; /* Last operational device id */
int lcv; /* LCV to throttle loops */
struct timeval lcv_tv; /* Time loop was started */
int di_map[7]; /* Maps below items to live devs */
struct hil_mlc_devinfo di[HIL_MLC_DEVMEM];
struct serio *serio[HIL_MLC_DEVMEM];
struct hil_mlc_serio_map serio_map[HIL_MLC_DEVMEM];
hil_packet serio_opacket[HIL_MLC_DEVMEM];
int serio_oidx[HIL_MLC_DEVMEM];
struct hil_mlc_devinfo di_scratch; /* Temporary area */
int opercnt;
struct tasklet_struct *tasklet;
};
int hil_mlc_register(hil_mlc *mlc);
int hil_mlc_unregister(hil_mlc *mlc);