kernel_optimize_test/include/linux/hil_mlc.h
Helge Deller 879bc2d279 hil/parisc: Disable HIL driver when it gets stuck
When starting a HP machine with HIL driver but without an HIL keyboard
or HIL mouse attached, it may happen that data written to the HIL loop
gets stuck (e.g. because the transaction queue is full).  Usually one
will then have to reboot the machine because all you see is and endless
output of:
 Transaction add failed: transaction already queued?

In the higher layers hp_sdc_enqueue_transaction() is called to queued up
a HIL packet. This function returns an error code, and this patch adds
the necessary checks for this return code and disables the HIL driver if
further packets can't be sent.

Tested on a HP 730 and a HP 715/64 machine.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
2020-10-22 22:44:35 +02:00

169 lines
5.1 KiB
C

/*
* 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 int (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;
unsigned long instart;
unsigned long intimeout;
int ddi; /* Last operational device id */
int lcv; /* LCV to throttle loops */
time64_t lcv_time; /* 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);