1 /* 2 * HP Human Interface Loop Master Link Controller driver. 3 * 4 * Copyright (c) 2001 Brian S. Julin 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions, and the following disclaimer, 12 * without modification. 13 * 2. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * Alternatively, this software may be distributed under the terms of the 17 * GNU General Public License ("GPL"). 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 23 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * 29 * References: 30 * HP-HIL Technical Reference Manual. Hewlett Packard Product No. 45918A 31 * 32 */ 33 34 #include <linux/hil.h> 35 #include <linux/time.h> 36 #include <linux/interrupt.h> 37 #include <linux/semaphore.h> 38 #include <linux/serio.h> 39 #include <linux/list.h> 40 41 typedef struct hil_mlc hil_mlc; 42 43 /* The HIL has a complicated state engine. 44 * We define the structure of nodes in the state engine here. 45 */ 46 enum hilse_act { 47 /* HILSE_OUT prepares to receive input if the next node 48 * is an IN or EXPECT, and then sends the given packet. 49 */ 50 HILSE_OUT = 0, 51 52 /* HILSE_CTS checks if the loop is busy. */ 53 HILSE_CTS, 54 55 /* HILSE_OUT_LAST sends the given command packet to 56 * the last configured/running device on the loop. 57 */ 58 HILSE_OUT_LAST, 59 60 /* HILSE_OUT_DISC sends the given command packet to 61 * the next device past the last configured/running one. 62 */ 63 HILSE_OUT_DISC, 64 65 /* HILSE_FUNC runs a callback function with given arguments. 66 * a positive return value causes the "ugly" branch to be taken. 67 */ 68 HILSE_FUNC, 69 70 /* HILSE_IN simply expects any non-errored packet to arrive 71 * within arg usecs. 72 */ 73 HILSE_IN = 0x100, 74 75 /* HILSE_EXPECT expects a particular packet to arrive 76 * within arg usecs, any other packet is considered an error. 77 */ 78 HILSE_EXPECT, 79 80 /* HILSE_EXPECT_LAST as above but dev field should be last 81 * discovered/operational device. 82 */ 83 HILSE_EXPECT_LAST, 84 85 /* HILSE_EXPECT_LAST as above but dev field should be first 86 * undiscovered/inoperational device. 87 */ 88 HILSE_EXPECT_DISC 89 }; 90 91 typedef int (hilse_func) (hil_mlc *mlc, int arg); 92 struct hilse_node { 93 enum hilse_act act; /* How to process this node */ 94 union { 95 hilse_func *func; /* Function to call if HILSE_FUNC */ 96 hil_packet packet; /* Packet to send or to compare */ 97 } object; 98 int arg; /* Timeout in usec or parm for func */ 99 int good; /* Node to jump to on success */ 100 int bad; /* Node to jump to on error */ 101 int ugly; /* Node to jump to on timeout */ 102 }; 103 104 /* Methods for back-end drivers, e.g. hp_sdc_mlc */ 105 typedef int (hil_mlc_cts) (hil_mlc *mlc); 106 typedef void (hil_mlc_out) (hil_mlc *mlc); 107 typedef int (hil_mlc_in) (hil_mlc *mlc, suseconds_t timeout); 108 109 struct hil_mlc_devinfo { 110 uint8_t idd[16]; /* Device ID Byte and Describe Record */ 111 uint8_t rsc[16]; /* Security Code Header and Record */ 112 uint8_t exd[16]; /* Extended Describe Record */ 113 uint8_t rnm[16]; /* Device name as returned by RNM command */ 114 }; 115 116 struct hil_mlc_serio_map { 117 hil_mlc *mlc; 118 int di_revmap; 119 int didx; 120 }; 121 122 /* How many (possibly old/detached) devices the we try to keep track of */ 123 #define HIL_MLC_DEVMEM 16 124 125 struct hil_mlc { 126 struct list_head list; /* hil_mlc is organized as linked list */ 127 128 rwlock_t lock; 129 130 void *priv; /* Data specific to a particular type of MLC */ 131 132 int seidx; /* Current node in state engine */ 133 int istarted, ostarted; 134 135 hil_mlc_cts *cts; 136 struct semaphore csem; /* Raised when loop idle */ 137 138 hil_mlc_out *out; 139 struct semaphore osem; /* Raised when outpacket dispatched */ 140 hil_packet opacket; 141 142 hil_mlc_in *in; 143 struct semaphore isem; /* Raised when a packet arrives */ 144 hil_packet ipacket[16]; 145 hil_packet imatch; 146 int icount; 147 struct timeval instart; 148 suseconds_t intimeout; 149 150 int ddi; /* Last operational device id */ 151 int lcv; /* LCV to throttle loops */ 152 struct timeval lcv_tv; /* Time loop was started */ 153 154 int di_map[7]; /* Maps below items to live devs */ 155 struct hil_mlc_devinfo di[HIL_MLC_DEVMEM]; 156 struct serio *serio[HIL_MLC_DEVMEM]; 157 struct hil_mlc_serio_map serio_map[HIL_MLC_DEVMEM]; 158 hil_packet serio_opacket[HIL_MLC_DEVMEM]; 159 int serio_oidx[HIL_MLC_DEVMEM]; 160 struct hil_mlc_devinfo di_scratch; /* Temporary area */ 161 162 int opercnt; 163 164 struct tasklet_struct *tasklet; 165 }; 166 167 int hil_mlc_register(hil_mlc *mlc); 168 int hil_mlc_unregister(hil_mlc *mlc); 169