1 /* ir-sanyo-decoder.c - handle SANYO IR Pulse/Space protocol 2 * 3 * Copyright (C) 2011 by Mauro Carvalho Chehab 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation version 2 of the License. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * This protocol uses the NEC protocol timings. However, data is formatted as: 15 * 13 bits Custom Code 16 * 13 bits NOT(Custom Code) 17 * 8 bits Key data 18 * 8 bits NOT(Key data) 19 * 20 * According with LIRC, this protocol is used on Sanyo, Aiwa and Chinon 21 * Information for this protocol is available at the Sanyo LC7461 datasheet. 22 */ 23 24 #include <linux/module.h> 25 #include <linux/bitrev.h> 26 #include "rc-core-priv.h" 27 28 #define SANYO_NBITS (13+13+8+8) 29 #define SANYO_UNIT 562500 /* ns */ 30 #define SANYO_HEADER_PULSE (16 * SANYO_UNIT) 31 #define SANYO_HEADER_SPACE (8 * SANYO_UNIT) 32 #define SANYO_BIT_PULSE (1 * SANYO_UNIT) 33 #define SANYO_BIT_0_SPACE (1 * SANYO_UNIT) 34 #define SANYO_BIT_1_SPACE (3 * SANYO_UNIT) 35 #define SANYO_REPEAT_SPACE (150 * SANYO_UNIT) 36 #define SANYO_TRAILER_PULSE (1 * SANYO_UNIT) 37 #define SANYO_TRAILER_SPACE (10 * SANYO_UNIT) /* in fact, 42 */ 38 39 enum sanyo_state { 40 STATE_INACTIVE, 41 STATE_HEADER_SPACE, 42 STATE_BIT_PULSE, 43 STATE_BIT_SPACE, 44 STATE_TRAILER_PULSE, 45 STATE_TRAILER_SPACE, 46 }; 47 48 /** 49 * ir_sanyo_decode() - Decode one SANYO pulse or space 50 * @dev: the struct rc_dev descriptor of the device 51 * @duration: the struct ir_raw_event descriptor of the pulse/space 52 * 53 * This function returns -EINVAL if the pulse violates the state machine 54 */ 55 static int ir_sanyo_decode(struct rc_dev *dev, struct ir_raw_event ev) 56 { 57 struct sanyo_dec *data = &dev->raw->sanyo; 58 u32 scancode; 59 u8 address, command, not_command; 60 61 if (!(dev->enabled_protocols & RC_BIT_SANYO)) 62 return 0; 63 64 if (!is_timing_event(ev)) { 65 if (ev.reset) { 66 IR_dprintk(1, "SANYO event reset received. reset to state 0\n"); 67 data->state = STATE_INACTIVE; 68 } 69 return 0; 70 } 71 72 IR_dprintk(2, "SANYO decode started at state %d (%uus %s)\n", 73 data->state, TO_US(ev.duration), TO_STR(ev.pulse)); 74 75 switch (data->state) { 76 77 case STATE_INACTIVE: 78 if (!ev.pulse) 79 break; 80 81 if (eq_margin(ev.duration, SANYO_HEADER_PULSE, SANYO_UNIT / 2)) { 82 data->count = 0; 83 data->state = STATE_HEADER_SPACE; 84 return 0; 85 } 86 break; 87 88 89 case STATE_HEADER_SPACE: 90 if (ev.pulse) 91 break; 92 93 if (eq_margin(ev.duration, SANYO_HEADER_SPACE, SANYO_UNIT / 2)) { 94 data->state = STATE_BIT_PULSE; 95 return 0; 96 } 97 98 break; 99 100 case STATE_BIT_PULSE: 101 if (!ev.pulse) 102 break; 103 104 if (!eq_margin(ev.duration, SANYO_BIT_PULSE, SANYO_UNIT / 2)) 105 break; 106 107 data->state = STATE_BIT_SPACE; 108 return 0; 109 110 case STATE_BIT_SPACE: 111 if (ev.pulse) 112 break; 113 114 if (!data->count && geq_margin(ev.duration, SANYO_REPEAT_SPACE, SANYO_UNIT / 2)) { 115 if (!dev->keypressed) { 116 IR_dprintk(1, "SANYO discarding last key repeat: event after key up\n"); 117 } else { 118 rc_repeat(dev); 119 IR_dprintk(1, "SANYO repeat last key\n"); 120 data->state = STATE_INACTIVE; 121 } 122 return 0; 123 } 124 125 data->bits <<= 1; 126 if (eq_margin(ev.duration, SANYO_BIT_1_SPACE, SANYO_UNIT / 2)) 127 data->bits |= 1; 128 else if (!eq_margin(ev.duration, SANYO_BIT_0_SPACE, SANYO_UNIT / 2)) 129 break; 130 data->count++; 131 132 if (data->count == SANYO_NBITS) 133 data->state = STATE_TRAILER_PULSE; 134 else 135 data->state = STATE_BIT_PULSE; 136 137 return 0; 138 139 case STATE_TRAILER_PULSE: 140 if (!ev.pulse) 141 break; 142 143 if (!eq_margin(ev.duration, SANYO_TRAILER_PULSE, SANYO_UNIT / 2)) 144 break; 145 146 data->state = STATE_TRAILER_SPACE; 147 return 0; 148 149 case STATE_TRAILER_SPACE: 150 if (ev.pulse) 151 break; 152 153 if (!geq_margin(ev.duration, SANYO_TRAILER_SPACE, SANYO_UNIT / 2)) 154 break; 155 156 address = bitrev16((data->bits >> 29) & 0x1fff) >> 3; 157 /* not_address = bitrev16((data->bits >> 16) & 0x1fff) >> 3; */ 158 command = bitrev8((data->bits >> 8) & 0xff); 159 not_command = bitrev8((data->bits >> 0) & 0xff); 160 161 if ((command ^ not_command) != 0xff) { 162 IR_dprintk(1, "SANYO checksum error: received 0x%08Lx\n", 163 data->bits); 164 data->state = STATE_INACTIVE; 165 return 0; 166 } 167 168 scancode = address << 8 | command; 169 IR_dprintk(1, "SANYO scancode: 0x%06x\n", scancode); 170 rc_keydown(dev, scancode, 0); 171 data->state = STATE_INACTIVE; 172 return 0; 173 } 174 175 IR_dprintk(1, "SANYO decode failed at count %d state %d (%uus %s)\n", 176 data->count, data->state, TO_US(ev.duration), TO_STR(ev.pulse)); 177 data->state = STATE_INACTIVE; 178 return -EINVAL; 179 } 180 181 static struct ir_raw_handler sanyo_handler = { 182 .protocols = RC_BIT_SANYO, 183 .decode = ir_sanyo_decode, 184 }; 185 186 static int __init ir_sanyo_decode_init(void) 187 { 188 ir_raw_handler_register(&sanyo_handler); 189 190 printk(KERN_INFO "IR SANYO protocol handler initialized\n"); 191 return 0; 192 } 193 194 static void __exit ir_sanyo_decode_exit(void) 195 { 196 ir_raw_handler_unregister(&sanyo_handler); 197 } 198 199 module_init(ir_sanyo_decode_init); 200 module_exit(ir_sanyo_decode_exit); 201 202 MODULE_LICENSE("GPL"); 203 MODULE_AUTHOR("Mauro Carvalho Chehab"); 204 MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)"); 205 MODULE_DESCRIPTION("SANYO IR protocol decoder"); 206