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 u16 address; 60 u8 command, not_command; 61 62 if (!is_timing_event(ev)) { 63 if (ev.reset) { 64 IR_dprintk(1, "SANYO event reset received. reset to state 0\n"); 65 data->state = STATE_INACTIVE; 66 } 67 return 0; 68 } 69 70 IR_dprintk(2, "SANYO decode started at state %d (%uus %s)\n", 71 data->state, TO_US(ev.duration), TO_STR(ev.pulse)); 72 73 switch (data->state) { 74 75 case STATE_INACTIVE: 76 if (!ev.pulse) 77 break; 78 79 if (eq_margin(ev.duration, SANYO_HEADER_PULSE, SANYO_UNIT / 2)) { 80 data->count = 0; 81 data->state = STATE_HEADER_SPACE; 82 return 0; 83 } 84 break; 85 86 87 case STATE_HEADER_SPACE: 88 if (ev.pulse) 89 break; 90 91 if (eq_margin(ev.duration, SANYO_HEADER_SPACE, SANYO_UNIT / 2)) { 92 data->state = STATE_BIT_PULSE; 93 return 0; 94 } 95 96 break; 97 98 case STATE_BIT_PULSE: 99 if (!ev.pulse) 100 break; 101 102 if (!eq_margin(ev.duration, SANYO_BIT_PULSE, SANYO_UNIT / 2)) 103 break; 104 105 data->state = STATE_BIT_SPACE; 106 return 0; 107 108 case STATE_BIT_SPACE: 109 if (ev.pulse) 110 break; 111 112 if (!data->count && geq_margin(ev.duration, SANYO_REPEAT_SPACE, SANYO_UNIT / 2)) { 113 if (!dev->keypressed) { 114 IR_dprintk(1, "SANYO discarding last key repeat: event after key up\n"); 115 } else { 116 rc_repeat(dev); 117 IR_dprintk(1, "SANYO repeat last key\n"); 118 data->state = STATE_INACTIVE; 119 } 120 return 0; 121 } 122 123 data->bits <<= 1; 124 if (eq_margin(ev.duration, SANYO_BIT_1_SPACE, SANYO_UNIT / 2)) 125 data->bits |= 1; 126 else if (!eq_margin(ev.duration, SANYO_BIT_0_SPACE, SANYO_UNIT / 2)) 127 break; 128 data->count++; 129 130 if (data->count == SANYO_NBITS) 131 data->state = STATE_TRAILER_PULSE; 132 else 133 data->state = STATE_BIT_PULSE; 134 135 return 0; 136 137 case STATE_TRAILER_PULSE: 138 if (!ev.pulse) 139 break; 140 141 if (!eq_margin(ev.duration, SANYO_TRAILER_PULSE, SANYO_UNIT / 2)) 142 break; 143 144 data->state = STATE_TRAILER_SPACE; 145 return 0; 146 147 case STATE_TRAILER_SPACE: 148 if (ev.pulse) 149 break; 150 151 if (!geq_margin(ev.duration, SANYO_TRAILER_SPACE, SANYO_UNIT / 2)) 152 break; 153 154 address = bitrev16((data->bits >> 29) & 0x1fff) >> 3; 155 /* not_address = bitrev16((data->bits >> 16) & 0x1fff) >> 3; */ 156 command = bitrev8((data->bits >> 8) & 0xff); 157 not_command = bitrev8((data->bits >> 0) & 0xff); 158 159 if ((command ^ not_command) != 0xff) { 160 IR_dprintk(1, "SANYO checksum error: received 0x%08Lx\n", 161 data->bits); 162 data->state = STATE_INACTIVE; 163 return 0; 164 } 165 166 scancode = address << 8 | command; 167 IR_dprintk(1, "SANYO scancode: 0x%06x\n", scancode); 168 rc_keydown(dev, RC_TYPE_SANYO, scancode, 0); 169 data->state = STATE_INACTIVE; 170 return 0; 171 } 172 173 IR_dprintk(1, "SANYO decode failed at count %d state %d (%uus %s)\n", 174 data->count, data->state, TO_US(ev.duration), TO_STR(ev.pulse)); 175 data->state = STATE_INACTIVE; 176 return -EINVAL; 177 } 178 179 static struct ir_raw_handler sanyo_handler = { 180 .protocols = RC_BIT_SANYO, 181 .decode = ir_sanyo_decode, 182 }; 183 184 static int __init ir_sanyo_decode_init(void) 185 { 186 ir_raw_handler_register(&sanyo_handler); 187 188 printk(KERN_INFO "IR SANYO protocol handler initialized\n"); 189 return 0; 190 } 191 192 static void __exit ir_sanyo_decode_exit(void) 193 { 194 ir_raw_handler_unregister(&sanyo_handler); 195 } 196 197 module_init(ir_sanyo_decode_init); 198 module_exit(ir_sanyo_decode_exit); 199 200 MODULE_LICENSE("GPL"); 201 MODULE_AUTHOR("Mauro Carvalho Chehab"); 202 MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)"); 203 MODULE_DESCRIPTION("SANYO IR protocol decoder"); 204