1 // SPDX-License-Identifier: GPL-2.0
2 // ir-rc5-decoder.c - decoder for RC5(x) and StreamZap protocols
12 #include "rc-core-priv.h"
34  * ir_rc5_decode() - Decode one RC-5 pulse or space
38  * This function returns -EINVAL if the pulse violates the state machine
42 	struct rc5_dec *data = &dev->raw->rc5;  in ir_rc5_decode()  local
49 			data->state = STATE_INACTIVE;  in ir_rc5_decode()
57 	dev_dbg(&dev->dev, "RC5(x/sz) decode started at state %i (%uus %s)\n",  in ir_rc5_decode()
58 		data->state, ev.duration, TO_STR(ev.pulse));  in ir_rc5_decode()
63 	switch (data->state) {  in ir_rc5_decode()
69 		data->state = STATE_BIT_START;  in ir_rc5_decode()
70 		data->count = 1;  in ir_rc5_decode()
76 			data->state = STATE_FINISHED;  in ir_rc5_decode()
83 		data->bits <<= 1;  in ir_rc5_decode()
85 			data->bits |= 1;  in ir_rc5_decode()
86 		data->count++;  in ir_rc5_decode()
87 		data->state = STATE_BIT_END;  in ir_rc5_decode()
91 		if (data->count == CHECK_RC5X_NBITS)  in ir_rc5_decode()
92 			data->state = STATE_CHECK_RC5X;  in ir_rc5_decode()
94 			data->state = STATE_BIT_START;  in ir_rc5_decode()
101 			data->is_rc5x = true;  in ir_rc5_decode()
104 			data->is_rc5x = false;  in ir_rc5_decode()
105 		data->state = STATE_BIT_START;  in ir_rc5_decode()
112 		if (data->is_rc5x && data->count == RC5X_NBITS) {  in ir_rc5_decode()
115 			if (!(dev->enabled_protocols & RC_PROTO_BIT_RC5X_20)) {  in ir_rc5_decode()
116 				data->state = STATE_INACTIVE;  in ir_rc5_decode()
119 			xdata    = (data->bits & 0x0003F) >> 0;  in ir_rc5_decode()
120 			command  = (data->bits & 0x00FC0) >> 6;  in ir_rc5_decode()
121 			system   = (data->bits & 0x1F000) >> 12;  in ir_rc5_decode()
122 			toggle   = (data->bits & 0x20000) ? 1 : 0;  in ir_rc5_decode()
123 			command += (data->bits & 0x40000) ? 0 : 0x40;  in ir_rc5_decode()
127 		} else if (!data->is_rc5x && data->count == RC5_NBITS) {  in ir_rc5_decode()
130 			if (!(dev->enabled_protocols & RC_PROTO_BIT_RC5)) {  in ir_rc5_decode()
131 				data->state = STATE_INACTIVE;  in ir_rc5_decode()
134 			command  = (data->bits & 0x0003F) >> 0;  in ir_rc5_decode()
135 			system   = (data->bits & 0x007C0) >> 6;  in ir_rc5_decode()
136 			toggle   = (data->bits & 0x00800) ? 1 : 0;  in ir_rc5_decode()
137 			command += (data->bits & 0x01000) ? 0 : 0x40;  in ir_rc5_decode()
141 		} else if (!data->is_rc5x && data->count == RC5_SZ_NBITS) {  in ir_rc5_decode()
144 			if (!(dev->enabled_protocols & RC_PROTO_BIT_RC5_SZ)) {  in ir_rc5_decode()
145 				data->state = STATE_INACTIVE;  in ir_rc5_decode()
148 			command  = (data->bits & 0x0003F) >> 0;  in ir_rc5_decode()
149 			system   = (data->bits & 0x02FC0) >> 6;  in ir_rc5_decode()
150 			toggle   = (data->bits & 0x01000) ? 1 : 0;  in ir_rc5_decode()
157 		dev_dbg(&dev->dev, "RC5(x/sz) scancode 0x%06x (p: %u, t: %u)\n",  in ir_rc5_decode()
161 		data->state = STATE_INACTIVE;  in ir_rc5_decode()
166 	dev_dbg(&dev->dev, "RC5(x/sz) decode failed at state %i count %d (%uus %s)\n",  in ir_rc5_decode()
167 		data->state, data->count, ev.duration, TO_STR(ev.pulse));  in ir_rc5_decode()
168 	data->state = STATE_INACTIVE;  in ir_rc5_decode()
169 	return -EINVAL;  in ir_rc5_decode()
197  * ir_rc5_encode() - Encode a scancode as a stream of raw events
205  *		-ENOBUFS if there isn't enough space in the array to fit the
207  *		-EINVAL if the scancode is ambiguous or invalid.
214 	unsigned int data, xdata, command, commandx, system, pre_space_data;  in ir_rc5_encode()  local
216 	/* Detect protocol and convert scancode to raw data */  in ir_rc5_encode()
222 		/* encode data */  in ir_rc5_encode()
223 		data = !commandx << 12 | system << 6 | command;  in ir_rc5_encode()
227 					    RC5_NBITS - 1, data);  in ir_rc5_encode()
237 		/* encode data */  in ir_rc5_encode()
238 		data = commandx << 18 | system << 12 | command << 6 | xdata;  in ir_rc5_encode()
241 		pre_space_data = data >> (RC5X_NBITS - CHECK_RC5X_NBITS);  in ir_rc5_encode()
243 					    CHECK_RC5X_NBITS - 1,  in ir_rc5_encode()
247 		ret = ir_raw_gen_manchester(&e, max - (e - events),  in ir_rc5_encode()
249 					    RC5X_NBITS - CHECK_RC5X_NBITS,  in ir_rc5_encode()
250 					    data);  in ir_rc5_encode()
254 		/* RC5-SZ scancode is raw enough for Manchester as it is */  in ir_rc5_encode()
257 					    RC5_SZ_NBITS - 1,  in ir_rc5_encode()
262 		return -EINVAL;  in ir_rc5_encode()
265 	return e - events;  in ir_rc5_encode()