1 // SPDX-License-Identifier: GPL-2.0-only
2 /* ir-jvc-decoder.c - handle JVC IR Pulse/Space protocol
9 #include "rc-core-priv.h"
12 #define JVC_UNIT		525		/* us */
13 #define JVC_HEADER_PULSE	(16 * JVC_UNIT) /* lack of header -> repeat */
32  * ir_jvc_decode() - Decode one JVC pulse or space
36  * This function returns -EINVAL if the pulse violates the state machine
40 	struct jvc_dec *data = &dev->raw->jvc;  in ir_jvc_decode()
44 			data->state = STATE_INACTIVE;  in ir_jvc_decode()
48 	if (!geq_margin(ev.duration, JVC_UNIT, JVC_UNIT / 2))  in ir_jvc_decode()
51 	dev_dbg(&dev->dev, "JVC decode started at state %d (%uus %s)\n",  in ir_jvc_decode()
52 		data->state, ev.duration, TO_STR(ev.pulse));  in ir_jvc_decode()
55 	switch (data->state) {  in ir_jvc_decode()
61 		if (!eq_margin(ev.duration, JVC_HEADER_PULSE, JVC_UNIT / 2))  in ir_jvc_decode()
64 		data->count = 0;  in ir_jvc_decode()
65 		data->first = true;  in ir_jvc_decode()
66 		data->toggle = !data->toggle;  in ir_jvc_decode()
67 		data->state = STATE_HEADER_SPACE;  in ir_jvc_decode()
74 		if (!eq_margin(ev.duration, JVC_HEADER_SPACE, JVC_UNIT / 2))  in ir_jvc_decode()
77 		data->state = STATE_BIT_PULSE;  in ir_jvc_decode()
84 		if (!eq_margin(ev.duration, JVC_BIT_PULSE, JVC_UNIT / 2))  in ir_jvc_decode()
87 		data->state = STATE_BIT_SPACE;  in ir_jvc_decode()
94 		data->bits <<= 1;  in ir_jvc_decode()
95 		if (eq_margin(ev.duration, JVC_BIT_1_SPACE, JVC_UNIT / 2)) {  in ir_jvc_decode()
96 			data->bits |= 1;  in ir_jvc_decode()
98 		} else if (eq_margin(ev.duration, JVC_BIT_0_SPACE, JVC_UNIT / 2))  in ir_jvc_decode()
102 		data->count++;  in ir_jvc_decode()
104 		if (data->count == JVC_NBITS)  in ir_jvc_decode()
105 			data->state = STATE_TRAILER_PULSE;  in ir_jvc_decode()
107 			data->state = STATE_BIT_PULSE;  in ir_jvc_decode()
114 		if (!eq_margin(ev.duration, JVC_TRAILER_PULSE, JVC_UNIT / 2))  in ir_jvc_decode()
117 		data->state = STATE_TRAILER_SPACE;  in ir_jvc_decode()
124 		if (!geq_margin(ev.duration, JVC_TRAILER_SPACE, JVC_UNIT / 2))  in ir_jvc_decode()
127 		if (data->first) {  in ir_jvc_decode()
129 			scancode = (bitrev8((data->bits >> 8) & 0xff) << 8) |  in ir_jvc_decode()
130 				   (bitrev8((data->bits >> 0) & 0xff) << 0);  in ir_jvc_decode()
131 			dev_dbg(&dev->dev, "JVC scancode 0x%04x\n", scancode);  in ir_jvc_decode()
132 			rc_keydown(dev, RC_PROTO_JVC, scancode, data->toggle);  in ir_jvc_decode()
133 			data->first = false;  in ir_jvc_decode()
134 			data->old_bits = data->bits;  in ir_jvc_decode()
135 		} else if (data->bits == data->old_bits) {  in ir_jvc_decode()
136 			dev_dbg(&dev->dev, "JVC repeat\n");  in ir_jvc_decode()
139 			dev_dbg(&dev->dev, "JVC invalid repeat msg\n");  in ir_jvc_decode()
143 		data->count = 0;  in ir_jvc_decode()
144 		data->state = STATE_CHECK_REPEAT;  in ir_jvc_decode()
151 		if (eq_margin(ev.duration, JVC_HEADER_PULSE, JVC_UNIT / 2))  in ir_jvc_decode()
152 			data->state = STATE_INACTIVE;  in ir_jvc_decode()
154 			data->state = STATE_BIT_PULSE;  in ir_jvc_decode()
159 	dev_dbg(&dev->dev, "JVC decode failed at state %d (%uus %s)\n",  in ir_jvc_decode()
160 		data->state, ev.duration, TO_STR(ev.pulse));  in ir_jvc_decode()
161 	data->state = STATE_INACTIVE;  in ir_jvc_decode()
162 	return -EINVAL;  in ir_jvc_decode()
177  * ir_jvc_encode() - Encode a scancode as a stream of raw events
185  *		-ENOBUFS if there isn't enough space in the array to fit the
200 	return e - events;  in ir_jvc_encode()