From e9ab364a28c7ada075d6983946c08363df9c8a63 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Tue, 31 Mar 2015 14:48:08 -0300 Subject: [PATCH] [media] rc: ir-rc5-decoder: Add encode capability MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add the capability to encode RC-5, RC-5X and RC-5-SZ scancodes as raw events. The Manchester modulation helper is used, and for RC-5X it is used twice with two sets of timings, the first with a short trailer space for the space in the middle, and the second with no leader so that it can continue the space. The encoding in RC-5-SZ first inserts a pulse and then simply utilizes the generic Manchester encoder available in rc-core. Signed-off-by: James Hogan Signed-off-by: Antti Seppälä Signed-off-by: Sean Young Cc: David Härdeman Signed-off-by: Mauro Carvalho Chehab --- drivers/media/rc/ir-rc5-decoder.c | 97 +++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) diff --git a/drivers/media/rc/ir-rc5-decoder.c b/drivers/media/rc/ir-rc5-decoder.c index 484185e5248d..fcfedf95def7 100644 --- a/drivers/media/rc/ir-rc5-decoder.c +++ b/drivers/media/rc/ir-rc5-decoder.c @@ -181,9 +181,106 @@ static int ir_rc5_decode(struct rc_dev *dev, struct ir_raw_event ev) return -EINVAL; } +static const struct ir_raw_timings_manchester ir_rc5_timings = { + .leader = RC5_UNIT, + .pulse_space_start = 0, + .clock = RC5_UNIT, + .trailer_space = RC5_UNIT * 10, +}; + +static const struct ir_raw_timings_manchester ir_rc5x_timings[2] = { + { + .leader = RC5_UNIT, + .pulse_space_start = 0, + .clock = RC5_UNIT, + .trailer_space = RC5X_SPACE, + }, + { + .clock = RC5_UNIT, + .trailer_space = RC5_UNIT * 10, + }, +}; + +static const struct ir_raw_timings_manchester ir_rc5_sz_timings = { + .leader = RC5_UNIT, + .pulse_space_start = 0, + .clock = RC5_UNIT, + .trailer_space = RC5_UNIT * 10, +}; + +/** + * ir_rc5_encode() - Encode a scancode as a stream of raw events + * + * @protocol: protocol variant to encode + * @scancode: scancode to encode + * @events: array of raw ir events to write into + * @max: maximum size of @events + * + * Returns: The number of events written. + * -ENOBUFS if there isn't enough space in the array to fit the + * encoding. In this case all @max events will have been written. + * -EINVAL if the scancode is ambiguous or invalid. + */ +static int ir_rc5_encode(enum rc_type protocol, u32 scancode, + struct ir_raw_event *events, unsigned int max) +{ + int ret; + struct ir_raw_event *e = events; + unsigned int data, xdata, command, commandx, system, pre_space_data; + + /* Detect protocol and convert scancode to raw data */ + if (protocol == RC_TYPE_RC5) { + /* decode scancode */ + command = (scancode & 0x003f) >> 0; + commandx = (scancode & 0x0040) >> 6; + system = (scancode & 0x1f00) >> 8; + /* encode data */ + data = !commandx << 12 | system << 6 | command; + + /* Modulate the data */ + ret = ir_raw_gen_manchester(&e, max, &ir_rc5_timings, + RC5_NBITS, data); + if (ret < 0) + return ret; + } else if (protocol == RC_TYPE_RC5X_20) { + /* decode scancode */ + xdata = (scancode & 0x00003f) >> 0; + command = (scancode & 0x003f00) >> 8; + commandx = !(scancode & 0x004000); + system = (scancode & 0x1f0000) >> 16; + + /* encode data */ + data = commandx << 18 | system << 12 | command << 6 | xdata; + + /* Modulate the data */ + pre_space_data = data >> (RC5X_NBITS - CHECK_RC5X_NBITS); + ret = ir_raw_gen_manchester(&e, max, &ir_rc5x_timings[0], + CHECK_RC5X_NBITS, pre_space_data); + if (ret < 0) + return ret; + ret = ir_raw_gen_manchester(&e, max - (e - events), + &ir_rc5x_timings[1], + RC5X_NBITS - CHECK_RC5X_NBITS, + data); + if (ret < 0) + return ret; + } else if (protocol == RC_TYPE_RC5_SZ) { + /* RC5-SZ scancode is raw enough for Manchester as it is */ + ret = ir_raw_gen_manchester(&e, max, &ir_rc5_sz_timings, + RC5_SZ_NBITS, scancode & 0x2fff); + if (ret < 0) + return ret; + } else { + return -EINVAL; + } + + return e - events; +} + static struct ir_raw_handler rc5_handler = { .protocols = RC_BIT_RC5 | RC_BIT_RC5X_20 | RC_BIT_RC5_SZ, .decode = ir_rc5_decode, + .encode = ir_rc5_encode, }; static int __init ir_rc5_decode_init(void)