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authorJames Hogan2014-03-14 20:04:14 -0300
committerMauro Carvalho Chehab2017-01-30 13:52:28 -0200
commit141cfb1432f5c8e120d49229be52a32c8705afba (patch)
tree57c18d9dc7133ff42f3790b2bafc6943a2b72fe5 /drivers/media/rc/ir-nec-decoder.c
parent9d974e49339dc0ad9a6fbd7438a0887d7a445e29 (diff)
[media] rc: ir-nec-decoder: Add encode capability
Add the capability to encode NEC scancodes as raw events. The scancode_to_raw is pretty much taken from the img-ir NEC filter() callback, and modulation uses the pulse distance helper added in a previous commit. Signed-off-by: James Hogan <james@albanarts.com> Signed-off-by: Sean Young <sean@mess.org> Cc: Antti Seppälä <a.seppala@gmail.com> Cc: David Härdeman <david@hardeman.nu> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media/rc/ir-nec-decoder.c')
-rw-r--r--drivers/media/rc/ir-nec-decoder.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-nec-decoder.c b/drivers/media/rc/ir-nec-decoder.c
index a5d418e33eca..3ce850314dca 100644
--- a/drivers/media/rc/ir-nec-decoder.c
+++ b/drivers/media/rc/ir-nec-decoder.c
@@ -204,9 +204,90 @@ static int ir_nec_decode(struct rc_dev *dev, struct ir_raw_event ev)
return -EINVAL;
}
+/**
+ * ir_nec_scancode_to_raw() - encode an NEC scancode ready for modulation.
+ * @protocol: specific protocol to use
+ * @scancode: a single NEC scancode.
+ * @raw: raw data to be modulated.
+ */
+static u32 ir_nec_scancode_to_raw(enum rc_type protocol, u32 scancode)
+{
+ unsigned int addr, addr_inv, data, data_inv;
+
+ data = scancode & 0xff;
+
+ if (protocol == RC_TYPE_NEC32) {
+ /* 32-bit NEC (used by Apple and TiVo remotes) */
+ /* scan encoding: aaAAddDD */
+ addr_inv = (scancode >> 24) & 0xff;
+ addr = (scancode >> 16) & 0xff;
+ data_inv = (scancode >> 8) & 0xff;
+ } else if (protocol == RC_TYPE_NECX) {
+ /* Extended NEC */
+ /* scan encoding AAaaDD */
+ addr = (scancode >> 16) & 0xff;
+ addr_inv = (scancode >> 8) & 0xff;
+ data_inv = data ^ 0xff;
+ } else {
+ /* Normal NEC */
+ /* scan encoding: AADD */
+ addr = (scancode >> 8) & 0xff;
+ addr_inv = addr ^ 0xff;
+ data_inv = data ^ 0xff;
+ }
+
+ /* raw encoding: ddDDaaAA */
+ return data_inv << 24 |
+ data << 16 |
+ addr_inv << 8 |
+ addr;
+}
+
+static const struct ir_raw_timings_pd ir_nec_timings = {
+ .header_pulse = NEC_HEADER_PULSE,
+ .header_space = NEC_HEADER_SPACE,
+ .bit_pulse = NEC_BIT_PULSE,
+ .bit_space[0] = NEC_BIT_0_SPACE,
+ .bit_space[1] = NEC_BIT_1_SPACE,
+ .trailer_pulse = NEC_TRAILER_PULSE,
+ .trailer_space = NEC_TRAILER_SPACE,
+ .msb_first = 0,
+};
+
+/**
+ * ir_nec_encode() - Encode a scancode as a stream of raw events
+ *
+ * @protocol: protocol 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.
+ */
+static int ir_nec_encode(enum rc_type protocol, u32 scancode,
+ struct ir_raw_event *events, unsigned int max)
+{
+ struct ir_raw_event *e = events;
+ int ret;
+ u32 raw;
+
+ /* Convert a NEC scancode to raw NEC data */
+ raw = ir_nec_scancode_to_raw(protocol, scancode);
+
+ /* Modulate the raw data using a pulse distance modulation */
+ ret = ir_raw_gen_pd(&e, max, &ir_nec_timings, NEC_NBITS, raw);
+ if (ret < 0)
+ return ret;
+
+ return e - events;
+}
+
static struct ir_raw_handler nec_handler = {
.protocols = RC_BIT_NEC | RC_BIT_NECX | RC_BIT_NEC32,
.decode = ir_nec_decode,
+ .encode = ir_nec_encode,
};
static int __init ir_nec_decode_init(void)