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authorJames Hogan <james@albanarts.com>2015-03-31 19:48:08 +0200
committerMauro Carvalho Chehab <mchehab@s-opensource.com>2017-01-30 16:50:52 +0100
commite9ab364a28c7ada075d6983946c08363df9c8a63 (patch)
tree0c2446998dd3622de4bc33132616c910bae3d07b /drivers/media/rc/ir-rc5-decoder.c
parent[media] rc: rc-ir-raw: Add pulse-distance modulation helper (diff)
downloadlinux-e9ab364a28c7ada075d6983946c08363df9c8a63.tar.xz
linux-e9ab364a28c7ada075d6983946c08363df9c8a63.zip
[media] rc: ir-rc5-decoder: Add encode capability
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 <james@albanarts.com> Signed-off-by: Antti Seppälä <a.seppala@gmail.com> Signed-off-by: Sean Young <sean@mess.org> Cc: David Härdeman <david@hardeman.nu> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to '')
-rw-r--r--drivers/media/rc/ir-rc5-decoder.c97
1 files changed, 97 insertions, 0 deletions
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 @@ out:
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)