Adding a simple Manchester encoder to rc-core.
Manchester coding is used by at least RC-5 protocol and its variants.
Signed-off-by: Antti Seppälä <a.sepp...@gmail.com>
---
drivers/media/rc/ir-raw.c | 56 +++++++++++++++++++++++++++++++++++++++++
drivers/media/rc/rc-core-priv.h | 16 ++++++++++++
2 files changed, 72 insertions(+)
diff --git a/drivers/media/rc/ir-raw.c b/drivers/media/rc/ir-raw.c
index 9d734dd..b9cc45d 100644
--- a/drivers/media/rc/ir-raw.c
+++ b/drivers/media/rc/ir-raw.c
@@ -240,6 +240,62 @@ ir_raw_get_allowed_protocols(void)
return protocols;
}
+int ir_raw_gen_manchester(struct ir_raw_event **ev, unsigned int max,
+ const struct ir_raw_timings_manchester *timings,
+ unsigned int n, unsigned int data)
+{
+ bool need_pulse;
+ int i, count = 0;
+ i = 1 << (n - 1);
+
+ if (n > max || max < 3)
+ return -EINVAL;
+
+ if (timings->pulse_space_start) {
+ init_ir_raw_event_duration((*ev)++, 1, timings->clock);
+ init_ir_raw_event_duration((*ev), 0, timings->clock);
+ count += 2;
+ } else {
+ init_ir_raw_event_duration((*ev), 1, timings->clock);
+ count++;
+ }
+ i >>= 1;
+
+ while (i > 0) {
+ need_pulse = !(data & i);
+ if (need_pulse == !!(*ev)->pulse) {
+ (*ev)->duration += timings->clock;
+ } else {
+ init_ir_raw_event_duration(++(*ev), need_pulse,
+ timings->clock);
+ count++;
+ }
+
+ if (count >= max)
+ return -EINVAL;
+
+ init_ir_raw_event_duration(++(*ev), !need_pulse,
+ timings->clock);
+ count++;
+ i >>= 1;
+ }
+
+ if (timings->trailer_space) {
+ if (!(*ev)->pulse) {
+ (*ev)->duration += timings->trailer_space;
+ } else if (count < max) {
+ init_ir_raw_event_duration(++(*ev), 0,
+ timings->trailer_space);
+ count++;
+ } else {
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(ir_raw_gen_manchester);
+
int ir_raw_gen_pd(struct ir_raw_event **ev, unsigned int max,
const struct ir_raw_timings_pd *timings,
unsigned int n, unsigned int data)
diff --git a/drivers/media/rc/rc-core-priv.h b/drivers/media/rc/rc-core-priv.h
index 3bf8c7b..df3ab46 100644
--- a/drivers/media/rc/rc-core-priv.h
+++ b/drivers/media/rc/rc-core-priv.h
@@ -173,6 +173,22 @@ static inline void ir_raw_gen_pulse_space(struct
ir_raw_event **ev,
}
/**
+ * struct ir_raw_timings_manchester - manchester coding timings
+ * @pulse_space_start: 1 for starting with pulse (0 for starting with space)
+ * @clock: duration of each pulse/space in ns
+ * @trailer_space: duration of trailer space in ns
+ */
+struct ir_raw_timings_manchester {
+ unsigned int pulse_space_start:1;
+ unsigned int clock;
+ unsigned int trailer_space;
+};
+
+int ir_raw_gen_manchester(struct ir_raw_event **ev, unsigned int max,
+ const struct ir_raw_timings_manchester *timings,
+ unsigned int n, unsigned int data);
+
+/**
* struct ir_raw_timings_pd - pulse-distance modulation timings
* @header_pulse: duration of header pulse in ns (0 for none)
* @header_space: duration of header space in ns
--
1.8.3.2
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