diff options
| -rw-r--r-- | drivers/media/rc/rc-core-priv.h | 33 | ||||
| -rw-r--r-- | drivers/media/rc/rc-ir-raw.c | 85 |
2 files changed, 118 insertions, 0 deletions
diff --git a/drivers/media/rc/rc-core-priv.h b/drivers/media/rc/rc-core-priv.h index 122c25fe91e0..5266ecc73f05 100644 --- a/drivers/media/rc/rc-core-priv.h +++ b/drivers/media/rc/rc-core-priv.h @@ -152,6 +152,39 @@ static inline bool is_timing_event(struct ir_raw_event ev) #define TO_US(duration) DIV_ROUND_CLOSEST((duration), 1000) #define TO_STR(is_pulse) ((is_pulse) ? "pulse" : "space") +/* functions for IR encoders */ + +static inline void init_ir_raw_event_duration(struct ir_raw_event *ev, + unsigned int pulse, + u32 duration) +{ + init_ir_raw_event(ev); + ev->duration = duration; + ev->pulse = pulse; +} + +/** + * struct ir_raw_timings_manchester - Manchester coding timings + * @leader: duration of leader pulse (if any) 0 if continuing + * existing signal (see @pulse_space_start) + * @pulse_space_start: 1 for starting with pulse (0 for starting with space) + * @clock: duration of each pulse/space in ns + * @invert: if set clock logic is inverted + * (0 = space + pulse, 1 = pulse + space) + * @trailer_space: duration of trailer space in ns + */ +struct ir_raw_timings_manchester { + unsigned int leader; + unsigned int pulse_space_start:1; + unsigned int clock; + unsigned int invert:1; + 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); + /* * Routines from rc-raw.c to be used internally and by decoders */ diff --git a/drivers/media/rc/rc-ir-raw.c b/drivers/media/rc/rc-ir-raw.c index dd47fe567f03..6c9580e4cac5 100644 --- a/drivers/media/rc/rc-ir-raw.c +++ b/drivers/media/rc/rc-ir-raw.c @@ -247,6 +247,91 @@ static int change_protocol(struct rc_dev *dev, u64 *rc_type) } /** + * ir_raw_gen_manchester() - Encode data with Manchester (bi-phase) modulation. + * @ev: Pointer to pointer to next free event. *@ev is incremented for + * each raw event filled. + * @max: Maximum number of raw events to fill. + * @timings: Manchester modulation timings. + * @n: Number of bits of data. + * @data: Data bits to encode. + * + * Encodes the @n least significant bits of @data using Manchester (bi-phase) + * modulation with the timing characteristics described by @timings, writing up + * to @max raw IR events using the *@ev pointer. + * + * Returns: 0 on success. + * -ENOBUFS if there isn't enough space in the array to fit the + * full encoded data. In this case all @max events will have been + * written. + */ +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; + unsigned int i; + int ret = -ENOBUFS; + + i = 1 << (n - 1); + + if (timings->leader) { + if (!max--) + return ret; + if (timings->pulse_space_start) { + init_ir_raw_event_duration((*ev)++, 1, timings->leader); + + if (!max--) + return ret; + init_ir_raw_event_duration((*ev), 0, timings->leader); + } else { + init_ir_raw_event_duration((*ev), 1, timings->leader); + } + i >>= 1; + } else { + /* continue existing signal */ + --(*ev); + } + /* from here on *ev will point to the last event rather than the next */ + + while (n && i > 0) { + need_pulse = !(data & i); + if (timings->invert) + need_pulse = !need_pulse; + if (need_pulse == !!(*ev)->pulse) { + (*ev)->duration += timings->clock; + } else { + if (!max--) + goto nobufs; + init_ir_raw_event_duration(++(*ev), need_pulse, + timings->clock); + } + + if (!max--) + goto nobufs; + init_ir_raw_event_duration(++(*ev), !need_pulse, + timings->clock); + i >>= 1; + } + + if (timings->trailer_space) { + if (!(*ev)->pulse) + (*ev)->duration += timings->trailer_space; + else if (!max--) + goto nobufs; + else + init_ir_raw_event_duration(++(*ev), 0, + timings->trailer_space); + } + + ret = 0; +nobufs: + /* point to the next event rather than last event before returning */ + ++(*ev); + return ret; +} +EXPORT_SYMBOL(ir_raw_gen_manchester); + +/** * ir_raw_encode_scancode() - Encode a scancode as raw events * * @protocols: permitted protocols |