Hi Antti,
On 08/02/14 12:07, Antti Seppälä wrote:
> 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.seppala@xxxxxxxxx>
> ---
> drivers/media/rc/ir-raw.c | 44 +++++++++++++++++++++++++++++++++++++++++
> drivers/media/rc/rc-core-priv.h | 14 +++++++++++++
> 2 files changed, 58 insertions(+)
>
> diff --git a/drivers/media/rc/ir-raw.c b/drivers/media/rc/ir-raw.c
> index 9d734dd..7fea9ac 100644
> --- a/drivers/media/rc/ir-raw.c
> +++ b/drivers/media/rc/ir-raw.c
> @@ -240,6 +240,50 @@ 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 < 2)
> + 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;
If you use pulse_space_start to encode the first bit, did you mean to
discard the highest bit of data?
> +
> + while (i > 0) {
> + if (count > max)
if count > max I think you've already overflowed the buffer (max is more
of a max count rather than max buffer index).
> + return -EINVAL;
> +
> + 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++;
I guess you need to check for buffer space here too.
> + }
> +
> + init_ir_raw_event_duration(++(*ev), !need_pulse,
> + timings->clock);
> + count++;
> + i >>= 1;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(ir_raw_gen_manchester);
Cheers
James
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