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Diffstat (limited to 'kernel/Documentation/input/rotary-encoder.txt')
| -rw-r--r-- | kernel/Documentation/input/rotary-encoder.txt | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/kernel/Documentation/input/rotary-encoder.txt b/kernel/Documentation/input/rotary-encoder.txt index 92e68bce1..46a74f0c5 100644 --- a/kernel/Documentation/input/rotary-encoder.txt +++ b/kernel/Documentation/input/rotary-encoder.txt @@ -9,8 +9,9 @@ peripherals with two wires. The outputs are phase-shifted by 90 degrees and by triggering on falling and rising edges, the turn direction can be determined. -Some encoders have both outputs low in stable states, whereas others also have -a stable state with both outputs high (half-period mode). +Some encoders have both outputs low in stable states, others also have +a stable state with both outputs high (half-period mode) and some have +a stable state in all steps (quarter-period mode). The phase diagram of these two outputs look like this: @@ -32,8 +33,11 @@ The phase diagram of these two outputs look like this: |<-->| one step (half-period mode) + |<>| + one step (quarter-period mode) + For more information, please see - http://en.wikipedia.org/wiki/Rotary_encoder + https://en.wikipedia.org/wiki/Rotary_encoder 1. Events / state machine @@ -109,6 +113,7 @@ static struct rotary_encoder_platform_data my_rotary_encoder_info = { .inverted_a = 0, .inverted_b = 0, .half_period = false, + .wakeup_source = false, }; static struct platform_device rotary_encoder_device = { |