diff options
| author | Dharma Balasubiramani <dharma.b@microchip.com> | 2025-05-20 20:51:46 +0530 |
|---|---|---|
| committer | William Breathitt Gray <wbg@kernel.org> | 2025-05-22 18:40:19 +0900 |
| commit | ae3392c0f12f179b969ce17856ed18bf8d69a35e (patch) | |
| tree | 920c9bd7ad68d82bac45221568dc136e02d4d839 | |
| parent | ace2cd11a27231efcb8a116a597edab2eef34957 (diff) | |
counter: microchip-tcb-capture: Add watch validation support
The Timer Counter Block (TCB) exposes several kinds of events to the
Counter framework, but not every event is meaningful on every hardware
channel. Add a `watch_validate()` callback so userspace may register only
the combinations actually supported:
* Channel 0 (COUNTER_MCHP_EVCHN_CV, COUNTER_MCHP_EVCHN_RA)
- COUNTER_EVENT_CAPTURE
- COUNTER_EVENT_CHANGE_OF_STATE
- COUNTER_EVENT_OVERFLOW
* Channel 1 (COUNTER_MCHP_EVCHN_RB)
- COUNTER_EVENT_CAPTURE
* Channel 2 (COUNTER_MCHP_EVCHN_RC)
- COUNTER_EVENT_THRESHOLD
Any other request is rejected with `-EINVAL`.
Signed-off-by: Dharma Balasubiramani <dharma.b@microchip.com>
Link: https://lore.kernel.org/r/20250520-counter-tcb-v3-1-4631e2aff7ed@microchip.com
Signed-off-by: William Breathitt Gray <wbg@kernel.org>
| -rw-r--r-- | drivers/counter/microchip-tcb-capture.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c index 1de3c50b9804..1a299d1f350b 100644 --- a/drivers/counter/microchip-tcb-capture.c +++ b/drivers/counter/microchip-tcb-capture.c @@ -337,6 +337,28 @@ static struct counter_comp mchp_tc_count_ext[] = { COUNTER_COMP_COMPARE(mchp_tc_count_compare_read, mchp_tc_count_compare_write), }; +static int mchp_tc_watch_validate(struct counter_device *counter, + const struct counter_watch *watch) +{ + if (watch->channel == COUNTER_MCHP_EVCHN_CV || watch->channel == COUNTER_MCHP_EVCHN_RA) + switch (watch->event) { + case COUNTER_EVENT_CHANGE_OF_STATE: + case COUNTER_EVENT_OVERFLOW: + case COUNTER_EVENT_CAPTURE: + return 0; + default: + return -EINVAL; + } + + if (watch->channel == COUNTER_MCHP_EVCHN_RB && watch->event == COUNTER_EVENT_CAPTURE) + return 0; + + if (watch->channel == COUNTER_MCHP_EVCHN_RC && watch->event == COUNTER_EVENT_THRESHOLD) + return 0; + + return -EINVAL; +} + static struct counter_count mchp_tc_counts[] = { { .id = 0, @@ -356,7 +378,8 @@ static const struct counter_ops mchp_tc_ops = { .function_read = mchp_tc_count_function_read, .function_write = mchp_tc_count_function_write, .action_read = mchp_tc_count_action_read, - .action_write = mchp_tc_count_action_write + .action_write = mchp_tc_count_action_write, + .watch_validate = mchp_tc_watch_validate, }; static const struct atmel_tcb_config tcb_rm9200_config = { |