kernel: sem: add K_SEM_MAX_LIMIT

Currently there is no way to distinguish between a caller
explicitly asking for a semaphore with a limit that
happens to be `UINT_MAX` and a semaphore that just
has a limit "as large as possible".

Add `K_SEM_MAX_LIMIT`, currently defined to `UINT_MAX`, and akin
to `K_FOREVER` versus just passing some very large wait time.

In addition, the `k_sem_*` APIs were type-confused, where
the internal data structure was `uint32_t`, but the APIs took
and returned `unsigned int`. This changes the underlying data
structure to also use `unsigned int`, as changing the APIs
would be a (potentially) breaking change.

These changes are backwards-compatible, but it is strongly suggested
to take a quick scan for `k_sem_init` and `K_SEM_DEFINE` calls with
`UINT_MAX` (or `UINT32_MAX`) and replace them with `K_SEM_MAX_LIMIT`
where appropriate.

Signed-off-by: James Harris <james.harris@intel.com>
This commit is contained in:
James Harris 2021-03-03 12:02:05 -08:00 committed by Maureen Helm
commit b10428163a
86 changed files with 110 additions and 96 deletions

View file

@ -142,7 +142,7 @@ int sx12xx_lora_test_cw(const struct device *dev, uint32_t frequency,
int sx12xx_init(const struct device *dev)
{
k_sem_init(&dev_data.data_sem, 0, UINT_MAX);
k_sem_init(&dev_data.data_sem, 0, K_SEM_MAX_LIMIT);
dev_data.events.TxDone = sx12xx_ev_tx_done;
dev_data.events.RxDone = sx12xx_ev_rx_done;