If the _IRQ_L2CAP_RECV handler does the actual consumption of the incoming
data (i.e. via l2cap_recvinto), rather than setting a flag for
non-scheduler-context to handle it later, then two things can happen:
- It can starve the VM (i.e. the scheduled task never terminates). This is
because calling l2cap_recvinto will empty the rx buffer, which will grant
more credits to the channel (an HCI command), meaning more data can
arrive. This means that the loop in hal_uart.c that keeps reading HCI
data from the uart and executing NimBLE events as they are created will
not terminate, preventing other VM code from running.
- There's no flow control (i.e. data will arrive too quickly). The channel
shouldn't be given credits until after we return from scheduler context.
It's preferable that no work is done in scheduler/IRQ context. But to
prevent this being a problem this commit changes l2cap_recvinto so that if
it is called in IRQ context, and the Python handler empties the rx buffer,
then don't grant credits until the Python handler is complete.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This allows sending arbitrary HCI commands and getting the response. The
return value of the function is the status of the command.
This is intended for debugging and not to be a part of the public API, and
must be enabled via mpconfigboard.h. It's currently only implemented for
NimBLE bindings.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This adds `_IRQ_GET_SECRET` and `_IRQ_SET_SECRET` events to allow the BT
stack to request the Python code retrive/store/delete secret key data. The
actual keys and values are opaque to Python and stack-specific.
Only NimBLE is implemented (pending moving btstack to sync events). The
secret store is designed to be compatible with BlueKitchen's TLV store API.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This allows the application to be notified if any of encrypted,
authenticated and bonded state change, as well as the encryption key size.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Enable it on STM32/Unix NimBLE only (pairing/bonding requires synchronous
events and full bindings).
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Instead of returning None/bool from the IRQ, return None/int (where a zero
value means success). This mirrors how the L2CAP_ACCEPT return value
works.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This widens the characteristic/descriptor flags to 16-bit, to allow setting
encryption/authentication requirements.
Sets the required flags for NimBLE and btstack implementations.
The BLE.FLAG_* constants will eventually be deprecated in favour of copy
and paste Python constants (like the IRQs).
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This allows the application to be notified of changes to the connection
interval, connection latency and supervision timeout.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Also known as L2CAP "connection oriented channels". This provides a
socket-like data transfer mechanism for BLE.
Currently only implemented for NimBLE on STM32 / Unix.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This changes stm32 from using PENDSV to run NimBLE to use the MicroPython
scheduler instead. This allows Python BLE callbacks to be invoked directly
(and therefore synchronously) rather than via the ringbuffer.
The NimBLE UART HCI and event processing now happens in a scheduled task
every 128ms. When RX IRQ idle events arrive, it will also schedule this
task to improve latency.
There is a similar change for the unix port where the background thread now
queues the scheduled task.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This requires that the event handlers are called from non-interrupt context
(i.e. the MicroPython scheduler).
This will allow the BLE stack (e.g. NimBLE) to run from the scheduler
rather than an IRQ like PENDSV, and therefore be able to invoke Python
callbacks directly/synchronously. This allows writing Python BLE handlers
for events that require immediate response such as _IRQ_READ_REQUEST (which
was previous a hard IRQ) and future events relating to pairing/bonding.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Using a semaphore (the previous approach) will only run the UART, whereas
for startup we need to also run the event queue.
This change makes it run the full scheduler hook.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Instead of having the stack indicate a "start", "data"..., "end", pass
through the data in one callback as an array of chunks of data.
This is because the upcoming non-ringbuffer modbluetooth implementation
cannot buffer the data in the ringbuffer and requires instead a single
callback with all the data, to pass to the Python callback.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This allows `ble.active(1)` to fail correctly if the HCI controller is
unavailable.
It also avoids an infine loop in the NimBLE event handler where NimBLE
doesn't correctly detect that the HCI controller is unavailable and keeps
trying to reset.
Furthermore, it fixes an issue where GATT service registrations were left
allocated, which led to a bad realloc if the stack was activated multiple
times.