zephyr/doc/connectivity
Johann Fischer c152e0980c usb: device: cdc_acm: block in uart_poll_out() routine
According to the UART API documentation, implementation must block when
the transceiver is full. For CDC ACM UART, TX ringbuffer can be
considered as transceiver buffer/FIFO. Blocking when the USB subsystem
is not ready is considered highly undesirable behavior. Blocking may
also be undesirable when CDC ACM UART is used as a logging backend.

Change the behavior of CDC ACM poll out to:
 - Block if the TX ring buffer is full, hw_flow_control property is
   enabled, and called from a non-ISR context.
 - Do not block if the USB subsystem is not ready, poll out
   implementation is called from an ISR context, or hw_flow_control
   property is disabled.

Signed-off-by: Johann Fischer <johann.fischer@nordicsemi.no>
2023-10-23 11:48:44 +02:00
..
bluetooth doc: Fix broken references to Kconfig options 2023-10-17 19:50:39 +01:00
lora_lorawan lorawan: enable run-time config of region/freq 2022-11-14 11:16:16 +00:00
networking net: lwm2m: Allow configuring update period 2023-10-20 14:57:38 +02:00
usb usb: device: cdc_acm: block in uart_poll_out() routine 2023-10-23 11:48:44 +02:00
index.rst doc: connectivity: move USB-C device stack to USB chapter 2023-06-15 05:53:44 -04:00