pibridge-serdev: Minimize delays between tx data chunks [REVPI-3973]
requested to merge linosanfilippo-kunbus/linux:fix/REVPI-3973/reduce_delay_under_spinlock into revpi-6.1
Function pibridge_send() hands the transmit data to the serdev device and then calls serdev_device_wait_until_sent() to wait for the transmission to complete. This adds unnecessary delays between the header, data and CRC portion of gate or io datagrams and thus increases the time window in which a datagram can be corrupted by interferences of any kind.
Improve this situation by providing a funktion __pibridge_send() which does not call serdev_device_wait_until_sent() and use this function to send data in pibridge_req_send_gate() and pibridge_req_send_io().
Signed-off-by: Lino Sanfilippo l.sanfilippo@kunbus.com