networking/caif/caif.rst

1 .. SPDX-License-Identifier: GPL-2.0
10 :Copyright: |copy| ST-Ericsson AB 2010
40 The use of Start-of-frame-extension (STX) must also be set as
59 /sys/kernel/debug/caif_serial/<tty-name>/
61 * ser_state:   Prints the bit-mask status where
63   - 0x02 means SENDING, this is a transient state.
64   - 0x10 means FLOW_OFF_SENT, i.e. the previous frame has not been sent
65     and is blocking further send operation. Flow OFF has been propagated
68 * tty_status: Prints the bit-mask tty status information
70   - 0x01 - tty->warned is on.
71   - 0x04 - tty->packed is on.
72   - 0x08 - tty->flow.tco_stopped is on.
73   - 0x10 - tty->hw_stopped is on.
74   - 0x20 - tty->flow.stopped is on.
80 	$od --format=x1 /sys/kernel/debug/caif_serial/<tty>/last_rx_msg.
83   byte 02 is start of frame extension (STX) used for re-syncing
86   - Enumeration::
94                                 Link-ID(1)
97   - Channel Setup::
106                                     Priority and Link-ID(1)
123 - last_tx_msg contains channel setup message and last_rx_msg is empty ->
124   The host seems to be able to send over the UART, at least the CAIF ldisc get
127 - last_tx_msg contains enumeration message and last_rx_msg is empty ->
128   The host is not able to send the message from UART, the tty has not been
131 - if /sys/kernel/debug/caif_serial/<tty>/tty_status is non-zero there
134   E.g. host and modem wiring is not correct you will typically see
138   and empty last_rx_message.