diff options
Diffstat (limited to 'Documentation/serial/driver')
| -rw-r--r-- | Documentation/serial/driver | 44 |
1 files changed, 41 insertions, 3 deletions
diff --git a/Documentation/serial/driver b/Documentation/serial/driver index 0a25a9191864..067c47d46917 100644 --- a/Documentation/serial/driver +++ b/Documentation/serial/driver @@ -133,6 +133,16 @@ hardware. Interrupts: locally disabled. This call must not sleep + send_xchar(port,ch) + Transmit a high priority character, even if the port is stopped. + This is used to implement XON/XOFF flow control and tcflow(). If + the serial driver does not implement this function, the tty core + will append the character to the circular buffer and then call + start_tx() / stop_tx() to flush the data out. + + Locking: none. + Interrupts: caller dependent. + stop_rx(port) Stop receiving characters; the port is in the process of being closed. @@ -242,9 +252,8 @@ hardware. pm(port,state,oldstate) Perform any power management related activities on the specified - port. State indicates the new state (defined by ACPI D0-D3), - oldstate indicates the previous state. Essentially, D0 means - fully on, D3 means powered down. + port. State indicates the new state (defined by + enum uart_pm_state), oldstate indicates the previous state. This function should not be used to grab any resources. @@ -255,6 +264,10 @@ hardware. Locking: none. Interrupts: caller dependent. + set_wake(port,state) + Enable/disable power management wakeup on serial activity. Not + currently implemented. + type(port) Return a pointer to a string constant describing the specified port, or return NULL, in which case the string 'unknown' is @@ -307,6 +320,31 @@ hardware. Locking: none. Interrupts: caller dependent. + poll_init(port) + Called by kgdb to perform the minimal hardware initialization needed + to support poll_put_char() and poll_get_char(). Unlike ->startup() + this should not request interrupts. + + Locking: tty_mutex and tty_port->mutex taken. + Interrupts: n/a. + + poll_put_char(port,ch) + Called by kgdb to write a single character directly to the serial + port. It can and should block until there is space in the TX FIFO. + + Locking: none. + Interrupts: caller dependent. + This call must not sleep + + poll_get_char(port) + Called by kgdb to read a single character directly from the serial + port. If data is available, it should be returned; otherwise + the function should return NO_POLL_CHAR immediately. + + Locking: none. + Interrupts: caller dependent. + This call must not sleep + Other functions --------------- |