From e759d7c53b39a43fc908425bf9985b8b7d930550 Mon Sep 17 00:00:00 2001 From: Kevin Cernekee Date: Wed, 26 Dec 2012 20:43:42 -0800 Subject: [PATCH] tty: Update serial core API documentation Signed-off-by: Kevin Cernekee Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- Documentation/serial/driver | 39 +++++++++++++++++++++++++++++++++++++ include/linux/serial_core.h | 8 ++++---- 2 files changed, 43 insertions(+), 4 deletions(-) diff --git a/Documentation/serial/driver b/Documentation/serial/driver index a6ef8dc436f1..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. @@ -254,6 +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 @@ -306,6 +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 --------------- diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index ec5df74c4506..82aebc8ff77f 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -37,8 +37,8 @@ struct serial_struct; struct device; /* - * This structure describes all the operations that can be - * done on the physical hardware. + * This structure describes all the operations that can be done on the + * physical hardware. See Documentation/serial/driver for details. */ struct uart_ops { unsigned int (*tx_empty)(struct uart_port *); @@ -65,7 +65,7 @@ struct uart_ops { /* * Return a string describing the type of the port */ - const char *(*type)(struct uart_port *); + const char *(*type)(struct uart_port *); /* * Release IO and memory resources used by the port. @@ -83,7 +83,7 @@ struct uart_ops { int (*ioctl)(struct uart_port *, unsigned int, unsigned long); #ifdef CONFIG_CONSOLE_POLL int (*poll_init)(struct uart_port *); - void (*poll_put_char)(struct uart_port *, unsigned char); + void (*poll_put_char)(struct uart_port *, unsigned char); int (*poll_get_char)(struct uart_port *); #endif }; -- 2.20.1