Merge branch 'atmel'

[linux-2.6-omap-h63xx.git] / Documentation / serial / driver

diff --git a/Documentation/serial/driver b/Documentation/serial/driver
index 87856d3cfb67fbcd16baf475c262c909f862cbb1..42ef9970bc86b1ad762a5928942f63085be0019d 100644 (file)
--- a/Documentation/serial/driver
+++ b/Documentation/serial/driver
@@ -116,12 +116,15 @@ hardware.
        line becoming inactive or the tty layer indicating we want
        to stop transmission due to an XOFF character.
 
        line becoming inactive or the tty layer indicating we want
        to stop transmission due to an XOFF character.
 

+       The driver should stop transmitting characters as soon as
+       possible.
+

        Locking: port->lock taken.
        Interrupts: locally disabled.
        This call must not sleep
 
   start_tx(port)
        Locking: port->lock taken.
        Interrupts: locally disabled.
        This call must not sleep
 
   start_tx(port)

-       start transmitting characters.
+       Start transmitting characters.

 
        Locking: port->lock taken.
        Interrupts: locally disabled.
 
        Locking: port->lock taken.
        Interrupts: locally disabled.


@@ -281,26 +284,31 @@ hardware.
 Other functions
 ---------------
 
 Other functions
 ---------------
 

-uart_update_timeout(port,cflag,quot)
+uart_update_timeout(port,cflag,baud)

        Update the FIFO drain timeout, port->timeout, according to the
        Update the FIFO drain timeout, port->timeout, according to the

-       number of bits, parity, stop bits and quotient.
+       number of bits, parity, stop bits and baud rate.

 
        Locking: caller is expected to take port->lock
        Interrupts: n/a
 
 
        Locking: caller is expected to take port->lock
        Interrupts: n/a
 

-uart_get_baud_rate(port,termios)
+uart_get_baud_rate(port,termios,old,min,max)

        Return the numeric baud rate for the specified termios, taking
        account of the special 38400 baud "kludge".  The B0 baud rate
        is mapped to 9600 baud.
 
        Return the numeric baud rate for the specified termios, taking
        account of the special 38400 baud "kludge".  The B0 baud rate
        is mapped to 9600 baud.
 

+       If the baud rate is not within min..max, then if old is non-NULL,
+       the original baud rate will be tried.  If that exceeds the
+       min..max constraint, 9600 baud will be returned.  termios will
+       be updated to the baud rate in use.
+
+       Note: min..max must always allow 9600 baud to be selected.
+

        Locking: caller dependent.
        Interrupts: n/a
 
        Locking: caller dependent.
        Interrupts: n/a
 

-uart_get_divisor(port,termios,oldtermios)
-       Return the divsor (baud_base / baud) for the selected baud rate
-       specified by termios.  If the baud rate is out of range, try
-       the original baud rate specified by oldtermios (if non-NULL).
-       If that fails, try 9600 baud.
+uart_get_divisor(port,baud)
+       Return the divsor (baud_base / baud) for the specified baud
+       rate, appropriately rounded.

 
        If 38400 baud and custom divisor is selected, return the
        custom divisor instead.
 
        If 38400 baud and custom divisor is selected, return the
        custom divisor instead.


@@ -308,6 +316,46 @@ uart_get_divisor(port,termios,oldtermios)
        Locking: caller dependent.
        Interrupts: n/a
 
        Locking: caller dependent.
        Interrupts: n/a
 

+uart_match_port(port1,port2)
+       This utility function can be used to determine whether two
+       uart_port structures describe the same port.
+
+       Locking: n/a
+       Interrupts: n/a
+
+uart_write_wakeup(port)
+       A driver is expected to call this function when the number of
+       characters in the transmit buffer have dropped below a threshold.
+
+       Locking: port->lock should be held.
+       Interrupts: n/a
+
+uart_register_driver(drv)
+       Register a uart driver with the core driver.  We in turn register
+       with the tty layer, and initialise the core driver per-port state.
+
+       drv->port should be NULL, and the per-port structures should be
+       registered using uart_add_one_port after this call has succeeded.
+
+       Locking: none
+       Interrupts: enabled
+
+uart_unregister_driver()
+       Remove all references to a driver from the core driver.  The low
+       level driver must have removed all its ports via the
+       uart_remove_one_port() if it registered them with uart_add_one_port().
+
+       Locking: none
+       Interrupts: enabled
+
+uart_suspend_port()
+
+uart_resume_port()
+
+uart_add_one_port()
+
+uart_remove_one_port()
+

 Other notes
 -----------
 
 Other notes
 -----------