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![Gustavo A. R. Silva](/assets/img/avatar_default.png)
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
811 lines
22 KiB
C
811 lines
22 KiB
C
/*
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* IEEE-1284 implementation for parport.
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*
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* Authors: Phil Blundell <philb@gnu.org>
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* Carsten Gross <carsten@sol.wohnheim.uni-ulm.de>
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* Jose Renau <renau@acm.org>
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* Tim Waugh <tim@cyberelk.demon.co.uk> (largely rewritten)
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*
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* This file is responsible for IEEE 1284 negotiation, and for handing
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* read/write requests to low-level drivers.
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*
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* Any part of this program may be used in documents licensed under
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* the GNU Free Documentation License, Version 1.1 or any later version
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* published by the Free Software Foundation.
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*
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* Various hacks, Fred Barnes <frmb2@ukc.ac.uk>, 04/2000
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*/
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#include <linux/module.h>
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#include <linux/threads.h>
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#include <linux/parport.h>
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#include <linux/delay.h>
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#include <linux/kernel.h>
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#include <linux/interrupt.h>
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#include <linux/timer.h>
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#include <linux/sched/signal.h>
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#undef DEBUG /* undef me for production */
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#ifdef CONFIG_LP_CONSOLE
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#undef DEBUG /* Don't want a garbled console */
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#endif
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#ifdef DEBUG
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#define DPRINTK(stuff...) printk (stuff)
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#else
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#define DPRINTK(stuff...)
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#endif
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/* Make parport_wait_peripheral wake up.
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* It will be useful to call this from an interrupt handler. */
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static void parport_ieee1284_wakeup (struct parport *port)
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{
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up (&port->physport->ieee1284.irq);
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}
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static void timeout_waiting_on_port (struct timer_list *t)
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{
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struct parport *port = from_timer(port, t, timer);
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parport_ieee1284_wakeup (port);
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}
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/**
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* parport_wait_event - wait for an event on a parallel port
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* @port: port to wait on
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* @timeout: time to wait (in jiffies)
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*
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* This function waits for up to @timeout jiffies for an
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* interrupt to occur on a parallel port. If the port timeout is
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* set to zero, it returns immediately.
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*
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* If an interrupt occurs before the timeout period elapses, this
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* function returns zero immediately. If it times out, it returns
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* one. An error code less than zero indicates an error (most
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* likely a pending signal), and the calling code should finish
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* what it's doing as soon as it can.
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*/
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int parport_wait_event (struct parport *port, signed long timeout)
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{
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int ret;
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if (!port->physport->cad->timeout)
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/* Zero timeout is special, and we can't down() the
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semaphore. */
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return 1;
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timer_setup(&port->timer, timeout_waiting_on_port, 0);
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mod_timer(&port->timer, jiffies + timeout);
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ret = down_interruptible (&port->physport->ieee1284.irq);
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if (!del_timer_sync(&port->timer) && !ret)
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/* Timed out. */
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ret = 1;
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return ret;
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}
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/**
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* parport_poll_peripheral - poll status lines
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* @port: port to watch
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* @mask: status lines to watch
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* @result: desired values of chosen status lines
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* @usec: timeout
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*
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* This function busy-waits until the masked status lines have
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* the desired values, or until the timeout period elapses. The
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* @mask and @result parameters are bitmasks, with the bits
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* defined by the constants in parport.h: %PARPORT_STATUS_BUSY,
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* and so on.
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*
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* This function does not call schedule(); instead it busy-waits
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* using udelay(). It currently has a resolution of 5usec.
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*
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* If the status lines take on the desired values before the
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* timeout period elapses, parport_poll_peripheral() returns zero
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* immediately. A return value greater than zero indicates
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* a timeout. An error code (less than zero) indicates an error,
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* most likely a signal that arrived, and the caller should
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* finish what it is doing as soon as possible.
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*/
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int parport_poll_peripheral(struct parport *port,
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unsigned char mask,
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unsigned char result,
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int usec)
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{
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/* Zero return code is success, >0 is timeout. */
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int count = usec / 5 + 2;
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int i;
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unsigned char status;
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for (i = 0; i < count; i++) {
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status = parport_read_status (port);
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if ((status & mask) == result)
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return 0;
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if (signal_pending (current))
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return -EINTR;
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if (need_resched())
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break;
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if (i >= 2)
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udelay (5);
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}
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return 1;
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}
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/**
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* parport_wait_peripheral - wait for status lines to change in 35ms
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* @port: port to watch
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* @mask: status lines to watch
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* @result: desired values of chosen status lines
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*
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* This function waits until the masked status lines have the
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* desired values, or until 35ms have elapsed (see IEEE 1284-1994
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* page 24 to 25 for why this value in particular is hardcoded).
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* The @mask and @result parameters are bitmasks, with the bits
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* defined by the constants in parport.h: %PARPORT_STATUS_BUSY,
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* and so on.
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*
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* The port is polled quickly to start off with, in anticipation
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* of a fast response from the peripheral. This fast polling
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* time is configurable (using /proc), and defaults to 500usec.
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* If the timeout for this port (see parport_set_timeout()) is
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* zero, the fast polling time is 35ms, and this function does
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* not call schedule().
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*
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* If the timeout for this port is non-zero, after the fast
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* polling fails it uses parport_wait_event() to wait for up to
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* 10ms, waking up if an interrupt occurs.
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*/
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int parport_wait_peripheral(struct parport *port,
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unsigned char mask,
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unsigned char result)
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{
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int ret;
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int usec;
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unsigned long deadline;
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unsigned char status;
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usec = port->physport->spintime; /* usecs of fast polling */
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if (!port->physport->cad->timeout)
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/* A zero timeout is "special": busy wait for the
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entire 35ms. */
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usec = 35000;
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/* Fast polling.
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*
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* This should be adjustable.
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* How about making a note (in the device structure) of how long
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* it takes, so we know for next time?
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*/
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ret = parport_poll_peripheral (port, mask, result, usec);
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if (ret != 1)
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return ret;
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if (!port->physport->cad->timeout)
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/* We may be in an interrupt handler, so we can't poll
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* slowly anyway. */
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return 1;
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/* 40ms of slow polling. */
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deadline = jiffies + msecs_to_jiffies(40);
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while (time_before (jiffies, deadline)) {
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if (signal_pending (current))
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return -EINTR;
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/* Wait for 10ms (or until an interrupt occurs if
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* the handler is set) */
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if ((ret = parport_wait_event (port, msecs_to_jiffies(10))) < 0)
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return ret;
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status = parport_read_status (port);
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if ((status & mask) == result)
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return 0;
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if (!ret) {
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/* parport_wait_event didn't time out, but the
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* peripheral wasn't actually ready either.
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* Wait for another 10ms. */
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schedule_timeout_interruptible(msecs_to_jiffies(10));
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}
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}
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return 1;
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}
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#ifdef CONFIG_PARPORT_1284
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/* Terminate a negotiated mode. */
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static void parport_ieee1284_terminate (struct parport *port)
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{
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int r;
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port = port->physport;
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/* EPP terminates differently. */
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switch (port->ieee1284.mode) {
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case IEEE1284_MODE_EPP:
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case IEEE1284_MODE_EPPSL:
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case IEEE1284_MODE_EPPSWE:
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/* Terminate from EPP mode. */
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/* Event 68: Set nInit low */
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parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
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udelay (50);
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/* Event 69: Set nInit high, nSelectIn low */
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parport_frob_control (port,
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PARPORT_CONTROL_SELECT
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| PARPORT_CONTROL_INIT,
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PARPORT_CONTROL_SELECT
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| PARPORT_CONTROL_INIT);
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break;
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case IEEE1284_MODE_ECP:
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case IEEE1284_MODE_ECPRLE:
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case IEEE1284_MODE_ECPSWE:
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/* In ECP we can only terminate from fwd idle phase. */
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if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE) {
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/* Event 47: Set nInit high */
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parport_frob_control (port,
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PARPORT_CONTROL_INIT
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| PARPORT_CONTROL_AUTOFD,
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PARPORT_CONTROL_INIT
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| PARPORT_CONTROL_AUTOFD);
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/* Event 49: PError goes high */
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r = parport_wait_peripheral (port,
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PARPORT_STATUS_PAPEROUT,
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PARPORT_STATUS_PAPEROUT);
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if (r)
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DPRINTK (KERN_INFO "%s: Timeout at event 49\n",
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port->name);
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parport_data_forward (port);
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DPRINTK (KERN_DEBUG "%s: ECP direction: forward\n",
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port->name);
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port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
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}
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/* fall through */
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default:
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/* Terminate from all other modes. */
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/* Event 22: Set nSelectIn low, nAutoFd high */
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parport_frob_control (port,
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PARPORT_CONTROL_SELECT
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| PARPORT_CONTROL_AUTOFD,
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PARPORT_CONTROL_SELECT);
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/* Event 24: nAck goes low */
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r = parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0);
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if (r)
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DPRINTK (KERN_INFO "%s: Timeout at event 24\n",
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port->name);
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/* Event 25: Set nAutoFd low */
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parport_frob_control (port,
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PARPORT_CONTROL_AUTOFD,
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PARPORT_CONTROL_AUTOFD);
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/* Event 27: nAck goes high */
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r = parport_wait_peripheral (port,
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PARPORT_STATUS_ACK,
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PARPORT_STATUS_ACK);
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if (r)
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DPRINTK (KERN_INFO "%s: Timeout at event 27\n",
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port->name);
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/* Event 29: Set nAutoFd high */
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parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
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}
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port->ieee1284.mode = IEEE1284_MODE_COMPAT;
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port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
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DPRINTK (KERN_DEBUG "%s: In compatibility (forward idle) mode\n",
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port->name);
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}
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#endif /* IEEE1284 support */
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/**
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* parport_negotiate - negotiate an IEEE 1284 mode
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* @port: port to use
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* @mode: mode to negotiate to
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*
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* Use this to negotiate to a particular IEEE 1284 transfer mode.
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* The @mode parameter should be one of the constants in
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* parport.h starting %IEEE1284_MODE_xxx.
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*
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* The return value is 0 if the peripheral has accepted the
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* negotiation to the mode specified, -1 if the peripheral is not
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* IEEE 1284 compliant (or not present), or 1 if the peripheral
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* has rejected the negotiation.
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*/
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int parport_negotiate (struct parport *port, int mode)
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{
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#ifndef CONFIG_PARPORT_1284
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if (mode == IEEE1284_MODE_COMPAT)
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return 0;
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printk (KERN_ERR "parport: IEEE1284 not supported in this kernel\n");
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return -1;
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#else
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int m = mode & ~IEEE1284_ADDR;
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int r;
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unsigned char xflag;
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port = port->physport;
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/* Is there anything to do? */
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if (port->ieee1284.mode == mode)
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return 0;
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/* Is the difference just an address-or-not bit? */
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if ((port->ieee1284.mode & ~IEEE1284_ADDR) == (mode & ~IEEE1284_ADDR)){
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port->ieee1284.mode = mode;
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return 0;
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}
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/* Go to compatibility forward idle mode */
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if (port->ieee1284.mode != IEEE1284_MODE_COMPAT)
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parport_ieee1284_terminate (port);
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if (mode == IEEE1284_MODE_COMPAT)
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/* Compatibility mode: no negotiation. */
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return 0;
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switch (mode) {
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case IEEE1284_MODE_ECPSWE:
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m = IEEE1284_MODE_ECP;
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break;
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case IEEE1284_MODE_EPPSL:
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case IEEE1284_MODE_EPPSWE:
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m = IEEE1284_MODE_EPP;
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break;
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case IEEE1284_MODE_BECP:
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return -ENOSYS; /* FIXME (implement BECP) */
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}
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if (mode & IEEE1284_EXT_LINK)
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m = 1<<7; /* request extensibility link */
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port->ieee1284.phase = IEEE1284_PH_NEGOTIATION;
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/* Start off with nStrobe and nAutoFd high, and nSelectIn low */
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parport_frob_control (port,
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PARPORT_CONTROL_STROBE
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| PARPORT_CONTROL_AUTOFD
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| PARPORT_CONTROL_SELECT,
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PARPORT_CONTROL_SELECT);
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udelay(1);
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/* Event 0: Set data */
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parport_data_forward (port);
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parport_write_data (port, m);
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udelay (400); /* Shouldn't need to wait this long. */
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/* Event 1: Set nSelectIn high, nAutoFd low */
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parport_frob_control (port,
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PARPORT_CONTROL_SELECT
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| PARPORT_CONTROL_AUTOFD,
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PARPORT_CONTROL_AUTOFD);
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/* Event 2: PError, Select, nFault go high, nAck goes low */
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if (parport_wait_peripheral (port,
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PARPORT_STATUS_ERROR
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| PARPORT_STATUS_SELECT
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| PARPORT_STATUS_PAPEROUT
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| PARPORT_STATUS_ACK,
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PARPORT_STATUS_ERROR
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| PARPORT_STATUS_SELECT
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| PARPORT_STATUS_PAPEROUT)) {
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/* Timeout */
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parport_frob_control (port,
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PARPORT_CONTROL_SELECT
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| PARPORT_CONTROL_AUTOFD,
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PARPORT_CONTROL_SELECT);
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DPRINTK (KERN_DEBUG
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"%s: Peripheral not IEEE1284 compliant (0x%02X)\n",
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port->name, parport_read_status (port));
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port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
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return -1; /* Not IEEE1284 compliant */
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}
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/* Event 3: Set nStrobe low */
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parport_frob_control (port,
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PARPORT_CONTROL_STROBE,
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PARPORT_CONTROL_STROBE);
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/* Event 4: Set nStrobe and nAutoFd high */
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udelay (5);
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parport_frob_control (port,
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PARPORT_CONTROL_STROBE
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| PARPORT_CONTROL_AUTOFD,
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0);
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/* Event 6: nAck goes high */
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if (parport_wait_peripheral (port,
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PARPORT_STATUS_ACK,
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PARPORT_STATUS_ACK)) {
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/* This shouldn't really happen with a compliant device. */
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DPRINTK (KERN_DEBUG
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"%s: Mode 0x%02x not supported? (0x%02x)\n",
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port->name, mode, port->ops->read_status (port));
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parport_ieee1284_terminate (port);
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return 1;
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}
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xflag = parport_read_status (port) & PARPORT_STATUS_SELECT;
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/* xflag should be high for all modes other than nibble (0). */
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if (mode && !xflag) {
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/* Mode not supported. */
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DPRINTK (KERN_DEBUG "%s: Mode 0x%02x rejected by peripheral\n",
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port->name, mode);
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parport_ieee1284_terminate (port);
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return 1;
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}
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|
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/* More to do if we've requested extensibility link. */
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if (mode & IEEE1284_EXT_LINK) {
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m = mode & 0x7f;
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udelay (1);
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parport_write_data (port, m);
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udelay (1);
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|
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/* Event 51: Set nStrobe low */
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parport_frob_control (port,
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PARPORT_CONTROL_STROBE,
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PARPORT_CONTROL_STROBE);
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|
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/* Event 52: nAck goes low */
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if (parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0)) {
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/* This peripheral is _very_ slow. */
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DPRINTK (KERN_DEBUG
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"%s: Event 52 didn't happen\n",
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port->name);
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parport_ieee1284_terminate (port);
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return 1;
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}
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|
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/* Event 53: Set nStrobe high */
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parport_frob_control (port,
|
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PARPORT_CONTROL_STROBE,
|
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0);
|
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|
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/* Event 55: nAck goes high */
|
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if (parport_wait_peripheral (port,
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PARPORT_STATUS_ACK,
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PARPORT_STATUS_ACK)) {
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/* This shouldn't really happen with a compliant
|
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* device. */
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DPRINTK (KERN_DEBUG
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"%s: Mode 0x%02x not supported? (0x%02x)\n",
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port->name, mode,
|
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port->ops->read_status (port));
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parport_ieee1284_terminate (port);
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return 1;
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}
|
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|
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/* Event 54: Peripheral sets XFlag to reflect support */
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xflag = parport_read_status (port) & PARPORT_STATUS_SELECT;
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|
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/* xflag should be high. */
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if (!xflag) {
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/* Extended mode not supported. */
|
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DPRINTK (KERN_DEBUG "%s: Extended mode 0x%02x not "
|
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"supported\n", port->name, mode);
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parport_ieee1284_terminate (port);
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return 1;
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}
|
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|
|
/* Any further setup is left to the caller. */
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|
}
|
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|
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/* Mode is supported */
|
|
DPRINTK (KERN_DEBUG "%s: In mode 0x%02x\n", port->name, mode);
|
|
port->ieee1284.mode = mode;
|
|
|
|
/* But ECP is special */
|
|
if (!(mode & IEEE1284_EXT_LINK) && (m & IEEE1284_MODE_ECP)) {
|
|
port->ieee1284.phase = IEEE1284_PH_ECP_SETUP;
|
|
|
|
/* Event 30: Set nAutoFd low */
|
|
parport_frob_control (port,
|
|
PARPORT_CONTROL_AUTOFD,
|
|
PARPORT_CONTROL_AUTOFD);
|
|
|
|
/* Event 31: PError goes high. */
|
|
r = parport_wait_peripheral (port,
|
|
PARPORT_STATUS_PAPEROUT,
|
|
PARPORT_STATUS_PAPEROUT);
|
|
if (r) {
|
|
DPRINTK (KERN_INFO "%s: Timeout at event 31\n",
|
|
port->name);
|
|
}
|
|
|
|
port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
|
|
DPRINTK (KERN_DEBUG "%s: ECP direction: forward\n",
|
|
port->name);
|
|
} else switch (mode) {
|
|
case IEEE1284_MODE_NIBBLE:
|
|
case IEEE1284_MODE_BYTE:
|
|
port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
|
|
break;
|
|
default:
|
|
port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
|
|
}
|
|
|
|
|
|
return 0;
|
|
#endif /* IEEE1284 support */
|
|
}
|
|
|
|
/* Acknowledge that the peripheral has data available.
|
|
* Events 18-20, in order to get from Reverse Idle phase
|
|
* to Host Busy Data Available.
|
|
* This will most likely be called from an interrupt.
|
|
* Returns zero if data was available.
|
|
*/
|
|
#ifdef CONFIG_PARPORT_1284
|
|
static int parport_ieee1284_ack_data_avail (struct parport *port)
|
|
{
|
|
if (parport_read_status (port) & PARPORT_STATUS_ERROR)
|
|
/* Event 18 didn't happen. */
|
|
return -1;
|
|
|
|
/* Event 20: nAutoFd goes high. */
|
|
port->ops->frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
|
|
port->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
|
|
return 0;
|
|
}
|
|
#endif /* IEEE1284 support */
|
|
|
|
/* Handle an interrupt. */
|
|
void parport_ieee1284_interrupt (void *handle)
|
|
{
|
|
struct parport *port = handle;
|
|
parport_ieee1284_wakeup (port);
|
|
|
|
#ifdef CONFIG_PARPORT_1284
|
|
if (port->ieee1284.phase == IEEE1284_PH_REV_IDLE) {
|
|
/* An interrupt in this phase means that data
|
|
* is now available. */
|
|
DPRINTK (KERN_DEBUG "%s: Data available\n", port->name);
|
|
parport_ieee1284_ack_data_avail (port);
|
|
}
|
|
#endif /* IEEE1284 support */
|
|
}
|
|
|
|
/**
|
|
* parport_write - write a block of data to a parallel port
|
|
* @port: port to write to
|
|
* @buffer: data buffer (in kernel space)
|
|
* @len: number of bytes of data to transfer
|
|
*
|
|
* This will write up to @len bytes of @buffer to the port
|
|
* specified, using the IEEE 1284 transfer mode most recently
|
|
* negotiated to (using parport_negotiate()), as long as that
|
|
* mode supports forward transfers (host to peripheral).
|
|
*
|
|
* It is the caller's responsibility to ensure that the first
|
|
* @len bytes of @buffer are valid.
|
|
*
|
|
* This function returns the number of bytes transferred (if zero
|
|
* or positive), or else an error code.
|
|
*/
|
|
|
|
ssize_t parport_write (struct parport *port, const void *buffer, size_t len)
|
|
{
|
|
#ifndef CONFIG_PARPORT_1284
|
|
return port->ops->compat_write_data (port, buffer, len, 0);
|
|
#else
|
|
ssize_t retval;
|
|
int mode = port->ieee1284.mode;
|
|
int addr = mode & IEEE1284_ADDR;
|
|
size_t (*fn) (struct parport *, const void *, size_t, int);
|
|
|
|
/* Ignore the device-ID-request bit and the address bit. */
|
|
mode &= ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
|
|
|
|
/* Use the mode we're in. */
|
|
switch (mode) {
|
|
case IEEE1284_MODE_NIBBLE:
|
|
case IEEE1284_MODE_BYTE:
|
|
parport_negotiate (port, IEEE1284_MODE_COMPAT);
|
|
/* fall through */
|
|
case IEEE1284_MODE_COMPAT:
|
|
DPRINTK (KERN_DEBUG "%s: Using compatibility mode\n",
|
|
port->name);
|
|
fn = port->ops->compat_write_data;
|
|
break;
|
|
|
|
case IEEE1284_MODE_EPP:
|
|
DPRINTK (KERN_DEBUG "%s: Using EPP mode\n", port->name);
|
|
if (addr) {
|
|
fn = port->ops->epp_write_addr;
|
|
} else {
|
|
fn = port->ops->epp_write_data;
|
|
}
|
|
break;
|
|
case IEEE1284_MODE_EPPSWE:
|
|
DPRINTK (KERN_DEBUG "%s: Using software-emulated EPP mode\n",
|
|
port->name);
|
|
if (addr) {
|
|
fn = parport_ieee1284_epp_write_addr;
|
|
} else {
|
|
fn = parport_ieee1284_epp_write_data;
|
|
}
|
|
break;
|
|
case IEEE1284_MODE_ECP:
|
|
case IEEE1284_MODE_ECPRLE:
|
|
DPRINTK (KERN_DEBUG "%s: Using ECP mode\n", port->name);
|
|
if (addr) {
|
|
fn = port->ops->ecp_write_addr;
|
|
} else {
|
|
fn = port->ops->ecp_write_data;
|
|
}
|
|
break;
|
|
|
|
case IEEE1284_MODE_ECPSWE:
|
|
DPRINTK (KERN_DEBUG "%s: Using software-emulated ECP mode\n",
|
|
port->name);
|
|
/* The caller has specified that it must be emulated,
|
|
* even if we have ECP hardware! */
|
|
if (addr) {
|
|
fn = parport_ieee1284_ecp_write_addr;
|
|
} else {
|
|
fn = parport_ieee1284_ecp_write_data;
|
|
}
|
|
break;
|
|
|
|
default:
|
|
DPRINTK (KERN_DEBUG "%s: Unknown mode 0x%02x\n", port->name,
|
|
port->ieee1284.mode);
|
|
return -ENOSYS;
|
|
}
|
|
|
|
retval = (*fn) (port, buffer, len, 0);
|
|
DPRINTK (KERN_DEBUG "%s: wrote %d/%d bytes\n", port->name, retval, len);
|
|
return retval;
|
|
#endif /* IEEE1284 support */
|
|
}
|
|
|
|
/**
|
|
* parport_read - read a block of data from a parallel port
|
|
* @port: port to read from
|
|
* @buffer: data buffer (in kernel space)
|
|
* @len: number of bytes of data to transfer
|
|
*
|
|
* This will read up to @len bytes of @buffer to the port
|
|
* specified, using the IEEE 1284 transfer mode most recently
|
|
* negotiated to (using parport_negotiate()), as long as that
|
|
* mode supports reverse transfers (peripheral to host).
|
|
*
|
|
* It is the caller's responsibility to ensure that the first
|
|
* @len bytes of @buffer are available to write to.
|
|
*
|
|
* This function returns the number of bytes transferred (if zero
|
|
* or positive), or else an error code.
|
|
*/
|
|
|
|
ssize_t parport_read (struct parport *port, void *buffer, size_t len)
|
|
{
|
|
#ifndef CONFIG_PARPORT_1284
|
|
printk (KERN_ERR "parport: IEEE1284 not supported in this kernel\n");
|
|
return -ENODEV;
|
|
#else
|
|
int mode = port->physport->ieee1284.mode;
|
|
int addr = mode & IEEE1284_ADDR;
|
|
size_t (*fn) (struct parport *, void *, size_t, int);
|
|
|
|
/* Ignore the device-ID-request bit and the address bit. */
|
|
mode &= ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
|
|
|
|
/* Use the mode we're in. */
|
|
switch (mode) {
|
|
case IEEE1284_MODE_COMPAT:
|
|
/* if we can tri-state use BYTE mode instead of NIBBLE mode,
|
|
* if that fails, revert to NIBBLE mode -- ought to store somewhere
|
|
* the device's ability to do BYTE mode reverse transfers, so we don't
|
|
* end up needlessly calling negotiate(BYTE) repeately.. (fb)
|
|
*/
|
|
if ((port->physport->modes & PARPORT_MODE_TRISTATE) &&
|
|
!parport_negotiate (port, IEEE1284_MODE_BYTE)) {
|
|
/* got into BYTE mode OK */
|
|
DPRINTK (KERN_DEBUG "%s: Using byte mode\n", port->name);
|
|
fn = port->ops->byte_read_data;
|
|
break;
|
|
}
|
|
if (parport_negotiate (port, IEEE1284_MODE_NIBBLE)) {
|
|
return -EIO;
|
|
}
|
|
/* fall through to NIBBLE */
|
|
case IEEE1284_MODE_NIBBLE:
|
|
DPRINTK (KERN_DEBUG "%s: Using nibble mode\n", port->name);
|
|
fn = port->ops->nibble_read_data;
|
|
break;
|
|
|
|
case IEEE1284_MODE_BYTE:
|
|
DPRINTK (KERN_DEBUG "%s: Using byte mode\n", port->name);
|
|
fn = port->ops->byte_read_data;
|
|
break;
|
|
|
|
case IEEE1284_MODE_EPP:
|
|
DPRINTK (KERN_DEBUG "%s: Using EPP mode\n", port->name);
|
|
if (addr) {
|
|
fn = port->ops->epp_read_addr;
|
|
} else {
|
|
fn = port->ops->epp_read_data;
|
|
}
|
|
break;
|
|
case IEEE1284_MODE_EPPSWE:
|
|
DPRINTK (KERN_DEBUG "%s: Using software-emulated EPP mode\n",
|
|
port->name);
|
|
if (addr) {
|
|
fn = parport_ieee1284_epp_read_addr;
|
|
} else {
|
|
fn = parport_ieee1284_epp_read_data;
|
|
}
|
|
break;
|
|
case IEEE1284_MODE_ECP:
|
|
case IEEE1284_MODE_ECPRLE:
|
|
DPRINTK (KERN_DEBUG "%s: Using ECP mode\n", port->name);
|
|
fn = port->ops->ecp_read_data;
|
|
break;
|
|
|
|
case IEEE1284_MODE_ECPSWE:
|
|
DPRINTK (KERN_DEBUG "%s: Using software-emulated ECP mode\n",
|
|
port->name);
|
|
fn = parport_ieee1284_ecp_read_data;
|
|
break;
|
|
|
|
default:
|
|
DPRINTK (KERN_DEBUG "%s: Unknown mode 0x%02x\n", port->name,
|
|
port->physport->ieee1284.mode);
|
|
return -ENOSYS;
|
|
}
|
|
|
|
return (*fn) (port, buffer, len, 0);
|
|
#endif /* IEEE1284 support */
|
|
}
|
|
|
|
/**
|
|
* parport_set_timeout - set the inactivity timeout for a device
|
|
* @dev: device on a port
|
|
* @inactivity: inactivity timeout (in jiffies)
|
|
*
|
|
* This sets the inactivity timeout for a particular device on a
|
|
* port. This affects functions like parport_wait_peripheral().
|
|
* The special value 0 means not to call schedule() while dealing
|
|
* with this device.
|
|
*
|
|
* The return value is the previous inactivity timeout.
|
|
*
|
|
* Any callers of parport_wait_event() for this device are woken
|
|
* up.
|
|
*/
|
|
|
|
long parport_set_timeout (struct pardevice *dev, long inactivity)
|
|
{
|
|
long int old = dev->timeout;
|
|
|
|
dev->timeout = inactivity;
|
|
|
|
if (dev->port->physport->cad == dev)
|
|
parport_ieee1284_wakeup (dev->port);
|
|
|
|
return old;
|
|
}
|
|
|
|
/* Exported symbols for modules. */
|
|
|
|
EXPORT_SYMBOL(parport_negotiate);
|
|
EXPORT_SYMBOL(parport_write);
|
|
EXPORT_SYMBOL(parport_read);
|
|
EXPORT_SYMBOL(parport_wait_peripheral);
|
|
EXPORT_SYMBOL(parport_wait_event);
|
|
EXPORT_SYMBOL(parport_set_timeout);
|
|
EXPORT_SYMBOL(parport_ieee1284_interrupt);
|