Current File : //usr/src/linux-headers-5.15.0-125-generic/include/linux/lp.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
* usr/include/linux/lp.h c.1991-1992 James Wiegand
* many modifications copyright (C) 1992 Michael K. Johnson
* Interrupt support added 1993 Nigel Gamble
* Removed 8255 status defines from inside __KERNEL__ Marcelo Tosatti
*/
#ifndef _LINUX_LP_H
#define _LINUX_LP_H
#include <linux/wait.h>
#include <linux/mutex.h>
#include <uapi/linux/lp.h>
/* Magic numbers for defining port-device mappings */
#define LP_PARPORT_UNSPEC -4
#define LP_PARPORT_AUTO -3
#define LP_PARPORT_OFF -2
#define LP_PARPORT_NONE -1
#define LP_F(minor) lp_table[(minor)].flags /* flags for busy, etc. */
#define LP_CHAR(minor) lp_table[(minor)].chars /* busy timeout */
#define LP_TIME(minor) lp_table[(minor)].time /* wait time */
#define LP_WAIT(minor) lp_table[(minor)].wait /* strobe wait */
#define LP_IRQ(minor) lp_table[(minor)].dev->port->irq /* interrupt # */
/* PARPORT_IRQ_NONE means polled */
#ifdef LP_STATS
#define LP_STAT(minor) lp_table[(minor)].stats /* statistics area */
#endif
#define LP_BUFFER_SIZE PAGE_SIZE
#define LP_BASE(x) lp_table[(x)].dev->port->base
#ifdef LP_STATS
struct lp_stats {
unsigned long chars;
unsigned long sleeps;
unsigned int maxrun;
unsigned int maxwait;
unsigned int meanwait;
unsigned int mdev;
};
#endif
struct lp_struct {
struct pardevice *dev;
unsigned long flags;
unsigned int chars;
unsigned int time;
unsigned int wait;
char *lp_buffer;
#ifdef LP_STATS
unsigned int lastcall;
unsigned int runchars;
struct lp_stats stats;
#endif
wait_queue_head_t waitq;
unsigned int last_error;
struct mutex port_mutex;
wait_queue_head_t dataq;
long timeout;
unsigned int best_mode;
unsigned int current_mode;
unsigned long bits;
};
/*
* The following constants describe the various signals of the printer port
* hardware. Note that the hardware inverts some signals and that some
* signals are active low. An example is LP_STROBE, which must be programmed
* with 1 for being active and 0 for being inactive, because the strobe signal
* gets inverted, but it is also active low.
*/
/*
* defines for 8255 control port
* base + 2
* accessed with LP_C(minor)
*/
#define LP_PINTEN 0x10 /* high to read data in or-ed with data out */
#define LP_PSELECP 0x08 /* inverted output, active low */
#define LP_PINITP 0x04 /* unchanged output, active low */
#define LP_PAUTOLF 0x02 /* inverted output, active low */
#define LP_PSTROBE 0x01 /* short high output on raising edge */
/*
* the value written to ports to test existence. PC-style ports will
* return the value written. AT-style ports will return 0. so why not
* make them the same ?
*/
#define LP_DUMMY 0x00
/*
* This is the port delay time, in microseconds.
* It is used only in the lp_init() and lp_reset() routine.
*/
#define LP_DELAY 50
#endif
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