LXR linux/include/linux/lp.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * usr/include/linux/lp.h c.1991-1992 James Wiegand
   4 * many modifications copyright (C) 1992 Michael K. Johnson
   5 * Interrupt support added 1993 Nigel Gamble
   6 * Removed 8255 status defines from inside __KERNEL__ Marcelo Tosatti 
   7 */
   8#ifndef _LINUX_LP_H
   9#define _LINUX_LP_H
  10
  11
  12#include <linux/wait.h>
  13#include <linux/mutex.h>
  14#include <uapi/linux/lp.h>
  15
  16/* Magic numbers for defining port-device mappings */
  17#define LP_PARPORT_UNSPEC -4
  18#define LP_PARPORT_AUTO -3
  19#define LP_PARPORT_OFF -2
  20#define LP_PARPORT_NONE -1
  21
  22#define LP_F(minor)     lp_table[(minor)].flags         /* flags for busy, etc. */
  23#define LP_CHAR(minor)  lp_table[(minor)].chars         /* busy timeout */
  24#define LP_TIME(minor)  lp_table[(minor)].time          /* wait time */
  25#define LP_WAIT(minor)  lp_table[(minor)].wait          /* strobe wait */
  26#define LP_IRQ(minor)   lp_table[(minor)].dev->port->irq /* interrupt # */
  27                                        /* PARPORT_IRQ_NONE means polled */
  28#ifdef LP_STATS
  29#define LP_STAT(minor)  lp_table[(minor)].stats         /* statistics area */
  30#endif
  31#define LP_BUFFER_SIZE PAGE_SIZE
  32
  33#define LP_BASE(x)      lp_table[(x)].dev->port->base
  34
  35#ifdef LP_STATS
  36struct lp_stats {
  37        unsigned long chars;
  38        unsigned long sleeps;
  39        unsigned int maxrun;
  40        unsigned int maxwait;
  41        unsigned int meanwait;
  42        unsigned int mdev;
  43};
  44#endif
  45
  46struct lp_struct {
  47        struct pardevice *dev;
  48        unsigned long flags;
  49        unsigned int chars;
  50        unsigned int time;
  51        unsigned int wait;
  52        char *lp_buffer;
  53#ifdef LP_STATS
  54        unsigned int lastcall;
  55        unsigned int runchars;
  56        struct lp_stats stats;
  57#endif
  58        wait_queue_head_t waitq;
  59        unsigned int last_error;
  60        struct mutex port_mutex;
  61        wait_queue_head_t dataq;
  62        long timeout;
  63        unsigned int best_mode;
  64        unsigned int current_mode;
  65        unsigned long bits;
  66};
  67
  68/*
  69 * The following constants describe the various signals of the printer port
  70 * hardware.  Note that the hardware inverts some signals and that some
  71 * signals are active low.  An example is LP_STROBE, which must be programmed
  72 * with 1 for being active and 0 for being inactive, because the strobe signal
  73 * gets inverted, but it is also active low.
  74 */
  75
  76
  77/* 
  78 * defines for 8255 control port
  79 * base + 2 
  80 * accessed with LP_C(minor)
  81 */
  82#define LP_PINTEN       0x10  /* high to read data in or-ed with data out */
  83#define LP_PSELECP      0x08  /* inverted output, active low */
  84#define LP_PINITP       0x04  /* unchanged output, active low */
  85#define LP_PAUTOLF      0x02  /* inverted output, active low */
  86#define LP_PSTROBE      0x01  /* short high output on raising edge */
  87
  88/* 
  89 * the value written to ports to test existence. PC-style ports will 
  90 * return the value written. AT-style ports will return 0. so why not
  91 * make them the same ? 
  92 */
  93#define LP_DUMMY        0x00
  94
  95/*
  96 * This is the port delay time, in microseconds.
  97 * It is used only in the lp_init() and lp_reset() routine.
  98 */
  99#define LP_DELAY        50
 100
 101#endif
 102