xref: /openbmc/linux/include/linux/lp.h (revision b2441318)
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
36 struct 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 
46 struct 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