comedi_8255.h

 1/* SPDX-License-Identifier: GPL-2.0+ */
 2/*
 3 * comedi_8255.h
 4 * Generic 8255 digital I/O subdevice support
 5 *
 6 * COMEDI - Linux Control and Measurement Device Interface
 7 * Copyright (C) 1998 David A. Schleef <ds@schleef.org>
 8 */
 9
10#ifndef _COMEDI_8255_H
11#define _COMEDI_8255_H
12
13#include <linux/errno.h>
14
15#define I8255_SIZE		0x04
16
17#define I8255_DATA_A_REG	0x00
18#define I8255_DATA_B_REG	0x01
19#define I8255_DATA_C_REG	0x02
20#define I8255_CTRL_REG		0x03
21#define I8255_CTRL_C_LO_IO	BIT(0)
22#define I8255_CTRL_B_IO		BIT(1)
23#define I8255_CTRL_B_MODE	BIT(2)
24#define I8255_CTRL_C_HI_IO	BIT(3)
25#define I8255_CTRL_A_IO		BIT(4)
26#define I8255_CTRL_A_MODE(x)	((x) << 5)
27#define I8255_CTRL_CW		BIT(7)
28
29struct comedi_device;
30struct comedi_subdevice;
31
32#ifdef CONFIG_HAS_IOPORT
33int subdev_8255_io_init(struct comedi_device *dev, struct comedi_subdevice *s,
34			unsigned long regbase);
35#else
36static inline int subdev_8255_io_init(struct comedi_device *dev,
37				      struct comedi_subdevice *s,
38				      unsigned long regbase)
39{
40	return -ENXIO;
41}
42#endif
43
44int subdev_8255_mm_init(struct comedi_device *dev, struct comedi_subdevice *s,
45			unsigned long regbase);
46
47int subdev_8255_cb_init(struct comedi_device *dev, struct comedi_subdevice *s,
48			int (*io)(struct comedi_device *dev, int dir, int port,
49				  int data, unsigned long context),
50			unsigned long context);
51
52unsigned long subdev_8255_regbase(struct comedi_subdevice *s);
53
54#endif