xref: /linux/include/linux/comedi/comedi_8255.h (revision 0ea5c948cb64bab5bc7a5516774eb8536f05aa0d)
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 
29 struct comedi_device;
30 struct comedi_subdevice;
31 
32 #ifdef CONFIG_HAS_IOPORT
33 int subdev_8255_io_init(struct comedi_device *dev, struct comedi_subdevice *s,
34 			unsigned long regbase);
35 #else
subdev_8255_io_init(struct comedi_device * dev,struct comedi_subdevice * s,unsigned long regbase)36 static 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 
44 int subdev_8255_mm_init(struct comedi_device *dev, struct comedi_subdevice *s,
45 			unsigned long regbase);
46 
47 int 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 
52 unsigned long subdev_8255_regbase(struct comedi_subdevice *s);
53 
54 #endif
55