xref: /openbmc/linux/drivers/comedi/drivers/ssv_dnp.c (revision df0e68c1)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * ssv_dnp.c
4  * generic comedi driver for SSV Embedded Systems' DIL/Net-PCs
5  * Copyright (C) 2001 Robert Schwebel <robert@schwebel.de>
6  *
7  * COMEDI - Linux Control and Measurement Device Interface
8  * Copyright (C) 2000 David A. Schleef <ds@schleef.org>
9  */
10 
11 /*
12  * Driver: ssv_dnp
13  * Description: SSV Embedded Systems DIL/Net-PC
14  * Author: Robert Schwebel <robert@schwebel.de>
15  * Devices: [SSV Embedded Systems] DIL/Net-PC 1486 (dnp-1486)
16  * Status: unknown
17  */
18 
19 /* include files ----------------------------------------------------------- */
20 
21 #include <linux/module.h>
22 #include <linux/comedi/comedidev.h>
23 
24 /* Some global definitions: the registers of the DNP ----------------------- */
25 /*                                                                           */
26 /* For port A and B the mode register has bits corresponding to the output   */
27 /* pins, where Bit-N = 0 -> input, Bit-N = 1 -> output. Note that bits       */
28 /* 4 to 7 correspond to pin 0..3 for port C data register. Ensure that bits  */
29 /* 0..3 remain unchanged! For details about Port C Mode Register see         */
30 /* the remarks in dnp_insn_config() below.                                   */
31 
32 #define CSCIR 0x22		/* Chip Setup and Control Index Register     */
33 #define CSCDR 0x23		/* Chip Setup and Control Data Register      */
34 #define PAMR  0xa5		/* Port A Mode Register                      */
35 #define PADR  0xa9		/* Port A Data Register                      */
36 #define PBMR  0xa4		/* Port B Mode Register                      */
37 #define PBDR  0xa8		/* Port B Data Register                      */
38 #define PCMR  0xa3		/* Port C Mode Register                      */
39 #define PCDR  0xa7		/* Port C Data Register                      */
40 
dnp_dio_insn_bits(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)41 static int dnp_dio_insn_bits(struct comedi_device *dev,
42 			     struct comedi_subdevice *s,
43 			     struct comedi_insn *insn,
44 			     unsigned int *data)
45 {
46 	unsigned int mask;
47 	unsigned int val;
48 
49 	/*
50 	 * Ports A and B are straight forward: each bit corresponds to an
51 	 * output pin with the same order. Port C is different: bits 0...3
52 	 * correspond to bits 4...7 of the output register (PCDR).
53 	 */
54 
55 	mask = comedi_dio_update_state(s, data);
56 	if (mask) {
57 		outb(PADR, CSCIR);
58 		outb(s->state & 0xff, CSCDR);
59 
60 		outb(PBDR, CSCIR);
61 		outb((s->state >> 8) & 0xff, CSCDR);
62 
63 		outb(PCDR, CSCIR);
64 		val = inb(CSCDR) & 0x0f;
65 		outb(((s->state >> 12) & 0xf0) | val, CSCDR);
66 	}
67 
68 	outb(PADR, CSCIR);
69 	val = inb(CSCDR);
70 	outb(PBDR, CSCIR);
71 	val |= (inb(CSCDR) << 8);
72 	outb(PCDR, CSCIR);
73 	val |= ((inb(CSCDR) & 0xf0) << 12);
74 
75 	data[1] = val;
76 
77 	return insn->n;
78 }
79 
dnp_dio_insn_config(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)80 static int dnp_dio_insn_config(struct comedi_device *dev,
81 			       struct comedi_subdevice *s,
82 			       struct comedi_insn *insn,
83 			       unsigned int *data)
84 {
85 	unsigned int chan = CR_CHAN(insn->chanspec);
86 	unsigned int mask;
87 	unsigned int val;
88 	int ret;
89 
90 	ret = comedi_dio_insn_config(dev, s, insn, data, 0);
91 	if (ret)
92 		return ret;
93 
94 	if (chan < 8) {			/* Port A */
95 		mask = 1 << chan;
96 		outb(PAMR, CSCIR);
97 	} else if (chan < 16) {		/* Port B */
98 		mask = 1 << (chan - 8);
99 		outb(PBMR, CSCIR);
100 	} else {			/* Port C */
101 		/*
102 		 * We have to pay attention with port C.
103 		 * This is the meaning of PCMR:
104 		 *   Bit in PCMR:              7 6 5 4 3 2 1 0
105 		 *   Corresponding port C pin: d 3 d 2 d 1 d 0   d= don't touch
106 		 *
107 		 * Multiplication by 2 brings bits into correct position
108 		 * for PCMR!
109 		 */
110 		mask = 1 << ((chan - 16) * 2);
111 		outb(PCMR, CSCIR);
112 	}
113 
114 	val = inb(CSCDR);
115 	if (data[0] == COMEDI_OUTPUT)
116 		val |= mask;
117 	else
118 		val &= ~mask;
119 	outb(val, CSCDR);
120 
121 	return insn->n;
122 }
123 
dnp_attach(struct comedi_device * dev,struct comedi_devconfig * it)124 static int dnp_attach(struct comedi_device *dev, struct comedi_devconfig *it)
125 {
126 	struct comedi_subdevice *s;
127 	int ret;
128 
129 	/*
130 	 * We use I/O ports 0x22, 0x23 and 0xa3-0xa9, which are always
131 	 * allocated for the primary 8259, so we don't need to allocate
132 	 * them ourselves.
133 	 */
134 
135 	ret = comedi_alloc_subdevices(dev, 1);
136 	if (ret)
137 		return ret;
138 
139 	s = &dev->subdevices[0];
140 	/* digital i/o subdevice                                             */
141 	s->type = COMEDI_SUBD_DIO;
142 	s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
143 	s->n_chan = 20;
144 	s->maxdata = 1;
145 	s->range_table = &range_digital;
146 	s->insn_bits = dnp_dio_insn_bits;
147 	s->insn_config = dnp_dio_insn_config;
148 
149 	/* configure all ports as input (default)                            */
150 	outb(PAMR, CSCIR);
151 	outb(0x00, CSCDR);
152 	outb(PBMR, CSCIR);
153 	outb(0x00, CSCDR);
154 	outb(PCMR, CSCIR);
155 	outb((inb(CSCDR) & 0xAA), CSCDR);
156 
157 	return 0;
158 }
159 
dnp_detach(struct comedi_device * dev)160 static void dnp_detach(struct comedi_device *dev)
161 {
162 	outb(PAMR, CSCIR);
163 	outb(0x00, CSCDR);
164 	outb(PBMR, CSCIR);
165 	outb(0x00, CSCDR);
166 	outb(PCMR, CSCIR);
167 	outb((inb(CSCDR) & 0xAA), CSCDR);
168 }
169 
170 static struct comedi_driver dnp_driver = {
171 	.driver_name	= "dnp-1486",
172 	.module		= THIS_MODULE,
173 	.attach		= dnp_attach,
174 	.detach		= dnp_detach,
175 };
176 module_comedi_driver(dnp_driver);
177 
178 MODULE_AUTHOR("Comedi https://www.comedi.org");
179 MODULE_DESCRIPTION("Comedi low-level driver");
180 MODULE_LICENSE("GPL");
181