1// SPDX-License-Identifier: GPL-2.0
2/*
3 * pcm3724.c
4 * Comedi driver for Advantech PCM-3724 Digital I/O board
5 *
6 * Drew Csillag <drew_csillag@yahoo.com>
7 */
8
9/*
10 * Driver: pcm3724
11 * Description: Advantech PCM-3724
12 * Devices: [Advantech] PCM-3724 (pcm3724)
13 * Author: Drew Csillag <drew_csillag@yahoo.com>
14 * Status: tested
15 *
16 * This is driver for digital I/O boards PCM-3724 with 48 DIO.
17 * It needs 8255.o for operations and only immediate mode is supported.
18 * See the source for configuration details.
19 *
20 * Copy/pasted/hacked from pcm724.c
21 *
22 * Configuration Options:
23 *   [0] - I/O port base address
24 */
25
26#include <linux/module.h>
27#include <linux/comedi/comedidev.h>
28#include <linux/comedi/comedi_8255.h>
29
30/*
31 * Register I/O Map
32 *
33 * This board has two standard 8255 devices that provide six 8-bit DIO ports
34 * (48 channels total). Six 74HCT245 chips (one for each port) buffer the
35 * I/O lines to increase driving capability. Because the 74HCT245 is a
36 * bidirectional, tri-state line buffer, two additional I/O ports are used
37 * to control the direction of data and the enable of each port.
38 */
39#define PCM3724_8255_0_BASE		0x00
40#define PCM3724_8255_1_BASE		0x04
41#define PCM3724_DIO_DIR_REG		0x08
42#define PCM3724_DIO_DIR_C0_OUT		BIT(0)
43#define PCM3724_DIO_DIR_B0_OUT		BIT(1)
44#define PCM3724_DIO_DIR_A0_OUT		BIT(2)
45#define PCM3724_DIO_DIR_C1_OUT		BIT(3)
46#define PCM3724_DIO_DIR_B1_OUT		BIT(4)
47#define PCM3724_DIO_DIR_A1_OUT		BIT(5)
48#define PCM3724_GATE_CTRL_REG		0x09
49#define PCM3724_GATE_CTRL_C0_ENA	BIT(0)
50#define PCM3724_GATE_CTRL_B0_ENA	BIT(1)
51#define PCM3724_GATE_CTRL_A0_ENA	BIT(2)
52#define PCM3724_GATE_CTRL_C1_ENA	BIT(3)
53#define PCM3724_GATE_CTRL_B1_ENA	BIT(4)
54#define PCM3724_GATE_CTRL_A1_ENA	BIT(5)
55
56/* used to track configured dios */
57struct priv_pcm3724 {
58	int dio_1;
59	int dio_2;
60};
61
62static int compute_buffer(int config, int devno, struct comedi_subdevice *s)
63{
64	/* 1 in io_bits indicates output */
65	if (s->io_bits & 0x0000ff) {
66		if (devno == 0)
67			config |= PCM3724_DIO_DIR_A0_OUT;
68		else
69			config |= PCM3724_DIO_DIR_A1_OUT;
70	}
71	if (s->io_bits & 0x00ff00) {
72		if (devno == 0)
73			config |= PCM3724_DIO_DIR_B0_OUT;
74		else
75			config |= PCM3724_DIO_DIR_B1_OUT;
76	}
77	if (s->io_bits & 0xff0000) {
78		if (devno == 0)
79			config |= PCM3724_DIO_DIR_C0_OUT;
80		else
81			config |= PCM3724_DIO_DIR_C1_OUT;
82	}
83	return config;
84}
85
86static void do_3724_config(struct comedi_device *dev,
87			   struct comedi_subdevice *s, int chanspec)
88{
89	struct comedi_subdevice *s_dio1 = &dev->subdevices[0];
90	struct comedi_subdevice *s_dio2 = &dev->subdevices[1];
91	int config;
92	int buffer_config;
93	unsigned long port_8255_cfg;
94
95	config = I8255_CTRL_CW;
96
97	/* 1 in io_bits indicates output, 1 in config indicates input */
98	if (!(s->io_bits & 0x0000ff))
99		config |= I8255_CTRL_A_IO;
100
101	if (!(s->io_bits & 0x00ff00))
102		config |= I8255_CTRL_B_IO;
103
104	if (!(s->io_bits & 0xff0000))
105		config |= I8255_CTRL_C_HI_IO | I8255_CTRL_C_LO_IO;
106
107	buffer_config = compute_buffer(0, 0, s_dio1);
108	buffer_config = compute_buffer(buffer_config, 1, s_dio2);
109
110	if (s == s_dio1)
111		port_8255_cfg = dev->iobase + I8255_CTRL_REG;
112	else
113		port_8255_cfg = dev->iobase + I8255_SIZE + I8255_CTRL_REG;
114
115	outb(buffer_config, dev->iobase + PCM3724_DIO_DIR_REG);
116
117	outb(config, port_8255_cfg);
118}
119
120static void enable_chan(struct comedi_device *dev, struct comedi_subdevice *s,
121			int chanspec)
122{
123	struct priv_pcm3724 *priv = dev->private;
124	struct comedi_subdevice *s_dio1 = &dev->subdevices[0];
125	unsigned int mask;
126	int gatecfg;
127
128	gatecfg = 0;
129
130	mask = 1 << CR_CHAN(chanspec);
131	if (s == s_dio1)
132		priv->dio_1 |= mask;
133	else
134		priv->dio_2 |= mask;
135
136	if (priv->dio_1 & 0xff0000)
137		gatecfg |= PCM3724_GATE_CTRL_C0_ENA;
138
139	if (priv->dio_1 & 0xff00)
140		gatecfg |= PCM3724_GATE_CTRL_B0_ENA;
141
142	if (priv->dio_1 & 0xff)
143		gatecfg |= PCM3724_GATE_CTRL_A0_ENA;
144
145	if (priv->dio_2 & 0xff0000)
146		gatecfg |= PCM3724_GATE_CTRL_C1_ENA;
147
148	if (priv->dio_2 & 0xff00)
149		gatecfg |= PCM3724_GATE_CTRL_B1_ENA;
150
151	if (priv->dio_2 & 0xff)
152		gatecfg |= PCM3724_GATE_CTRL_A1_ENA;
153
154	outb(gatecfg, dev->iobase + PCM3724_GATE_CTRL_REG);
155}
156
157/* overriding the 8255 insn config */
158static int subdev_3724_insn_config(struct comedi_device *dev,
159				   struct comedi_subdevice *s,
160				   struct comedi_insn *insn,
161				   unsigned int *data)
162{
163	unsigned int chan = CR_CHAN(insn->chanspec);
164	unsigned int mask;
165	int ret;
166
167	if (chan < 8)
168		mask = 0x0000ff;
169	else if (chan < 16)
170		mask = 0x00ff00;
171	else if (chan < 20)
172		mask = 0x0f0000;
173	else
174		mask = 0xf00000;
175
176	ret = comedi_dio_insn_config(dev, s, insn, data, mask);
177	if (ret)
178		return ret;
179
180	do_3724_config(dev, s, insn->chanspec);
181	enable_chan(dev, s, insn->chanspec);
182
183	return insn->n;
184}
185
186static int pcm3724_attach(struct comedi_device *dev,
187			  struct comedi_devconfig *it)
188{
189	struct priv_pcm3724 *priv;
190	struct comedi_subdevice *s;
191	int ret, i;
192
193	priv = comedi_alloc_devpriv(dev, sizeof(*priv));
194	if (!priv)
195		return -ENOMEM;
196
197	ret = comedi_request_region(dev, it->options[0], 0x10);
198	if (ret)
199		return ret;
200
201	ret = comedi_alloc_subdevices(dev, 2);
202	if (ret)
203		return ret;
204
205	for (i = 0; i < dev->n_subdevices; i++) {
206		s = &dev->subdevices[i];
207		ret = subdev_8255_io_init(dev, s, i * I8255_SIZE);
208		if (ret)
209			return ret;
210		s->insn_config = subdev_3724_insn_config;
211	}
212	return 0;
213}
214
215static struct comedi_driver pcm3724_driver = {
216	.driver_name	= "pcm3724",
217	.module		= THIS_MODULE,
218	.attach		= pcm3724_attach,
219	.detach		= comedi_legacy_detach,
220};
221module_comedi_driver(pcm3724_driver);
222
223MODULE_AUTHOR("Comedi https://www.comedi.org");
224MODULE_DESCRIPTION("Comedi driver for Advantech PCM-3724 Digital I/O board");
225MODULE_LICENSE("GPL");
226