xref: /openbmc/linux/drivers/comedi/drivers/pcm3724.c (revision 9940a756)
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 */
57 struct priv_pcm3724 {
58 	int dio_1;
59 	int dio_2;
60 };
61 
compute_buffer(int config,int devno,struct comedi_subdevice * s)62 static 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 
do_3724_config(struct comedi_device * dev,struct comedi_subdevice * s,int chanspec)86 static 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 
enable_chan(struct comedi_device * dev,struct comedi_subdevice * s,int chanspec)120 static 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 */
subdev_3724_insn_config(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)158 static 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 
pcm3724_attach(struct comedi_device * dev,struct comedi_devconfig * it)186 static 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_init(dev, s, NULL, i * I8255_SIZE);
208 		if (ret)
209 			return ret;
210 		s->insn_config = subdev_3724_insn_config;
211 	}
212 	return 0;
213 }
214 
215 static struct comedi_driver pcm3724_driver = {
216 	.driver_name	= "pcm3724",
217 	.module		= THIS_MODULE,
218 	.attach		= pcm3724_attach,
219 	.detach		= comedi_legacy_detach,
220 };
221 module_comedi_driver(pcm3724_driver);
222 
223 MODULE_AUTHOR("Comedi https://www.comedi.org");
224 MODULE_DESCRIPTION("Comedi driver for Advantech PCM-3724 Digital I/O board");
225 MODULE_LICENSE("GPL");
226