-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathgpio-104-dio-48e.c
400 lines (326 loc) · 10.7 KB
/
gpio-104-dio-48e.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
/*
* GPIO driver for the ACCES 104-DIO-48E series
* Copyright (C) 2016 William Breathitt Gray
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* This driver supports the following ACCES devices: 104-DIO-48E and
* 104-DIO-24E.
*/
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irqdesc.h>
#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/spinlock.h>
#define DIO48E_EXTENT 16
#define MAX_NUM_DIO48E max_num_isa_dev(DIO48E_EXTENT)
static unsigned int base[MAX_NUM_DIO48E];
static unsigned int num_dio48e;
module_param_array(base, uint, &num_dio48e, 0);
MODULE_PARM_DESC(base, "ACCES 104-DIO-48E base addresses");
static unsigned int irq[MAX_NUM_DIO48E];
module_param_array(irq, uint, NULL, 0);
MODULE_PARM_DESC(irq, "ACCES 104-DIO-48E interrupt line numbers");
/**
* struct dio48e_gpio - GPIO device private data structure
* @chip: instance of the gpio_chip
* @io_state: bit I/O state (whether bit is set to input or output)
* @out_state: output bits state
* @control: Control registers state
* @lock: synchronization lock to prevent I/O race conditions
* @base: base port address of the GPIO device
* @irq: Interrupt line number
* @irq_mask: I/O bits affected by interrupts
*/
struct dio48e_gpio {
struct gpio_chip chip;
unsigned char io_state[6];
unsigned char out_state[6];
unsigned char control[2];
spinlock_t lock;
unsigned base;
unsigned irq;
unsigned char irq_mask;
};
static int dio48e_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
{
struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
const unsigned port = offset / 8;
const unsigned mask = BIT(offset % 8);
return !!(dio48egpio->io_state[port] & mask);
}
static int dio48e_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
const unsigned io_port = offset / 8;
const unsigned int control_port = io_port / 3;
const unsigned control_addr = dio48egpio->base + 3 + control_port*4;
unsigned long flags;
unsigned control;
spin_lock_irqsave(&dio48egpio->lock, flags);
/* Check if configuring Port C */
if (io_port == 2 || io_port == 5) {
/* Port C can be configured by nibble */
if (offset % 8 > 3) {
dio48egpio->io_state[io_port] |= 0xF0;
dio48egpio->control[control_port] |= BIT(3);
} else {
dio48egpio->io_state[io_port] |= 0x0F;
dio48egpio->control[control_port] |= BIT(0);
}
} else {
dio48egpio->io_state[io_port] |= 0xFF;
if (io_port == 0 || io_port == 3)
dio48egpio->control[control_port] |= BIT(4);
else
dio48egpio->control[control_port] |= BIT(1);
}
control = BIT(7) | dio48egpio->control[control_port];
outb(control, control_addr);
control &= ~BIT(7);
outb(control, control_addr);
spin_unlock_irqrestore(&dio48egpio->lock, flags);
return 0;
}
static int dio48e_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
int value)
{
struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
const unsigned io_port = offset / 8;
const unsigned int control_port = io_port / 3;
const unsigned mask = BIT(offset % 8);
const unsigned control_addr = dio48egpio->base + 3 + control_port*4;
const unsigned out_port = (io_port > 2) ? io_port + 1 : io_port;
unsigned long flags;
unsigned control;
spin_lock_irqsave(&dio48egpio->lock, flags);
/* Check if configuring Port C */
if (io_port == 2 || io_port == 5) {
/* Port C can be configured by nibble */
if (offset % 8 > 3) {
dio48egpio->io_state[io_port] &= 0x0F;
dio48egpio->control[control_port] &= ~BIT(3);
} else {
dio48egpio->io_state[io_port] &= 0xF0;
dio48egpio->control[control_port] &= ~BIT(0);
}
} else {
dio48egpio->io_state[io_port] &= 0x00;
if (io_port == 0 || io_port == 3)
dio48egpio->control[control_port] &= ~BIT(4);
else
dio48egpio->control[control_port] &= ~BIT(1);
}
if (value)
dio48egpio->out_state[io_port] |= mask;
else
dio48egpio->out_state[io_port] &= ~mask;
control = BIT(7) | dio48egpio->control[control_port];
outb(control, control_addr);
outb(dio48egpio->out_state[io_port], dio48egpio->base + out_port);
control &= ~BIT(7);
outb(control, control_addr);
spin_unlock_irqrestore(&dio48egpio->lock, flags);
return 0;
}
static int dio48e_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
const unsigned port = offset / 8;
const unsigned mask = BIT(offset % 8);
const unsigned in_port = (port > 2) ? port + 1 : port;
unsigned long flags;
unsigned port_state;
spin_lock_irqsave(&dio48egpio->lock, flags);
/* ensure that GPIO is set for input */
if (!(dio48egpio->io_state[port] & mask)) {
spin_unlock_irqrestore(&dio48egpio->lock, flags);
return -EINVAL;
}
port_state = inb(dio48egpio->base + in_port);
spin_unlock_irqrestore(&dio48egpio->lock, flags);
return !!(port_state & mask);
}
static void dio48e_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
const unsigned port = offset / 8;
const unsigned mask = BIT(offset % 8);
const unsigned out_port = (port > 2) ? port + 1 : port;
unsigned long flags;
spin_lock_irqsave(&dio48egpio->lock, flags);
if (value)
dio48egpio->out_state[port] |= mask;
else
dio48egpio->out_state[port] &= ~mask;
outb(dio48egpio->out_state[port], dio48egpio->base + out_port);
spin_unlock_irqrestore(&dio48egpio->lock, flags);
}
static void dio48e_irq_ack(struct irq_data *data)
{
}
static void dio48e_irq_mask(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
const unsigned long offset = irqd_to_hwirq(data);
unsigned long flags;
/* only bit 3 on each respective Port C supports interrupts */
if (offset != 19 && offset != 43)
return;
spin_lock_irqsave(&dio48egpio->lock, flags);
if (offset == 19)
dio48egpio->irq_mask &= ~BIT(0);
else
dio48egpio->irq_mask &= ~BIT(1);
if (!dio48egpio->irq_mask)
/* disable interrupts */
inb(dio48egpio->base + 0xB);
spin_unlock_irqrestore(&dio48egpio->lock, flags);
}
static void dio48e_irq_unmask(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
const unsigned long offset = irqd_to_hwirq(data);
unsigned long flags;
/* only bit 3 on each respective Port C supports interrupts */
if (offset != 19 && offset != 43)
return;
spin_lock_irqsave(&dio48egpio->lock, flags);
if (!dio48egpio->irq_mask) {
/* enable interrupts */
outb(0x00, dio48egpio->base + 0xF);
outb(0x00, dio48egpio->base + 0xB);
}
if (offset == 19)
dio48egpio->irq_mask |= BIT(0);
else
dio48egpio->irq_mask |= BIT(1);
spin_unlock_irqrestore(&dio48egpio->lock, flags);
}
static int dio48e_irq_set_type(struct irq_data *data, unsigned flow_type)
{
const unsigned long offset = irqd_to_hwirq(data);
/* only bit 3 on each respective Port C supports interrupts */
if (offset != 19 && offset != 43)
return -EINVAL;
if (flow_type != IRQ_TYPE_NONE && flow_type != IRQ_TYPE_EDGE_RISING)
return -EINVAL;
return 0;
}
static struct irq_chip dio48e_irqchip = {
.name = "104-dio-48e",
.irq_ack = dio48e_irq_ack,
.irq_mask = dio48e_irq_mask,
.irq_unmask = dio48e_irq_unmask,
.irq_set_type = dio48e_irq_set_type
};
static irqreturn_t dio48e_irq_handler(int irq, void *dev_id)
{
struct dio48e_gpio *const dio48egpio = dev_id;
struct gpio_chip *const chip = &dio48egpio->chip;
const unsigned long irq_mask = dio48egpio->irq_mask;
unsigned long gpio;
for_each_set_bit(gpio, &irq_mask, 2)
generic_handle_irq(irq_find_mapping(chip->irqdomain,
19 + gpio*24));
spin_lock(&dio48egpio->lock);
outb(0x00, dio48egpio->base + 0xF);
spin_unlock(&dio48egpio->lock);
return IRQ_HANDLED;
}
static int dio48e_probe(struct device *dev, unsigned int id)
{
struct dio48e_gpio *dio48egpio;
const char *const name = dev_name(dev);
int err;
dio48egpio = devm_kzalloc(dev, sizeof(*dio48egpio), GFP_KERNEL);
if (!dio48egpio)
return -ENOMEM;
if (!devm_request_region(dev, base[id], DIO48E_EXTENT, name)) {
dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
base[id], base[id] + DIO48E_EXTENT);
return -EBUSY;
}
dio48egpio->chip.label = name;
dio48egpio->chip.parent = dev;
dio48egpio->chip.owner = THIS_MODULE;
dio48egpio->chip.base = -1;
dio48egpio->chip.ngpio = 48;
dio48egpio->chip.get_direction = dio48e_gpio_get_direction;
dio48egpio->chip.direction_input = dio48e_gpio_direction_input;
dio48egpio->chip.direction_output = dio48e_gpio_direction_output;
dio48egpio->chip.get = dio48e_gpio_get;
dio48egpio->chip.set = dio48e_gpio_set;
dio48egpio->base = base[id];
dio48egpio->irq = irq[id];
spin_lock_init(&dio48egpio->lock);
dev_set_drvdata(dev, dio48egpio);
err = gpiochip_add_data(&dio48egpio->chip, dio48egpio);
if (err) {
dev_err(dev, "GPIO registering failed (%d)\n", err);
return err;
}
/* initialize all GPIO as output */
outb(0x80, base[id] + 3);
outb(0x00, base[id]);
outb(0x00, base[id] + 1);
outb(0x00, base[id] + 2);
outb(0x00, base[id] + 3);
outb(0x80, base[id] + 7);
outb(0x00, base[id] + 4);
outb(0x00, base[id] + 5);
outb(0x00, base[id] + 6);
outb(0x00, base[id] + 7);
/* disable IRQ by default */
inb(base[id] + 0xB);
err = gpiochip_irqchip_add(&dio48egpio->chip, &dio48e_irqchip, 0,
handle_edge_irq, IRQ_TYPE_NONE);
if (err) {
dev_err(dev, "Could not add irqchip (%d)\n", err);
goto err_gpiochip_remove;
}
err = request_irq(irq[id], dio48e_irq_handler, 0, name, dio48egpio);
if (err) {
dev_err(dev, "IRQ handler registering failed (%d)\n", err);
goto err_gpiochip_remove;
}
return 0;
err_gpiochip_remove:
gpiochip_remove(&dio48egpio->chip);
return err;
}
static int dio48e_remove(struct device *dev, unsigned int id)
{
struct dio48e_gpio *const dio48egpio = dev_get_drvdata(dev);
free_irq(dio48egpio->irq, dio48egpio);
gpiochip_remove(&dio48egpio->chip);
return 0;
}
static struct isa_driver dio48e_driver = {
.probe = dio48e_probe,
.driver = {
.name = "104-dio-48e"
},
.remove = dio48e_remove
};
module_isa_driver(dio48e_driver, num_dio48e);
MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("ACCES 104-DIO-48E GPIO driver");
MODULE_LICENSE("GPL v2");