2 * GPIO driver for the ACCES 104-DIO-48E series
3 * Copyright (C) 2016 William Breathitt Gray
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2, as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * This driver supports the following ACCES devices: 104-DIO-48E and
17 #include <linux/bitmap.h>
18 #include <linux/bitops.h>
19 #include <linux/device.h>
20 #include <linux/errno.h>
21 #include <linux/gpio/driver.h>
23 #include <linux/ioport.h>
24 #include <linux/interrupt.h>
25 #include <linux/irqdesc.h>
26 #include <linux/isa.h>
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/moduleparam.h>
30 #include <linux/spinlock.h>
32 #define DIO48E_EXTENT 16
33 #define MAX_NUM_DIO48E max_num_isa_dev(DIO48E_EXTENT)
35 static unsigned int base
[MAX_NUM_DIO48E
];
36 static unsigned int num_dio48e
;
37 module_param_hw_array(base
, uint
, ioport
, &num_dio48e
, 0);
38 MODULE_PARM_DESC(base
, "ACCES 104-DIO-48E base addresses");
40 static unsigned int irq
[MAX_NUM_DIO48E
];
41 module_param_hw_array(irq
, uint
, irq
, NULL
, 0);
42 MODULE_PARM_DESC(irq
, "ACCES 104-DIO-48E interrupt line numbers");
45 * struct dio48e_gpio - GPIO device private data structure
46 * @chip: instance of the gpio_chip
47 * @io_state: bit I/O state (whether bit is set to input or output)
48 * @out_state: output bits state
49 * @control: Control registers state
50 * @lock: synchronization lock to prevent I/O race conditions
51 * @base: base port address of the GPIO device
52 * @irq_mask: I/O bits affected by interrupts
55 struct gpio_chip chip
;
56 unsigned char io_state
[6];
57 unsigned char out_state
[6];
58 unsigned char control
[2];
61 unsigned char irq_mask
;
64 static int dio48e_gpio_get_direction(struct gpio_chip
*chip
, unsigned offset
)
66 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
67 const unsigned port
= offset
/ 8;
68 const unsigned mask
= BIT(offset
% 8);
70 return !!(dio48egpio
->io_state
[port
] & mask
);
73 static int dio48e_gpio_direction_input(struct gpio_chip
*chip
, unsigned offset
)
75 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
76 const unsigned io_port
= offset
/ 8;
77 const unsigned int control_port
= io_port
/ 3;
78 const unsigned control_addr
= dio48egpio
->base
+ 3 + control_port
*4;
82 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
84 /* Check if configuring Port C */
85 if (io_port
== 2 || io_port
== 5) {
86 /* Port C can be configured by nibble */
88 dio48egpio
->io_state
[io_port
] |= 0xF0;
89 dio48egpio
->control
[control_port
] |= BIT(3);
91 dio48egpio
->io_state
[io_port
] |= 0x0F;
92 dio48egpio
->control
[control_port
] |= BIT(0);
95 dio48egpio
->io_state
[io_port
] |= 0xFF;
96 if (io_port
== 0 || io_port
== 3)
97 dio48egpio
->control
[control_port
] |= BIT(4);
99 dio48egpio
->control
[control_port
] |= BIT(1);
102 control
= BIT(7) | dio48egpio
->control
[control_port
];
103 outb(control
, control_addr
);
105 outb(control
, control_addr
);
107 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
112 static int dio48e_gpio_direction_output(struct gpio_chip
*chip
, unsigned offset
,
115 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
116 const unsigned io_port
= offset
/ 8;
117 const unsigned int control_port
= io_port
/ 3;
118 const unsigned mask
= BIT(offset
% 8);
119 const unsigned control_addr
= dio48egpio
->base
+ 3 + control_port
*4;
120 const unsigned out_port
= (io_port
> 2) ? io_port
+ 1 : io_port
;
124 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
126 /* Check if configuring Port C */
127 if (io_port
== 2 || io_port
== 5) {
128 /* Port C can be configured by nibble */
129 if (offset
% 8 > 3) {
130 dio48egpio
->io_state
[io_port
] &= 0x0F;
131 dio48egpio
->control
[control_port
] &= ~BIT(3);
133 dio48egpio
->io_state
[io_port
] &= 0xF0;
134 dio48egpio
->control
[control_port
] &= ~BIT(0);
137 dio48egpio
->io_state
[io_port
] &= 0x00;
138 if (io_port
== 0 || io_port
== 3)
139 dio48egpio
->control
[control_port
] &= ~BIT(4);
141 dio48egpio
->control
[control_port
] &= ~BIT(1);
145 dio48egpio
->out_state
[io_port
] |= mask
;
147 dio48egpio
->out_state
[io_port
] &= ~mask
;
149 control
= BIT(7) | dio48egpio
->control
[control_port
];
150 outb(control
, control_addr
);
152 outb(dio48egpio
->out_state
[io_port
], dio48egpio
->base
+ out_port
);
155 outb(control
, control_addr
);
157 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
162 static int dio48e_gpio_get(struct gpio_chip
*chip
, unsigned offset
)
164 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
165 const unsigned port
= offset
/ 8;
166 const unsigned mask
= BIT(offset
% 8);
167 const unsigned in_port
= (port
> 2) ? port
+ 1 : port
;
171 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
173 /* ensure that GPIO is set for input */
174 if (!(dio48egpio
->io_state
[port
] & mask
)) {
175 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
179 port_state
= inb(dio48egpio
->base
+ in_port
);
181 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
183 return !!(port_state
& mask
);
186 static int dio48e_gpio_get_multiple(struct gpio_chip
*chip
, unsigned long *mask
,
189 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
191 static const size_t ports
[] = { 0, 1, 2, 4, 5, 6 };
192 const unsigned int gpio_reg_size
= 8;
193 unsigned int bits_offset
;
195 unsigned int word_offset
;
196 unsigned long word_mask
;
197 const unsigned long port_mask
= GENMASK(gpio_reg_size
- 1, 0);
198 unsigned long port_state
;
200 /* clear bits array to a clean slate */
201 bitmap_zero(bits
, chip
->ngpio
);
203 /* get bits are evaluated a gpio port register at a time */
204 for (i
= 0; i
< ARRAY_SIZE(ports
); i
++) {
205 /* gpio offset in bits array */
206 bits_offset
= i
* gpio_reg_size
;
208 /* word index for bits array */
209 word_index
= BIT_WORD(bits_offset
);
211 /* gpio offset within current word of bits array */
212 word_offset
= bits_offset
% BITS_PER_LONG
;
214 /* mask of get bits for current gpio within current word */
215 word_mask
= mask
[word_index
] & (port_mask
<< word_offset
);
217 /* no get bits in this port so skip to next one */
221 /* read bits from current gpio port */
222 port_state
= inb(dio48egpio
->base
+ ports
[i
]);
224 /* store acquired bits at respective bits array offset */
225 bits
[word_index
] |= port_state
<< word_offset
;
231 static void dio48e_gpio_set(struct gpio_chip
*chip
, unsigned offset
, int value
)
233 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
234 const unsigned port
= offset
/ 8;
235 const unsigned mask
= BIT(offset
% 8);
236 const unsigned out_port
= (port
> 2) ? port
+ 1 : port
;
239 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
242 dio48egpio
->out_state
[port
] |= mask
;
244 dio48egpio
->out_state
[port
] &= ~mask
;
246 outb(dio48egpio
->out_state
[port
], dio48egpio
->base
+ out_port
);
248 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
251 static void dio48e_gpio_set_multiple(struct gpio_chip
*chip
,
252 unsigned long *mask
, unsigned long *bits
)
254 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
256 const unsigned int gpio_reg_size
= 8;
258 unsigned int out_port
;
259 unsigned int bitmask
;
262 /* set bits are evaluated a gpio register size at a time */
263 for (i
= 0; i
< chip
->ngpio
; i
+= gpio_reg_size
) {
264 /* no more set bits in this mask word; skip to the next word */
265 if (!mask
[BIT_WORD(i
)]) {
266 i
= (BIT_WORD(i
) + 1) * BITS_PER_LONG
- gpio_reg_size
;
270 port
= i
/ gpio_reg_size
;
271 out_port
= (port
> 2) ? port
+ 1 : port
;
272 bitmask
= mask
[BIT_WORD(i
)] & bits
[BIT_WORD(i
)];
274 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
276 /* update output state data and set device gpio register */
277 dio48egpio
->out_state
[port
] &= ~mask
[BIT_WORD(i
)];
278 dio48egpio
->out_state
[port
] |= bitmask
;
279 outb(dio48egpio
->out_state
[port
], dio48egpio
->base
+ out_port
);
281 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
283 /* prepare for next gpio register set */
284 mask
[BIT_WORD(i
)] >>= gpio_reg_size
;
285 bits
[BIT_WORD(i
)] >>= gpio_reg_size
;
289 static void dio48e_irq_ack(struct irq_data
*data
)
293 static void dio48e_irq_mask(struct irq_data
*data
)
295 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(data
);
296 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
297 const unsigned long offset
= irqd_to_hwirq(data
);
300 /* only bit 3 on each respective Port C supports interrupts */
301 if (offset
!= 19 && offset
!= 43)
304 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
307 dio48egpio
->irq_mask
&= ~BIT(0);
309 dio48egpio
->irq_mask
&= ~BIT(1);
311 if (!dio48egpio
->irq_mask
)
312 /* disable interrupts */
313 inb(dio48egpio
->base
+ 0xB);
315 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
318 static void dio48e_irq_unmask(struct irq_data
*data
)
320 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(data
);
321 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
322 const unsigned long offset
= irqd_to_hwirq(data
);
325 /* only bit 3 on each respective Port C supports interrupts */
326 if (offset
!= 19 && offset
!= 43)
329 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
331 if (!dio48egpio
->irq_mask
) {
332 /* enable interrupts */
333 outb(0x00, dio48egpio
->base
+ 0xF);
334 outb(0x00, dio48egpio
->base
+ 0xB);
338 dio48egpio
->irq_mask
|= BIT(0);
340 dio48egpio
->irq_mask
|= BIT(1);
342 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
345 static int dio48e_irq_set_type(struct irq_data
*data
, unsigned flow_type
)
347 const unsigned long offset
= irqd_to_hwirq(data
);
349 /* only bit 3 on each respective Port C supports interrupts */
350 if (offset
!= 19 && offset
!= 43)
353 if (flow_type
!= IRQ_TYPE_NONE
&& flow_type
!= IRQ_TYPE_EDGE_RISING
)
359 static struct irq_chip dio48e_irqchip
= {
360 .name
= "104-dio-48e",
361 .irq_ack
= dio48e_irq_ack
,
362 .irq_mask
= dio48e_irq_mask
,
363 .irq_unmask
= dio48e_irq_unmask
,
364 .irq_set_type
= dio48e_irq_set_type
367 static irqreturn_t
dio48e_irq_handler(int irq
, void *dev_id
)
369 struct dio48e_gpio
*const dio48egpio
= dev_id
;
370 struct gpio_chip
*const chip
= &dio48egpio
->chip
;
371 const unsigned long irq_mask
= dio48egpio
->irq_mask
;
374 for_each_set_bit(gpio
, &irq_mask
, 2)
375 generic_handle_irq(irq_find_mapping(chip
->irq
.domain
,
378 raw_spin_lock(&dio48egpio
->lock
);
380 outb(0x00, dio48egpio
->base
+ 0xF);
382 raw_spin_unlock(&dio48egpio
->lock
);
387 #define DIO48E_NGPIO 48
388 static const char *dio48e_names
[DIO48E_NGPIO
] = {
389 "PPI Group 0 Port A 0", "PPI Group 0 Port A 1", "PPI Group 0 Port A 2",
390 "PPI Group 0 Port A 3", "PPI Group 0 Port A 4", "PPI Group 0 Port A 5",
391 "PPI Group 0 Port A 6", "PPI Group 0 Port A 7", "PPI Group 0 Port B 0",
392 "PPI Group 0 Port B 1", "PPI Group 0 Port B 2", "PPI Group 0 Port B 3",
393 "PPI Group 0 Port B 4", "PPI Group 0 Port B 5", "PPI Group 0 Port B 6",
394 "PPI Group 0 Port B 7", "PPI Group 0 Port C 0", "PPI Group 0 Port C 1",
395 "PPI Group 0 Port C 2", "PPI Group 0 Port C 3", "PPI Group 0 Port C 4",
396 "PPI Group 0 Port C 5", "PPI Group 0 Port C 6", "PPI Group 0 Port C 7",
397 "PPI Group 1 Port A 0", "PPI Group 1 Port A 1", "PPI Group 1 Port A 2",
398 "PPI Group 1 Port A 3", "PPI Group 1 Port A 4", "PPI Group 1 Port A 5",
399 "PPI Group 1 Port A 6", "PPI Group 1 Port A 7", "PPI Group 1 Port B 0",
400 "PPI Group 1 Port B 1", "PPI Group 1 Port B 2", "PPI Group 1 Port B 3",
401 "PPI Group 1 Port B 4", "PPI Group 1 Port B 5", "PPI Group 1 Port B 6",
402 "PPI Group 1 Port B 7", "PPI Group 1 Port C 0", "PPI Group 1 Port C 1",
403 "PPI Group 1 Port C 2", "PPI Group 1 Port C 3", "PPI Group 1 Port C 4",
404 "PPI Group 1 Port C 5", "PPI Group 1 Port C 6", "PPI Group 1 Port C 7"
407 static int dio48e_probe(struct device
*dev
, unsigned int id
)
409 struct dio48e_gpio
*dio48egpio
;
410 const char *const name
= dev_name(dev
);
413 dio48egpio
= devm_kzalloc(dev
, sizeof(*dio48egpio
), GFP_KERNEL
);
417 if (!devm_request_region(dev
, base
[id
], DIO48E_EXTENT
, name
)) {
418 dev_err(dev
, "Unable to lock port addresses (0x%X-0x%X)\n",
419 base
[id
], base
[id
] + DIO48E_EXTENT
);
423 dio48egpio
->chip
.label
= name
;
424 dio48egpio
->chip
.parent
= dev
;
425 dio48egpio
->chip
.owner
= THIS_MODULE
;
426 dio48egpio
->chip
.base
= -1;
427 dio48egpio
->chip
.ngpio
= DIO48E_NGPIO
;
428 dio48egpio
->chip
.names
= dio48e_names
;
429 dio48egpio
->chip
.get_direction
= dio48e_gpio_get_direction
;
430 dio48egpio
->chip
.direction_input
= dio48e_gpio_direction_input
;
431 dio48egpio
->chip
.direction_output
= dio48e_gpio_direction_output
;
432 dio48egpio
->chip
.get
= dio48e_gpio_get
;
433 dio48egpio
->chip
.get_multiple
= dio48e_gpio_get_multiple
;
434 dio48egpio
->chip
.set
= dio48e_gpio_set
;
435 dio48egpio
->chip
.set_multiple
= dio48e_gpio_set_multiple
;
436 dio48egpio
->base
= base
[id
];
438 raw_spin_lock_init(&dio48egpio
->lock
);
440 err
= devm_gpiochip_add_data(dev
, &dio48egpio
->chip
, dio48egpio
);
442 dev_err(dev
, "GPIO registering failed (%d)\n", err
);
446 /* initialize all GPIO as output */
447 outb(0x80, base
[id
] + 3);
448 outb(0x00, base
[id
]);
449 outb(0x00, base
[id
] + 1);
450 outb(0x00, base
[id
] + 2);
451 outb(0x00, base
[id
] + 3);
452 outb(0x80, base
[id
] + 7);
453 outb(0x00, base
[id
] + 4);
454 outb(0x00, base
[id
] + 5);
455 outb(0x00, base
[id
] + 6);
456 outb(0x00, base
[id
] + 7);
458 /* disable IRQ by default */
461 err
= gpiochip_irqchip_add(&dio48egpio
->chip
, &dio48e_irqchip
, 0,
462 handle_edge_irq
, IRQ_TYPE_NONE
);
464 dev_err(dev
, "Could not add irqchip (%d)\n", err
);
468 err
= devm_request_irq(dev
, irq
[id
], dio48e_irq_handler
, 0, name
,
471 dev_err(dev
, "IRQ handler registering failed (%d)\n", err
);
478 static struct isa_driver dio48e_driver
= {
479 .probe
= dio48e_probe
,
481 .name
= "104-dio-48e"
484 module_isa_driver(dio48e_driver
, num_dio48e
);
486 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
487 MODULE_DESCRIPTION("ACCES 104-DIO-48E GPIO driver");
488 MODULE_LICENSE("GPL v2");