1 // SPDX-License-Identifier: GPL-2.0-only
3 * GPIO driver for the ACCES 104-DIO-48E series
4 * Copyright (C) 2016 William Breathitt Gray
6 * This driver supports the following ACCES devices: 104-DIO-48E and
9 #include <linux/bitmap.h>
10 #include <linux/bitops.h>
11 #include <linux/device.h>
12 #include <linux/errno.h>
13 #include <linux/gpio/driver.h>
15 #include <linux/ioport.h>
16 #include <linux/interrupt.h>
17 #include <linux/irqdesc.h>
18 #include <linux/isa.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/moduleparam.h>
22 #include <linux/spinlock.h>
24 #define DIO48E_EXTENT 16
25 #define MAX_NUM_DIO48E max_num_isa_dev(DIO48E_EXTENT)
27 static unsigned int base
[MAX_NUM_DIO48E
];
28 static unsigned int num_dio48e
;
29 module_param_hw_array(base
, uint
, ioport
, &num_dio48e
, 0);
30 MODULE_PARM_DESC(base
, "ACCES 104-DIO-48E base addresses");
32 static unsigned int irq
[MAX_NUM_DIO48E
];
33 module_param_hw_array(irq
, uint
, irq
, NULL
, 0);
34 MODULE_PARM_DESC(irq
, "ACCES 104-DIO-48E interrupt line numbers");
37 * struct dio48e_gpio - GPIO device private data structure
38 * @chip: instance of the gpio_chip
39 * @io_state: bit I/O state (whether bit is set to input or output)
40 * @out_state: output bits state
41 * @control: Control registers state
42 * @lock: synchronization lock to prevent I/O race conditions
43 * @base: base port address of the GPIO device
44 * @irq_mask: I/O bits affected by interrupts
47 struct gpio_chip chip
;
48 unsigned char io_state
[6];
49 unsigned char out_state
[6];
50 unsigned char control
[2];
53 unsigned char irq_mask
;
56 static int dio48e_gpio_get_direction(struct gpio_chip
*chip
, unsigned offset
)
58 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
59 const unsigned port
= offset
/ 8;
60 const unsigned mask
= BIT(offset
% 8);
62 return !!(dio48egpio
->io_state
[port
] & mask
);
65 static int dio48e_gpio_direction_input(struct gpio_chip
*chip
, unsigned offset
)
67 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
68 const unsigned io_port
= offset
/ 8;
69 const unsigned int control_port
= io_port
/ 3;
70 const unsigned control_addr
= dio48egpio
->base
+ 3 + control_port
*4;
74 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
76 /* Check if configuring Port C */
77 if (io_port
== 2 || io_port
== 5) {
78 /* Port C can be configured by nibble */
80 dio48egpio
->io_state
[io_port
] |= 0xF0;
81 dio48egpio
->control
[control_port
] |= BIT(3);
83 dio48egpio
->io_state
[io_port
] |= 0x0F;
84 dio48egpio
->control
[control_port
] |= BIT(0);
87 dio48egpio
->io_state
[io_port
] |= 0xFF;
88 if (io_port
== 0 || io_port
== 3)
89 dio48egpio
->control
[control_port
] |= BIT(4);
91 dio48egpio
->control
[control_port
] |= BIT(1);
94 control
= BIT(7) | dio48egpio
->control
[control_port
];
95 outb(control
, control_addr
);
97 outb(control
, control_addr
);
99 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
104 static int dio48e_gpio_direction_output(struct gpio_chip
*chip
, unsigned offset
,
107 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
108 const unsigned io_port
= offset
/ 8;
109 const unsigned int control_port
= io_port
/ 3;
110 const unsigned mask
= BIT(offset
% 8);
111 const unsigned control_addr
= dio48egpio
->base
+ 3 + control_port
*4;
112 const unsigned out_port
= (io_port
> 2) ? io_port
+ 1 : io_port
;
116 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
118 /* Check if configuring Port C */
119 if (io_port
== 2 || io_port
== 5) {
120 /* Port C can be configured by nibble */
121 if (offset
% 8 > 3) {
122 dio48egpio
->io_state
[io_port
] &= 0x0F;
123 dio48egpio
->control
[control_port
] &= ~BIT(3);
125 dio48egpio
->io_state
[io_port
] &= 0xF0;
126 dio48egpio
->control
[control_port
] &= ~BIT(0);
129 dio48egpio
->io_state
[io_port
] &= 0x00;
130 if (io_port
== 0 || io_port
== 3)
131 dio48egpio
->control
[control_port
] &= ~BIT(4);
133 dio48egpio
->control
[control_port
] &= ~BIT(1);
137 dio48egpio
->out_state
[io_port
] |= mask
;
139 dio48egpio
->out_state
[io_port
] &= ~mask
;
141 control
= BIT(7) | dio48egpio
->control
[control_port
];
142 outb(control
, control_addr
);
144 outb(dio48egpio
->out_state
[io_port
], dio48egpio
->base
+ out_port
);
147 outb(control
, control_addr
);
149 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
154 static int dio48e_gpio_get(struct gpio_chip
*chip
, unsigned offset
)
156 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
157 const unsigned port
= offset
/ 8;
158 const unsigned mask
= BIT(offset
% 8);
159 const unsigned in_port
= (port
> 2) ? port
+ 1 : port
;
163 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
165 /* ensure that GPIO is set for input */
166 if (!(dio48egpio
->io_state
[port
] & mask
)) {
167 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
171 port_state
= inb(dio48egpio
->base
+ in_port
);
173 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
175 return !!(port_state
& mask
);
178 static int dio48e_gpio_get_multiple(struct gpio_chip
*chip
, unsigned long *mask
,
181 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
183 static const size_t ports
[] = { 0, 1, 2, 4, 5, 6 };
184 const unsigned int gpio_reg_size
= 8;
185 unsigned int bits_offset
;
187 unsigned int word_offset
;
188 unsigned long word_mask
;
189 const unsigned long port_mask
= GENMASK(gpio_reg_size
- 1, 0);
190 unsigned long port_state
;
192 /* clear bits array to a clean slate */
193 bitmap_zero(bits
, chip
->ngpio
);
195 /* get bits are evaluated a gpio port register at a time */
196 for (i
= 0; i
< ARRAY_SIZE(ports
); i
++) {
197 /* gpio offset in bits array */
198 bits_offset
= i
* gpio_reg_size
;
200 /* word index for bits array */
201 word_index
= BIT_WORD(bits_offset
);
203 /* gpio offset within current word of bits array */
204 word_offset
= bits_offset
% BITS_PER_LONG
;
206 /* mask of get bits for current gpio within current word */
207 word_mask
= mask
[word_index
] & (port_mask
<< word_offset
);
209 /* no get bits in this port so skip to next one */
213 /* read bits from current gpio port */
214 port_state
= inb(dio48egpio
->base
+ ports
[i
]);
216 /* store acquired bits at respective bits array offset */
217 bits
[word_index
] |= (port_state
<< word_offset
) & word_mask
;
223 static void dio48e_gpio_set(struct gpio_chip
*chip
, unsigned offset
, int value
)
225 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
226 const unsigned port
= offset
/ 8;
227 const unsigned mask
= BIT(offset
% 8);
228 const unsigned out_port
= (port
> 2) ? port
+ 1 : port
;
231 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
234 dio48egpio
->out_state
[port
] |= mask
;
236 dio48egpio
->out_state
[port
] &= ~mask
;
238 outb(dio48egpio
->out_state
[port
], dio48egpio
->base
+ out_port
);
240 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
243 static void dio48e_gpio_set_multiple(struct gpio_chip
*chip
,
244 unsigned long *mask
, unsigned long *bits
)
246 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
248 const unsigned int gpio_reg_size
= 8;
250 unsigned int out_port
;
251 unsigned int bitmask
;
254 /* set bits are evaluated a gpio register size at a time */
255 for (i
= 0; i
< chip
->ngpio
; i
+= gpio_reg_size
) {
256 /* no more set bits in this mask word; skip to the next word */
257 if (!mask
[BIT_WORD(i
)]) {
258 i
= (BIT_WORD(i
) + 1) * BITS_PER_LONG
- gpio_reg_size
;
262 port
= i
/ gpio_reg_size
;
263 out_port
= (port
> 2) ? port
+ 1 : port
;
264 bitmask
= mask
[BIT_WORD(i
)] & bits
[BIT_WORD(i
)];
266 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
268 /* update output state data and set device gpio register */
269 dio48egpio
->out_state
[port
] &= ~mask
[BIT_WORD(i
)];
270 dio48egpio
->out_state
[port
] |= bitmask
;
271 outb(dio48egpio
->out_state
[port
], dio48egpio
->base
+ out_port
);
273 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
275 /* prepare for next gpio register set */
276 mask
[BIT_WORD(i
)] >>= gpio_reg_size
;
277 bits
[BIT_WORD(i
)] >>= gpio_reg_size
;
281 static void dio48e_irq_ack(struct irq_data
*data
)
285 static void dio48e_irq_mask(struct irq_data
*data
)
287 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(data
);
288 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
289 const unsigned long offset
= irqd_to_hwirq(data
);
292 /* only bit 3 on each respective Port C supports interrupts */
293 if (offset
!= 19 && offset
!= 43)
296 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
299 dio48egpio
->irq_mask
&= ~BIT(0);
301 dio48egpio
->irq_mask
&= ~BIT(1);
303 if (!dio48egpio
->irq_mask
)
304 /* disable interrupts */
305 inb(dio48egpio
->base
+ 0xB);
307 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
310 static void dio48e_irq_unmask(struct irq_data
*data
)
312 struct gpio_chip
*chip
= irq_data_get_irq_chip_data(data
);
313 struct dio48e_gpio
*const dio48egpio
= gpiochip_get_data(chip
);
314 const unsigned long offset
= irqd_to_hwirq(data
);
317 /* only bit 3 on each respective Port C supports interrupts */
318 if (offset
!= 19 && offset
!= 43)
321 raw_spin_lock_irqsave(&dio48egpio
->lock
, flags
);
323 if (!dio48egpio
->irq_mask
) {
324 /* enable interrupts */
325 outb(0x00, dio48egpio
->base
+ 0xF);
326 outb(0x00, dio48egpio
->base
+ 0xB);
330 dio48egpio
->irq_mask
|= BIT(0);
332 dio48egpio
->irq_mask
|= BIT(1);
334 raw_spin_unlock_irqrestore(&dio48egpio
->lock
, flags
);
337 static int dio48e_irq_set_type(struct irq_data
*data
, unsigned flow_type
)
339 const unsigned long offset
= irqd_to_hwirq(data
);
341 /* only bit 3 on each respective Port C supports interrupts */
342 if (offset
!= 19 && offset
!= 43)
345 if (flow_type
!= IRQ_TYPE_NONE
&& flow_type
!= IRQ_TYPE_EDGE_RISING
)
351 static struct irq_chip dio48e_irqchip
= {
352 .name
= "104-dio-48e",
353 .irq_ack
= dio48e_irq_ack
,
354 .irq_mask
= dio48e_irq_mask
,
355 .irq_unmask
= dio48e_irq_unmask
,
356 .irq_set_type
= dio48e_irq_set_type
359 static irqreturn_t
dio48e_irq_handler(int irq
, void *dev_id
)
361 struct dio48e_gpio
*const dio48egpio
= dev_id
;
362 struct gpio_chip
*const chip
= &dio48egpio
->chip
;
363 const unsigned long irq_mask
= dio48egpio
->irq_mask
;
366 for_each_set_bit(gpio
, &irq_mask
, 2)
367 generic_handle_irq(irq_find_mapping(chip
->irq
.domain
,
370 raw_spin_lock(&dio48egpio
->lock
);
372 outb(0x00, dio48egpio
->base
+ 0xF);
374 raw_spin_unlock(&dio48egpio
->lock
);
379 #define DIO48E_NGPIO 48
380 static const char *dio48e_names
[DIO48E_NGPIO
] = {
381 "PPI Group 0 Port A 0", "PPI Group 0 Port A 1", "PPI Group 0 Port A 2",
382 "PPI Group 0 Port A 3", "PPI Group 0 Port A 4", "PPI Group 0 Port A 5",
383 "PPI Group 0 Port A 6", "PPI Group 0 Port A 7", "PPI Group 0 Port B 0",
384 "PPI Group 0 Port B 1", "PPI Group 0 Port B 2", "PPI Group 0 Port B 3",
385 "PPI Group 0 Port B 4", "PPI Group 0 Port B 5", "PPI Group 0 Port B 6",
386 "PPI Group 0 Port B 7", "PPI Group 0 Port C 0", "PPI Group 0 Port C 1",
387 "PPI Group 0 Port C 2", "PPI Group 0 Port C 3", "PPI Group 0 Port C 4",
388 "PPI Group 0 Port C 5", "PPI Group 0 Port C 6", "PPI Group 0 Port C 7",
389 "PPI Group 1 Port A 0", "PPI Group 1 Port A 1", "PPI Group 1 Port A 2",
390 "PPI Group 1 Port A 3", "PPI Group 1 Port A 4", "PPI Group 1 Port A 5",
391 "PPI Group 1 Port A 6", "PPI Group 1 Port A 7", "PPI Group 1 Port B 0",
392 "PPI Group 1 Port B 1", "PPI Group 1 Port B 2", "PPI Group 1 Port B 3",
393 "PPI Group 1 Port B 4", "PPI Group 1 Port B 5", "PPI Group 1 Port B 6",
394 "PPI Group 1 Port B 7", "PPI Group 1 Port C 0", "PPI Group 1 Port C 1",
395 "PPI Group 1 Port C 2", "PPI Group 1 Port C 3", "PPI Group 1 Port C 4",
396 "PPI Group 1 Port C 5", "PPI Group 1 Port C 6", "PPI Group 1 Port C 7"
399 static int dio48e_probe(struct device
*dev
, unsigned int id
)
401 struct dio48e_gpio
*dio48egpio
;
402 const char *const name
= dev_name(dev
);
405 dio48egpio
= devm_kzalloc(dev
, sizeof(*dio48egpio
), GFP_KERNEL
);
409 if (!devm_request_region(dev
, base
[id
], DIO48E_EXTENT
, name
)) {
410 dev_err(dev
, "Unable to lock port addresses (0x%X-0x%X)\n",
411 base
[id
], base
[id
] + DIO48E_EXTENT
);
415 dio48egpio
->chip
.label
= name
;
416 dio48egpio
->chip
.parent
= dev
;
417 dio48egpio
->chip
.owner
= THIS_MODULE
;
418 dio48egpio
->chip
.base
= -1;
419 dio48egpio
->chip
.ngpio
= DIO48E_NGPIO
;
420 dio48egpio
->chip
.names
= dio48e_names
;
421 dio48egpio
->chip
.get_direction
= dio48e_gpio_get_direction
;
422 dio48egpio
->chip
.direction_input
= dio48e_gpio_direction_input
;
423 dio48egpio
->chip
.direction_output
= dio48e_gpio_direction_output
;
424 dio48egpio
->chip
.get
= dio48e_gpio_get
;
425 dio48egpio
->chip
.get_multiple
= dio48e_gpio_get_multiple
;
426 dio48egpio
->chip
.set
= dio48e_gpio_set
;
427 dio48egpio
->chip
.set_multiple
= dio48e_gpio_set_multiple
;
428 dio48egpio
->base
= base
[id
];
430 raw_spin_lock_init(&dio48egpio
->lock
);
432 err
= devm_gpiochip_add_data(dev
, &dio48egpio
->chip
, dio48egpio
);
434 dev_err(dev
, "GPIO registering failed (%d)\n", err
);
438 /* initialize all GPIO as output */
439 outb(0x80, base
[id
] + 3);
440 outb(0x00, base
[id
]);
441 outb(0x00, base
[id
] + 1);
442 outb(0x00, base
[id
] + 2);
443 outb(0x00, base
[id
] + 3);
444 outb(0x80, base
[id
] + 7);
445 outb(0x00, base
[id
] + 4);
446 outb(0x00, base
[id
] + 5);
447 outb(0x00, base
[id
] + 6);
448 outb(0x00, base
[id
] + 7);
450 /* disable IRQ by default */
453 err
= gpiochip_irqchip_add(&dio48egpio
->chip
, &dio48e_irqchip
, 0,
454 handle_edge_irq
, IRQ_TYPE_NONE
);
456 dev_err(dev
, "Could not add irqchip (%d)\n", err
);
460 err
= devm_request_irq(dev
, irq
[id
], dio48e_irq_handler
, 0, name
,
463 dev_err(dev
, "IRQ handler registering failed (%d)\n", err
);
470 static struct isa_driver dio48e_driver
= {
471 .probe
= dio48e_probe
,
473 .name
= "104-dio-48e"
476 module_isa_driver(dio48e_driver
, num_dio48e
);
478 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
479 MODULE_DESCRIPTION("ACCES 104-DIO-48E GPIO driver");
480 MODULE_LICENSE("GPL v2");