1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * GPIO Chip driver for Analog Devices
4 * ADP5588/ADP5587 I/O Expander and QWERTY Keypad Controller
5 *
6 * Copyright 2009-2010 Analog Devices Inc.
7 */
8
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/slab.h>
12 #include <linux/init.h>
13 #include <linux/i2c.h>
14 #include <linux/gpio/driver.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/of_device.h>
18
19 #include <linux/platform_data/adp5588.h>
20
21 #define DRV_NAME "adp5588-gpio"
22
23 /*
24 * Early pre 4.0 Silicon required to delay readout by at least 25ms,
25 * since the Event Counter Register updated 25ms after the interrupt
26 * asserted.
27 */
28 #define WA_DELAYED_READOUT_REVID(rev) ((rev) < 4)
29
30 struct adp5588_gpio {
31 struct i2c_client *client;
32 struct gpio_chip gpio_chip;
33 struct mutex lock; /* protect cached dir, dat_out */
34 /* protect serialized access to the interrupt controller bus */
35 struct mutex irq_lock;
36 uint8_t dat_out[3];
37 uint8_t dir[3];
38 uint8_t int_lvl_low[3];
39 uint8_t int_lvl_high[3];
40 uint8_t int_en[3];
41 uint8_t irq_mask[3];
42 uint8_t int_input_en[3];
43 };
44
adp5588_gpio_read(struct i2c_client * client,u8 reg)45 static int adp5588_gpio_read(struct i2c_client *client, u8 reg)
46 {
47 int ret = i2c_smbus_read_byte_data(client, reg);
48
49 if (ret < 0)
50 dev_err(&client->dev, "Read Error\n");
51
52 return ret;
53 }
54
adp5588_gpio_write(struct i2c_client * client,u8 reg,u8 val)55 static int adp5588_gpio_write(struct i2c_client *client, u8 reg, u8 val)
56 {
57 int ret = i2c_smbus_write_byte_data(client, reg, val);
58
59 if (ret < 0)
60 dev_err(&client->dev, "Write Error\n");
61
62 return ret;
63 }
64
adp5588_gpio_get_value(struct gpio_chip * chip,unsigned off)65 static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off)
66 {
67 struct adp5588_gpio *dev = gpiochip_get_data(chip);
68 unsigned bank = ADP5588_BANK(off);
69 unsigned bit = ADP5588_BIT(off);
70 int val;
71
72 mutex_lock(&dev->lock);
73
74 if (dev->dir[bank] & bit)
75 val = dev->dat_out[bank];
76 else
77 val = adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + bank);
78
79 mutex_unlock(&dev->lock);
80
81 return !!(val & bit);
82 }
83
adp5588_gpio_set_value(struct gpio_chip * chip,unsigned off,int val)84 static void adp5588_gpio_set_value(struct gpio_chip *chip,
85 unsigned off, int val)
86 {
87 unsigned bank, bit;
88 struct adp5588_gpio *dev = gpiochip_get_data(chip);
89
90 bank = ADP5588_BANK(off);
91 bit = ADP5588_BIT(off);
92
93 mutex_lock(&dev->lock);
94 if (val)
95 dev->dat_out[bank] |= bit;
96 else
97 dev->dat_out[bank] &= ~bit;
98
99 adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
100 dev->dat_out[bank]);
101 mutex_unlock(&dev->lock);
102 }
103
adp5588_gpio_direction_input(struct gpio_chip * chip,unsigned off)104 static int adp5588_gpio_direction_input(struct gpio_chip *chip, unsigned off)
105 {
106 int ret;
107 unsigned bank;
108 struct adp5588_gpio *dev = gpiochip_get_data(chip);
109
110 bank = ADP5588_BANK(off);
111
112 mutex_lock(&dev->lock);
113 dev->dir[bank] &= ~ADP5588_BIT(off);
114 ret = adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, dev->dir[bank]);
115 mutex_unlock(&dev->lock);
116
117 return ret;
118 }
119
adp5588_gpio_direction_output(struct gpio_chip * chip,unsigned off,int val)120 static int adp5588_gpio_direction_output(struct gpio_chip *chip,
121 unsigned off, int val)
122 {
123 int ret;
124 unsigned bank, bit;
125 struct adp5588_gpio *dev = gpiochip_get_data(chip);
126
127 bank = ADP5588_BANK(off);
128 bit = ADP5588_BIT(off);
129
130 mutex_lock(&dev->lock);
131 dev->dir[bank] |= bit;
132
133 if (val)
134 dev->dat_out[bank] |= bit;
135 else
136 dev->dat_out[bank] &= ~bit;
137
138 ret = adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
139 dev->dat_out[bank]);
140 ret |= adp5588_gpio_write(dev->client, GPIO_DIR1 + bank,
141 dev->dir[bank]);
142 mutex_unlock(&dev->lock);
143
144 return ret;
145 }
146
147 #ifdef CONFIG_GPIO_ADP5588_IRQ
148
adp5588_irq_bus_lock(struct irq_data * d)149 static void adp5588_irq_bus_lock(struct irq_data *d)
150 {
151 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
152 struct adp5588_gpio *dev = gpiochip_get_data(gc);
153
154 mutex_lock(&dev->irq_lock);
155 }
156
157 /*
158 * genirq core code can issue chip->mask/unmask from atomic context.
159 * This doesn't work for slow busses where an access needs to sleep.
160 * bus_sync_unlock() is therefore called outside the atomic context,
161 * syncs the current irq mask state with the slow external controller
162 * and unlocks the bus.
163 */
164
adp5588_irq_bus_sync_unlock(struct irq_data * d)165 static void adp5588_irq_bus_sync_unlock(struct irq_data *d)
166 {
167 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
168 struct adp5588_gpio *dev = gpiochip_get_data(gc);
169 int i;
170
171 for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
172 if (dev->int_input_en[i]) {
173 mutex_lock(&dev->lock);
174 dev->dir[i] &= ~dev->int_input_en[i];
175 dev->int_input_en[i] = 0;
176 adp5588_gpio_write(dev->client, GPIO_DIR1 + i,
177 dev->dir[i]);
178 mutex_unlock(&dev->lock);
179 }
180
181 if (dev->int_en[i] ^ dev->irq_mask[i]) {
182 dev->int_en[i] = dev->irq_mask[i];
183 adp5588_gpio_write(dev->client, GPI_EM1 + i,
184 dev->int_en[i]);
185 }
186 }
187
188 mutex_unlock(&dev->irq_lock);
189 }
190
adp5588_irq_mask(struct irq_data * d)191 static void adp5588_irq_mask(struct irq_data *d)
192 {
193 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
194 struct adp5588_gpio *dev = gpiochip_get_data(gc);
195
196 dev->irq_mask[ADP5588_BANK(d->hwirq)] &= ~ADP5588_BIT(d->hwirq);
197 }
198
adp5588_irq_unmask(struct irq_data * d)199 static void adp5588_irq_unmask(struct irq_data *d)
200 {
201 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
202 struct adp5588_gpio *dev = gpiochip_get_data(gc);
203
204 dev->irq_mask[ADP5588_BANK(d->hwirq)] |= ADP5588_BIT(d->hwirq);
205 }
206
adp5588_irq_set_type(struct irq_data * d,unsigned int type)207 static int adp5588_irq_set_type(struct irq_data *d, unsigned int type)
208 {
209 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
210 struct adp5588_gpio *dev = gpiochip_get_data(gc);
211 uint16_t gpio = d->hwirq;
212 unsigned bank, bit;
213
214 bank = ADP5588_BANK(gpio);
215 bit = ADP5588_BIT(gpio);
216
217 dev->int_lvl_low[bank] &= ~bit;
218 dev->int_lvl_high[bank] &= ~bit;
219
220 if (type & IRQ_TYPE_EDGE_BOTH || type & IRQ_TYPE_LEVEL_HIGH)
221 dev->int_lvl_high[bank] |= bit;
222
223 if (type & IRQ_TYPE_EDGE_BOTH || type & IRQ_TYPE_LEVEL_LOW)
224 dev->int_lvl_low[bank] |= bit;
225
226 dev->int_input_en[bank] |= bit;
227
228 return 0;
229 }
230
231 static struct irq_chip adp5588_irq_chip = {
232 .name = "adp5588",
233 .irq_mask = adp5588_irq_mask,
234 .irq_unmask = adp5588_irq_unmask,
235 .irq_bus_lock = adp5588_irq_bus_lock,
236 .irq_bus_sync_unlock = adp5588_irq_bus_sync_unlock,
237 .irq_set_type = adp5588_irq_set_type,
238 };
239
adp5588_irq_handler(int irq,void * devid)240 static irqreturn_t adp5588_irq_handler(int irq, void *devid)
241 {
242 struct adp5588_gpio *dev = devid;
243 int status = adp5588_gpio_read(dev->client, INT_STAT);
244
245 if (status & ADP5588_KE_INT) {
246 int ev_cnt = adp5588_gpio_read(dev->client, KEY_LCK_EC_STAT);
247
248 if (ev_cnt > 0) {
249 int i;
250
251 for (i = 0; i < (ev_cnt & ADP5588_KEC); i++) {
252 int key = adp5588_gpio_read(dev->client,
253 Key_EVENTA + i);
254 /* GPIN events begin at 97,
255 * bit 7 indicates logic level
256 */
257 int gpio = (key & 0x7f) - 97;
258 int lvl = key & (1 << 7);
259 int bank = ADP5588_BANK(gpio);
260 int bit = ADP5588_BIT(gpio);
261
262 if ((lvl && dev->int_lvl_high[bank] & bit) ||
263 (!lvl && dev->int_lvl_low[bank] & bit))
264 handle_nested_irq(irq_find_mapping(
265 dev->gpio_chip.irq.domain, gpio));
266 }
267 }
268 }
269
270 adp5588_gpio_write(dev->client, INT_STAT, status); /* Status is W1C */
271
272 return IRQ_HANDLED;
273 }
274
275
adp5588_irq_init_hw(struct gpio_chip * gc)276 static int adp5588_irq_init_hw(struct gpio_chip *gc)
277 {
278 struct adp5588_gpio *dev = gpiochip_get_data(gc);
279 /* Enable IRQs after registering chip */
280 adp5588_gpio_write(dev->client, CFG,
281 ADP5588_AUTO_INC | ADP5588_INT_CFG | ADP5588_KE_IEN);
282
283 return 0;
284 }
285
adp5588_irq_setup(struct adp5588_gpio * dev)286 static int adp5588_irq_setup(struct adp5588_gpio *dev)
287 {
288 struct i2c_client *client = dev->client;
289 int ret;
290 struct adp5588_gpio_platform_data *pdata =
291 dev_get_platdata(&client->dev);
292 struct gpio_irq_chip *girq;
293
294 adp5588_gpio_write(client, CFG, ADP5588_AUTO_INC);
295 adp5588_gpio_write(client, INT_STAT, -1); /* status is W1C */
296
297 mutex_init(&dev->irq_lock);
298
299 ret = devm_request_threaded_irq(&client->dev, client->irq,
300 NULL, adp5588_irq_handler, IRQF_ONESHOT
301 | IRQF_TRIGGER_FALLING | IRQF_SHARED,
302 dev_name(&client->dev), dev);
303 if (ret) {
304 dev_err(&client->dev, "failed to request irq %d\n",
305 client->irq);
306 return ret;
307 }
308
309 /* This will be registered in the call to devm_gpiochip_add_data() */
310 girq = &dev->gpio_chip.irq;
311 girq->chip = &adp5588_irq_chip;
312 /* This will let us handle the parent IRQ in the driver */
313 girq->parent_handler = NULL;
314 girq->num_parents = 0;
315 girq->parents = NULL;
316 girq->first = pdata ? pdata->irq_base : 0;
317 girq->default_type = IRQ_TYPE_NONE;
318 girq->handler = handle_simple_irq;
319 girq->init_hw = adp5588_irq_init_hw;
320 girq->threaded = true;
321
322 return 0;
323 }
324
325 #else
adp5588_irq_setup(struct adp5588_gpio * dev)326 static int adp5588_irq_setup(struct adp5588_gpio *dev)
327 {
328 struct i2c_client *client = dev->client;
329 dev_warn(&client->dev, "interrupt support not compiled in\n");
330
331 return 0;
332 }
333
334 #endif /* CONFIG_GPIO_ADP5588_IRQ */
335
adp5588_gpio_probe(struct i2c_client * client)336 static int adp5588_gpio_probe(struct i2c_client *client)
337 {
338 struct adp5588_gpio_platform_data *pdata =
339 dev_get_platdata(&client->dev);
340 struct adp5588_gpio *dev;
341 struct gpio_chip *gc;
342 int ret, i, revid;
343 unsigned int pullup_dis_mask = 0;
344
345 if (!i2c_check_functionality(client->adapter,
346 I2C_FUNC_SMBUS_BYTE_DATA)) {
347 dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
348 return -EIO;
349 }
350
351 dev = devm_kzalloc(&client->dev, sizeof(*dev), GFP_KERNEL);
352 if (!dev)
353 return -ENOMEM;
354
355 dev->client = client;
356
357 gc = &dev->gpio_chip;
358 gc->direction_input = adp5588_gpio_direction_input;
359 gc->direction_output = adp5588_gpio_direction_output;
360 gc->get = adp5588_gpio_get_value;
361 gc->set = adp5588_gpio_set_value;
362 gc->can_sleep = true;
363 gc->base = -1;
364 gc->parent = &client->dev;
365
366 if (pdata) {
367 gc->base = pdata->gpio_start;
368 gc->names = pdata->names;
369 pullup_dis_mask = pdata->pullup_dis_mask;
370 }
371
372 gc->ngpio = ADP5588_MAXGPIO;
373 gc->label = client->name;
374 gc->owner = THIS_MODULE;
375
376 mutex_init(&dev->lock);
377
378 ret = adp5588_gpio_read(dev->client, DEV_ID);
379 if (ret < 0)
380 return ret;
381
382 revid = ret & ADP5588_DEVICE_ID_MASK;
383
384 for (i = 0, ret = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
385 dev->dat_out[i] = adp5588_gpio_read(client, GPIO_DAT_OUT1 + i);
386 dev->dir[i] = adp5588_gpio_read(client, GPIO_DIR1 + i);
387 ret |= adp5588_gpio_write(client, KP_GPIO1 + i, 0);
388 ret |= adp5588_gpio_write(client, GPIO_PULL1 + i,
389 (pullup_dis_mask >> (8 * i)) & 0xFF);
390 ret |= adp5588_gpio_write(client, GPIO_INT_EN1 + i, 0);
391 if (ret)
392 return ret;
393 }
394
395 if (client->irq) {
396 if (WA_DELAYED_READOUT_REVID(revid)) {
397 dev_warn(&client->dev, "GPIO int not supported\n");
398 } else {
399 ret = adp5588_irq_setup(dev);
400 if (ret)
401 return ret;
402 }
403 }
404
405 ret = devm_gpiochip_add_data(&client->dev, &dev->gpio_chip, dev);
406 if (ret)
407 return ret;
408
409 if (pdata && pdata->setup) {
410 ret = pdata->setup(client, gc->base, gc->ngpio, pdata->context);
411 if (ret < 0)
412 dev_warn(&client->dev, "setup failed, %d\n", ret);
413 }
414
415 i2c_set_clientdata(client, dev);
416
417 return 0;
418 }
419
adp5588_gpio_remove(struct i2c_client * client)420 static int adp5588_gpio_remove(struct i2c_client *client)
421 {
422 struct adp5588_gpio_platform_data *pdata =
423 dev_get_platdata(&client->dev);
424 struct adp5588_gpio *dev = i2c_get_clientdata(client);
425 int ret;
426
427 if (pdata && pdata->teardown) {
428 ret = pdata->teardown(client,
429 dev->gpio_chip.base, dev->gpio_chip.ngpio,
430 pdata->context);
431 if (ret < 0) {
432 dev_err(&client->dev, "teardown failed %d\n", ret);
433 return ret;
434 }
435 }
436
437 if (dev->client->irq)
438 free_irq(dev->client->irq, dev);
439
440 return 0;
441 }
442
443 static const struct i2c_device_id adp5588_gpio_id[] = {
444 {DRV_NAME, 0},
445 {}
446 };
447 MODULE_DEVICE_TABLE(i2c, adp5588_gpio_id);
448
449 #ifdef CONFIG_OF
450 static const struct of_device_id adp5588_gpio_of_id[] = {
451 { .compatible = "adi," DRV_NAME, },
452 {},
453 };
454 MODULE_DEVICE_TABLE(of, adp5588_gpio_of_id);
455 #endif
456
457 static struct i2c_driver adp5588_gpio_driver = {
458 .driver = {
459 .name = DRV_NAME,
460 .of_match_table = of_match_ptr(adp5588_gpio_of_id),
461 },
462 .probe_new = adp5588_gpio_probe,
463 .remove = adp5588_gpio_remove,
464 .id_table = adp5588_gpio_id,
465 };
466
467 module_i2c_driver(adp5588_gpio_driver);
468
469 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
470 MODULE_DESCRIPTION("GPIO ADP5588 Driver");
471 MODULE_LICENSE("GPL");
472
