1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Intel Whiskey Cove PMIC GPIO Driver
4 *
5 * This driver is written based on gpio-crystalcove.c
6 *
7 * Copyright (C) 2016 Intel Corporation. All rights reserved.
8 */
9
10 #include <linux/bitops.h>
11 #include <linux/gpio/driver.h>
12 #include <linux/interrupt.h>
13 #include <linux/mfd/intel_soc_pmic.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/regmap.h>
17 #include <linux/seq_file.h>
18
19 /*
20 * Whiskey Cove PMIC has 13 physical GPIO pins divided into 3 banks:
21 * Bank 0: Pin 0 - 6
22 * Bank 1: Pin 7 - 10
23 * Bank 2: Pin 11 - 12
24 * Each pin has one output control register and one input control register.
25 */
26 #define BANK0_NR_PINS 7
27 #define BANK1_NR_PINS 4
28 #define BANK2_NR_PINS 2
29 #define WCOVE_GPIO_NUM (BANK0_NR_PINS + BANK1_NR_PINS + BANK2_NR_PINS)
30 #define WCOVE_VGPIO_NUM 94
31 /* GPIO output control registers (one per pin): 0x4e44 - 0x4e50 */
32 #define GPIO_OUT_CTRL_BASE 0x4e44
33 /* GPIO input control registers (one per pin): 0x4e51 - 0x4e5d */
34 #define GPIO_IN_CTRL_BASE 0x4e51
35
36 /*
37 * GPIO interrupts are organized in two groups:
38 * Group 0: Bank 0 pins (Pin 0 - 6)
39 * Group 1: Bank 1 and Bank 2 pins (Pin 7 - 12)
40 * Each group has two registers (one bit per pin): status and mask.
41 */
42 #define GROUP0_NR_IRQS 7
43 #define GROUP1_NR_IRQS 6
44 #define IRQ_MASK_BASE 0x4e19
45 #define IRQ_STATUS_BASE 0x4e0b
46 #define GPIO_IRQ0_MASK GENMASK(6, 0)
47 #define GPIO_IRQ1_MASK GENMASK(5, 0)
48 #define UPDATE_IRQ_TYPE BIT(0)
49 #define UPDATE_IRQ_MASK BIT(1)
50
51 #define CTLI_INTCNT_DIS (0 << 1)
52 #define CTLI_INTCNT_NE (1 << 1)
53 #define CTLI_INTCNT_PE (2 << 1)
54 #define CTLI_INTCNT_BE (3 << 1)
55
56 #define CTLO_DIR_IN (0 << 5)
57 #define CTLO_DIR_OUT (1 << 5)
58
59 #define CTLO_DRV_MASK (1 << 4)
60 #define CTLO_DRV_OD (0 << 4)
61 #define CTLO_DRV_CMOS (1 << 4)
62
63 #define CTLO_DRV_REN (1 << 3)
64
65 #define CTLO_RVAL_2KDOWN (0 << 1)
66 #define CTLO_RVAL_2KUP (1 << 1)
67 #define CTLO_RVAL_50KDOWN (2 << 1)
68 #define CTLO_RVAL_50KUP (3 << 1)
69
70 #define CTLO_INPUT_SET (CTLO_DRV_CMOS | CTLO_DRV_REN | CTLO_RVAL_2KUP)
71 #define CTLO_OUTPUT_SET (CTLO_DIR_OUT | CTLO_INPUT_SET)
72
73 enum ctrl_register {
74 CTRL_IN,
75 CTRL_OUT,
76 IRQ_STATUS,
77 IRQ_MASK,
78 };
79
80 /*
81 * struct wcove_gpio - Whiskey Cove GPIO controller
82 * @buslock: for bus lock/sync and unlock.
83 * @chip: the abstract gpio_chip structure.
84 * @dev: the gpio device
85 * @regmap: the regmap from the parent device.
86 * @regmap_irq_chip: the regmap of the gpio irq chip.
87 * @update: pending IRQ setting update, to be written to the chip upon unlock.
88 * @intcnt: the Interrupt Detect value to be written.
89 * @set_irq_mask: true if the IRQ mask needs to be set, false to clear.
90 */
91 struct wcove_gpio {
92 struct mutex buslock;
93 struct gpio_chip chip;
94 struct device *dev;
95 struct regmap *regmap;
96 struct regmap_irq_chip_data *regmap_irq_chip;
97 int update;
98 int intcnt;
99 bool set_irq_mask;
100 };
101
to_reg(int gpio,enum ctrl_register type)102 static inline int to_reg(int gpio, enum ctrl_register type)
103 {
104 unsigned int reg = type == CTRL_IN ? GPIO_IN_CTRL_BASE : GPIO_OUT_CTRL_BASE;
105
106 if (gpio >= WCOVE_GPIO_NUM)
107 return -ENOTSUPP;
108
109 return reg + gpio;
110 }
111
to_ireg(int gpio,enum ctrl_register type,unsigned int * mask)112 static inline int to_ireg(int gpio, enum ctrl_register type, unsigned int *mask)
113 {
114 unsigned int reg = type == IRQ_STATUS ? IRQ_STATUS_BASE : IRQ_MASK_BASE;
115
116 if (gpio < GROUP0_NR_IRQS) {
117 reg += 0;
118 *mask = BIT(gpio);
119 } else {
120 reg += 1;
121 *mask = BIT(gpio - GROUP0_NR_IRQS);
122 }
123
124 return reg;
125 }
126
wcove_update_irq_mask(struct wcove_gpio * wg,irq_hw_number_t gpio)127 static void wcove_update_irq_mask(struct wcove_gpio *wg, irq_hw_number_t gpio)
128 {
129 unsigned int mask, reg = to_ireg(gpio, IRQ_MASK, &mask);
130
131 if (wg->set_irq_mask)
132 regmap_set_bits(wg->regmap, reg, mask);
133 else
134 regmap_clear_bits(wg->regmap, reg, mask);
135 }
136
wcove_update_irq_ctrl(struct wcove_gpio * wg,irq_hw_number_t gpio)137 static void wcove_update_irq_ctrl(struct wcove_gpio *wg, irq_hw_number_t gpio)
138 {
139 int reg = to_reg(gpio, CTRL_IN);
140
141 regmap_update_bits(wg->regmap, reg, CTLI_INTCNT_BE, wg->intcnt);
142 }
143
wcove_gpio_dir_in(struct gpio_chip * chip,unsigned int gpio)144 static int wcove_gpio_dir_in(struct gpio_chip *chip, unsigned int gpio)
145 {
146 struct wcove_gpio *wg = gpiochip_get_data(chip);
147 int reg = to_reg(gpio, CTRL_OUT);
148
149 if (reg < 0)
150 return 0;
151
152 return regmap_write(wg->regmap, reg, CTLO_INPUT_SET);
153 }
154
wcove_gpio_dir_out(struct gpio_chip * chip,unsigned int gpio,int value)155 static int wcove_gpio_dir_out(struct gpio_chip *chip, unsigned int gpio,
156 int value)
157 {
158 struct wcove_gpio *wg = gpiochip_get_data(chip);
159 int reg = to_reg(gpio, CTRL_OUT);
160
161 if (reg < 0)
162 return 0;
163
164 return regmap_write(wg->regmap, reg, CTLO_OUTPUT_SET | value);
165 }
166
wcove_gpio_get_direction(struct gpio_chip * chip,unsigned int gpio)167 static int wcove_gpio_get_direction(struct gpio_chip *chip, unsigned int gpio)
168 {
169 struct wcove_gpio *wg = gpiochip_get_data(chip);
170 unsigned int val;
171 int ret, reg = to_reg(gpio, CTRL_OUT);
172
173 if (reg < 0)
174 return GPIO_LINE_DIRECTION_OUT;
175
176 ret = regmap_read(wg->regmap, reg, &val);
177 if (ret)
178 return ret;
179
180 if (val & CTLO_DIR_OUT)
181 return GPIO_LINE_DIRECTION_OUT;
182
183 return GPIO_LINE_DIRECTION_IN;
184 }
185
wcove_gpio_get(struct gpio_chip * chip,unsigned int gpio)186 static int wcove_gpio_get(struct gpio_chip *chip, unsigned int gpio)
187 {
188 struct wcove_gpio *wg = gpiochip_get_data(chip);
189 unsigned int val;
190 int ret, reg = to_reg(gpio, CTRL_IN);
191
192 if (reg < 0)
193 return 0;
194
195 ret = regmap_read(wg->regmap, reg, &val);
196 if (ret)
197 return ret;
198
199 return val & 0x1;
200 }
201
wcove_gpio_set(struct gpio_chip * chip,unsigned int gpio,int value)202 static void wcove_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
203 {
204 struct wcove_gpio *wg = gpiochip_get_data(chip);
205 int reg = to_reg(gpio, CTRL_OUT);
206
207 if (reg < 0)
208 return;
209
210 if (value)
211 regmap_set_bits(wg->regmap, reg, 1);
212 else
213 regmap_clear_bits(wg->regmap, reg, 1);
214 }
215
wcove_gpio_set_config(struct gpio_chip * chip,unsigned int gpio,unsigned long config)216 static int wcove_gpio_set_config(struct gpio_chip *chip, unsigned int gpio,
217 unsigned long config)
218 {
219 struct wcove_gpio *wg = gpiochip_get_data(chip);
220 int reg = to_reg(gpio, CTRL_OUT);
221
222 if (reg < 0)
223 return 0;
224
225 switch (pinconf_to_config_param(config)) {
226 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
227 return regmap_update_bits(wg->regmap, reg, CTLO_DRV_MASK,
228 CTLO_DRV_OD);
229 case PIN_CONFIG_DRIVE_PUSH_PULL:
230 return regmap_update_bits(wg->regmap, reg, CTLO_DRV_MASK,
231 CTLO_DRV_CMOS);
232 default:
233 break;
234 }
235
236 return -ENOTSUPP;
237 }
238
wcove_irq_type(struct irq_data * data,unsigned int type)239 static int wcove_irq_type(struct irq_data *data, unsigned int type)
240 {
241 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
242 struct wcove_gpio *wg = gpiochip_get_data(chip);
243 irq_hw_number_t gpio = irqd_to_hwirq(data);
244
245 if (gpio >= WCOVE_GPIO_NUM)
246 return 0;
247
248 switch (type) {
249 case IRQ_TYPE_NONE:
250 wg->intcnt = CTLI_INTCNT_DIS;
251 break;
252 case IRQ_TYPE_EDGE_BOTH:
253 wg->intcnt = CTLI_INTCNT_BE;
254 break;
255 case IRQ_TYPE_EDGE_RISING:
256 wg->intcnt = CTLI_INTCNT_PE;
257 break;
258 case IRQ_TYPE_EDGE_FALLING:
259 wg->intcnt = CTLI_INTCNT_NE;
260 break;
261 default:
262 return -EINVAL;
263 }
264
265 wg->update |= UPDATE_IRQ_TYPE;
266
267 return 0;
268 }
269
wcove_bus_lock(struct irq_data * data)270 static void wcove_bus_lock(struct irq_data *data)
271 {
272 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
273 struct wcove_gpio *wg = gpiochip_get_data(chip);
274
275 mutex_lock(&wg->buslock);
276 }
277
wcove_bus_sync_unlock(struct irq_data * data)278 static void wcove_bus_sync_unlock(struct irq_data *data)
279 {
280 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
281 struct wcove_gpio *wg = gpiochip_get_data(chip);
282 irq_hw_number_t gpio = irqd_to_hwirq(data);
283
284 if (wg->update & UPDATE_IRQ_TYPE)
285 wcove_update_irq_ctrl(wg, gpio);
286 if (wg->update & UPDATE_IRQ_MASK)
287 wcove_update_irq_mask(wg, gpio);
288 wg->update = 0;
289
290 mutex_unlock(&wg->buslock);
291 }
292
wcove_irq_unmask(struct irq_data * data)293 static void wcove_irq_unmask(struct irq_data *data)
294 {
295 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
296 struct wcove_gpio *wg = gpiochip_get_data(chip);
297 irq_hw_number_t gpio = irqd_to_hwirq(data);
298
299 if (gpio >= WCOVE_GPIO_NUM)
300 return;
301
302 gpiochip_enable_irq(chip, gpio);
303
304 wg->set_irq_mask = false;
305 wg->update |= UPDATE_IRQ_MASK;
306 }
307
wcove_irq_mask(struct irq_data * data)308 static void wcove_irq_mask(struct irq_data *data)
309 {
310 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
311 struct wcove_gpio *wg = gpiochip_get_data(chip);
312 irq_hw_number_t gpio = irqd_to_hwirq(data);
313
314 if (gpio >= WCOVE_GPIO_NUM)
315 return;
316
317 wg->set_irq_mask = true;
318 wg->update |= UPDATE_IRQ_MASK;
319
320 gpiochip_disable_irq(chip, gpio);
321 }
322
323 static const struct irq_chip wcove_irqchip = {
324 .name = "Whiskey Cove",
325 .irq_mask = wcove_irq_mask,
326 .irq_unmask = wcove_irq_unmask,
327 .irq_set_type = wcove_irq_type,
328 .irq_bus_lock = wcove_bus_lock,
329 .irq_bus_sync_unlock = wcove_bus_sync_unlock,
330 .flags = IRQCHIP_IMMUTABLE,
331 GPIOCHIP_IRQ_RESOURCE_HELPERS,
332 };
333
wcove_gpio_irq_handler(int irq,void * data)334 static irqreturn_t wcove_gpio_irq_handler(int irq, void *data)
335 {
336 struct wcove_gpio *wg = (struct wcove_gpio *)data;
337 unsigned int virq, gpio;
338 unsigned long pending;
339 u8 p[2];
340
341 if (regmap_bulk_read(wg->regmap, IRQ_STATUS_BASE, p, 2)) {
342 dev_err(wg->dev, "Failed to read irq status register\n");
343 return IRQ_NONE;
344 }
345
346 pending = (p[0] & GPIO_IRQ0_MASK) | ((p[1] & GPIO_IRQ1_MASK) << 7);
347 if (!pending)
348 return IRQ_NONE;
349
350 /* Iterate until no interrupt is pending */
351 while (pending) {
352 /* One iteration is for all pending bits */
353 for_each_set_bit(gpio, &pending, WCOVE_GPIO_NUM) {
354 unsigned int mask, reg = to_ireg(gpio, IRQ_STATUS, &mask);
355
356 virq = irq_find_mapping(wg->chip.irq.domain, gpio);
357 handle_nested_irq(virq);
358 regmap_set_bits(wg->regmap, reg, mask);
359 }
360
361 /* Next iteration */
362 if (regmap_bulk_read(wg->regmap, IRQ_STATUS_BASE, p, 2)) {
363 dev_err(wg->dev, "Failed to read irq status\n");
364 break;
365 }
366
367 pending = (p[0] & GPIO_IRQ0_MASK) | ((p[1] & GPIO_IRQ1_MASK) << 7);
368 }
369
370 return IRQ_HANDLED;
371 }
372
wcove_gpio_dbg_show(struct seq_file * s,struct gpio_chip * chip)373 static void wcove_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
374 {
375 unsigned int ctlo, ctli, irq_mask, irq_status;
376 struct wcove_gpio *wg = gpiochip_get_data(chip);
377 int gpio, mask, ret = 0;
378
379 for (gpio = 0; gpio < WCOVE_GPIO_NUM; gpio++) {
380 ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_OUT), &ctlo);
381 ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_IN), &ctli);
382 if (ret) {
383 dev_err(wg->dev, "Failed to read registers: CTRL out/in\n");
384 break;
385 }
386
387 ret += regmap_read(wg->regmap, to_ireg(gpio, IRQ_MASK, &mask), &irq_mask);
388 ret += regmap_read(wg->regmap, to_ireg(gpio, IRQ_STATUS, &mask), &irq_status);
389 if (ret) {
390 dev_err(wg->dev, "Failed to read registers: IRQ status/mask\n");
391 break;
392 }
393
394 seq_printf(s, " gpio-%-2d %s %s %s %s ctlo=%2x,%s %s\n",
395 gpio, ctlo & CTLO_DIR_OUT ? "out" : "in ",
396 ctli & 0x1 ? "hi" : "lo",
397 ctli & CTLI_INTCNT_NE ? "fall" : " ",
398 ctli & CTLI_INTCNT_PE ? "rise" : " ",
399 ctlo,
400 irq_mask & mask ? "mask " : "unmask",
401 irq_status & mask ? "pending" : " ");
402 }
403 }
404
wcove_gpio_probe(struct platform_device * pdev)405 static int wcove_gpio_probe(struct platform_device *pdev)
406 {
407 struct intel_soc_pmic *pmic;
408 struct wcove_gpio *wg;
409 int virq, ret, irq;
410 struct device *dev;
411 struct gpio_irq_chip *girq;
412
413 /*
414 * This gpio platform device is created by a mfd device (see
415 * drivers/mfd/intel_soc_pmic_bxtwc.c for details). Information
416 * shared by all sub-devices created by the mfd device, the regmap
417 * pointer for instance, is stored as driver data of the mfd device
418 * driver.
419 */
420 pmic = dev_get_drvdata(pdev->dev.parent);
421 if (!pmic)
422 return -ENODEV;
423
424 irq = platform_get_irq(pdev, 0);
425 if (irq < 0)
426 return irq;
427
428 dev = &pdev->dev;
429
430 wg = devm_kzalloc(dev, sizeof(*wg), GFP_KERNEL);
431 if (!wg)
432 return -ENOMEM;
433
434 wg->regmap_irq_chip = pmic->irq_chip_data;
435
436 platform_set_drvdata(pdev, wg);
437
438 mutex_init(&wg->buslock);
439 wg->chip.label = KBUILD_MODNAME;
440 wg->chip.direction_input = wcove_gpio_dir_in;
441 wg->chip.direction_output = wcove_gpio_dir_out;
442 wg->chip.get_direction = wcove_gpio_get_direction;
443 wg->chip.get = wcove_gpio_get;
444 wg->chip.set = wcove_gpio_set;
445 wg->chip.set_config = wcove_gpio_set_config;
446 wg->chip.base = -1;
447 wg->chip.ngpio = WCOVE_VGPIO_NUM;
448 wg->chip.can_sleep = true;
449 wg->chip.parent = pdev->dev.parent;
450 wg->chip.dbg_show = wcove_gpio_dbg_show;
451 wg->dev = dev;
452 wg->regmap = pmic->regmap;
453
454 virq = regmap_irq_get_virq(wg->regmap_irq_chip, irq);
455 if (virq < 0) {
456 dev_err(dev, "Failed to get virq by irq %d\n", irq);
457 return virq;
458 }
459
460 girq = &wg->chip.irq;
461 gpio_irq_chip_set_chip(girq, &wcove_irqchip);
462 /* This will let us handle the parent IRQ in the driver */
463 girq->parent_handler = NULL;
464 girq->num_parents = 0;
465 girq->parents = NULL;
466 girq->default_type = IRQ_TYPE_NONE;
467 girq->handler = handle_simple_irq;
468 girq->threaded = true;
469
470 ret = devm_request_threaded_irq(dev, virq, NULL, wcove_gpio_irq_handler,
471 IRQF_ONESHOT, pdev->name, wg);
472 if (ret) {
473 dev_err(dev, "Failed to request irq %d\n", virq);
474 return ret;
475 }
476
477 ret = devm_gpiochip_add_data(dev, &wg->chip, wg);
478 if (ret) {
479 dev_err(dev, "Failed to add gpiochip: %d\n", ret);
480 return ret;
481 }
482
483 /* Enable GPIO0 interrupts */
484 ret = regmap_clear_bits(wg->regmap, IRQ_MASK_BASE + 0, GPIO_IRQ0_MASK);
485 if (ret)
486 return ret;
487
488 /* Enable GPIO1 interrupts */
489 ret = regmap_clear_bits(wg->regmap, IRQ_MASK_BASE + 1, GPIO_IRQ1_MASK);
490 if (ret)
491 return ret;
492
493 return 0;
494 }
495
496 /*
497 * Whiskey Cove PMIC itself is a analog device(but with digital control
498 * interface) providing power management support for other devices in
499 * the accompanied SoC, so we have no .pm for Whiskey Cove GPIO driver.
500 */
501 static struct platform_driver wcove_gpio_driver = {
502 .driver = {
503 .name = "bxt_wcove_gpio",
504 },
505 .probe = wcove_gpio_probe,
506 };
507
508 module_platform_driver(wcove_gpio_driver);
509
510 MODULE_AUTHOR("Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>");
511 MODULE_AUTHOR("Bin Gao <bin.gao@intel.com>");
512 MODULE_DESCRIPTION("Intel Whiskey Cove GPIO Driver");
513 MODULE_LICENSE("GPL v2");
514 MODULE_ALIAS("platform:bxt_wcove_gpio");
515