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
73enum 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 */
91struct 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
102static 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 -EOPNOTSUPP;
108
109 return reg + gpio;
110}
111
112static 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
127static void wcove_update_irq_mask(struct wcove_gpio *wg, irq_hw_number_t gpio)
128{
129 unsigned int mask, reg = to_ireg(gpio, type: IRQ_MASK, mask: &mask);
130
131 if (wg->set_irq_mask)
132 regmap_set_bits(map: wg->regmap, reg, bits: mask);
133 else
134 regmap_clear_bits(map: wg->regmap, reg, bits: mask);
135}
136
137static void wcove_update_irq_ctrl(struct wcove_gpio *wg, irq_hw_number_t gpio)
138{
139 int reg = to_reg(gpio, type: CTRL_IN);
140
141 regmap_update_bits(map: wg->regmap, reg, CTLI_INTCNT_BE, val: wg->intcnt);
142}
143
144static int wcove_gpio_dir_in(struct gpio_chip *chip, unsigned int gpio)
145{
146 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
147 int reg = to_reg(gpio, type: CTRL_OUT);
148
149 if (reg < 0)
150 return 0;
151
152 return regmap_write(map: wg->regmap, reg, CTLO_INPUT_SET);
153}
154
155static int wcove_gpio_dir_out(struct gpio_chip *chip, unsigned int gpio,
156 int value)
157{
158 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
159 int reg = to_reg(gpio, type: CTRL_OUT);
160
161 if (reg < 0)
162 return 0;
163
164 return regmap_write(map: wg->regmap, reg, CTLO_OUTPUT_SET | value);
165}
166
167static int wcove_gpio_get_direction(struct gpio_chip *chip, unsigned int gpio)
168{
169 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
170 unsigned int val;
171 int ret, reg = to_reg(gpio, type: CTRL_OUT);
172
173 if (reg < 0)
174 return GPIO_LINE_DIRECTION_OUT;
175
176 ret = regmap_read(map: wg->regmap, reg, val: &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
186static int wcove_gpio_get(struct gpio_chip *chip, unsigned int gpio)
187{
188 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
189 unsigned int val;
190 int ret, reg = to_reg(gpio, type: CTRL_IN);
191
192 if (reg < 0)
193 return 0;
194
195 ret = regmap_read(map: wg->regmap, reg, val: &val);
196 if (ret)
197 return ret;
198
199 return val & 0x1;
200}
201
202static void wcove_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
203{
204 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
205 int reg = to_reg(gpio, type: CTRL_OUT);
206
207 if (reg < 0)
208 return;
209
210 if (value)
211 regmap_set_bits(map: wg->regmap, reg, bits: 1);
212 else
213 regmap_clear_bits(map: wg->regmap, reg, bits: 1);
214}
215
216static 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(gc: chip);
220 int reg = to_reg(gpio, type: 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(map: wg->regmap, reg, CTLO_DRV_MASK,
228 CTLO_DRV_OD);
229 case PIN_CONFIG_DRIVE_PUSH_PULL:
230 return regmap_update_bits(map: wg->regmap, reg, CTLO_DRV_MASK,
231 CTLO_DRV_CMOS);
232 default:
233 break;
234 }
235
236 return -ENOTSUPP;
237}
238
239static int wcove_irq_type(struct irq_data *data, unsigned int type)
240{
241 struct gpio_chip *chip = irq_data_get_irq_chip_data(d: data);
242 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
243 irq_hw_number_t gpio = irqd_to_hwirq(d: 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
270static void wcove_bus_lock(struct irq_data *data)
271{
272 struct gpio_chip *chip = irq_data_get_irq_chip_data(d: data);
273 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
274
275 mutex_lock(&wg->buslock);
276}
277
278static void wcove_bus_sync_unlock(struct irq_data *data)
279{
280 struct gpio_chip *chip = irq_data_get_irq_chip_data(d: data);
281 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
282 irq_hw_number_t gpio = irqd_to_hwirq(d: 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(lock: &wg->buslock);
291}
292
293static void wcove_irq_unmask(struct irq_data *data)
294{
295 struct gpio_chip *chip = irq_data_get_irq_chip_data(d: data);
296 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
297 irq_hw_number_t gpio = irqd_to_hwirq(d: data);
298
299 if (gpio >= WCOVE_GPIO_NUM)
300 return;
301
302 gpiochip_enable_irq(gc: chip, offset: gpio);
303
304 wg->set_irq_mask = false;
305 wg->update |= UPDATE_IRQ_MASK;
306}
307
308static void wcove_irq_mask(struct irq_data *data)
309{
310 struct gpio_chip *chip = irq_data_get_irq_chip_data(d: data);
311 struct wcove_gpio *wg = gpiochip_get_data(gc: chip);
312 irq_hw_number_t gpio = irqd_to_hwirq(d: 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(gc: chip, offset: gpio);
321}
322
323static 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
334static 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(map: wg->regmap, IRQ_STATUS_BASE, val: p, val_count: 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, type: IRQ_STATUS, mask: &mask);
355
356 virq = irq_find_mapping(domain: wg->chip.irq.domain, hwirq: gpio);
357 handle_nested_irq(irq: virq);
358 regmap_set_bits(map: wg->regmap, reg, bits: mask);
359 }
360
361 /* Next iteration */
362 if (regmap_bulk_read(map: wg->regmap, IRQ_STATUS_BASE, val: p, val_count: 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
373static 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(gc: chip);
377 int gpio, mask, ret = 0;
378
379 for (gpio = 0; gpio < WCOVE_GPIO_NUM; gpio++) {
380 ret += regmap_read(map: wg->regmap, reg: to_reg(gpio, type: CTRL_OUT), val: &ctlo);
381 ret += regmap_read(map: wg->regmap, reg: to_reg(gpio, type: CTRL_IN), val: &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(map: wg->regmap, reg: to_ireg(gpio, type: IRQ_MASK, mask: &mask), val: &irq_mask);
388 ret += regmap_read(map: wg->regmap, reg: to_ireg(gpio, type: IRQ_STATUS, mask: &mask), val: &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(m: s, fmt: " 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
405static 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(dev: 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, size: 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, data: 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(data: 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, chip: &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, irq: virq, NULL, thread_fn: wcove_gpio_irq_handler,
471 IRQF_ONESHOT, devname: pdev->name, dev_id: 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(map: 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(map: 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 */
501static struct platform_driver wcove_gpio_driver = {
502 .driver = {
503 .name = "bxt_wcove_gpio",
504 },
505 .probe = wcove_gpio_probe,
506};
507
508module_platform_driver(wcove_gpio_driver);
509
510MODULE_AUTHOR("Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>");
511MODULE_AUTHOR("Bin Gao <bin.gao@intel.com>");
512MODULE_DESCRIPTION("Intel Whiskey Cove GPIO Driver");
513MODULE_LICENSE("GPL v2");
514MODULE_ALIAS("platform:bxt_wcove_gpio");
515

source code of linux/drivers/gpio/gpio-wcove.c