1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2018 Spreadtrum Communications Inc.
4 * Copyright (C) 2018 Linaro Ltd.
5 */
6
7#include <linux/gpio/driver.h>
8#include <linux/interrupt.h>
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/of_device.h>
12#include <linux/platform_device.h>
13#include <linux/regmap.h>
14
15/* EIC registers definition */
16#define SPRD_PMIC_EIC_DATA 0x0
17#define SPRD_PMIC_EIC_DMSK 0x4
18#define SPRD_PMIC_EIC_IEV 0x14
19#define SPRD_PMIC_EIC_IE 0x18
20#define SPRD_PMIC_EIC_RIS 0x1c
21#define SPRD_PMIC_EIC_MIS 0x20
22#define SPRD_PMIC_EIC_IC 0x24
23#define SPRD_PMIC_EIC_TRIG 0x28
24#define SPRD_PMIC_EIC_CTRL0 0x40
25
26/*
27 * The PMIC EIC controller only has one bank, and each bank now can contain
28 * 16 EICs.
29 */
30#define SPRD_PMIC_EIC_PER_BANK_NR 16
31#define SPRD_PMIC_EIC_NR SPRD_PMIC_EIC_PER_BANK_NR
32#define SPRD_PMIC_EIC_DATA_MASK GENMASK(15, 0)
33#define SPRD_PMIC_EIC_BIT(x) ((x) & (SPRD_PMIC_EIC_PER_BANK_NR - 1))
34#define SPRD_PMIC_EIC_DBNC_MASK GENMASK(11, 0)
35
36/*
37 * These registers are modified under the irq bus lock and cached to avoid
38 * unnecessary writes in bus_sync_unlock.
39 */
40enum {
41 REG_IEV,
42 REG_IE,
43 REG_TRIG,
44 CACHE_NR_REGS
45};
46
47/**
48 * struct sprd_pmic_eic - PMIC EIC controller
49 * @chip: the gpio_chip structure.
50 * @intc: the irq_chip structure.
51 * @regmap: the regmap from the parent device.
52 * @offset: the EIC controller's offset address of the PMIC.
53 * @reg: the array to cache the EIC registers.
54 * @buslock: for bus lock/sync and unlock.
55 * @irq: the interrupt number of the PMIC EIC conteroller.
56 */
57struct sprd_pmic_eic {
58 struct gpio_chip chip;
59 struct irq_chip intc;
60 struct regmap *map;
61 u32 offset;
62 u8 reg[CACHE_NR_REGS];
63 struct mutex buslock;
64 int irq;
65};
66
67static void sprd_pmic_eic_update(struct gpio_chip *chip, unsigned int offset,
68 u16 reg, unsigned int val)
69{
70 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
71 u32 shift = SPRD_PMIC_EIC_BIT(offset);
72
73 regmap_update_bits(pmic_eic->map, pmic_eic->offset + reg,
74 BIT(shift), val << shift);
75}
76
77static int sprd_pmic_eic_read(struct gpio_chip *chip, unsigned int offset,
78 u16 reg)
79{
80 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
81 u32 value;
82 int ret;
83
84 ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
85 if (ret)
86 return ret;
87
88 return !!(value & BIT(SPRD_PMIC_EIC_BIT(offset)));
89}
90
91static int sprd_pmic_eic_request(struct gpio_chip *chip, unsigned int offset)
92{
93 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 1);
94 return 0;
95}
96
97static void sprd_pmic_eic_free(struct gpio_chip *chip, unsigned int offset)
98{
99 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 0);
100}
101
102static int sprd_pmic_eic_get(struct gpio_chip *chip, unsigned int offset)
103{
104 return sprd_pmic_eic_read(chip, offset, SPRD_PMIC_EIC_DATA);
105}
106
107static int sprd_pmic_eic_direction_input(struct gpio_chip *chip,
108 unsigned int offset)
109{
110 /* EICs are always input, nothing need to do here. */
111 return 0;
112}
113
114static void sprd_pmic_eic_set(struct gpio_chip *chip, unsigned int offset,
115 int value)
116{
117 /* EICs are always input, nothing need to do here. */
118}
119
120static int sprd_pmic_eic_set_debounce(struct gpio_chip *chip,
121 unsigned int offset,
122 unsigned int debounce)
123{
124 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
125 u32 reg, value;
126 int ret;
127
128 reg = SPRD_PMIC_EIC_CTRL0 + SPRD_PMIC_EIC_BIT(offset) * 0x4;
129 ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
130 if (ret)
131 return ret;
132
133 value &= ~SPRD_PMIC_EIC_DBNC_MASK;
134 value |= (debounce / 1000) & SPRD_PMIC_EIC_DBNC_MASK;
135 return regmap_write(pmic_eic->map, pmic_eic->offset + reg, value);
136}
137
138static int sprd_pmic_eic_set_config(struct gpio_chip *chip, unsigned int offset,
139 unsigned long config)
140{
141 unsigned long param = pinconf_to_config_param(config);
142 u32 arg = pinconf_to_config_argument(config);
143
144 if (param == PIN_CONFIG_INPUT_DEBOUNCE)
145 return sprd_pmic_eic_set_debounce(chip, offset, arg);
146
147 return -ENOTSUPP;
148}
149
150static void sprd_pmic_eic_irq_mask(struct irq_data *data)
151{
152 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
153 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
154
155 pmic_eic->reg[REG_IE] = 0;
156 pmic_eic->reg[REG_TRIG] = 0;
157}
158
159static void sprd_pmic_eic_irq_unmask(struct irq_data *data)
160{
161 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
162 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
163
164 pmic_eic->reg[REG_IE] = 1;
165 pmic_eic->reg[REG_TRIG] = 1;
166}
167
168static int sprd_pmic_eic_irq_set_type(struct irq_data *data,
169 unsigned int flow_type)
170{
171 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
172 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
173
174 switch (flow_type) {
175 case IRQ_TYPE_LEVEL_HIGH:
176 pmic_eic->reg[REG_IEV] = 1;
177 break;
178 case IRQ_TYPE_LEVEL_LOW:
179 pmic_eic->reg[REG_IEV] = 0;
180 break;
181 case IRQ_TYPE_EDGE_RISING:
182 case IRQ_TYPE_EDGE_FALLING:
183 case IRQ_TYPE_EDGE_BOTH:
184 /*
185 * Will set the trigger level according to current EIC level
186 * in irq_bus_sync_unlock() interface, so here nothing to do.
187 */
188 break;
189 default:
190 return -ENOTSUPP;
191 }
192
193 return 0;
194}
195
196static void sprd_pmic_eic_bus_lock(struct irq_data *data)
197{
198 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
199 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
200
201 mutex_lock(&pmic_eic->buslock);
202}
203
204static void sprd_pmic_eic_bus_sync_unlock(struct irq_data *data)
205{
206 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
207 struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
208 u32 trigger = irqd_get_trigger_type(data);
209 u32 offset = irqd_to_hwirq(data);
210 int state;
211
212 /* Set irq type */
213 if (trigger & IRQ_TYPE_EDGE_BOTH) {
214 state = sprd_pmic_eic_get(chip, offset);
215 if (state)
216 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
217 else
218 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);
219 } else {
220 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV,
221 pmic_eic->reg[REG_IEV]);
222 }
223
224 /* Set irq unmask */
225 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE,
226 pmic_eic->reg[REG_IE]);
227 /* Generate trigger start pulse for debounce EIC */
228 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG,
229 pmic_eic->reg[REG_TRIG]);
230
231 mutex_unlock(&pmic_eic->buslock);
232}
233
234static void sprd_pmic_eic_toggle_trigger(struct gpio_chip *chip,
235 unsigned int irq, unsigned int offset)
236{
237 u32 trigger = irq_get_trigger_type(irq);
238 int state, post_state;
239
240 if (!(trigger & IRQ_TYPE_EDGE_BOTH))
241 return;
242
243 state = sprd_pmic_eic_get(chip, offset);
244retry:
245 if (state)
246 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
247 else
248 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);
249
250 post_state = sprd_pmic_eic_get(chip, offset);
251 if (state != post_state) {
252 dev_warn(chip->parent, "PMIC EIC level was changed.\n");
253 state = post_state;
254 goto retry;
255 }
256
257 /* Set irq unmask */
258 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE, 1);
259 /* Generate trigger start pulse for debounce EIC */
260 sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG, 1);
261}
262
263static irqreturn_t sprd_pmic_eic_irq_handler(int irq, void *data)
264{
265 struct sprd_pmic_eic *pmic_eic = data;
266 struct gpio_chip *chip = &pmic_eic->chip;
267 unsigned long status;
268 u32 n, girq, val;
269 int ret;
270
271 ret = regmap_read(pmic_eic->map, pmic_eic->offset + SPRD_PMIC_EIC_MIS,
272 &val);
273 if (ret)
274 return IRQ_RETVAL(ret);
275
276 status = val & SPRD_PMIC_EIC_DATA_MASK;
277
278 for_each_set_bit(n, &status, chip->ngpio) {
279 /* Clear the interrupt */
280 sprd_pmic_eic_update(chip, n, SPRD_PMIC_EIC_IC, 1);
281
282 girq = irq_find_mapping(chip->irq.domain, n);
283 handle_nested_irq(girq);
284
285 /*
286 * The PMIC EIC can only support level trigger, so we can
287 * toggle the level trigger to emulate the edge trigger.
288 */
289 sprd_pmic_eic_toggle_trigger(chip, girq, n);
290 }
291
292 return IRQ_HANDLED;
293}
294
295static int sprd_pmic_eic_probe(struct platform_device *pdev)
296{
297 struct gpio_irq_chip *irq;
298 struct sprd_pmic_eic *pmic_eic;
299 int ret;
300
301 pmic_eic = devm_kzalloc(&pdev->dev, sizeof(*pmic_eic), GFP_KERNEL);
302 if (!pmic_eic)
303 return -ENOMEM;
304
305 mutex_init(&pmic_eic->buslock);
306
307 pmic_eic->irq = platform_get_irq(pdev, 0);
308 if (pmic_eic->irq < 0) {
309 dev_err(&pdev->dev, "Failed to get PMIC EIC interrupt.\n");
310 return pmic_eic->irq;
311 }
312
313 pmic_eic->map = dev_get_regmap(pdev->dev.parent, NULL);
314 if (!pmic_eic->map)
315 return -ENODEV;
316
317 ret = of_property_read_u32(pdev->dev.of_node, "reg", &pmic_eic->offset);
318 if (ret) {
319 dev_err(&pdev->dev, "Failed to get PMIC EIC base address.\n");
320 return ret;
321 }
322
323 ret = devm_request_threaded_irq(&pdev->dev, pmic_eic->irq, NULL,
324 sprd_pmic_eic_irq_handler,
325 IRQF_ONESHOT | IRQF_NO_SUSPEND,
326 dev_name(&pdev->dev), pmic_eic);
327 if (ret) {
328 dev_err(&pdev->dev, "Failed to request PMIC EIC IRQ.\n");
329 return ret;
330 }
331
332 pmic_eic->chip.label = dev_name(&pdev->dev);
333 pmic_eic->chip.ngpio = SPRD_PMIC_EIC_NR;
334 pmic_eic->chip.base = -1;
335 pmic_eic->chip.parent = &pdev->dev;
336 pmic_eic->chip.of_node = pdev->dev.of_node;
337 pmic_eic->chip.direction_input = sprd_pmic_eic_direction_input;
338 pmic_eic->chip.request = sprd_pmic_eic_request;
339 pmic_eic->chip.free = sprd_pmic_eic_free;
340 pmic_eic->chip.set_config = sprd_pmic_eic_set_config;
341 pmic_eic->chip.set = sprd_pmic_eic_set;
342 pmic_eic->chip.get = sprd_pmic_eic_get;
343
344 pmic_eic->intc.name = dev_name(&pdev->dev);
345 pmic_eic->intc.irq_mask = sprd_pmic_eic_irq_mask;
346 pmic_eic->intc.irq_unmask = sprd_pmic_eic_irq_unmask;
347 pmic_eic->intc.irq_set_type = sprd_pmic_eic_irq_set_type;
348 pmic_eic->intc.irq_bus_lock = sprd_pmic_eic_bus_lock;
349 pmic_eic->intc.irq_bus_sync_unlock = sprd_pmic_eic_bus_sync_unlock;
350 pmic_eic->intc.flags = IRQCHIP_SKIP_SET_WAKE;
351
352 irq = &pmic_eic->chip.irq;
353 irq->chip = &pmic_eic->intc;
354 irq->threaded = true;
355
356 ret = devm_gpiochip_add_data(&pdev->dev, &pmic_eic->chip, pmic_eic);
357 if (ret < 0) {
358 dev_err(&pdev->dev, "Could not register gpiochip %d.\n", ret);
359 return ret;
360 }
361
362 platform_set_drvdata(pdev, pmic_eic);
363 return 0;
364}
365
366static const struct of_device_id sprd_pmic_eic_of_match[] = {
367 { .compatible = "sprd,sc2731-eic", },
368 { /* end of list */ }
369};
370MODULE_DEVICE_TABLE(of, sprd_pmic_eic_of_match);
371
372static struct platform_driver sprd_pmic_eic_driver = {
373 .probe = sprd_pmic_eic_probe,
374 .driver = {
375 .name = "sprd-pmic-eic",
376 .of_match_table = sprd_pmic_eic_of_match,
377 },
378};
379
380module_platform_driver(sprd_pmic_eic_driver);
381
382MODULE_DESCRIPTION("Spreadtrum PMIC EIC driver");
383MODULE_LICENSE("GPL v2");
384