1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2010-2011, 2020-2021, The Linux Foundation. All rights reserved.
4 * Copyright (c) 2014, Sony Mobile Communications Inc.
5 */
6
7 #include <linux/delay.h>
8 #include <linux/errno.h>
9 #include <linux/input.h>
10 #include <linux/interrupt.h>
11 #include <linux/kernel.h>
12 #include <linux/ktime.h>
13 #include <linux/log2.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_device.h>
18 #include <linux/platform_device.h>
19 #include <linux/reboot.h>
20 #include <linux/regmap.h>
21
22 #define PON_REV2 0x01
23
24 #define PON_SUBTYPE 0x05
25
26 #define PON_SUBTYPE_PRIMARY 0x01
27 #define PON_SUBTYPE_SECONDARY 0x02
28 #define PON_SUBTYPE_1REG 0x03
29 #define PON_SUBTYPE_GEN2_PRIMARY 0x04
30 #define PON_SUBTYPE_GEN2_SECONDARY 0x05
31 #define PON_SUBTYPE_GEN3_PBS 0x08
32 #define PON_SUBTYPE_GEN3_HLOS 0x09
33
34 #define PON_RT_STS 0x10
35 #define PON_KPDPWR_N_SET BIT(0)
36 #define PON_RESIN_N_SET BIT(1)
37 #define PON_GEN3_RESIN_N_SET BIT(6)
38 #define PON_GEN3_KPDPWR_N_SET BIT(7)
39
40 #define PON_PS_HOLD_RST_CTL 0x5a
41 #define PON_PS_HOLD_RST_CTL2 0x5b
42 #define PON_PS_HOLD_ENABLE BIT(7)
43 #define PON_PS_HOLD_TYPE_MASK 0x0f
44 #define PON_PS_HOLD_TYPE_WARM_RESET 1
45 #define PON_PS_HOLD_TYPE_SHUTDOWN 4
46 #define PON_PS_HOLD_TYPE_HARD_RESET 7
47
48 #define PON_PULL_CTL 0x70
49 #define PON_KPDPWR_PULL_UP BIT(1)
50 #define PON_RESIN_PULL_UP BIT(0)
51
52 #define PON_DBC_CTL 0x71
53 #define PON_DBC_DELAY_MASK 0x7
54
55 struct pm8941_data {
56 unsigned int pull_up_bit;
57 unsigned int status_bit;
58 bool supports_ps_hold_poff_config;
59 bool supports_debounce_config;
60 bool has_pon_pbs;
61 const char *name;
62 const char *phys;
63 };
64
65 struct pm8941_pwrkey {
66 struct device *dev;
67 int irq;
68 u32 baseaddr;
69 u32 pon_pbs_baseaddr;
70 struct regmap *regmap;
71 struct input_dev *input;
72
73 unsigned int revision;
74 unsigned int subtype;
75 struct notifier_block reboot_notifier;
76
77 u32 code;
78 u32 sw_debounce_time_us;
79 ktime_t sw_debounce_end_time;
80 bool last_status;
81 const struct pm8941_data *data;
82 };
83
pm8941_reboot_notify(struct notifier_block * nb,unsigned long code,void * unused)84 static int pm8941_reboot_notify(struct notifier_block *nb,
85 unsigned long code, void *unused)
86 {
87 struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,
88 reboot_notifier);
89 unsigned int enable_reg;
90 unsigned int reset_type;
91 int error;
92
93 /* PMICs with revision 0 have the enable bit in same register as ctrl */
94 if (pwrkey->revision == 0)
95 enable_reg = PON_PS_HOLD_RST_CTL;
96 else
97 enable_reg = PON_PS_HOLD_RST_CTL2;
98
99 error = regmap_update_bits(pwrkey->regmap,
100 pwrkey->baseaddr + enable_reg,
101 PON_PS_HOLD_ENABLE,
102 0);
103 if (error)
104 dev_err(pwrkey->dev,
105 "unable to clear ps hold reset enable: %d\n",
106 error);
107
108 /*
109 * Updates of PON_PS_HOLD_ENABLE requires 3 sleep cycles between
110 * writes.
111 */
112 usleep_range(100, 1000);
113
114 switch (code) {
115 case SYS_HALT:
116 case SYS_POWER_OFF:
117 reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;
118 break;
119 case SYS_RESTART:
120 default:
121 if (reboot_mode == REBOOT_WARM)
122 reset_type = PON_PS_HOLD_TYPE_WARM_RESET;
123 else
124 reset_type = PON_PS_HOLD_TYPE_HARD_RESET;
125 break;
126 }
127
128 error = regmap_update_bits(pwrkey->regmap,
129 pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,
130 PON_PS_HOLD_TYPE_MASK,
131 reset_type);
132 if (error)
133 dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",
134 error);
135
136 error = regmap_update_bits(pwrkey->regmap,
137 pwrkey->baseaddr + enable_reg,
138 PON_PS_HOLD_ENABLE,
139 PON_PS_HOLD_ENABLE);
140 if (error)
141 dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);
142
143 return NOTIFY_DONE;
144 }
145
pm8941_pwrkey_irq(int irq,void * _data)146 static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
147 {
148 struct pm8941_pwrkey *pwrkey = _data;
149 unsigned int sts;
150 int err;
151
152 if (pwrkey->sw_debounce_time_us) {
153 if (ktime_before(ktime_get(), pwrkey->sw_debounce_end_time)) {
154 dev_dbg(pwrkey->dev,
155 "ignoring key event received before debounce end %llu us\n",
156 pwrkey->sw_debounce_end_time);
157 return IRQ_HANDLED;
158 }
159 }
160
161 err = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_RT_STS, &sts);
162 if (err)
163 return IRQ_HANDLED;
164
165 sts &= pwrkey->data->status_bit;
166
167 if (pwrkey->sw_debounce_time_us && !sts)
168 pwrkey->sw_debounce_end_time = ktime_add_us(ktime_get(),
169 pwrkey->sw_debounce_time_us);
170
171 /*
172 * Simulate a press event in case a release event occurred without a
173 * corresponding press event.
174 */
175 if (!pwrkey->last_status && !sts) {
176 input_report_key(pwrkey->input, pwrkey->code, 1);
177 input_sync(pwrkey->input);
178 }
179 pwrkey->last_status = sts;
180
181 input_report_key(pwrkey->input, pwrkey->code, sts);
182 input_sync(pwrkey->input);
183
184 return IRQ_HANDLED;
185 }
186
pm8941_pwrkey_sw_debounce_init(struct pm8941_pwrkey * pwrkey)187 static int pm8941_pwrkey_sw_debounce_init(struct pm8941_pwrkey *pwrkey)
188 {
189 unsigned int val, addr, mask;
190 int error;
191
192 if (pwrkey->data->has_pon_pbs && !pwrkey->pon_pbs_baseaddr) {
193 dev_err(pwrkey->dev,
194 "PON_PBS address missing, can't read HW debounce time\n");
195 return 0;
196 }
197
198 if (pwrkey->pon_pbs_baseaddr)
199 addr = pwrkey->pon_pbs_baseaddr + PON_DBC_CTL;
200 else
201 addr = pwrkey->baseaddr + PON_DBC_CTL;
202 error = regmap_read(pwrkey->regmap, addr, &val);
203 if (error)
204 return error;
205
206 if (pwrkey->subtype >= PON_SUBTYPE_GEN2_PRIMARY)
207 mask = 0xf;
208 else
209 mask = 0x7;
210
211 pwrkey->sw_debounce_time_us =
212 2 * USEC_PER_SEC / (1 << (mask - (val & mask)));
213
214 dev_dbg(pwrkey->dev, "SW debounce time = %u us\n",
215 pwrkey->sw_debounce_time_us);
216
217 return 0;
218 }
219
pm8941_pwrkey_suspend(struct device * dev)220 static int __maybe_unused pm8941_pwrkey_suspend(struct device *dev)
221 {
222 struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
223
224 if (device_may_wakeup(dev))
225 enable_irq_wake(pwrkey->irq);
226
227 return 0;
228 }
229
pm8941_pwrkey_resume(struct device * dev)230 static int __maybe_unused pm8941_pwrkey_resume(struct device *dev)
231 {
232 struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
233
234 if (device_may_wakeup(dev))
235 disable_irq_wake(pwrkey->irq);
236
237 return 0;
238 }
239
240 static SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,
241 pm8941_pwrkey_suspend, pm8941_pwrkey_resume);
242
pm8941_pwrkey_probe(struct platform_device * pdev)243 static int pm8941_pwrkey_probe(struct platform_device *pdev)
244 {
245 struct pm8941_pwrkey *pwrkey;
246 bool pull_up;
247 struct device *parent;
248 struct device_node *regmap_node;
249 const __be32 *addr;
250 u32 req_delay;
251 int error;
252
253 if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))
254 req_delay = 15625;
255
256 if (req_delay > 2000000 || req_delay == 0) {
257 dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);
258 return -EINVAL;
259 }
260
261 pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");
262
263 pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);
264 if (!pwrkey)
265 return -ENOMEM;
266
267 pwrkey->dev = &pdev->dev;
268 pwrkey->data = of_device_get_match_data(&pdev->dev);
269
270 parent = pdev->dev.parent;
271 regmap_node = pdev->dev.of_node;
272 pwrkey->regmap = dev_get_regmap(parent, NULL);
273 if (!pwrkey->regmap) {
274 regmap_node = parent->of_node;
275 /*
276 * We failed to get regmap for parent. Let's see if we are
277 * a child of pon node and read regmap and reg from its
278 * parent.
279 */
280 pwrkey->regmap = dev_get_regmap(parent->parent, NULL);
281 if (!pwrkey->regmap) {
282 dev_err(&pdev->dev, "failed to locate regmap\n");
283 return -ENODEV;
284 }
285 }
286
287 addr = of_get_address(regmap_node, 0, NULL, NULL);
288 if (!addr) {
289 dev_err(&pdev->dev, "reg property missing\n");
290 return -EINVAL;
291 }
292 pwrkey->baseaddr = be32_to_cpup(addr);
293
294 if (pwrkey->data->has_pon_pbs) {
295 /* PON_PBS base address is optional */
296 addr = of_get_address(regmap_node, 1, NULL, NULL);
297 if (addr)
298 pwrkey->pon_pbs_baseaddr = be32_to_cpup(addr);
299 }
300
301 pwrkey->irq = platform_get_irq(pdev, 0);
302 if (pwrkey->irq < 0)
303 return pwrkey->irq;
304
305 error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,
306 &pwrkey->revision);
307 if (error) {
308 dev_err(&pdev->dev, "failed to read revision: %d\n", error);
309 return error;
310 }
311
312 error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_SUBTYPE,
313 &pwrkey->subtype);
314 if (error) {
315 dev_err(&pdev->dev, "failed to read subtype: %d\n", error);
316 return error;
317 }
318
319 error = of_property_read_u32(pdev->dev.of_node, "linux,code",
320 &pwrkey->code);
321 if (error) {
322 dev_dbg(&pdev->dev,
323 "no linux,code assuming power (%d)\n", error);
324 pwrkey->code = KEY_POWER;
325 }
326
327 pwrkey->input = devm_input_allocate_device(&pdev->dev);
328 if (!pwrkey->input) {
329 dev_dbg(&pdev->dev, "unable to allocate input device\n");
330 return -ENOMEM;
331 }
332
333 input_set_capability(pwrkey->input, EV_KEY, pwrkey->code);
334
335 pwrkey->input->name = pwrkey->data->name;
336 pwrkey->input->phys = pwrkey->data->phys;
337
338 if (pwrkey->data->supports_debounce_config) {
339 req_delay = (req_delay << 6) / USEC_PER_SEC;
340 req_delay = ilog2(req_delay);
341
342 error = regmap_update_bits(pwrkey->regmap,
343 pwrkey->baseaddr + PON_DBC_CTL,
344 PON_DBC_DELAY_MASK,
345 req_delay);
346 if (error) {
347 dev_err(&pdev->dev, "failed to set debounce: %d\n",
348 error);
349 return error;
350 }
351 }
352
353 error = pm8941_pwrkey_sw_debounce_init(pwrkey);
354 if (error)
355 return error;
356
357 if (pwrkey->data->pull_up_bit) {
358 error = regmap_update_bits(pwrkey->regmap,
359 pwrkey->baseaddr + PON_PULL_CTL,
360 pwrkey->data->pull_up_bit,
361 pull_up ? pwrkey->data->pull_up_bit :
362 0);
363 if (error) {
364 dev_err(&pdev->dev, "failed to set pull: %d\n", error);
365 return error;
366 }
367 }
368
369 error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,
370 NULL, pm8941_pwrkey_irq,
371 IRQF_ONESHOT,
372 pwrkey->data->name, pwrkey);
373 if (error) {
374 dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);
375 return error;
376 }
377
378 error = input_register_device(pwrkey->input);
379 if (error) {
380 dev_err(&pdev->dev, "failed to register input device: %d\n",
381 error);
382 return error;
383 }
384
385 if (pwrkey->data->supports_ps_hold_poff_config) {
386 pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify;
387 error = register_reboot_notifier(&pwrkey->reboot_notifier);
388 if (error) {
389 dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",
390 error);
391 return error;
392 }
393 }
394
395 platform_set_drvdata(pdev, pwrkey);
396 device_init_wakeup(&pdev->dev, 1);
397
398 return 0;
399 }
400
pm8941_pwrkey_remove(struct platform_device * pdev)401 static int pm8941_pwrkey_remove(struct platform_device *pdev)
402 {
403 struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);
404
405 if (pwrkey->data->supports_ps_hold_poff_config)
406 unregister_reboot_notifier(&pwrkey->reboot_notifier);
407
408 return 0;
409 }
410
411 static const struct pm8941_data pwrkey_data = {
412 .pull_up_bit = PON_KPDPWR_PULL_UP,
413 .status_bit = PON_KPDPWR_N_SET,
414 .name = "pm8941_pwrkey",
415 .phys = "pm8941_pwrkey/input0",
416 .supports_ps_hold_poff_config = true,
417 .supports_debounce_config = true,
418 .has_pon_pbs = false,
419 };
420
421 static const struct pm8941_data resin_data = {
422 .pull_up_bit = PON_RESIN_PULL_UP,
423 .status_bit = PON_RESIN_N_SET,
424 .name = "pm8941_resin",
425 .phys = "pm8941_resin/input0",
426 .supports_ps_hold_poff_config = true,
427 .supports_debounce_config = true,
428 .has_pon_pbs = false,
429 };
430
431 static const struct pm8941_data pon_gen3_pwrkey_data = {
432 .status_bit = PON_GEN3_KPDPWR_N_SET,
433 .name = "pmic_pwrkey",
434 .phys = "pmic_pwrkey/input0",
435 .supports_ps_hold_poff_config = false,
436 .supports_debounce_config = false,
437 .has_pon_pbs = true,
438 };
439
440 static const struct pm8941_data pon_gen3_resin_data = {
441 .status_bit = PON_GEN3_RESIN_N_SET,
442 .name = "pmic_resin",
443 .phys = "pmic_resin/input0",
444 .supports_ps_hold_poff_config = false,
445 .supports_debounce_config = false,
446 .has_pon_pbs = true,
447 };
448
449 static const struct of_device_id pm8941_pwr_key_id_table[] = {
450 { .compatible = "qcom,pm8941-pwrkey", .data = &pwrkey_data },
451 { .compatible = "qcom,pm8941-resin", .data = &resin_data },
452 { .compatible = "qcom,pmk8350-pwrkey", .data = &pon_gen3_pwrkey_data },
453 { .compatible = "qcom,pmk8350-resin", .data = &pon_gen3_resin_data },
454 { }
455 };
456 MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);
457
458 static struct platform_driver pm8941_pwrkey_driver = {
459 .probe = pm8941_pwrkey_probe,
460 .remove = pm8941_pwrkey_remove,
461 .driver = {
462 .name = "pm8941-pwrkey",
463 .pm = &pm8941_pwr_key_pm_ops,
464 .of_match_table = of_match_ptr(pm8941_pwr_key_id_table),
465 },
466 };
467 module_platform_driver(pm8941_pwrkey_driver);
468
469 MODULE_DESCRIPTION("PM8941 Power Key driver");
470 MODULE_LICENSE("GPL v2");
471
