1/*
2 * axp20x power button driver.
3 *
4 * Copyright (C) 2013 Carlo Caione <carlo@caione.org>
5 *
6 * This file is subject to the terms and conditions of the GNU General
7 * Public License. See the file "COPYING" in the main directory of this
8 * archive for more details.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/acpi.h>
17#include <linux/errno.h>
18#include <linux/irq.h>
19#include <linux/init.h>
20#include <linux/input.h>
21#include <linux/interrupt.h>
22#include <linux/kernel.h>
23#include <linux/mfd/axp20x.h>
24#include <linux/module.h>
25#include <linux/platform_device.h>
26#include <linux/regmap.h>
27#include <linux/slab.h>
28
29#define AXP20X_PEK_STARTUP_MASK		(0xc0)
30#define AXP20X_PEK_SHUTDOWN_MASK	(0x03)
31
32struct axp20x_info {
33	const struct axp20x_time *startup_time;
34	unsigned int startup_mask;
35	const struct axp20x_time *shutdown_time;
36	unsigned int shutdown_mask;
37};
38
39struct axp20x_pek {
40	struct axp20x_dev *axp20x;
41	struct input_dev *input;
42	struct axp20x_info *info;
43	int irq_dbr;
44	int irq_dbf;
45};
46
47struct axp20x_time {
48	unsigned int time;
49	unsigned int idx;
50};
51
52static const struct axp20x_time startup_time[] = {
53	{ .time = 128,  .idx = 0 },
54	{ .time = 1000, .idx = 2 },
55	{ .time = 3000, .idx = 1 },
56	{ .time = 2000, .idx = 3 },
57};
58
59static const struct axp20x_time axp221_startup_time[] = {
60	{ .time = 128,  .idx = 0 },
61	{ .time = 1000, .idx = 1 },
62	{ .time = 2000, .idx = 2 },
63	{ .time = 3000, .idx = 3 },
64};
65
66static const struct axp20x_time shutdown_time[] = {
67	{ .time = 4000,  .idx = 0 },
68	{ .time = 6000,  .idx = 1 },
69	{ .time = 8000,  .idx = 2 },
70	{ .time = 10000, .idx = 3 },
71};
72
73static const struct axp20x_info axp20x_info = {
74	.startup_time = startup_time,
75	.startup_mask = AXP20X_PEK_STARTUP_MASK,
76	.shutdown_time = shutdown_time,
77	.shutdown_mask = AXP20X_PEK_SHUTDOWN_MASK,
78};
79
80static const struct axp20x_info axp221_info = {
81	.startup_time = axp221_startup_time,
82	.startup_mask = AXP20X_PEK_STARTUP_MASK,
83	.shutdown_time = shutdown_time,
84	.shutdown_mask = AXP20X_PEK_SHUTDOWN_MASK,
85};
86
87static ssize_t axp20x_show_attr(struct device *dev,
88				const struct axp20x_time *time,
89				unsigned int mask, char *buf)
90{
91	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
92	unsigned int val;
93	int ret, i;
94
95	ret = regmap_read(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY, &val);
96	if (ret != 0)
97		return ret;
98
99	val &= mask;
100	val >>= ffs(mask) - 1;
101
102	for (i = 0; i < 4; i++)
103		if (val == time[i].idx)
104			val = time[i].time;
105
106	return sprintf(buf, "%u\n", val);
107}
108
109static ssize_t axp20x_show_attr_startup(struct device *dev,
110					struct device_attribute *attr,
111					char *buf)
112{
113	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
114
115	return axp20x_show_attr(dev, axp20x_pek->info->startup_time,
116				axp20x_pek->info->startup_mask, buf);
117}
118
119static ssize_t axp20x_show_attr_shutdown(struct device *dev,
120					 struct device_attribute *attr,
121					 char *buf)
122{
123	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
124
125	return axp20x_show_attr(dev, axp20x_pek->info->shutdown_time,
126				axp20x_pek->info->shutdown_mask, buf);
127}
128
129static ssize_t axp20x_store_attr(struct device *dev,
130				 const struct axp20x_time *time,
131				 unsigned int mask, const char *buf,
132				 size_t count)
133{
134	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
135	char val_str[20];
136	size_t len;
137	int ret, i;
138	unsigned int val, idx = 0;
139	unsigned int best_err = UINT_MAX;
140
141	val_str[sizeof(val_str) - 1] = '\0';
142	strncpy(val_str, buf, sizeof(val_str) - 1);
143	len = strlen(val_str);
144
145	if (len && val_str[len - 1] == '\n')
146		val_str[len - 1] = '\0';
147
148	ret = kstrtouint(val_str, 10, &val);
149	if (ret)
150		return ret;
151
152	for (i = 3; i >= 0; i--) {
153		unsigned int err;
154
155		err = abs(time[i].time - val);
156		if (err < best_err) {
157			best_err = err;
158			idx = time[i].idx;
159		}
160
161		if (!err)
162			break;
163	}
164
165	idx <<= ffs(mask) - 1;
166	ret = regmap_update_bits(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY,
167				 mask, idx);
168	if (ret != 0)
169		return -EINVAL;
170
171	return count;
172}
173
174static ssize_t axp20x_store_attr_startup(struct device *dev,
175					 struct device_attribute *attr,
176					 const char *buf, size_t count)
177{
178	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
179
180	return axp20x_store_attr(dev, axp20x_pek->info->startup_time,
181				 axp20x_pek->info->startup_mask, buf, count);
182}
183
184static ssize_t axp20x_store_attr_shutdown(struct device *dev,
185					  struct device_attribute *attr,
186					  const char *buf, size_t count)
187{
188	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
189
190	return axp20x_store_attr(dev, axp20x_pek->info->shutdown_time,
191				 axp20x_pek->info->shutdown_mask, buf, count);
192}
193
194static DEVICE_ATTR(startup, 0644, axp20x_show_attr_startup,
195		   axp20x_store_attr_startup);
196static DEVICE_ATTR(shutdown, 0644, axp20x_show_attr_shutdown,
197		   axp20x_store_attr_shutdown);
198
199static struct attribute *axp20x_attrs[] = {
200	&dev_attr_startup.attr,
201	&dev_attr_shutdown.attr,
202	NULL,
203};
204ATTRIBUTE_GROUPS(axp20x);
205
206static irqreturn_t axp20x_pek_irq(int irq, void *pwr)
207{
208	struct axp20x_pek *axp20x_pek = pwr;
209	struct input_dev *idev = axp20x_pek->input;
210
211	if (!idev)
212		return IRQ_HANDLED;
213
214	/*
215	 * The power-button is connected to ground so a falling edge (dbf)
216	 * means it is pressed.
217	 */
218	if (irq == axp20x_pek->irq_dbf)
219		input_report_key(idev, KEY_POWER, true);
220	else if (irq == axp20x_pek->irq_dbr)
221		input_report_key(idev, KEY_POWER, false);
222
223	input_sync(idev);
224
225	return IRQ_HANDLED;
226}
227
228static int axp20x_pek_probe_input_device(struct axp20x_pek *axp20x_pek,
229					 struct platform_device *pdev)
230{
231	struct input_dev *idev;
232	int error;
233
234	axp20x_pek->input = devm_input_allocate_device(&pdev->dev);
235	if (!axp20x_pek->input)
236		return -ENOMEM;
237
238	idev = axp20x_pek->input;
239
240	idev->name = "axp20x-pek";
241	idev->phys = "m1kbd/input2";
242	idev->dev.parent = &pdev->dev;
243
244	input_set_capability(idev, EV_KEY, KEY_POWER);
245
246	input_set_drvdata(idev, axp20x_pek);
247
248	error = input_register_device(idev);
249	if (error) {
250		dev_err(&pdev->dev, "Can't register input device: %d\n",
251			error);
252		return error;
253	}
254
255	return 0;
256}
257
258#ifdef CONFIG_ACPI
259static bool axp20x_pek_should_register_input(struct axp20x_pek *axp20x_pek,
260					     struct platform_device *pdev)
261{
262	unsigned long long hrv = 0;
263	acpi_status status;
264
265	if (IS_ENABLED(CONFIG_INPUT_SOC_BUTTON_ARRAY) &&
266	    axp20x_pek->axp20x->variant == AXP288_ID) {
267		status = acpi_evaluate_integer(ACPI_HANDLE(pdev->dev.parent),
268					       "_HRV", NULL, &hrv);
269		if (ACPI_FAILURE(status))
270			dev_err(&pdev->dev, "Failed to get PMIC hardware revision\n");
271
272		/*
273		 * On Cherry Trail platforms (hrv == 3), do not register the
274		 * input device if there is an "INTCFD9" or "ACPI0011" gpio
275		 * button ACPI device, as that handles the power button too,
276		 * and otherwise we end up reporting all presses twice.
277		 */
278		if (hrv == 3 && (acpi_dev_present("INTCFD9", NULL, -1) ||
279				 acpi_dev_present("ACPI0011", NULL, -1)))
280			return false;
281
282	}
283
284	return true;
285}
286#else
287static bool axp20x_pek_should_register_input(struct axp20x_pek *axp20x_pek,
288					     struct platform_device *pdev)
289{
290	return true;
291}
292#endif
293
294static int axp20x_pek_probe(struct platform_device *pdev)
295{
296	struct axp20x_pek *axp20x_pek;
297	const struct platform_device_id *match = platform_get_device_id(pdev);
298	int error;
299
300	if (!match) {
301		dev_err(&pdev->dev, "Failed to get platform_device_id\n");
302		return -EINVAL;
303	}
304
305	axp20x_pek = devm_kzalloc(&pdev->dev, sizeof(struct axp20x_pek),
306				  GFP_KERNEL);
307	if (!axp20x_pek)
308		return -ENOMEM;
309
310	axp20x_pek->axp20x = dev_get_drvdata(pdev->dev.parent);
311
312	axp20x_pek->irq_dbr = platform_get_irq_byname(pdev, "PEK_DBR");
313	if (axp20x_pek->irq_dbr < 0)
314		return axp20x_pek->irq_dbr;
315	axp20x_pek->irq_dbr = regmap_irq_get_virq(
316			axp20x_pek->axp20x->regmap_irqc, axp20x_pek->irq_dbr);
317
318	axp20x_pek->irq_dbf = platform_get_irq_byname(pdev, "PEK_DBF");
319	if (axp20x_pek->irq_dbf < 0)
320		return axp20x_pek->irq_dbf;
321	axp20x_pek->irq_dbf = regmap_irq_get_virq(
322			axp20x_pek->axp20x->regmap_irqc, axp20x_pek->irq_dbf);
323
324	if (axp20x_pek_should_register_input(axp20x_pek, pdev)) {
325		error = axp20x_pek_probe_input_device(axp20x_pek, pdev);
326		if (error)
327			return error;
328	}
329
330	axp20x_pek->info = (struct axp20x_info *)match->driver_data;
331
332	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbr,
333					     axp20x_pek_irq, 0,
334					     "axp20x-pek-dbr", axp20x_pek);
335	if (error < 0) {
336		dev_err(&pdev->dev, "Failed to request dbr IRQ#%d: %d\n",
337			axp20x_pek->irq_dbr, error);
338		return error;
339	}
340
341	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbf,
342					  axp20x_pek_irq, 0,
343					  "axp20x-pek-dbf", axp20x_pek);
344	if (error < 0) {
345		dev_err(&pdev->dev, "Failed to request dbf IRQ#%d: %d\n",
346			axp20x_pek->irq_dbf, error);
347		return error;
348	}
349
350	device_init_wakeup(&pdev->dev, true);
351
352	platform_set_drvdata(pdev, axp20x_pek);
353
354	return 0;
355}
356
357static int __maybe_unused axp20x_pek_suspend(struct device *dev)
358{
359	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
360
361	/*
362	 * As nested threaded IRQs are not automatically disabled during
363	 * suspend, we must explicitly disable non-wakeup IRQs.
364	 */
365	if (device_may_wakeup(dev)) {
366		enable_irq_wake(axp20x_pek->irq_dbf);
367		enable_irq_wake(axp20x_pek->irq_dbr);
368	} else {
369		disable_irq(axp20x_pek->irq_dbf);
370		disable_irq(axp20x_pek->irq_dbr);
371	}
372
373	return 0;
374}
375
376static int __maybe_unused axp20x_pek_resume(struct device *dev)
377{
378	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
379
380	if (device_may_wakeup(dev)) {
381		disable_irq_wake(axp20x_pek->irq_dbf);
382		disable_irq_wake(axp20x_pek->irq_dbr);
383	} else {
384		enable_irq(axp20x_pek->irq_dbf);
385		enable_irq(axp20x_pek->irq_dbr);
386	}
387
388	return 0;
389}
390
391static int __maybe_unused axp20x_pek_resume_noirq(struct device *dev)
392{
393	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
394
395	if (axp20x_pek->axp20x->variant != AXP288_ID)
396		return 0;
397
398	/*
399	 * Clear interrupts from button presses during suspend, to avoid
400	 * a wakeup power-button press getting reported to userspace.
401	 */
402	regmap_write(axp20x_pek->axp20x->regmap,
403		     AXP20X_IRQ1_STATE + AXP288_IRQ_POKN / 8,
404		     BIT(AXP288_IRQ_POKN % 8));
405
406	return 0;
407}
408
409static const struct dev_pm_ops axp20x_pek_pm_ops = {
410	SET_SYSTEM_SLEEP_PM_OPS(axp20x_pek_suspend, axp20x_pek_resume)
411#ifdef CONFIG_PM_SLEEP
412	.resume_noirq = axp20x_pek_resume_noirq,
413#endif
414};
415
416static const struct platform_device_id axp_pek_id_match[] = {
417	{
418		.name = "axp20x-pek",
419		.driver_data = (kernel_ulong_t)&axp20x_info,
420	},
421	{
422		.name = "axp221-pek",
423		.driver_data = (kernel_ulong_t)&axp221_info,
424	},
425	{ /* sentinel */ }
426};
427MODULE_DEVICE_TABLE(platform, axp_pek_id_match);
428
429static struct platform_driver axp20x_pek_driver = {
430	.probe		= axp20x_pek_probe,
431	.id_table	= axp_pek_id_match,
432	.driver		= {
433		.name		= "axp20x-pek",
434		.pm		= &axp20x_pek_pm_ops,
435		.dev_groups	= axp20x_groups,
436	},
437};
438module_platform_driver(axp20x_pek_driver);
439
440MODULE_DESCRIPTION("axp20x Power Button");
441MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
442MODULE_LICENSE("GPL");
443