xref: /openbmc/linux/drivers/input/misc/axp20x-pek.c (revision b4e18b29)
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 
32 struct 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 
39 struct 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 
47 struct axp20x_time {
48 	unsigned int time;
49 	unsigned int idx;
50 };
51 
52 static 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 
59 static 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 
66 static 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 
73 static 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 
80 static 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 
87 static 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 
109 static 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 
119 static 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 
129 static 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 
174 static 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 
184 static 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 
194 static DEVICE_ATTR(startup, 0644, axp20x_show_attr_startup,
195 		   axp20x_store_attr_startup);
196 static DEVICE_ATTR(shutdown, 0644, axp20x_show_attr_shutdown,
197 		   axp20x_store_attr_shutdown);
198 
199 static struct attribute *axp20x_attrs[] = {
200 	&dev_attr_startup.attr,
201 	&dev_attr_shutdown.attr,
202 	NULL,
203 };
204 ATTRIBUTE_GROUPS(axp20x);
205 
206 static 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 
228 static 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
259 static 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
287 static bool axp20x_pek_should_register_input(struct axp20x_pek *axp20x_pek,
288 					     struct platform_device *pdev)
289 {
290 	return true;
291 }
292 #endif
293 
294 static 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 
357 static 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 
376 static 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 
391 static 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 
409 static 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 
416 static 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 };
427 MODULE_DEVICE_TABLE(platform, axp_pek_id_match);
428 
429 static 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 };
438 module_platform_driver(axp20x_pek_driver);
439 
440 MODULE_DESCRIPTION("axp20x Power Button");
441 MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
442 MODULE_LICENSE("GPL");
443