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_data/x86/soc.h>
26 #include <linux/platform_device.h>
27 #include <linux/regmap.h>
28 #include <linux/slab.h>
29 
30 #define AXP20X_PEK_STARTUP_MASK		(0xc0)
31 #define AXP20X_PEK_SHUTDOWN_MASK	(0x03)
32 
33 struct axp20x_info {
34 	const struct axp20x_time *startup_time;
35 	unsigned int startup_mask;
36 	const struct axp20x_time *shutdown_time;
37 	unsigned int shutdown_mask;
38 };
39 
40 struct axp20x_pek {
41 	struct axp20x_dev *axp20x;
42 	struct input_dev *input;
43 	struct axp20x_info *info;
44 	int irq_dbr;
45 	int irq_dbf;
46 };
47 
48 struct axp20x_time {
49 	unsigned int time;
50 	unsigned int idx;
51 };
52 
53 static const struct axp20x_time startup_time[] = {
54 	{ .time = 128,  .idx = 0 },
55 	{ .time = 1000, .idx = 2 },
56 	{ .time = 3000, .idx = 1 },
57 	{ .time = 2000, .idx = 3 },
58 };
59 
60 static const struct axp20x_time axp221_startup_time[] = {
61 	{ .time = 128,  .idx = 0 },
62 	{ .time = 1000, .idx = 1 },
63 	{ .time = 2000, .idx = 2 },
64 	{ .time = 3000, .idx = 3 },
65 };
66 
67 static const struct axp20x_time shutdown_time[] = {
68 	{ .time = 4000,  .idx = 0 },
69 	{ .time = 6000,  .idx = 1 },
70 	{ .time = 8000,  .idx = 2 },
71 	{ .time = 10000, .idx = 3 },
72 };
73 
74 static const struct axp20x_info axp20x_info = {
75 	.startup_time = startup_time,
76 	.startup_mask = AXP20X_PEK_STARTUP_MASK,
77 	.shutdown_time = shutdown_time,
78 	.shutdown_mask = AXP20X_PEK_SHUTDOWN_MASK,
79 };
80 
81 static const struct axp20x_info axp221_info = {
82 	.startup_time = axp221_startup_time,
83 	.startup_mask = AXP20X_PEK_STARTUP_MASK,
84 	.shutdown_time = shutdown_time,
85 	.shutdown_mask = AXP20X_PEK_SHUTDOWN_MASK,
86 };
87 
axp20x_show_attr(struct device * dev,const struct axp20x_time * time,unsigned int mask,char * buf)88 static ssize_t axp20x_show_attr(struct device *dev,
89 				const struct axp20x_time *time,
90 				unsigned int mask, char *buf)
91 {
92 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
93 	unsigned int val;
94 	int ret, i;
95 
96 	ret = regmap_read(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY, &val);
97 	if (ret != 0)
98 		return ret;
99 
100 	val &= mask;
101 	val >>= ffs(mask) - 1;
102 
103 	for (i = 0; i < 4; i++)
104 		if (val == time[i].idx)
105 			val = time[i].time;
106 
107 	return sprintf(buf, "%u\n", val);
108 }
109 
axp20x_show_attr_startup(struct device * dev,struct device_attribute * attr,char * buf)110 static ssize_t axp20x_show_attr_startup(struct device *dev,
111 					struct device_attribute *attr,
112 					char *buf)
113 {
114 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
115 
116 	return axp20x_show_attr(dev, axp20x_pek->info->startup_time,
117 				axp20x_pek->info->startup_mask, buf);
118 }
119 
axp20x_show_attr_shutdown(struct device * dev,struct device_attribute * attr,char * buf)120 static ssize_t axp20x_show_attr_shutdown(struct device *dev,
121 					 struct device_attribute *attr,
122 					 char *buf)
123 {
124 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
125 
126 	return axp20x_show_attr(dev, axp20x_pek->info->shutdown_time,
127 				axp20x_pek->info->shutdown_mask, buf);
128 }
129 
axp20x_store_attr(struct device * dev,const struct axp20x_time * time,unsigned int mask,const char * buf,size_t count)130 static ssize_t axp20x_store_attr(struct device *dev,
131 				 const struct axp20x_time *time,
132 				 unsigned int mask, const char *buf,
133 				 size_t count)
134 {
135 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
136 	char val_str[20];
137 	size_t len;
138 	int ret, i;
139 	unsigned int val, idx = 0;
140 	unsigned int best_err = UINT_MAX;
141 
142 	val_str[sizeof(val_str) - 1] = '\0';
143 	strncpy(val_str, buf, sizeof(val_str) - 1);
144 	len = strlen(val_str);
145 
146 	if (len && val_str[len - 1] == '\n')
147 		val_str[len - 1] = '\0';
148 
149 	ret = kstrtouint(val_str, 10, &val);
150 	if (ret)
151 		return ret;
152 
153 	for (i = 3; i >= 0; i--) {
154 		unsigned int err;
155 
156 		err = abs(time[i].time - val);
157 		if (err < best_err) {
158 			best_err = err;
159 			idx = time[i].idx;
160 		}
161 
162 		if (!err)
163 			break;
164 	}
165 
166 	idx <<= ffs(mask) - 1;
167 	ret = regmap_update_bits(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY,
168 				 mask, idx);
169 	if (ret != 0)
170 		return -EINVAL;
171 
172 	return count;
173 }
174 
axp20x_store_attr_startup(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)175 static ssize_t axp20x_store_attr_startup(struct device *dev,
176 					 struct device_attribute *attr,
177 					 const char *buf, size_t count)
178 {
179 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
180 
181 	return axp20x_store_attr(dev, axp20x_pek->info->startup_time,
182 				 axp20x_pek->info->startup_mask, buf, count);
183 }
184 
axp20x_store_attr_shutdown(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)185 static ssize_t axp20x_store_attr_shutdown(struct device *dev,
186 					  struct device_attribute *attr,
187 					  const char *buf, size_t count)
188 {
189 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
190 
191 	return axp20x_store_attr(dev, axp20x_pek->info->shutdown_time,
192 				 axp20x_pek->info->shutdown_mask, buf, count);
193 }
194 
195 static DEVICE_ATTR(startup, 0644, axp20x_show_attr_startup,
196 		   axp20x_store_attr_startup);
197 static DEVICE_ATTR(shutdown, 0644, axp20x_show_attr_shutdown,
198 		   axp20x_store_attr_shutdown);
199 
200 static struct attribute *axp20x_attrs[] = {
201 	&dev_attr_startup.attr,
202 	&dev_attr_shutdown.attr,
203 	NULL,
204 };
205 ATTRIBUTE_GROUPS(axp20x);
206 
axp20x_pek_irq(int irq,void * pwr)207 static irqreturn_t axp20x_pek_irq(int irq, void *pwr)
208 {
209 	struct input_dev *idev = pwr;
210 	struct axp20x_pek *axp20x_pek = input_get_drvdata(idev);
211 
212 	/*
213 	 * The power-button is connected to ground so a falling edge (dbf)
214 	 * means it is pressed.
215 	 */
216 	if (irq == axp20x_pek->irq_dbf)
217 		input_report_key(idev, KEY_POWER, true);
218 	else if (irq == axp20x_pek->irq_dbr)
219 		input_report_key(idev, KEY_POWER, false);
220 
221 	input_sync(idev);
222 
223 	return IRQ_HANDLED;
224 }
225 
axp20x_pek_probe_input_device(struct axp20x_pek * axp20x_pek,struct platform_device * pdev)226 static int axp20x_pek_probe_input_device(struct axp20x_pek *axp20x_pek,
227 					 struct platform_device *pdev)
228 {
229 	struct axp20x_dev *axp20x = axp20x_pek->axp20x;
230 	struct input_dev *idev;
231 	int error;
232 
233 	axp20x_pek->irq_dbr = platform_get_irq_byname(pdev, "PEK_DBR");
234 	if (axp20x_pek->irq_dbr < 0)
235 		return axp20x_pek->irq_dbr;
236 	axp20x_pek->irq_dbr = regmap_irq_get_virq(axp20x->regmap_irqc,
237 						  axp20x_pek->irq_dbr);
238 
239 	axp20x_pek->irq_dbf = platform_get_irq_byname(pdev, "PEK_DBF");
240 	if (axp20x_pek->irq_dbf < 0)
241 		return axp20x_pek->irq_dbf;
242 	axp20x_pek->irq_dbf = regmap_irq_get_virq(axp20x->regmap_irqc,
243 						  axp20x_pek->irq_dbf);
244 
245 	axp20x_pek->input = devm_input_allocate_device(&pdev->dev);
246 	if (!axp20x_pek->input)
247 		return -ENOMEM;
248 
249 	idev = axp20x_pek->input;
250 
251 	idev->name = "axp20x-pek";
252 	idev->phys = "m1kbd/input2";
253 	idev->dev.parent = &pdev->dev;
254 
255 	input_set_capability(idev, EV_KEY, KEY_POWER);
256 
257 	input_set_drvdata(idev, axp20x_pek);
258 
259 	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbr,
260 					     axp20x_pek_irq, 0,
261 					     "axp20x-pek-dbr", idev);
262 	if (error < 0) {
263 		dev_err(&pdev->dev, "Failed to request dbr IRQ#%d: %d\n",
264 			axp20x_pek->irq_dbr, error);
265 		return error;
266 	}
267 
268 	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbf,
269 					  axp20x_pek_irq, 0,
270 					  "axp20x-pek-dbf", idev);
271 	if (error < 0) {
272 		dev_err(&pdev->dev, "Failed to request dbf IRQ#%d: %d\n",
273 			axp20x_pek->irq_dbf, error);
274 		return error;
275 	}
276 
277 	error = input_register_device(idev);
278 	if (error) {
279 		dev_err(&pdev->dev, "Can't register input device: %d\n",
280 			error);
281 		return error;
282 	}
283 
284 	device_init_wakeup(&pdev->dev, true);
285 
286 	return 0;
287 }
288 
axp20x_pek_should_register_input(struct axp20x_pek * axp20x_pek)289 static bool axp20x_pek_should_register_input(struct axp20x_pek *axp20x_pek)
290 {
291 	if (IS_ENABLED(CONFIG_INPUT_SOC_BUTTON_ARRAY) &&
292 	    axp20x_pek->axp20x->variant == AXP288_ID) {
293 		/*
294 		 * On Cherry Trail platforms (hrv == 3), do not register the
295 		 * input device if there is an "INTCFD9" or "ACPI0011" gpio
296 		 * button ACPI device, as that handles the power button too,
297 		 * and otherwise we end up reporting all presses twice.
298 		 */
299 		if (soc_intel_is_cht() &&
300 				(acpi_dev_present("INTCFD9", NULL, -1) ||
301 				 acpi_dev_present("ACPI0011", NULL, -1)))
302 			return false;
303 	}
304 
305 	return true;
306 }
307 
axp20x_pek_probe(struct platform_device * pdev)308 static int axp20x_pek_probe(struct platform_device *pdev)
309 {
310 	struct axp20x_pek *axp20x_pek;
311 	const struct platform_device_id *match = platform_get_device_id(pdev);
312 	int error;
313 
314 	if (!match) {
315 		dev_err(&pdev->dev, "Failed to get platform_device_id\n");
316 		return -EINVAL;
317 	}
318 
319 	axp20x_pek = devm_kzalloc(&pdev->dev, sizeof(struct axp20x_pek),
320 				  GFP_KERNEL);
321 	if (!axp20x_pek)
322 		return -ENOMEM;
323 
324 	axp20x_pek->axp20x = dev_get_drvdata(pdev->dev.parent);
325 
326 	if (axp20x_pek_should_register_input(axp20x_pek)) {
327 		error = axp20x_pek_probe_input_device(axp20x_pek, pdev);
328 		if (error)
329 			return error;
330 	}
331 
332 	axp20x_pek->info = (struct axp20x_info *)match->driver_data;
333 
334 	platform_set_drvdata(pdev, axp20x_pek);
335 
336 	return 0;
337 }
338 
axp20x_pek_suspend(struct device * dev)339 static int axp20x_pek_suspend(struct device *dev)
340 {
341 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
342 
343 	/*
344 	 * As nested threaded IRQs are not automatically disabled during
345 	 * suspend, we must explicitly disable non-wakeup IRQs.
346 	 */
347 	if (device_may_wakeup(dev)) {
348 		enable_irq_wake(axp20x_pek->irq_dbf);
349 		enable_irq_wake(axp20x_pek->irq_dbr);
350 	} else {
351 		disable_irq(axp20x_pek->irq_dbf);
352 		disable_irq(axp20x_pek->irq_dbr);
353 	}
354 
355 	return 0;
356 }
357 
axp20x_pek_resume(struct device * dev)358 static int axp20x_pek_resume(struct device *dev)
359 {
360 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
361 
362 	if (device_may_wakeup(dev)) {
363 		disable_irq_wake(axp20x_pek->irq_dbf);
364 		disable_irq_wake(axp20x_pek->irq_dbr);
365 	} else {
366 		enable_irq(axp20x_pek->irq_dbf);
367 		enable_irq(axp20x_pek->irq_dbr);
368 	}
369 
370 	return 0;
371 }
372 
axp20x_pek_resume_noirq(struct device * dev)373 static int __maybe_unused axp20x_pek_resume_noirq(struct device *dev)
374 {
375 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
376 
377 	if (axp20x_pek->axp20x->variant != AXP288_ID)
378 		return 0;
379 
380 	/*
381 	 * Clear interrupts from button presses during suspend, to avoid
382 	 * a wakeup power-button press getting reported to userspace.
383 	 */
384 	regmap_write(axp20x_pek->axp20x->regmap,
385 		     AXP20X_IRQ1_STATE + AXP288_IRQ_POKN / 8,
386 		     BIT(AXP288_IRQ_POKN % 8));
387 
388 	return 0;
389 }
390 
391 static const struct dev_pm_ops axp20x_pek_pm_ops = {
392 	SYSTEM_SLEEP_PM_OPS(axp20x_pek_suspend, axp20x_pek_resume)
393 	.resume_noirq = pm_sleep_ptr(axp20x_pek_resume_noirq),
394 };
395 
396 static const struct platform_device_id axp_pek_id_match[] = {
397 	{
398 		.name = "axp20x-pek",
399 		.driver_data = (kernel_ulong_t)&axp20x_info,
400 	},
401 	{
402 		.name = "axp221-pek",
403 		.driver_data = (kernel_ulong_t)&axp221_info,
404 	},
405 	{ /* sentinel */ }
406 };
407 MODULE_DEVICE_TABLE(platform, axp_pek_id_match);
408 
409 static struct platform_driver axp20x_pek_driver = {
410 	.probe		= axp20x_pek_probe,
411 	.id_table	= axp_pek_id_match,
412 	.driver		= {
413 		.name		= "axp20x-pek",
414 		.pm		= pm_sleep_ptr(&axp20x_pek_pm_ops),
415 		.dev_groups	= axp20x_groups,
416 	},
417 };
418 module_platform_driver(axp20x_pek_driver);
419 
420 MODULE_DESCRIPTION("axp20x Power Button");
421 MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
422 MODULE_LICENSE("GPL");
423