xref: /openbmc/linux/drivers/input/misc/axp20x-pek.c (revision a36954f5)
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_pek {
33 	struct axp20x_dev *axp20x;
34 	struct input_dev *input;
35 	int irq_dbr;
36 	int irq_dbf;
37 };
38 
39 struct axp20x_time {
40 	unsigned int time;
41 	unsigned int idx;
42 };
43 
44 static const struct axp20x_time startup_time[] = {
45 	{ .time = 128,  .idx = 0 },
46 	{ .time = 1000, .idx = 2 },
47 	{ .time = 3000, .idx = 1 },
48 	{ .time = 2000, .idx = 3 },
49 };
50 
51 static const struct axp20x_time shutdown_time[] = {
52 	{ .time = 4000,  .idx = 0 },
53 	{ .time = 6000,  .idx = 1 },
54 	{ .time = 8000,  .idx = 2 },
55 	{ .time = 10000, .idx = 3 },
56 };
57 
58 struct axp20x_pek_ext_attr {
59 	const struct axp20x_time *p_time;
60 	unsigned int mask;
61 };
62 
63 static struct axp20x_pek_ext_attr axp20x_pek_startup_ext_attr = {
64 	.p_time	= startup_time,
65 	.mask	= AXP20X_PEK_STARTUP_MASK,
66 };
67 
68 static struct axp20x_pek_ext_attr axp20x_pek_shutdown_ext_attr = {
69 	.p_time	= shutdown_time,
70 	.mask	= AXP20X_PEK_SHUTDOWN_MASK,
71 };
72 
73 static struct axp20x_pek_ext_attr *get_axp_ext_attr(struct device_attribute *attr)
74 {
75 	return container_of(attr, struct dev_ext_attribute, attr)->var;
76 }
77 
78 static ssize_t axp20x_show_ext_attr(struct device *dev,
79 				    struct device_attribute *attr, char *buf)
80 {
81 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
82 	struct axp20x_pek_ext_attr *axp20x_ea = get_axp_ext_attr(attr);
83 	unsigned int val;
84 	int ret, i;
85 
86 	ret = regmap_read(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY, &val);
87 	if (ret != 0)
88 		return ret;
89 
90 	val &= axp20x_ea->mask;
91 	val >>= ffs(axp20x_ea->mask) - 1;
92 
93 	for (i = 0; i < 4; i++)
94 		if (val == axp20x_ea->p_time[i].idx)
95 			val = axp20x_ea->p_time[i].time;
96 
97 	return sprintf(buf, "%u\n", val);
98 }
99 
100 static ssize_t axp20x_store_ext_attr(struct device *dev,
101 				     struct device_attribute *attr,
102 				     const char *buf, size_t count)
103 {
104 	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
105 	struct axp20x_pek_ext_attr *axp20x_ea = get_axp_ext_attr(attr);
106 	char val_str[20];
107 	size_t len;
108 	int ret, i;
109 	unsigned int val, idx = 0;
110 	unsigned int best_err = UINT_MAX;
111 
112 	val_str[sizeof(val_str) - 1] = '\0';
113 	strncpy(val_str, buf, sizeof(val_str) - 1);
114 	len = strlen(val_str);
115 
116 	if (len && val_str[len - 1] == '\n')
117 		val_str[len - 1] = '\0';
118 
119 	ret = kstrtouint(val_str, 10, &val);
120 	if (ret)
121 		return ret;
122 
123 	for (i = 3; i >= 0; i--) {
124 		unsigned int err;
125 
126 		err = abs(axp20x_ea->p_time[i].time - val);
127 		if (err < best_err) {
128 			best_err = err;
129 			idx = axp20x_ea->p_time[i].idx;
130 		}
131 
132 		if (!err)
133 			break;
134 	}
135 
136 	idx <<= ffs(axp20x_ea->mask) - 1;
137 	ret = regmap_update_bits(axp20x_pek->axp20x->regmap,
138 				 AXP20X_PEK_KEY,
139 				 axp20x_ea->mask, idx);
140 	if (ret != 0)
141 		return -EINVAL;
142 
143 	return count;
144 }
145 
146 static struct dev_ext_attribute axp20x_dev_attr_startup = {
147 	.attr	= __ATTR(startup, 0644, axp20x_show_ext_attr, axp20x_store_ext_attr),
148 	.var	= &axp20x_pek_startup_ext_attr,
149 };
150 
151 static struct dev_ext_attribute axp20x_dev_attr_shutdown = {
152 	.attr	= __ATTR(shutdown, 0644, axp20x_show_ext_attr, axp20x_store_ext_attr),
153 	.var	= &axp20x_pek_shutdown_ext_attr,
154 };
155 
156 static struct attribute *axp20x_attributes[] = {
157 	&axp20x_dev_attr_startup.attr.attr,
158 	&axp20x_dev_attr_shutdown.attr.attr,
159 	NULL,
160 };
161 
162 static const struct attribute_group axp20x_attribute_group = {
163 	.attrs = axp20x_attributes,
164 };
165 
166 static irqreturn_t axp20x_pek_irq(int irq, void *pwr)
167 {
168 	struct input_dev *idev = pwr;
169 	struct axp20x_pek *axp20x_pek = input_get_drvdata(idev);
170 
171 	/*
172 	 * The power-button is connected to ground so a falling edge (dbf)
173 	 * means it is pressed.
174 	 */
175 	if (irq == axp20x_pek->irq_dbf)
176 		input_report_key(idev, KEY_POWER, true);
177 	else if (irq == axp20x_pek->irq_dbr)
178 		input_report_key(idev, KEY_POWER, false);
179 
180 	input_sync(idev);
181 
182 	return IRQ_HANDLED;
183 }
184 
185 static void axp20x_remove_sysfs_group(void *_data)
186 {
187 	struct device *dev = _data;
188 
189 	sysfs_remove_group(&dev->kobj, &axp20x_attribute_group);
190 }
191 
192 static int axp20x_pek_probe_input_device(struct axp20x_pek *axp20x_pek,
193 					 struct platform_device *pdev)
194 {
195 	struct axp20x_dev *axp20x = axp20x_pek->axp20x;
196 	struct input_dev *idev;
197 	int error;
198 
199 	axp20x_pek->irq_dbr = platform_get_irq_byname(pdev, "PEK_DBR");
200 	if (axp20x_pek->irq_dbr < 0) {
201 		dev_err(&pdev->dev, "No IRQ for PEK_DBR, error=%d\n",
202 				axp20x_pek->irq_dbr);
203 		return axp20x_pek->irq_dbr;
204 	}
205 	axp20x_pek->irq_dbr = regmap_irq_get_virq(axp20x->regmap_irqc,
206 						  axp20x_pek->irq_dbr);
207 
208 	axp20x_pek->irq_dbf = platform_get_irq_byname(pdev, "PEK_DBF");
209 	if (axp20x_pek->irq_dbf < 0) {
210 		dev_err(&pdev->dev, "No IRQ for PEK_DBF, error=%d\n",
211 				axp20x_pek->irq_dbf);
212 		return axp20x_pek->irq_dbf;
213 	}
214 	axp20x_pek->irq_dbf = regmap_irq_get_virq(axp20x->regmap_irqc,
215 						  axp20x_pek->irq_dbf);
216 
217 	axp20x_pek->input = devm_input_allocate_device(&pdev->dev);
218 	if (!axp20x_pek->input)
219 		return -ENOMEM;
220 
221 	idev = axp20x_pek->input;
222 
223 	idev->name = "axp20x-pek";
224 	idev->phys = "m1kbd/input2";
225 	idev->dev.parent = &pdev->dev;
226 
227 	input_set_capability(idev, EV_KEY, KEY_POWER);
228 
229 	input_set_drvdata(idev, axp20x_pek);
230 
231 	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbr,
232 					     axp20x_pek_irq, 0,
233 					     "axp20x-pek-dbr", idev);
234 	if (error < 0) {
235 		dev_err(&pdev->dev, "Failed to request dbr IRQ#%d: %d\n",
236 			axp20x_pek->irq_dbr, error);
237 		return error;
238 	}
239 
240 	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbf,
241 					  axp20x_pek_irq, 0,
242 					  "axp20x-pek-dbf", idev);
243 	if (error < 0) {
244 		dev_err(&pdev->dev, "Failed to request dbf IRQ#%d: %d\n",
245 			axp20x_pek->irq_dbf, error);
246 		return error;
247 	}
248 
249 	error = input_register_device(idev);
250 	if (error) {
251 		dev_err(&pdev->dev, "Can't register input device: %d\n",
252 			error);
253 		return error;
254 	}
255 
256 	return 0;
257 }
258 
259 static int axp20x_pek_probe(struct platform_device *pdev)
260 {
261 	struct axp20x_pek *axp20x_pek;
262 	int error;
263 
264 	axp20x_pek = devm_kzalloc(&pdev->dev, sizeof(struct axp20x_pek),
265 				  GFP_KERNEL);
266 	if (!axp20x_pek)
267 		return -ENOMEM;
268 
269 	axp20x_pek->axp20x = dev_get_drvdata(pdev->dev.parent);
270 
271 	/*
272 	 * Do not register the input device if there is an "INTCFD9"
273 	 * gpio button ACPI device, that handles the power button too,
274 	 * and otherwise we end up reporting all presses twice.
275 	 */
276 	if (!acpi_dev_found("INTCFD9") ||
277 	    !IS_ENABLED(CONFIG_INPUT_SOC_BUTTON_ARRAY)) {
278 		error = axp20x_pek_probe_input_device(axp20x_pek, pdev);
279 		if (error)
280 			return error;
281 	}
282 
283 	error = sysfs_create_group(&pdev->dev.kobj, &axp20x_attribute_group);
284 	if (error) {
285 		dev_err(&pdev->dev, "Failed to create sysfs attributes: %d\n",
286 			error);
287 		return error;
288 	}
289 
290 	error = devm_add_action(&pdev->dev,
291 				axp20x_remove_sysfs_group, &pdev->dev);
292 	if (error) {
293 		axp20x_remove_sysfs_group(&pdev->dev);
294 		dev_err(&pdev->dev, "Failed to add sysfs cleanup action: %d\n",
295 			error);
296 		return error;
297 	}
298 
299 	platform_set_drvdata(pdev, axp20x_pek);
300 
301 	return 0;
302 }
303 
304 static struct platform_driver axp20x_pek_driver = {
305 	.probe		= axp20x_pek_probe,
306 	.driver		= {
307 		.name		= "axp20x-pek",
308 	},
309 };
310 module_platform_driver(axp20x_pek_driver);
311 
312 MODULE_DESCRIPTION("axp20x Power Button");
313 MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
314 MODULE_LICENSE("GPL");
315 MODULE_ALIAS("platform:axp20x-pek");
316