1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * CPCAP Power Button Input Driver
4  *
5  * Copyright (C) 2017 Sebastian Reichel <sre@kernel.org>
6  */
7 
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/kernel.h>
11 #include <linux/errno.h>
12 #include <linux/input.h>
13 #include <linux/interrupt.h>
14 #include <linux/regmap.h>
15 #include <linux/of.h>
16 #include <linux/platform_device.h>
17 #include <linux/mfd/motorola-cpcap.h>
18 
19 #define CPCAP_IRQ_ON 23
20 #define CPCAP_IRQ_ON_BITMASK (1 << (CPCAP_IRQ_ON % 16))
21 
22 struct cpcap_power_button {
23 	struct regmap *regmap;
24 	struct input_dev *idev;
25 	struct device *dev;
26 };
27 
28 static irqreturn_t powerbutton_irq(int irq, void *_button)
29 {
30 	struct cpcap_power_button *button = _button;
31 	int val;
32 
33 	val = cpcap_sense_virq(button->regmap, irq);
34 	if (val < 0) {
35 		dev_err(button->dev, "irq read failed: %d", val);
36 		return IRQ_HANDLED;
37 	}
38 
39 	pm_wakeup_event(button->dev, 0);
40 	input_report_key(button->idev, KEY_POWER, val);
41 	input_sync(button->idev);
42 
43 	return IRQ_HANDLED;
44 }
45 
46 static int cpcap_power_button_probe(struct platform_device *pdev)
47 {
48 	struct cpcap_power_button *button;
49 	int irq;
50 	int err;
51 
52 	irq = platform_get_irq(pdev, 0);
53 	if (irq < 0)
54 		return irq;
55 
56 	button = devm_kmalloc(&pdev->dev, sizeof(*button), GFP_KERNEL);
57 	if (!button)
58 		return -ENOMEM;
59 
60 	button->idev = devm_input_allocate_device(&pdev->dev);
61 	if (!button->idev)
62 		return -ENOMEM;
63 
64 	button->regmap = dev_get_regmap(pdev->dev.parent, NULL);
65 	if (!button->regmap)
66 		return -ENODEV;
67 
68 	button->dev = &pdev->dev;
69 
70 	button->idev->name = "cpcap-pwrbutton";
71 	button->idev->phys = "cpcap-pwrbutton/input0";
72 	input_set_capability(button->idev, EV_KEY, KEY_POWER);
73 
74 	err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
75 		powerbutton_irq, IRQF_ONESHOT, "cpcap_pwrbutton", button);
76 	if (err < 0) {
77 		dev_err(&pdev->dev, "IRQ request failed: %d\n", err);
78 		return err;
79 	}
80 
81 	err = input_register_device(button->idev);
82 	if (err) {
83 		dev_err(&pdev->dev, "Input register failed: %d\n", err);
84 		return err;
85 	}
86 
87 	device_init_wakeup(&pdev->dev, true);
88 
89 	return 0;
90 }
91 
92 #ifdef CONFIG_OF
93 static const struct of_device_id cpcap_pwrbutton_dt_match_table[] = {
94 	{ .compatible = "motorola,cpcap-pwrbutton" },
95 	{},
96 };
97 MODULE_DEVICE_TABLE(of, cpcap_pwrbutton_dt_match_table);
98 #endif
99 
100 static struct platform_driver cpcap_power_button_driver = {
101 	.probe		= cpcap_power_button_probe,
102 	.driver		= {
103 		.name	= "cpcap-pwrbutton",
104 		.of_match_table = of_match_ptr(cpcap_pwrbutton_dt_match_table),
105 	},
106 };
107 module_platform_driver(cpcap_power_button_driver);
108 
109 MODULE_ALIAS("platform:cpcap-pwrbutton");
110 MODULE_DESCRIPTION("CPCAP Power Button");
111 MODULE_LICENSE("GPL");
112 MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
113