xref: /openbmc/linux/drivers/input/misc/pcap_keys.c (revision 63dc02bd)
1 /*
2  *  Input driver for PCAP events:
3  *   * Power key
4  *   * Headphone button
5  *
6  *  Copyright (c) 2008,2009 Ilya Petrov <ilya.muromec@gmail.com>
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License version 2 as
10  *  published by the Free Software Foundation.
11  *
12  */
13 
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/platform_device.h>
18 #include <linux/input.h>
19 #include <linux/mfd/ezx-pcap.h>
20 #include <linux/slab.h>
21 
22 struct pcap_keys {
23 	struct pcap_chip *pcap;
24 	struct input_dev *input;
25 };
26 
27 /* PCAP2 interrupts us on keypress */
28 static irqreturn_t pcap_keys_handler(int irq, void *_pcap_keys)
29 {
30 	struct pcap_keys *pcap_keys = _pcap_keys;
31 	int pirq = irq_to_pcap(pcap_keys->pcap, irq);
32 	u32 pstat;
33 
34 	ezx_pcap_read(pcap_keys->pcap, PCAP_REG_PSTAT, &pstat);
35 	pstat &= 1 << pirq;
36 
37 	switch (pirq) {
38 	case PCAP_IRQ_ONOFF:
39 		input_report_key(pcap_keys->input, KEY_POWER, !pstat);
40 		break;
41 	case PCAP_IRQ_MIC:
42 		input_report_key(pcap_keys->input, KEY_HP, !pstat);
43 		break;
44 	}
45 
46 	input_sync(pcap_keys->input);
47 
48 	return IRQ_HANDLED;
49 }
50 
51 static int __devinit pcap_keys_probe(struct platform_device *pdev)
52 {
53 	int err = -ENOMEM;
54 	struct pcap_keys *pcap_keys;
55 	struct input_dev *input_dev;
56 
57 	pcap_keys = kmalloc(sizeof(struct pcap_keys), GFP_KERNEL);
58 	if (!pcap_keys)
59 		return err;
60 
61 	pcap_keys->pcap = dev_get_drvdata(pdev->dev.parent);
62 
63 	input_dev = input_allocate_device();
64 	if (!input_dev)
65 		goto fail;
66 
67 	pcap_keys->input = input_dev;
68 
69 	platform_set_drvdata(pdev, pcap_keys);
70 	input_dev->name = pdev->name;
71 	input_dev->phys = "pcap-keys/input0";
72 	input_dev->id.bustype = BUS_HOST;
73 	input_dev->dev.parent = &pdev->dev;
74 
75 	__set_bit(EV_KEY, input_dev->evbit);
76 	__set_bit(KEY_POWER, input_dev->keybit);
77 	__set_bit(KEY_HP, input_dev->keybit);
78 
79 	err = input_register_device(input_dev);
80 	if (err)
81 		goto fail_allocate;
82 
83 	err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
84 			pcap_keys_handler, 0, "Power key", pcap_keys);
85 	if (err)
86 		goto fail_register;
87 
88 	err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
89 			pcap_keys_handler, 0, "Headphone button", pcap_keys);
90 	if (err)
91 		goto fail_pwrkey;
92 
93 	return 0;
94 
95 fail_pwrkey:
96 	free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
97 fail_register:
98 	input_unregister_device(input_dev);
99 	goto fail;
100 fail_allocate:
101 	input_free_device(input_dev);
102 fail:
103 	kfree(pcap_keys);
104 	return err;
105 }
106 
107 static int __devexit pcap_keys_remove(struct platform_device *pdev)
108 {
109 	struct pcap_keys *pcap_keys = platform_get_drvdata(pdev);
110 
111 	free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
112 	free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC), pcap_keys);
113 
114 	input_unregister_device(pcap_keys->input);
115 	kfree(pcap_keys);
116 
117 	return 0;
118 }
119 
120 static struct platform_driver pcap_keys_device_driver = {
121 	.probe		= pcap_keys_probe,
122 	.remove		= __devexit_p(pcap_keys_remove),
123 	.driver		= {
124 		.name	= "pcap-keys",
125 		.owner	= THIS_MODULE,
126 	}
127 };
128 module_platform_driver(pcap_keys_device_driver);
129 
130 MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
131 MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
132 MODULE_LICENSE("GPL");
133 MODULE_ALIAS("platform:pcap_keys");
134