GNU Linux-libre 4.19.314-gnu1
[releases.git] / drivers / input / misc / pcap_keys.c
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/interrupt.h>
16 #include <linux/platform_device.h>
17 #include <linux/input.h>
18 #include <linux/mfd/ezx-pcap.h>
19 #include <linux/slab.h>
20
21 struct pcap_keys {
22         struct pcap_chip *pcap;
23         struct input_dev *input;
24 };
25
26 /* PCAP2 interrupts us on keypress */
27 static irqreturn_t pcap_keys_handler(int irq, void *_pcap_keys)
28 {
29         struct pcap_keys *pcap_keys = _pcap_keys;
30         int pirq = irq_to_pcap(pcap_keys->pcap, irq);
31         u32 pstat;
32
33         ezx_pcap_read(pcap_keys->pcap, PCAP_REG_PSTAT, &pstat);
34         pstat &= 1 << pirq;
35
36         switch (pirq) {
37         case PCAP_IRQ_ONOFF:
38                 input_report_key(pcap_keys->input, KEY_POWER, !pstat);
39                 break;
40         case PCAP_IRQ_MIC:
41                 input_report_key(pcap_keys->input, KEY_HP, !pstat);
42                 break;
43         }
44
45         input_sync(pcap_keys->input);
46
47         return IRQ_HANDLED;
48 }
49
50 static int pcap_keys_probe(struct platform_device *pdev)
51 {
52         int err = -ENOMEM;
53         struct pcap_keys *pcap_keys;
54         struct input_dev *input_dev;
55
56         pcap_keys = kmalloc(sizeof(struct pcap_keys), GFP_KERNEL);
57         if (!pcap_keys)
58                 return err;
59
60         pcap_keys->pcap = dev_get_drvdata(pdev->dev.parent);
61
62         input_dev = input_allocate_device();
63         if (!input_dev)
64                 goto fail;
65
66         pcap_keys->input = input_dev;
67
68         platform_set_drvdata(pdev, pcap_keys);
69         input_dev->name = pdev->name;
70         input_dev->phys = "pcap-keys/input0";
71         input_dev->id.bustype = BUS_HOST;
72         input_dev->dev.parent = &pdev->dev;
73
74         __set_bit(EV_KEY, input_dev->evbit);
75         __set_bit(KEY_POWER, input_dev->keybit);
76         __set_bit(KEY_HP, input_dev->keybit);
77
78         err = input_register_device(input_dev);
79         if (err)
80                 goto fail_allocate;
81
82         err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
83                         pcap_keys_handler, 0, "Power key", pcap_keys);
84         if (err)
85                 goto fail_register;
86
87         err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
88                         pcap_keys_handler, 0, "Headphone button", pcap_keys);
89         if (err)
90                 goto fail_pwrkey;
91
92         return 0;
93
94 fail_pwrkey:
95         free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
96 fail_register:
97         input_unregister_device(input_dev);
98         goto fail;
99 fail_allocate:
100         input_free_device(input_dev);
101 fail:
102         kfree(pcap_keys);
103         return err;
104 }
105
106 static int pcap_keys_remove(struct platform_device *pdev)
107 {
108         struct pcap_keys *pcap_keys = platform_get_drvdata(pdev);
109
110         free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
111         free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC), pcap_keys);
112
113         input_unregister_device(pcap_keys->input);
114         kfree(pcap_keys);
115
116         return 0;
117 }
118
119 static struct platform_driver pcap_keys_device_driver = {
120         .probe          = pcap_keys_probe,
121         .remove         = pcap_keys_remove,
122         .driver         = {
123                 .name   = "pcap-keys",
124         }
125 };
126 module_platform_driver(pcap_keys_device_driver);
127
128 MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
129 MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
130 MODULE_LICENSE("GPL");
131 MODULE_ALIAS("platform:pcap_keys");