1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Input driver for PCAP events:
4 * * Power key
5 * * Headphone button
6 *
7 * Copyright (c) 2008,2009 Ilya Petrov <ilya.muromec@gmail.com>
8 */
9
10#include <linux/module.h>
11#include <linux/interrupt.h>
12#include <linux/platform_device.h>
13#include <linux/input.h>
14#include <linux/mfd/ezx-pcap.h>
15#include <linux/slab.h>
16
17struct pcap_keys {
18 struct pcap_chip *pcap;
19 struct input_dev *input;
20};
21
22/* PCAP2 interrupts us on keypress */
23static irqreturn_t pcap_keys_handler(int irq, void *_pcap_keys)
24{
25 struct pcap_keys *pcap_keys = _pcap_keys;
26 int pirq = irq_to_pcap(pcap_keys->pcap, irq);
27 u32 pstat;
28
29 ezx_pcap_read(pcap_keys->pcap, PCAP_REG_PSTAT, &pstat);
30 pstat &= 1 << pirq;
31
32 switch (pirq) {
33 case PCAP_IRQ_ONOFF:
34 input_report_key(dev: pcap_keys->input, KEY_POWER, value: !pstat);
35 break;
36 case PCAP_IRQ_MIC:
37 input_report_key(dev: pcap_keys->input, KEY_HP, value: !pstat);
38 break;
39 }
40
41 input_sync(dev: pcap_keys->input);
42
43 return IRQ_HANDLED;
44}
45
46static int pcap_keys_probe(struct platform_device *pdev)
47{
48 int err = -ENOMEM;
49 struct pcap_keys *pcap_keys;
50 struct input_dev *input_dev;
51
52 pcap_keys = kmalloc(size: sizeof(struct pcap_keys), GFP_KERNEL);
53 if (!pcap_keys)
54 return err;
55
56 pcap_keys->pcap = dev_get_drvdata(dev: pdev->dev.parent);
57
58 input_dev = input_allocate_device();
59 if (!input_dev)
60 goto fail;
61
62 pcap_keys->input = input_dev;
63
64 platform_set_drvdata(pdev, data: pcap_keys);
65 input_dev->name = pdev->name;
66 input_dev->phys = "pcap-keys/input0";
67 input_dev->id.bustype = BUS_HOST;
68 input_dev->dev.parent = &pdev->dev;
69
70 __set_bit(EV_KEY, input_dev->evbit);
71 __set_bit(KEY_POWER, input_dev->keybit);
72 __set_bit(KEY_HP, input_dev->keybit);
73
74 err = input_register_device(input_dev);
75 if (err)
76 goto fail_allocate;
77
78 err = request_irq(irq: pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
79 handler: pcap_keys_handler, flags: 0, name: "Power key", dev: pcap_keys);
80 if (err)
81 goto fail_register;
82
83 err = request_irq(irq: pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
84 handler: pcap_keys_handler, flags: 0, name: "Headphone button", dev: pcap_keys);
85 if (err)
86 goto fail_pwrkey;
87
88 return 0;
89
90fail_pwrkey:
91 free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
92fail_register:
93 input_unregister_device(input_dev);
94 goto fail;
95fail_allocate:
96 input_free_device(dev: input_dev);
97fail:
98 kfree(objp: pcap_keys);
99 return err;
100}
101
102static int pcap_keys_remove(struct platform_device *pdev)
103{
104 struct pcap_keys *pcap_keys = platform_get_drvdata(pdev);
105
106 free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
107 free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC), pcap_keys);
108
109 input_unregister_device(pcap_keys->input);
110 kfree(objp: pcap_keys);
111
112 return 0;
113}
114
115static struct platform_driver pcap_keys_device_driver = {
116 .probe = pcap_keys_probe,
117 .remove = pcap_keys_remove,
118 .driver = {
119 .name = "pcap-keys",
120 }
121};
122module_platform_driver(pcap_keys_device_driver);
123
124MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
125MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
126MODULE_LICENSE("GPL");
127MODULE_ALIAS("platform:pcap_keys");
128

source code of linux/drivers/input/misc/pcap_keys.c