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(pcap_keys->input, KEY_POWER, !pstat);
35		break;
36	case PCAP_IRQ_MIC:
37		input_report_key(pcap_keys->input, KEY_HP, !pstat);
38		break;
39	}
40
41	input_sync(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(sizeof(struct pcap_keys), GFP_KERNEL);
53	if (!pcap_keys)
54		return err;
55
56	pcap_keys->pcap = dev_get_drvdata(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, 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(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
79			pcap_keys_handler, 0, "Power key", pcap_keys);
80	if (err)
81		goto fail_register;
82
83	err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
84			pcap_keys_handler, 0, "Headphone button", 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(input_dev);
97fail:
98	kfree(pcap_keys);
99	return err;
100}
101
102static void 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(pcap_keys);
111}
112
113static struct platform_driver pcap_keys_device_driver = {
114	.probe		= pcap_keys_probe,
115	.remove_new	= pcap_keys_remove,
116	.driver		= {
117		.name	= "pcap-keys",
118	}
119};
120module_platform_driver(pcap_keys_device_driver);
121
122MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
123MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
124MODULE_LICENSE("GPL");
125MODULE_ALIAS("platform:pcap_keys");
126