1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ON pin driver for Dialog DA9055 PMICs
4 *
5 * Copyright(c) 2012 Dialog Semiconductor Ltd.
6 *
7 * Author: David Dajun Chen <dchen@diasemi.com>
8 */
9
10#include <linux/input.h>
11#include <linux/module.h>
12#include <linux/platform_device.h>
13
14#include <linux/mfd/da9055/core.h>
15#include <linux/mfd/da9055/reg.h>
16
17struct da9055_onkey {
18	struct da9055 *da9055;
19	struct input_dev *input;
20	struct delayed_work work;
21};
22
23static void da9055_onkey_query(struct da9055_onkey *onkey)
24{
25	int key_stat;
26
27	key_stat = da9055_reg_read(onkey->da9055, DA9055_REG_STATUS_A);
28	if (key_stat < 0) {
29		dev_err(onkey->da9055->dev,
30			"Failed to read onkey event %d\n", key_stat);
31	} else {
32		key_stat &= DA9055_NOKEY_STS;
33		/*
34		 * Onkey status bit is cleared when onkey button is released.
35		 */
36		if (!key_stat) {
37			input_report_key(onkey->input, KEY_POWER, 0);
38			input_sync(onkey->input);
39		}
40	}
41
42	/*
43	 * Interrupt is generated only when the ONKEY pin is asserted.
44	 * Hence the deassertion of the pin is simulated through work queue.
45	 */
46	if (key_stat)
47		schedule_delayed_work(&onkey->work, msecs_to_jiffies(10));
48
49}
50
51static void da9055_onkey_work(struct work_struct *work)
52{
53	struct da9055_onkey *onkey = container_of(work, struct da9055_onkey,
54						  work.work);
55
56	da9055_onkey_query(onkey);
57}
58
59static irqreturn_t da9055_onkey_irq(int irq, void *data)
60{
61	struct da9055_onkey *onkey = data;
62
63	input_report_key(onkey->input, KEY_POWER, 1);
64	input_sync(onkey->input);
65
66	da9055_onkey_query(onkey);
67
68	return IRQ_HANDLED;
69}
70
71static int da9055_onkey_probe(struct platform_device *pdev)
72{
73	struct da9055 *da9055 = dev_get_drvdata(pdev->dev.parent);
74	struct da9055_onkey *onkey;
75	struct input_dev *input_dev;
76	int irq, err;
77
78	irq = platform_get_irq_byname(pdev, "ONKEY");
79	if (irq < 0)
80		return -EINVAL;
81
82	onkey = devm_kzalloc(&pdev->dev, sizeof(*onkey), GFP_KERNEL);
83	if (!onkey) {
84		dev_err(&pdev->dev, "Failed to allocate memory\n");
85		return -ENOMEM;
86	}
87
88	input_dev = input_allocate_device();
89	if (!input_dev) {
90		dev_err(&pdev->dev, "Failed to allocate memory\n");
91		return -ENOMEM;
92	}
93
94	onkey->input = input_dev;
95	onkey->da9055 = da9055;
96	input_dev->name = "da9055-onkey";
97	input_dev->phys = "da9055-onkey/input0";
98	input_dev->dev.parent = &pdev->dev;
99
100	input_dev->evbit[0] = BIT_MASK(EV_KEY);
101	__set_bit(KEY_POWER, input_dev->keybit);
102
103	INIT_DELAYED_WORK(&onkey->work, da9055_onkey_work);
104
105	err = request_threaded_irq(irq, NULL, da9055_onkey_irq,
106				   IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
107				   "ONKEY", onkey);
108	if (err < 0) {
109		dev_err(&pdev->dev,
110			"Failed to register ONKEY IRQ %d, error = %d\n",
111			irq, err);
112		goto err_free_input;
113	}
114
115	err = input_register_device(input_dev);
116	if (err) {
117		dev_err(&pdev->dev, "Unable to register input device, %d\n",
118			err);
119		goto err_free_irq;
120	}
121
122	platform_set_drvdata(pdev, onkey);
123
124	return 0;
125
126err_free_irq:
127	free_irq(irq, onkey);
128	cancel_delayed_work_sync(&onkey->work);
129err_free_input:
130	input_free_device(input_dev);
131
132	return err;
133}
134
135static void da9055_onkey_remove(struct platform_device *pdev)
136{
137	struct da9055_onkey *onkey = platform_get_drvdata(pdev);
138	int irq = platform_get_irq_byname(pdev, "ONKEY");
139
140	irq = regmap_irq_get_virq(onkey->da9055->irq_data, irq);
141	free_irq(irq, onkey);
142	cancel_delayed_work_sync(&onkey->work);
143	input_unregister_device(onkey->input);
144}
145
146static struct platform_driver da9055_onkey_driver = {
147	.probe	= da9055_onkey_probe,
148	.remove_new = da9055_onkey_remove,
149	.driver = {
150		.name	= "da9055-onkey",
151	},
152};
153
154module_platform_driver(da9055_onkey_driver);
155
156MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
157MODULE_DESCRIPTION("Onkey driver for DA9055");
158MODULE_LICENSE("GPL");
159MODULE_ALIAS("platform:da9055-onkey");
160