1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * drivers/extcon/extcon-adc-jack.c
4 *
5 * Analog Jack extcon driver with ADC-based detection capability.
6 *
7 * Copyright (C) 2016 Samsung Electronics
8 * Chanwoo Choi <cw00.choi@samsung.com>
9 *
10 * Copyright (C) 2012 Samsung Electronics
11 * MyungJoo Ham <myungjoo.ham@samsung.com>
12 *
13 * Modified for calling to IIO to get adc by <anish.singh@samsung.com>
14 */
15
16#include <linux/module.h>
17#include <linux/slab.h>
18#include <linux/device.h>
19#include <linux/platform_device.h>
20#include <linux/err.h>
21#include <linux/interrupt.h>
22#include <linux/workqueue.h>
23#include <linux/iio/consumer.h>
24#include <linux/extcon/extcon-adc-jack.h>
25#include <linux/extcon-provider.h>
26
27/**
28 * struct adc_jack_data - internal data for adc_jack device driver
29 * @edev:		extcon device.
30 * @cable_names:	list of supported cables.
31 * @adc_conditions:	list of adc value conditions.
32 * @num_conditions:	size of adc_conditions.
33 * @irq:		irq number of attach/detach event (0 if not exist).
34 * @handling_delay:	interrupt handler will schedule extcon event
35 *			handling at handling_delay jiffies.
36 * @handler:		extcon event handler called by interrupt handler.
37 * @chan:		iio channel being queried.
38 */
39struct adc_jack_data {
40	struct device *dev;
41	struct extcon_dev *edev;
42
43	const unsigned int **cable_names;
44	struct adc_jack_cond *adc_conditions;
45	int num_conditions;
46
47	int irq;
48	unsigned long handling_delay; /* in jiffies */
49	struct delayed_work handler;
50
51	struct iio_channel *chan;
52	bool wakeup_source;
53};
54
55static void adc_jack_handler(struct work_struct *work)
56{
57	struct adc_jack_data *data = container_of(to_delayed_work(work),
58			struct adc_jack_data,
59			handler);
60	struct adc_jack_cond *def;
61	int ret, adc_val;
62	int i;
63
64	ret = iio_read_channel_raw(data->chan, &adc_val);
65	if (ret < 0) {
66		dev_err(data->dev, "read channel() error: %d\n", ret);
67		return;
68	}
69
70	/* Get state from adc value with adc_conditions */
71	for (i = 0; i < data->num_conditions; i++) {
72		def = &data->adc_conditions[i];
73		if (def->min_adc <= adc_val && def->max_adc >= adc_val) {
74			extcon_set_state_sync(data->edev, def->id, true);
75			return;
76		}
77	}
78
79	/* Set the detached state if adc value is not included in the range */
80	for (i = 0; i < data->num_conditions; i++) {
81		def = &data->adc_conditions[i];
82		extcon_set_state_sync(data->edev, def->id, false);
83	}
84}
85
86static irqreturn_t adc_jack_irq_thread(int irq, void *_data)
87{
88	struct adc_jack_data *data = _data;
89
90	queue_delayed_work(system_power_efficient_wq,
91			   &data->handler, data->handling_delay);
92	return IRQ_HANDLED;
93}
94
95static int adc_jack_probe(struct platform_device *pdev)
96{
97	struct adc_jack_data *data;
98	struct adc_jack_pdata *pdata = dev_get_platdata(&pdev->dev);
99	int i, err = 0;
100
101	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
102	if (!data)
103		return -ENOMEM;
104
105	if (!pdata->cable_names) {
106		dev_err(&pdev->dev, "error: cable_names not defined.\n");
107		return -EINVAL;
108	}
109
110	data->dev = &pdev->dev;
111	data->edev = devm_extcon_dev_allocate(&pdev->dev, pdata->cable_names);
112	if (IS_ERR(data->edev)) {
113		dev_err(&pdev->dev, "failed to allocate extcon device\n");
114		return -ENOMEM;
115	}
116
117	if (!pdata->adc_conditions) {
118		dev_err(&pdev->dev, "error: adc_conditions not defined.\n");
119		return -EINVAL;
120	}
121	data->adc_conditions = pdata->adc_conditions;
122
123	/* Check the length of array and set num_conditions */
124	for (i = 0; data->adc_conditions[i].id != EXTCON_NONE; i++);
125	data->num_conditions = i;
126
127	data->chan = devm_iio_channel_get(&pdev->dev, pdata->consumer_channel);
128	if (IS_ERR(data->chan))
129		return PTR_ERR(data->chan);
130
131	data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms);
132	data->wakeup_source = pdata->wakeup_source;
133
134	INIT_DEFERRABLE_WORK(&data->handler, adc_jack_handler);
135
136	platform_set_drvdata(pdev, data);
137
138	err = devm_extcon_dev_register(&pdev->dev, data->edev);
139	if (err)
140		return err;
141
142	data->irq = platform_get_irq(pdev, 0);
143	if (data->irq < 0)
144		return -ENODEV;
145
146	err = request_any_context_irq(data->irq, adc_jack_irq_thread,
147			pdata->irq_flags, pdata->name, data);
148
149	if (err < 0) {
150		dev_err(&pdev->dev, "error: irq %d\n", data->irq);
151		return err;
152	}
153
154	if (data->wakeup_source)
155		device_init_wakeup(&pdev->dev, 1);
156
157	adc_jack_handler(&data->handler.work);
158	return 0;
159}
160
161static int adc_jack_remove(struct platform_device *pdev)
162{
163	struct adc_jack_data *data = platform_get_drvdata(pdev);
164
165	free_irq(data->irq, data);
166	cancel_work_sync(&data->handler.work);
167
168	return 0;
169}
170
171#ifdef CONFIG_PM_SLEEP
172static int adc_jack_suspend(struct device *dev)
173{
174	struct adc_jack_data *data = dev_get_drvdata(dev);
175
176	cancel_delayed_work_sync(&data->handler);
177	if (device_may_wakeup(data->dev))
178		enable_irq_wake(data->irq);
179
180	return 0;
181}
182
183static int adc_jack_resume(struct device *dev)
184{
185	struct adc_jack_data *data = dev_get_drvdata(dev);
186
187	if (device_may_wakeup(data->dev))
188		disable_irq_wake(data->irq);
189
190	return 0;
191}
192#endif /* CONFIG_PM_SLEEP */
193
194static SIMPLE_DEV_PM_OPS(adc_jack_pm_ops,
195		adc_jack_suspend, adc_jack_resume);
196
197static struct platform_driver adc_jack_driver = {
198	.probe          = adc_jack_probe,
199	.remove         = adc_jack_remove,
200	.driver         = {
201		.name   = "adc-jack",
202		.pm = &adc_jack_pm_ops,
203	},
204};
205
206module_platform_driver(adc_jack_driver);
207
208MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
209MODULE_DESCRIPTION("ADC Jack extcon driver");
210MODULE_LICENSE("GPL v2");
211