aboutsummaryrefslogtreecommitdiff
path: root/drivers/extcon/extcon-adc-jack.c
blob: bc538708c75370a61ac83b9331e0bf1dd6aea810 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/*
 * drivers/extcon/extcon-adc-jack.c
 *
 * Analog Jack extcon driver with ADC-based detection capability.
 *
 * Copyright (C) 2016 Samsung Electronics
 * Chanwoo Choi <cw00.choi@samsung.com>
 *
 * Copyright (C) 2012 Samsung Electronics
 * MyungJoo Ham <myungjoo.ham@samsung.com>
 *
 * Modified for calling to IIO to get adc by <anish.singh@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/iio/consumer.h>
#include <linux/extcon/extcon-adc-jack.h>
#include <linux/extcon.h>

/**
 * struct adc_jack_data - internal data for adc_jack device driver
 * @edev:		extcon device.
 * @cable_names:	list of supported cables.
 * @adc_conditions:	list of adc value conditions.
 * @num_conditions:	size of adc_conditions.
 * @irq:		irq number of attach/detach event (0 if not exist).
 * @handling_delay:	interrupt handler will schedule extcon event
 *			handling at handling_delay jiffies.
 * @handler:		extcon event handler called by interrupt handler.
 * @chan:		iio channel being queried.
 */
struct adc_jack_data {
	struct device *dev;
	struct extcon_dev *edev;

	const unsigned int **cable_names;
	struct adc_jack_cond *adc_conditions;
	int num_conditions;

	int irq;
	unsigned long handling_delay; /* in jiffies */
	struct delayed_work handler;

	struct iio_channel *chan;
	bool wakeup_source;
};

static void adc_jack_handler(struct work_struct *work)
{
	struct adc_jack_data *data = container_of(to_delayed_work(work),
			struct adc_jack_data,
			handler);
	struct adc_jack_cond *def;
	int ret, adc_val;
	int i;

	ret = iio_read_channel_raw(data->chan, &adc_val);
	if (ret < 0) {
		dev_err(&data->edev->dev, "read channel() error: %d\n", ret);
		return;
	}

	/* Get state from adc value with adc_conditions */
	for (i = 0; i < data->num_conditions; i++) {
		def = &data->adc_conditions[i];
		if (def->min_adc <= adc_val && def->max_adc >= adc_val) {
			extcon_set_state_sync(data->edev, def->id, true);
			return;
		}
	}

	/* Set the detached state if adc value is not included in the range */
	for (i = 0; i < data->num_conditions; i++) {
		def = &data->adc_conditions[i];
		extcon_set_state_sync(data->edev, def->id, false);
	}
}

static irqreturn_t adc_jack_irq_thread(int irq, void *_data)
{
	struct adc_jack_data *data = _data;

	queue_delayed_work(system_power_efficient_wq,
			   &data->handler, data->handling_delay);
	return IRQ_HANDLED;
}

static int adc_jack_probe(struct platform_device *pdev)
{
	struct adc_jack_data *data;
	struct adc_jack_pdata *pdata = dev_get_platdata(&pdev->dev);
	int i, err = 0;

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	if (!pdata->cable_names) {
		dev_err(&pdev->dev, "error: cable_names not defined.\n");
		return -EINVAL;
	}

	data->dev = &pdev->dev;
	data->edev = devm_extcon_dev_allocate(&pdev->dev, pdata->cable_names);
	if (IS_ERR(data->edev)) {
		dev_err(&pdev->dev, "failed to allocate extcon device\n");
		return -ENOMEM;
	}

	if (!pdata->adc_conditions) {
		dev_err(&pdev->dev, "error: adc_conditions not defined.\n");
		return -EINVAL;
	}
	data->adc_conditions = pdata->adc_conditions;

	/* Check the length of array and set num_conditions */
	for (i = 0; data->adc_conditions[i].id != EXTCON_NONE; i++);
	data->num_conditions = i;

	data->chan = iio_channel_get(&pdev->dev, pdata->consumer_channel);
	if (IS_ERR(data->chan))
		return PTR_ERR(data->chan);

	data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms);
	data->wakeup_source = pdata->wakeup_source;

	INIT_DEFERRABLE_WORK(&data->handler, adc_jack_handler);

	platform_set_drvdata(pdev, data);

	err = devm_extcon_dev_register(&pdev->dev, data->edev);
	if (err)
		return err;

	data->irq = platform_get_irq(pdev, 0);
	if (!data->irq) {
		dev_err(&pdev->dev, "platform_get_irq failed\n");
		return -ENODEV;
	}

	err = request_any_context_irq(data->irq, adc_jack_irq_thread,
			pdata->irq_flags, pdata->name, data);

	if (err < 0) {
		dev_err(&pdev->dev, "error: irq %d\n", data->irq);
		return err;
	}

	if (data->wakeup_source)
		device_init_wakeup(&pdev->dev, 1);

	adc_jack_handler(&data->handler.work);
	return 0;
}

static int adc_jack_remove(struct platform_device *pdev)
{
	struct adc_jack_data *data = platform_get_drvdata(pdev);

	free_irq(data->irq, data);
	cancel_work_sync(&data->handler.work);
	iio_channel_release(data->chan);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int adc_jack_suspend(struct device *dev)
{
	struct adc_jack_data *data = dev_get_drvdata(dev);

	cancel_delayed_work_sync(&data->handler);
	if (device_may_wakeup(data->dev))
		enable_irq_wake(data->irq);

	return 0;
}

static int adc_jack_resume(struct device *dev)
{
	struct adc_jack_data *data = dev_get_drvdata(dev);

	if (device_may_wakeup(data->dev))
		disable_irq_wake(data->irq);

	return 0;
}
#endif /* CONFIG_PM_SLEEP */

static SIMPLE_DEV_PM_OPS(adc_jack_pm_ops,
		adc_jack_suspend, adc_jack_resume);

static struct platform_driver adc_jack_driver = {
	.probe          = adc_jack_probe,
	.remove         = adc_jack_remove,
	.driver         = {
		.name   = "adc-jack",
		.pm = &adc_jack_pm_ops,
	},
};

module_platform_driver(adc_jack_driver);

MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
MODULE_DESCRIPTION("ADC Jack extcon driver");
MODULE_LICENSE("GPL v2");