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 * @dev: The device structure associated with the adc_jack.
30 * @edev: extcon device.
31 * @cable_names: list of supported cables.
32 * @adc_conditions: list of adc value conditions.
33 * @num_conditions: size of adc_conditions.
34 * @irq: irq number of attach/detach event (0 if not exist).
35 * @handling_delay: interrupt handler will schedule extcon event
36 * handling at handling_delay jiffies.
37 * @handler: extcon event handler called by interrupt handler.
38 * @chan: iio channel being queried.
39 * @wakeup_source: Indicates if the device can wake up the system.
40 */
41struct adc_jack_data {
42 struct device *dev;
43 struct extcon_dev *edev;
44
45 const unsigned int **cable_names;
46 struct adc_jack_cond *adc_conditions;
47 int num_conditions;
48
49 int irq;
50 unsigned long handling_delay; /* in jiffies */
51 struct delayed_work handler;
52
53 struct iio_channel *chan;
54 bool wakeup_source;
55};
56
57static void adc_jack_handler(struct work_struct *work)
58{
59 struct adc_jack_data *data = container_of(to_delayed_work(work),
60 struct adc_jack_data,
61 handler);
62 struct adc_jack_cond *def;
63 int ret, adc_val;
64 int i;
65
66 ret = iio_read_channel_raw(chan: data->chan, val: &adc_val);
67 if (ret < 0) {
68 dev_err(data->dev, "read channel() error: %d\n", ret);
69 return;
70 }
71
72 /* Get state from adc value with adc_conditions */
73 for (i = 0; i < data->num_conditions; i++) {
74 def = &data->adc_conditions[i];
75 if (def->min_adc <= adc_val && def->max_adc >= adc_val) {
76 extcon_set_state_sync(edev: data->edev, id: def->id, state: true);
77 return;
78 }
79 }
80
81 /* Set the detached state if adc value is not included in the range */
82 for (i = 0; i < data->num_conditions; i++) {
83 def = &data->adc_conditions[i];
84 extcon_set_state_sync(edev: data->edev, id: def->id, state: false);
85 }
86}
87
88static irqreturn_t adc_jack_irq_thread(int irq, void *_data)
89{
90 struct adc_jack_data *data = _data;
91
92 queue_delayed_work(wq: system_power_efficient_wq,
93 dwork: &data->handler, delay: data->handling_delay);
94 return IRQ_HANDLED;
95}
96
97static int adc_jack_probe(struct platform_device *pdev)
98{
99 struct adc_jack_data *data;
100 struct adc_jack_pdata *pdata = dev_get_platdata(dev: &pdev->dev);
101 int i, err = 0;
102
103 data = devm_kzalloc(dev: &pdev->dev, size: sizeof(*data), GFP_KERNEL);
104 if (!data)
105 return -ENOMEM;
106
107 if (!pdata->cable_names) {
108 dev_err(&pdev->dev, "error: cable_names not defined.\n");
109 return -EINVAL;
110 }
111
112 data->dev = &pdev->dev;
113 data->edev = devm_extcon_dev_allocate(dev: &pdev->dev, cable: pdata->cable_names);
114 if (IS_ERR(ptr: data->edev)) {
115 dev_err(&pdev->dev, "failed to allocate extcon device\n");
116 return -ENOMEM;
117 }
118
119 if (!pdata->adc_conditions) {
120 dev_err(&pdev->dev, "error: adc_conditions not defined.\n");
121 return -EINVAL;
122 }
123 data->adc_conditions = pdata->adc_conditions;
124
125 /* Check the length of array and set num_conditions */
126 for (i = 0; data->adc_conditions[i].id != EXTCON_NONE; i++);
127 data->num_conditions = i;
128
129 data->chan = devm_iio_channel_get(dev: &pdev->dev, consumer_channel: pdata->consumer_channel);
130 if (IS_ERR(ptr: data->chan))
131 return PTR_ERR(ptr: data->chan);
132
133 data->handling_delay = msecs_to_jiffies(m: pdata->handling_delay_ms);
134 data->wakeup_source = pdata->wakeup_source;
135
136 INIT_DEFERRABLE_WORK(&data->handler, adc_jack_handler);
137
138 platform_set_drvdata(pdev, data);
139
140 err = devm_extcon_dev_register(dev: &pdev->dev, edev: data->edev);
141 if (err)
142 return err;
143
144 data->irq = platform_get_irq(pdev, 0);
145 if (data->irq < 0)
146 return -ENODEV;
147
148 err = request_any_context_irq(irq: data->irq, handler: adc_jack_irq_thread,
149 flags: pdata->irq_flags, name: pdata->name, dev_id: data);
150
151 if (err < 0) {
152 dev_err(&pdev->dev, "error: irq %d\n", data->irq);
153 return err;
154 }
155
156 if (data->wakeup_source)
157 device_init_wakeup(dev: &pdev->dev, enable: 1);
158
159 adc_jack_handler(work: &data->handler.work);
160 return 0;
161}
162
163static void adc_jack_remove(struct platform_device *pdev)
164{
165 struct adc_jack_data *data = platform_get_drvdata(pdev);
166
167 if (data->wakeup_source)
168 device_init_wakeup(dev: &pdev->dev, enable: false);
169 free_irq(data->irq, data);
170 cancel_work_sync(work: &data->handler.work);
171}
172
173#ifdef CONFIG_PM_SLEEP
174static int adc_jack_suspend(struct device *dev)
175{
176 struct adc_jack_data *data = dev_get_drvdata(dev);
177
178 cancel_delayed_work_sync(dwork: &data->handler);
179 if (device_may_wakeup(dev: data->dev))
180 enable_irq_wake(irq: data->irq);
181
182 return 0;
183}
184
185static int adc_jack_resume(struct device *dev)
186{
187 struct adc_jack_data *data = dev_get_drvdata(dev);
188
189 if (device_may_wakeup(dev: data->dev))
190 disable_irq_wake(irq: data->irq);
191
192 return 0;
193}
194#endif /* CONFIG_PM_SLEEP */
195
196static SIMPLE_DEV_PM_OPS(adc_jack_pm_ops,
197 adc_jack_suspend, adc_jack_resume);
198
199static struct platform_driver adc_jack_driver = {
200 .probe = adc_jack_probe,
201 .remove = adc_jack_remove,
202 .driver = {
203 .name = "adc-jack",
204 .pm = &adc_jack_pm_ops,
205 },
206};
207
208module_platform_driver(adc_jack_driver);
209
210MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
211MODULE_DESCRIPTION("ADC Jack extcon driver");
212MODULE_LICENSE("GPL v2");
213

source code of linux/drivers/extcon/extcon-adc-jack.c