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 */
39 struct 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
adc_jack_handler(struct work_struct * work)55 static 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
adc_jack_irq_thread(int irq,void * _data)86 static 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
adc_jack_probe(struct platform_device * pdev)95 static 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
adc_jack_remove(struct platform_device * pdev)161 static 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
adc_jack_suspend(struct device * dev)172 static 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
adc_jack_resume(struct device * dev)183 static 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
194 static SIMPLE_DEV_PM_OPS(adc_jack_pm_ops,
195 adc_jack_suspend, adc_jack_resume);
196
197 static 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
206 module_platform_driver(adc_jack_driver);
207
208 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
209 MODULE_DESCRIPTION("ADC Jack extcon driver");
210 MODULE_LICENSE("GPL v2");
211