Version:  2.0.40 2.2.26 2.4.37 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8

Linux/drivers/extcon/extcon-adc-jack.c

  1 /*
  2  * drivers/extcon/extcon-adc-jack.c
  3  *
  4  * Analog Jack extcon driver with ADC-based detection capability.
  5  *
  6  * Copyright (C) 2012 Samsung Electronics
  7  * MyungJoo Ham <myungjoo.ham@samsung.com>
  8  *
  9  * Modified for calling to IIO to get adc by <anish.singh@samsung.com>
 10  *
 11  * This program is free software; you can redistribute it and/or modify
 12  * it under the terms of the GNU General Public License version 2 as
 13  * published by the Free Software Foundation.
 14  *
 15  */
 16 
 17 #include <linux/module.h>
 18 #include <linux/slab.h>
 19 #include <linux/device.h>
 20 #include <linux/platform_device.h>
 21 #include <linux/err.h>
 22 #include <linux/interrupt.h>
 23 #include <linux/workqueue.h>
 24 #include <linux/iio/consumer.h>
 25 #include <linux/extcon/extcon-adc-jack.h>
 26 #include <linux/extcon.h>
 27 
 28 /**
 29  * struct adc_jack_data - internal data for adc_jack device driver
 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  */
 40 struct adc_jack_data {
 41         struct device *dev;
 42         struct extcon_dev *edev;
 43 
 44         const unsigned int **cable_names;
 45         struct adc_jack_cond *adc_conditions;
 46         int num_conditions;
 47 
 48         int irq;
 49         unsigned long handling_delay; /* in jiffies */
 50         struct delayed_work handler;
 51 
 52         struct iio_channel *chan;
 53         bool wakeup_source;
 54 };
 55 
 56 static void adc_jack_handler(struct work_struct *work)
 57 {
 58         struct adc_jack_data *data = container_of(to_delayed_work(work),
 59                         struct adc_jack_data,
 60                         handler);
 61         u32 state = 0;
 62         int ret, adc_val;
 63         int i;
 64 
 65         ret = iio_read_channel_raw(data->chan, &adc_val);
 66         if (ret < 0) {
 67                 dev_err(&data->edev->dev, "read channel() error: %d\n", ret);
 68                 return;
 69         }
 70 
 71         /* Get state from adc value with adc_conditions */
 72         for (i = 0; i < data->num_conditions; i++) {
 73                 struct adc_jack_cond *def = &data->adc_conditions[i];
 74                 if (!def->state)
 75                         break;
 76                 if (def->min_adc <= adc_val && def->max_adc >= adc_val) {
 77                         state = def->state;
 78                         break;
 79                 }
 80         }
 81         /* if no def has met, it means state = 0 (no cables attached) */
 82 
 83         extcon_set_state(data->edev, state);
 84 }
 85 
 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 
 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                         !pdata->adc_conditions[0].state) {
119                 dev_err(&pdev->dev, "error: adc_conditions not defined.\n");
120                 return -EINVAL;
121         }
122         data->adc_conditions = pdata->adc_conditions;
123 
124         /* Check the length of array and set num_conditions */
125         for (i = 0; data->adc_conditions[i].state; i++)
126                 ;
127         data->num_conditions = i;
128 
129         data->chan = iio_channel_get(&pdev->dev, pdata->consumer_channel);
130         if (IS_ERR(data->chan))
131                 return PTR_ERR(data->chan);
132 
133         data->handling_delay = msecs_to_jiffies(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(&pdev->dev, data->edev);
141         if (err)
142                 return err;
143 
144         data->irq = platform_get_irq(pdev, 0);
145         if (!data->irq) {
146                 dev_err(&pdev->dev, "platform_get_irq failed\n");
147                 return -ENODEV;
148         }
149 
150         err = request_any_context_irq(data->irq, adc_jack_irq_thread,
151                         pdata->irq_flags, pdata->name, data);
152 
153         if (err < 0) {
154                 dev_err(&pdev->dev, "error: irq %d\n", data->irq);
155                 return err;
156         }
157 
158         if (data->wakeup_source)
159                 device_init_wakeup(&pdev->dev, 1);
160 
161         return 0;
162 }
163 
164 static int adc_jack_remove(struct platform_device *pdev)
165 {
166         struct adc_jack_data *data = platform_get_drvdata(pdev);
167 
168         free_irq(data->irq, data);
169         cancel_work_sync(&data->handler.work);
170         iio_channel_release(data->chan);
171 
172         return 0;
173 }
174 
175 #ifdef CONFIG_PM_SLEEP
176 static int adc_jack_suspend(struct device *dev)
177 {
178         struct adc_jack_data *data = dev_get_drvdata(dev);
179 
180         cancel_delayed_work_sync(&data->handler);
181         if (device_may_wakeup(data->dev))
182                 enable_irq_wake(data->irq);
183 
184         return 0;
185 }
186 
187 static int adc_jack_resume(struct device *dev)
188 {
189         struct adc_jack_data *data = dev_get_drvdata(dev);
190 
191         if (device_may_wakeup(data->dev))
192                 disable_irq_wake(data->irq);
193 
194         return 0;
195 }
196 #endif /* CONFIG_PM_SLEEP */
197 
198 static SIMPLE_DEV_PM_OPS(adc_jack_pm_ops,
199                 adc_jack_suspend, adc_jack_resume);
200 
201 static struct platform_driver adc_jack_driver = {
202         .probe          = adc_jack_probe,
203         .remove         = adc_jack_remove,
204         .driver         = {
205                 .name   = "adc-jack",
206                 .pm = &adc_jack_pm_ops,
207         },
208 };
209 
210 module_platform_driver(adc_jack_driver);
211 
212 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
213 MODULE_DESCRIPTION("ADC Jack extcon driver");
214 MODULE_LICENSE("GPL v2");
215 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us