19939860 |
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/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.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 | * @num_cables - size of cable_names. |
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 extcon_dev edev; |
42 | |
43 | const char **cable_names; |
44 | int num_cables; |
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 | }; |
54 | |
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 | u32 state = 0; |
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->edev.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 | struct adc_jack_cond *def = &data->adc_conditions[i]; |
73 | if (!def->state) |
74 | break; |
75 | if (def->min_adc <= adc_val && def->max_adc >= adc_val) { |
76 | state = def->state; |
77 | break; |
78 | } |
79 | } |
80 | /* if no def has met, it means state = 0 (no cables attached) */ |
81 | |
82 | extcon_set_state(&data->edev, state); |
83 | } |
84 | |
85 | static irqreturn_t adc_jack_irq_thread(int irq, void *_data) |
86 | { |
87 | struct adc_jack_data *data = _data; |
88 | |
89 | schedule_delayed_work(&data->handler, data->handling_delay); |
90 | return IRQ_HANDLED; |
91 | } |
92 | |
93 | static int __devinit adc_jack_probe(struct platform_device *pdev) |
94 | { |
95 | struct adc_jack_data *data; |
96 | struct adc_jack_pdata *pdata = pdev->dev.platform_data; |
97 | int i, err = 0; |
98 | |
99 | data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); |
100 | if (!data) |
101 | return -ENOMEM; |
102 | |
103 | data->edev.name = pdata->name; |
104 | |
105 | if (!pdata->cable_names) { |
106 | err = -EINVAL; |
107 | dev_err(&pdev->dev, "error: cable_names not defined.\n"); |
108 | goto out; |
109 | } |
110 | |
111 | data->edev.supported_cable = pdata->cable_names; |
112 | |
113 | /* Check the length of array and set num_cables */ |
114 | for (i = 0; data->edev.supported_cable[i]; i++) |
115 | ; |
116 | if (i == 0 || i > SUPPORTED_CABLE_MAX) { |
117 | err = -EINVAL; |
118 | dev_err(&pdev->dev, "error: pdata->cable_names size = %d\n", |
119 | i - 1); |
120 | goto out; |
121 | } |
122 | data->num_cables = i; |
123 | |
124 | if (!pdata->adc_conditions || |
125 | !pdata->adc_conditions[0].state) { |
126 | err = -EINVAL; |
127 | dev_err(&pdev->dev, "error: adc_conditions not defined.\n"); |
128 | goto out; |
129 | } |
130 | data->adc_conditions = pdata->adc_conditions; |
131 | |
132 | /* Check the length of array and set num_conditions */ |
133 | for (i = 0; data->adc_conditions[i].state; i++) |
134 | ; |
135 | data->num_conditions = i; |
136 | |
137 | data->chan = iio_channel_get(dev_name(&pdev->dev), |
138 | pdata->consumer_channel); |
139 | if (IS_ERR(data->chan)) { |
140 | err = PTR_ERR(data->chan); |
141 | goto out; |
142 | } |
143 | |
144 | data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms); |
145 | |
146 | INIT_DELAYED_WORK_DEFERRABLE(&data->handler, adc_jack_handler); |
147 | |
148 | platform_set_drvdata(pdev, data); |
149 | |
150 | err = extcon_dev_register(&data->edev, &pdev->dev); |
151 | if (err) |
152 | goto out; |
153 | |
154 | data->irq = platform_get_irq(pdev, 0); |
155 | if (!data->irq) { |
156 | dev_err(&pdev->dev, "platform_get_irq failed\n"); |
157 | err = -ENODEV; |
158 | goto err_irq; |
159 | } |
160 | |
161 | err = request_any_context_irq(data->irq, adc_jack_irq_thread, |
162 | pdata->irq_flags, pdata->name, data); |
163 | |
164 | if (err) { |
165 | dev_err(&pdev->dev, "error: irq %d\n", data->irq); |
166 | err = -EINVAL; |
167 | goto err_irq; |
168 | } |
169 | |
170 | goto out; |
171 | |
172 | err_irq: |
173 | extcon_dev_unregister(&data->edev); |
174 | out: |
175 | return err; |
176 | } |
177 | |
178 | static int __devexit adc_jack_remove(struct platform_device *pdev) |
179 | { |
180 | struct adc_jack_data *data = platform_get_drvdata(pdev); |
181 | |
182 | free_irq(data->irq, data); |
183 | cancel_work_sync(&data->handler.work); |
184 | extcon_dev_unregister(&data->edev); |
185 | |
186 | return 0; |
187 | } |
188 | |
189 | static struct platform_driver adc_jack_driver = { |
190 | .probe = adc_jack_probe, |
191 | .remove = __devexit_p(adc_jack_remove), |
192 | .driver = { |
193 | .name = "adc-jack", |
194 | .owner = THIS_MODULE, |
195 | }, |
196 | }; |
197 | |
198 | module_platform_driver(adc_jack_driver); |