File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/extcon/extcon-adc-jack.c b/drivers/extcon/extcon-adc-jack.c
new file mode 100644
index 0000000..7fc0ae1
--- /dev/null
+++ b/drivers/extcon/extcon-adc-jack.c
@@ -0,0 +1,180 @@
+/*
+ * drivers/extcon/extcon-adc-jack.c
+ *
+ * Analog Jack extcon driver with ADC-based detection capability.
+ *
+ * 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 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;
+};
+
+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);
+ u32 state = 0;
+ 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++) {
+ struct adc_jack_cond *def = &data->adc_conditions[i];
+ if (!def->state)
+ break;
+ if (def->min_adc <= adc_val && def->max_adc >= adc_val) {
+ state = def->state;
+ break;
+ }
+ }
+ /* if no def has met, it means state = 0 (no cables attached) */
+
+ extcon_set_state(data->edev, state);
+}
+
+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->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 ||
+ !pdata->adc_conditions[0].state) {
+ 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].state; 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);
+
+ 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;
+ }
+
+ 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;
+}
+
+static struct platform_driver adc_jack_driver = {
+ .probe = adc_jack_probe,
+ .remove = adc_jack_remove,
+ .driver = {
+ .name = "adc-jack",
+ },
+};
+
+module_platform_driver(adc_jack_driver);
+
+MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
+MODULE_DESCRIPTION("ADC Jack extcon driver");
+MODULE_LICENSE("GPL v2");