diff options
Diffstat (limited to 'kernel/drivers/extcon/extcon-adc-jack.c')
| -rw-r--r-- | kernel/drivers/extcon/extcon-adc-jack.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/kernel/drivers/extcon/extcon-adc-jack.c b/kernel/drivers/extcon/extcon-adc-jack.c new file mode 100644 index 000000000..2bb82e550 --- /dev/null +++ b/kernel/drivers/extcon/extcon-adc-jack.c @@ -0,0 +1,193 @@ +/* + * 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. + * @num_cables: size of cable_names. + * @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 char **cable_names; + int num_cables; + 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; + } + data->edev->name = pdata->name; + + /* Check the length of array and set num_cables */ + for (i = 0; data->edev->supported_cable[i]; i++) + ; + if (i == 0 || i > SUPPORTED_CABLE_MAX) { + dev_err(&pdev->dev, "error: pdata->cable_names size = %d\n", + i - 1); + return -EINVAL; + } + data->num_cables = i; + + 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"); |