diff options
| -rw-r--r-- | drivers/extcon/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/extcon/Makefile | 1 | ||||
| -rw-r--r-- | drivers/extcon/extcon-adc-jack.c | 195 | ||||
| -rw-r--r-- | include/linux/extcon/extcon-adc-jack.h | 73 |
4 files changed, 275 insertions, 0 deletions
diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig index e175c8ed4ec4..dd5b01b957aa 100644 --- a/drivers/extcon/Kconfig +++ b/drivers/extcon/Kconfig @@ -21,6 +21,12 @@ config EXTCON_GPIO Say Y here to enable GPIO based extcon support. Note that GPIO extcon supports single state per extcon instance. +config EXTCON_ADC_JACK + tristate "ADC Jack extcon support" + depends on IIO + help + Say Y here to enable extcon device driver based on ADC values. + config EXTCON_MAX77693 tristate "MAX77693 EXTCON Support" depends on MFD_MAX77693 diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile index 88961b332348..53d88c1cce36 100644 --- a/drivers/extcon/Makefile +++ b/drivers/extcon/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_EXTCON) += extcon_class.o obj-$(CONFIG_EXTCON_GPIO) += extcon_gpio.o +obj-$(CONFIG_EXTCON_ADC_JACK) += extcon-adc-jack.o obj-$(CONFIG_EXTCON_MAX77693) += extcon-max77693.o obj-$(CONFIG_EXTCON_MAX8997) += extcon-max8997.o obj-$(CONFIG_EXTCON_ARIZONA) += extcon-arizona.o diff --git a/drivers/extcon/extcon-adc-jack.c b/drivers/extcon/extcon-adc-jack.c new file mode 100644 index 000000000000..da058f7033ef --- /dev/null +++ b/drivers/extcon/extcon-adc-jack.c @@ -0,0 +1,195 @@ +/* + * 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/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; + + schedule_delayed_work(&data->handler, data->handling_delay); + return IRQ_HANDLED; +} + +static int __devinit adc_jack_probe(struct platform_device *pdev) +{ + struct adc_jack_data *data; + struct adc_jack_pdata *pdata = pdev->dev.platform_data; + int i, err = 0; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->edev.name = pdata->name; + + if (pdata->cable_names) + data->edev.supported_cable = pdata->cable_names; + else + data->edev.supported_cable = extcon_cable_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) { + err = -EINVAL; + dev_err(&pdev->dev, "error: pdata->cable_names size = %d\n", + i - 1); + goto out; + } + data->num_cables = i; + + if (!pdata->adc_conditions || + !pdata->adc_conditions[0].state) { + err = -EINVAL; + dev_err(&pdev->dev, "error: adc_conditions not defined.\n"); + goto out; + } + 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(dev_name(&pdev->dev), + pdata->consumer_channel); + if (IS_ERR(data->chan)) { + err = PTR_ERR(data->chan); + goto out; + } + + data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms); + + INIT_DELAYED_WORK_DEFERRABLE(&data->handler, adc_jack_handler); + + platform_set_drvdata(pdev, data); + + err = extcon_dev_register(&data->edev, &pdev->dev); + if (err) + goto out; + + data->irq = platform_get_irq(pdev, 0); + if (!data->irq) { + dev_err(&pdev->dev, "platform_get_irq failed\n"); + err = -ENODEV; + goto err_irq; + } + + err = request_any_context_irq(data->irq, adc_jack_irq_thread, + pdata->irq_flags, pdata->name, data); + + if (err) { + dev_err(&pdev->dev, "error: irq %d\n", data->irq); + err = -EINVAL; + goto err_irq; + } + + goto out; + +err_irq: + extcon_dev_unregister(&data->edev); +out: + return err; +} + +static int __devexit 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); + extcon_dev_unregister(&data->edev); + + return 0; +} + +static struct platform_driver adc_jack_driver = { + .probe = adc_jack_probe, + .remove = __devexit_p(adc_jack_remove), + .driver = { + .name = "adc-jack", + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(adc_jack_driver); diff --git a/include/linux/extcon/extcon-adc-jack.h b/include/linux/extcon/extcon-adc-jack.h new file mode 100644 index 000000000000..a1603cfc504f --- /dev/null +++ b/include/linux/extcon/extcon-adc-jack.h @@ -0,0 +1,73 @@ +/* + * include/linux/extcon/extcon-adc-jack.h + * + * Analog Jack extcon driver with ADC-based detection capability. + * + * Copyright (C) 2012 Samsung Electronics + * MyungJoo Ham <myungjoo.ham@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. + * + */ + +#ifndef _EXTCON_ADC_JACK_H_ +#define _EXTCON_ADC_JACK_H_ __FILE__ + +#include <linux/module.h> +#include <linux/extcon.h> + +/** + * struct adc_jack_cond - condition to use an extcon state + * @state - the corresponding extcon state (if 0, this struct denotes + * the last adc_jack_cond element among the array) + * @min_adc - min adc value for this condition + * @max_adc - max adc value for this condition + * + * For example, if { .state = 0x3, .min_adc = 100, .max_adc = 200}, it means + * that if ADC value is between (inclusive) 100 and 200, than the cable 0 and + * 1 are attached (1<<0 | 1<<1 == 0x3) + * + * Note that you don't need to describe condition for "no cable attached" + * because when no adc_jack_cond is met, state = 0 is automatically chosen. + */ +struct adc_jack_cond { + u32 state; /* extcon state value. 0 if invalid */ + u32 min_adc; + u32 max_adc; +}; + +/** + * struct adc_jack_pdata - platform data for adc jack device. + * @name - name of the extcon device. If null, "adc-jack" is used. + * @consumer_channel - Unique name to identify the channel on the consumer + * side. This typically describes the channels used within + * the consumer. E.g. 'battery_voltage' + * @cable_names - array of cable names ending with null. If the array itself + * if null, extcon standard cable names are chosen. + * @adc_contitions - array of struct adc_jack_cond conditions ending + * with .state = 0 entry. This describes how to decode + * adc values into extcon state. + * @irq_flags - irq flags used for the @irq + * @handling_delay_ms - in some devices, we need to read ADC value some + * milli-seconds after the interrupt occurs. You may + * describe such delays with @handling_delay_ms, which + * is rounded-off by jiffies. + */ +struct adc_jack_pdata { + const char *name; + const char *consumer_channel; + /* + * NULL if standard extcon names are used. + * The last entry should be NULL + */ + const char **cable_names; + /* The last entry's state should be 0 */ + struct adc_jack_cond *adc_conditions; + + unsigned long irq_flags; + unsigned long handling_delay_ms; /* in ms */ +}; + +#endif /* _EXTCON_ADC_JACK_H */ |