extcon: adc_jack: adc-jack driver to support 3.5 pi or simliar devices
External connector devices that decides connection information based on ADC values may use adc-jack device driver. The user simply needs to provide a table of adc range and connection states. Then, extcon framework will automatically notify others. Changes in V1: added Lars-Peter Clausen suggested changes: Using macros to get rid of boiler plate code such as devm_kzalloc and module_platform_driver.Other changes suggested are related to coding guidelines. Changes in V2: Removed some unnecessary checks and changed the way we are un-regitering extcon and freeing the irq while removing. Changes in V3: Renamed the files to comply with extcon naming. Changes in V4: Added the cancel_work_sync during removing of driver. Changes in V5: Added the dependency of IIO in Kconfig. Changes in V6: Some nitpicks related to naming. Changes in this version: V6 patch version patch broke the build: ERROR: "extcon_cable_name" [drivers/extcon/extcon-adc-jack.ko] undefined! Fixed it in this version. Acked-by: Jonathan Cameron <jic23@kernel.org> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: anish kumar <anish.singh@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
c338bb0380
commit
19939860dc
|
@ -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
|
||||
|
|
|
@ -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
|
||||
|
|
|
@ -0,0 +1,198 @@
|
|||
/*
|
||||
* 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) {
|
||||
err = -EINVAL;
|
||||
dev_err(&pdev->dev, "error: cable_names not defined.\n");
|
||||
goto out;
|
||||
}
|
||||
|
||||
data->edev.supported_cable = pdata->cable_names;
|
||||
|
||||
/* 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);
|
|
@ -0,0 +1,71 @@
|
|||
/*
|
||||
* 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.
|
||||
* @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;
|
||||
/*
|
||||
* 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 */
|
Loading…
Reference in New Issue