On Tue, 2012-08-07 at 05:57 +0000, MyungJoo Ham wrote:
> > From: anish kumar <anish198519851985@xxxxxxxxx>
> >
> > 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 this version:
> > 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.
> >
> > Signed-off-by: anish kumar <anish.singh@xxxxxxxxxxx>
> > Signed-off-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
>
> Hello,
>
>
> One little thing that I've missed before:
>
> Could you please rename the file?
>
> Though the initial files (class and gpio) didn't do it,
> like other recent ones, let's use '-' instead of '_'.
> Besides, could you please use "extcon" prefix for the filename?
>
> Thus, "adc_jack.c/h" --> "extcon-adc-jack.c/h"
Sure updated patch is on the way.
>
>
> Cheers
> MyungJoo
>
> > ---
> > drivers/extcon/Kconfig | 5 +
> > drivers/extcon/Makefile | 1 +
> > drivers/extcon/adc_jack.c | 193 +++++++++++++++++++++++++++++++++++++++
> > include/linux/extcon/adc_jack.h | 77 ++++++++++++++++
> > 4 files changed, 276 insertions(+), 0 deletions(-)
> > create mode 100644 drivers/extcon/adc_jack.c
> > create mode 100644 include/linux/extcon/adc_jack.h
> >
> > diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
> > index e175c8e..596e277 100644
> > --- a/drivers/extcon/Kconfig
> > +++ b/drivers/extcon/Kconfig
> > @@ -21,6 +21,11 @@ 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"
> > + 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 88961b3..d95c5ea 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-$(CONFIG_EXTCON_ADC_JACK) += adc_jack.o
> > obj-$(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/adc_jack.c b/drivers/extcon/adc_jack.c
> > new file mode 100644
> > index 0000000..8b80af0
> > --- /dev/null
> > +++ b/drivers/extcon/adc_jack.c
> > @@ -0,0 +1,193 @@
> > +/*
> > + * drivers/extcon/adc_jack.c
> > + *
> > + * Analog Jack extcon driver with ADC-based detection capability.
> > + *
> > + * Copyright (C) 2012 Samsung Electronics
> > + * MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
> > + *
> > + * Modified for calling to IIO to get adc by <anish.singh@xxxxxxxxxxx>
> > + *
> > + * 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/interrupt.h>
> > +#include <linux/workqueue.h>
> > +#include <linux/iio/consumer.h>
> > +#include <linux/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_condition - list of adc value conditions.
> > + * @num_condition - size of adc_condition.
> > + * @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.
> > + * @get_adc - a callback to get ADC value to identify state.
> > + */
> > +struct adc_jack_data {
> > + struct extcon_dev edev;
> > +
> > + const char **cable_names;
> > + int num_cables;
> > + struct adc_jack_cond *adc_condition;
> > + 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_condition */
> > + for (i = 0; i < data->num_conditions; i++) {
> > + struct adc_jack_cond *def = &data->adc_condition[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 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 err_alloc;
> > + }
> > + data->num_cables = i;
> > +
> > + if (!pdata->adc_condition ||
> > + !pdata->adc_condition[0].state) {
> > + err = -EINVAL;
> > + dev_err(&pdev->dev, "error: adc_condition not defined.\n");
> > + goto err_alloc;
> > + }
> > + data->adc_condition = pdata->adc_condition;
> > +
> > + /* Check the length of array and set num_conditions */
> > + for (i = 0; data->adc_condition[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 err_alloc;
> > + }
> > +
> > + 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 err_initwork;
> > +
> > + data->irq = platform_get_irq(pdev, 0);
> > +
> > + 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);
> > +err_initwork:
> > + cancel_delayed_work_sync(&data->handler);
> > +err_alloc:
> > + kfree(data);
> > +out:
> > + return err;
> > +}
> > +
> > +static int __devexit adc_jack_remove(struct platform_device *pdev)
> > +{
> > + struct adc_jack_data *data = platform_get_drvdata(pdev);
> > +
> > + extcon_dev_unregister(&data->edev);
> > + if (data->irq)
> > + free_irq(data->irq, data);
> > +
> > + 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/adc_jack.h b/include/linux/extcon/adc_jack.h
> > new file mode 100644
> > index 0000000..ca4d1cd
> > --- /dev/null
> > +++ b/include/linux/extcon/adc_jack.h
> > @@ -0,0 +1,77 @@
> > +/*
> > + * include/linux/extcon/adc_jack.h
> > + *
> > + * Analog Jack extcon driver with ADC-based detection capability.
> > + *
> > + * Copyright (C) 2012 Samsung Electronics
> > + * MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
> > + *
> > + * 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.
> > + * @cable_names - array of cable names ending with null. If the array itself
> > + * if null, extcon standard cable names are chosen.
> > + * @adc_contition - array of struct adc_jack_cond conditions ending
> > + * with .state = 0 entry. This describes how to decode
> > + * adc values into extcon state.
> > + * @irq - IRQ number that is triggerred by cable attach/detach
> > + * events. If irq = 0, use should manually update extcon state
> > + * with extcon APIs.
> > + * @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.
> > + * @get_adc - the callback to read ADC value to identify cable states.
> > + */
> > +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_condition;
> > +
> > + unsigned long irq_flags;
> > + unsigned long handling_delay_ms; /* in ms */
> > +
> > + /* When we have ADC subsystem, this can be generalized. */
> > + int (*get_adc)(u32 *value);
> > +};
> > +
> > +#endif /* _EXTCON_ADC_JACK_H */
> > --
> > 1.7.1
> >
> >
> >
> >
> >
> >
> >
> >
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