From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751948Ab2HFFQI (ORCPT ); Mon, 6 Aug 2012 01:16:08 -0400 Received: from mailout2.samsung.com ([203.254.224.25]:59132 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751111Ab2HFFQG (ORCPT ); Mon, 6 Aug 2012 01:16:06 -0400 X-AuditID: cbfee612-b7f2d6d0000007ea-6d-501f531497ef Date: Mon, 06 Aug 2012 05:16:04 +0000 (GMT) From: MyungJoo Ham Subject: Re: [PATCH] Extcon: adc_jack: adc-jack driver to support 3.5 pi or simliar devices To: anish kumar , =?euc-kr?Q?=C3=D6=C2=F9=BF=EC?= , "jic23@cam.ac.uk" Cc: "linux-kernel@vger.kernel.org" , "linux-iio@vger.kernel.org" , ANISH KUMAR Reply-to: myungjoo.ham@samsung.com MIME-version: 1.0 X-MTR: 20120806051520850@myungjoo.ham Msgkey: 20120806051520850@myungjoo.ham X-EPLocale: ko_KR.euc-kr X-Priority: 3 X-EPWebmail-Msg-Type: personal X-EPWebmail-Reply-Demand: 0 X-EPApproval-Locale: X-EPHeader: ML X-EPTrCode: X-EPTrName: X-MLAttribute: X-RootMTR: 20120806051520850@myungjoo.ham X-ParentMTR: X-ArchiveUser: X-CPGSPASS: N Content-type: text/plain; charset=euc-kr MIME-version: 1.0 Message-id: <10387090.59171344230163413.JavaMail.weblogic@epml13> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrNIsWRmVeSWpSXmKPExsVy+t/t6boiwfIBBtMeqFtc3jWHzYHR4/Mm uQDGKC6blNSczLLUIn27BK6MFxe/sRd0VVX0PvNsYPxS1sXIySEkoC6xaMlJNhBbQsBE4s6P FiYIW0ziwr31QHEuoJr5jBILmn8ygyRYBFQkzs2YBZTg4GAT0JOY+TkZJCwsEC2xa9J3VpB6 EYHJjBLrz11iAXGYBZYzSnx6cowdYpuSxJp9r1hAbF4BQYmTM5+wQGxTlfi7dDZUXE1i+asT UFdISMyafoEVwuaVmNH+FKpeTmLa1zXMELa0xPlZGxhhrl78/TFUnF/i2O0dTCCHgvQ+uR8M M2b35i9QDwtITD1zEKpVS+JE0wqoVj6JNQvfssCM2XVqOTNM7/0tc8FOYxZQlJjS/ZAdwtaS +PJjHxuqtziAbEeJ00sUJzDKzUKSmYWkexaSbmQ1CxhZVjGKphYkFxQnpada6BUn5haX5qXr JefnbmIER/kzoR2MyxosDjEKcDAq8fDeMpAPEGJNLCuuzD3EKMHBrCTCm+4sFyDEm5JYWZVa lB9fVJqTWnyIUZqDRUmcd86LL/5CAumJJanZqakFqUUwWSYOTqkGxl3P+F4tkmVdJr8uN+ZA ar1Y0c19LYF3tlW4VRx/0Z20yX7nnPObHf9NvrFJT/Camcf9+Yw8l3ke9W0xkf1iXP3f79CT L3M8/I+ph3d+PZy03NEtPD7ksX2AiLjSFYsNU0Xb5PtzL5h9OpB37aJl4KIVV2P1SxfaWipL nBTUeWwcFNPycddZLSWW4oxEQy3mouJEAOkNLlPuAgAA X-TM-AS-MML: No Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id q765GGMH003475 > From: anish kumar > > 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. > > Signed-off-by: anish kumar Signed-off-by: MyungJoo Ham > --- > drivers/extcon/Kconfig | 5 + > drivers/extcon/Makefile | 1 + > drivers/extcon/adc_jack.c | 183 +++++++++++++++++++++++++++++++++++++++ > include/linux/extcon/adc_jack.h | 108 +++++++++++++++++++++++ > 4 files changed, 297 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..fef8334 > --- /dev/null > +++ b/drivers/extcon/adc_jack.c > @@ -0,0 +1,183 @@ > +/* > + * drivers/extcon/adc_jack.c > + * > + * Analog Jack extcon driver with ADC-based detection capability. > + * > + * Copyright (C) 2012 Samsung Electronics > + * MyungJoo Ham > + * > + * Modified for calling to IIO to get adc by > + * > + * 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 > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +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; > + > + if (!data->ready) > + return; > + > + 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 = kzalloc(sizeof(struct adc_jack_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); > + data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms); > + > + INIT_DELAYED_WORK_DEFERRABLE(&data->handler, adc_jack_handler); > + > + platform_set_drvdata(pdev, data); > + > + if (pdata->irq) { > + data->irq = pdata->irq; > + > + err = request_threaded_irq(data->irq, NULL, > + 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_initwork; > + } > + } > + err = extcon_dev_register(&data->edev, &pdev->dev); > + if (err) > + goto err_irq; > + > + data->ready = true; > + > + goto out; > + > +err_irq: > + if (data->irq) > + free_irq(data->irq, data); > +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); > + platform_set_drvdata(pdev, NULL); > + kfree(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, > + }, > +}; > + > +static int __init adc_jack_init(void) > +{ > + return platform_driver_register(&adc_jack_driver); > +} > + > +static void __exit adc_jack_exit(void) > +{ > + platform_driver_unregister(&adc_jack_driver); > +} > + > +module_init(adc_jack_init); > +module_exit(adc_jack_exit); > diff --git a/include/linux/extcon/adc_jack.h b/include/linux/extcon/adc_jack.h > new file mode 100644 > index 0000000..4d6a1f7 > --- /dev/null > +++ b/include/linux/extcon/adc_jack.h > @@ -0,0 +1,108 @@ > +/* > + * include/linux/extcon/adc_jack.h > + * > + * Analog Jack extcon driver with ADC-based detection capability. > + * > + * Copyright (C) 2012 Samsung Electronics > + * MyungJoo Ham > + * > + * 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 > +#include > + > +/** > + * 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. > + * @chan - iio channel being queried. > + * @ready - true if it is safe to run handler. > + */ > +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; > + > + bool ready; > +}; > + > +/** > + * 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 use 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_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. > + */ > +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; > + > + int irq; /* Jack insertion/removal interrupt */ > + unsigned long irq_flags; > + unsigned long handling_delay_ms; /* in ms */ > +}; > + > +#endif /* _EXTCON_ADC_JACK_H */ > -- > 1.7.1 > > > > > > > > {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I