From patchwork Mon Oct 21 04:11:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff LaBundy X-Patchwork-Id: 11201301 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2CD5013BD for ; Mon, 21 Oct 2019 04:19:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 157F720830 for ; Mon, 21 Oct 2019 04:19:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727091AbfJUETX (ORCPT ); Mon, 21 Oct 2019 00:19:23 -0400 Received: from p3plsmtpa06-04.prod.phx3.secureserver.net ([173.201.192.105]:33777 "EHLO p3plsmtpa06-04.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727093AbfJUETX (ORCPT ); Mon, 21 Oct 2019 00:19:23 -0400 Received: from localhost.localdomain ([136.49.227.119]) by :SMTPAUTH: with ESMTPSA id MP2oifB4Hr3FgMP35iDyat; Sun, 20 Oct 2019 21:12:04 -0700 From: Jeff LaBundy To: lee.jones@linaro.org, dmitry.torokhov@gmail.com, jdelvare@suse.com, linux@roeck-us.net, thierry.reding@gmail.com, jic23@kernel.org, devicetree@vger.kernel.org Cc: linux-input@vger.kernel.org, linux-hwmon@vger.kernel.org, u.kleine-koenig@pengutronix.de, linux-pwm@vger.kernel.org, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, linux-iio@vger.kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, Jeff LaBundy Subject: [PATCH 8/8] iio: position: Add support for Azoteq IQS624/625 angle sensor Date: Sun, 20 Oct 2019 23:11:23 -0500 Message-Id: <1571631083-4962-9-git-send-email-jeff@labundy.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1571631083-4962-1-git-send-email-jeff@labundy.com> References: <1571631083-4962-1-git-send-email-jeff@labundy.com> X-CMAE-Envelope: MS4wfCrKAUq7cK63kIZBAVZ3DeYhkNHems3Cp8/Ghwy/Higeru/SSzta8+3iOHp8rgw2EL6mOdAYGmCVCo3KMkZrRHYyGgOU1+gIzUF+JSDZb5KMdjFLS8B0 a1lp6pTrN9N3/WmMHpWIxtOCg1CeMyf9fkSmOPVjHH3FUWDxJ3sdUiNJouyYnoOqON+IyWnhS6wrNDXKunN8erVI3fMoHmXXs7x+suFUXtG6IZrVS290crSM zTwpYDScAVj2s+indksHrJOkWQ0uU6sIStabUDkEfC/mYBZ+SE0E2V/M/OMyF+2KQkV4n2gtrikdPa9PJ2ixWHgy2wszRyyn9wq+2QdlqY+O2f9hWhBR9GfP fY5r0ArZGa8AajBfH8HoT2pRfeDaHaQ0TaFL1UUeb64Qf2LIGjzP1ASLOMwbPQGNAlBrazyIRd6MFcGHAFXvwWlXG+urrZlwCh2pEWkZpaikmkv3k2sJLcTN j1VQJLBO0RS6DIqfMZyDlTGNCVT98mMuInqqfzStp9S+IrETNvLeOngZ0cB/no4tUgfYwoKDGMEaqnTdrTILHe+Y6gRbumAg7kieN2YMovWkKiiYpjl+ZY7P jGdOZ7gmQgHcKgNRzx6WDvpqetI2RjSGiGNfjUuA3kK9heqKUiOGowetCDogwzPNiZUr3HS2vfipcr7rm0hERsmKOYyBQhBVtoa1LA9V320RRbBtsD9WTNCv oRpAh5TE4XWqnsAULuPqiNrL5G4T3fNixSKj2Tb8TCySty231k4jBQ== Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org This patch adds support for the Azoteq IQS624 and IQS625 angular position sensors, capable of reporting the angle of a rotating shaft down to 1 and 10 degrees of accuracy, respectively. This patch also introduces a home for linear and angular position sensors. Unlike resolvers, they are typically contactless and use the Hall effect. Signed-off-by: Jeff LaBundy Acked-by: Jonathan Cameron --- drivers/iio/Kconfig | 1 + drivers/iio/Makefile | 1 + drivers/iio/position/Kconfig | 19 +++ drivers/iio/position/Makefile | 7 + drivers/iio/position/iqs624-pos.c | 302 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 330 insertions(+) create mode 100644 drivers/iio/position/Kconfig create mode 100644 drivers/iio/position/Makefile create mode 100644 drivers/iio/position/iqs624-pos.c diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig index 5bd5185..d5c073a 100644 --- a/drivers/iio/Kconfig +++ b/drivers/iio/Kconfig @@ -88,6 +88,7 @@ source "drivers/iio/orientation/Kconfig" if IIO_TRIGGER source "drivers/iio/trigger/Kconfig" endif #IIO_TRIGGER +source "drivers/iio/position/Kconfig" source "drivers/iio/potentiometer/Kconfig" source "drivers/iio/potentiostat/Kconfig" source "drivers/iio/pressure/Kconfig" diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile index bff682a..1712011 100644 --- a/drivers/iio/Makefile +++ b/drivers/iio/Makefile @@ -31,6 +31,7 @@ obj-y += light/ obj-y += magnetometer/ obj-y += multiplexer/ obj-y += orientation/ +obj-y += position/ obj-y += potentiometer/ obj-y += potentiostat/ obj-y += pressure/ diff --git a/drivers/iio/position/Kconfig b/drivers/iio/position/Kconfig new file mode 100644 index 0000000..ed9f975 --- /dev/null +++ b/drivers/iio/position/Kconfig @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Linear and angular position sensors +# +# When adding new entries keep the list in alphabetical order + +menu "Linear and angular position sensors" + +config IQS624_POS + tristate "Azoteq IQS624/625 angular position sensor" + depends on MFD_IQS62X + help + Say Y here if you want to build support for the Azoteq IQS624 + and IQS625 angular position sensors. + + To compile this driver as a module, choose M here: the module + will be called iqs624-pos. + +endmenu diff --git a/drivers/iio/position/Makefile b/drivers/iio/position/Makefile new file mode 100644 index 0000000..3cbe7a7 --- /dev/null +++ b/drivers/iio/position/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for IIO linear and angular position sensors +# + +# When adding new entries keep the list in alphabetical order + +obj-$(CONFIG_IQS624_POS) += iqs624-pos.o diff --git a/drivers/iio/position/iqs624-pos.c b/drivers/iio/position/iqs624-pos.c new file mode 100644 index 0000000..d975065 --- /dev/null +++ b/drivers/iio/position/iqs624-pos.c @@ -0,0 +1,302 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Azoteq IQS624/625 Angular Position Sensor + * + * Copyright (C) 2019 + * Author: Jeff LaBundy + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define IQS624_POS_DEG_OUT 0x16 + +#define IQS624_POS_SCALE1 (314159 / 180) +#define IQS624_POS_SCALE2 100000 + +struct iqs624_pos_private { + struct iqs62x_core *iqs62x; + struct notifier_block notifier; + struct mutex lock; + bool event_en; + union { + u16 angle; + u8 interval; + }; +}; + +static int iqs624_pos_init(struct iqs624_pos_private *iqs624_pos) +{ + struct iqs62x_core *iqs62x = iqs624_pos->iqs62x; + unsigned int val; + int error; + __le16 val_buf; + + if (iqs62x->dev_desc->prod_num == IQS624_PROD_NUM) { + error = regmap_raw_read(iqs62x->map, IQS624_POS_DEG_OUT, + &val_buf, sizeof(val_buf)); + if (error) + return error; + + iqs624_pos->angle = le16_to_cpu(val_buf); + } else { + error = regmap_read(iqs62x->map, iqs62x->dev_desc->interval, + &val); + if (error) + return error; + + iqs624_pos->interval = val; + } + + mutex_lock(&iqs624_pos->lock); + + /* + * The IQS625 reports angular position in the form of coarse intervals, + * so only interval change events are unmasked. Conversely, the IQS624 + * reports angular position down to one degree of resolution, so wheel + * movement events are unmasked instead. + */ + error = regmap_update_bits(iqs62x->map, IQS624_HALL_UI, + iqs62x->dev_desc->prod_num == + IQS624_PROD_NUM ? IQS624_HALL_UI_WHL_EVENT : + IQS624_HALL_UI_INT_EVENT, + iqs624_pos->event_en ? 0 : 0xFF); + + mutex_unlock(&iqs624_pos->lock); + + return error; +} + +static int iqs624_pos_notifier(struct notifier_block *notifier, + unsigned long event_flags, void *context) +{ + struct iqs62x_event_data *event_data = context; + struct iqs624_pos_private *iqs624_pos; + struct iqs62x_core *iqs62x; + struct iio_dev *indio_dev; + int error; + + iqs624_pos = container_of(notifier, struct iqs624_pos_private, + notifier); + indio_dev = iio_priv_to_dev(iqs624_pos); + iqs62x = iqs624_pos->iqs62x; + + if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) { + error = iqs624_pos_init(iqs624_pos); + if (error) { + dev_err(indio_dev->dev.parent, + "Failed to re-initialize device: %d\n", error); + return NOTIFY_BAD; + } + + return NOTIFY_OK; + } + + if (iqs62x->dev_desc->prod_num == IQS624_PROD_NUM) { + if (event_data->ui_data == iqs624_pos->angle) + return NOTIFY_DONE; + + iqs624_pos->angle = event_data->ui_data; + } else { + if (event_data->interval == iqs624_pos->interval) + return NOTIFY_DONE; + + iqs624_pos->interval = event_data->interval; + } + + if (!iqs624_pos->event_en) + return NOTIFY_OK; + + iio_push_event(indio_dev, + IIO_UNMOD_EVENT_CODE(IIO_ANGL, 0, + IIO_EV_TYPE_CHANGE, + IIO_EV_DIR_NONE), + iio_get_time_ns(indio_dev)); + + return NOTIFY_OK; +} + +static void iqs624_pos_notifier_unregister(void *context) +{ + struct iqs624_pos_private *iqs624_pos = context; + struct iio_dev *indio_dev = iio_priv_to_dev(iqs624_pos); + int error; + + error = blocking_notifier_chain_unregister(&iqs624_pos->iqs62x->nh, + &iqs624_pos->notifier); + if (error) + dev_err(indio_dev->dev.parent, + "Failed to unregister notifier: %d\n", error); +} + +static int iqs624_pos_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct iqs624_pos_private *iqs624_pos = iio_priv(indio_dev); + struct iqs62x_core *iqs62x = iqs624_pos->iqs62x; + int error; + __le16 val_buf; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (iqs62x->dev_desc->prod_num == IQS624_PROD_NUM) { + error = regmap_raw_read(iqs62x->map, IQS624_POS_DEG_OUT, + &val_buf, sizeof(val_buf)); + if (error) + return error; + + *val = le16_to_cpu(val_buf); + } else { + error = regmap_read(iqs62x->map, + iqs62x->dev_desc->interval, val); + if (error) + return error; + } + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + if (iqs62x->dev_desc->prod_num == IQS624_PROD_NUM) { + *val = IQS624_POS_SCALE1; + } else { + error = regmap_read(iqs62x->map, IQS624_INTERVAL_DIV, + val); + if (error) + return error; + + *val *= IQS624_POS_SCALE1; + } + + *val2 = IQS624_POS_SCALE2; + return IIO_VAL_FRACTIONAL; + + default: + return -EINVAL; + } +} + +static int iqs624_pos_read_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir) +{ + struct iqs624_pos_private *iqs624_pos = iio_priv(indio_dev); + + return iqs624_pos->event_en; +} + +static int iqs624_pos_write_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + enum iio_event_type type, + enum iio_event_direction dir, + int state) +{ + struct iqs624_pos_private *iqs624_pos = iio_priv(indio_dev); + struct iqs62x_core *iqs62x = iqs624_pos->iqs62x; + int error; + + mutex_lock(&iqs624_pos->lock); + + error = regmap_update_bits(iqs62x->map, IQS624_HALL_UI, + iqs62x->dev_desc->prod_num == + IQS624_PROD_NUM ? IQS624_HALL_UI_WHL_EVENT : + IQS624_HALL_UI_INT_EVENT, + state ? 0 : 0xFF); + if (!error) + iqs624_pos->event_en = state; + + mutex_unlock(&iqs624_pos->lock); + + return error; +} + +static const struct iio_info iqs624_pos_info = { + .read_raw = &iqs624_pos_read_raw, + .read_event_config = iqs624_pos_read_event_config, + .write_event_config = iqs624_pos_write_event_config, +}; + +static const struct iio_event_spec iqs624_pos_events[] = { + { + .type = IIO_EV_TYPE_CHANGE, + .dir = IIO_EV_DIR_NONE, + .mask_separate = BIT(IIO_EV_INFO_ENABLE), + }, +}; + +static const struct iio_chan_spec iqs624_pos_channels[] = { + { + .type = IIO_ANGL, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .event_spec = iqs624_pos_events, + .num_event_specs = ARRAY_SIZE(iqs624_pos_events), + }, +}; + +static int iqs624_pos_probe(struct platform_device *pdev) +{ + struct iqs62x_core *iqs62x = dev_get_drvdata(pdev->dev.parent); + struct iqs624_pos_private *iqs624_pos; + struct iio_dev *indio_dev; + int error; + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*iqs624_pos)); + if (!indio_dev) + return -ENOMEM; + + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->dev.parent = &pdev->dev; + indio_dev->channels = iqs624_pos_channels; + indio_dev->num_channels = ARRAY_SIZE(iqs624_pos_channels); + indio_dev->name = iqs62x->dev_desc->dev_name; + indio_dev->info = &iqs624_pos_info; + + iqs624_pos = iio_priv(indio_dev); + iqs624_pos->iqs62x = iqs62x; + + mutex_init(&iqs624_pos->lock); + + error = iqs624_pos_init(iqs624_pos); + if (error) + return error; + + iqs624_pos->notifier.notifier_call = iqs624_pos_notifier; + error = blocking_notifier_chain_register(&iqs624_pos->iqs62x->nh, + &iqs624_pos->notifier); + if (error) { + dev_err(&pdev->dev, "Failed to register notifier: %d\n", error); + return error; + } + + error = devm_add_action_or_reset(&pdev->dev, + iqs624_pos_notifier_unregister, + iqs624_pos); + if (error) { + dev_err(&pdev->dev, "Failed to add action: %d\n", error); + return error; + } + + return devm_iio_device_register(&pdev->dev, indio_dev); +} + +static struct platform_driver iqs624_pos_platform_driver = { + .driver = { + .name = IQS624_DRV_NAME_POS, + }, + .probe = iqs624_pos_probe, +}; +module_platform_driver(iqs624_pos_platform_driver); + +MODULE_AUTHOR("Jeff LaBundy "); +MODULE_DESCRIPTION("Azoteq IQS624/625 Angular Position Sensor"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" IQS624_DRV_NAME_POS);