Message ID | 1575851866-18919-8-git-send-email-jeff@labundy.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | Add support for Azoteq IQS620A/621/622/624/625 | expand |
On Mon, 9 Dec 2019 00:38:41 +0000 Jeff LaBundy <jeff@labundy.com> wrote: > 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 <jeff@labundy.com> Looks good Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> My current assumption is that Lee will take this lot via an immutable branch in MFD once it's ready. Shout if a different path makes sense. > --- > Changes in v2: > - Merged 'Copyright' and 'Author' lines into one in introductory comments > - Replaced 'error' with 'ret' throughout > - Added iqs624_pos_angle_en and iqs624_pos_angle_get to remove duplicate > logic previously used throughout > - Refactored the logic in iqs624_pos_notifier and added a lock to safely > evaluate variables that may change in response to user action > - Refactored the logic in iqs624_pos_read_raw > - Added a lock to iqs624_pos_read_event_config to account for cases in which > the corresponding hardware state is in the process of being updated > - Refactored the logic in iqs624_pos_write_event_config and read the initial > angle in case it changed since having first been read in iqs624_pos_init > - Removed iqs624_pos_init as its logic has since been absorbed elsewhere > - Removed devm_add_action_or_reset failure message > - Eliminated tabbed alignment of platform_driver struct members > - Changed Kconfig "depends on" logic to MFD_IQS62X || COMPILE_TEST > > drivers/iio/Kconfig | 1 + > drivers/iio/Makefile | 1 + > drivers/iio/position/Kconfig | 19 +++ > drivers/iio/position/Makefile | 7 + > drivers/iio/position/iqs624-pos.c | 284 ++++++++++++++++++++++++++++++++++++++ > 5 files changed, 312 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..eda67f0 > --- /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 sensors" > + depends on MFD_IQS62X || COMPILE_TEST > + 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..af629bf5 > --- /dev/null > +++ b/drivers/iio/position/iqs624-pos.c > @@ -0,0 +1,284 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Azoteq IQS624/625 Angular Position Sensors > + * > + * Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com> > + */ > + > +#include <linux/device.h> > +#include <linux/iio/events.h> > +#include <linux/iio/iio.h> > +#include <linux/kernel.h> > +#include <linux/mfd/iqs62x.h> > +#include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/notifier.h> > +#include <linux/platform_device.h> > +#include <linux/regmap.h> > + > +#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 angle_en; > + u16 angle; > +}; > + > +static int iqs624_pos_angle_en(struct iqs62x_core *iqs62x, bool angle_en) > +{ > + unsigned int event_mask = IQS624_HALL_UI_WHL_EVENT; > + > + /* > + * 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. > + */ > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) > + event_mask = IQS624_HALL_UI_INT_EVENT; > + > + return regmap_update_bits(iqs62x->map, IQS624_HALL_UI, event_mask, > + angle_en ? 0 : 0xFF); > +} > + > +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; > + u16 angle = event_data->ui_data; > + s64 timestamp; > + int ret; > + > + iqs624_pos = container_of(notifier, struct iqs624_pos_private, > + notifier); > + indio_dev = iio_priv_to_dev(iqs624_pos); > + timestamp = iio_get_time_ns(indio_dev); > + > + iqs62x = iqs624_pos->iqs62x; > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) > + angle = event_data->interval; > + > + mutex_lock(&iqs624_pos->lock); > + > + if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) { > + ret = iqs624_pos_angle_en(iqs62x, iqs624_pos->angle_en); > + if (ret) { > + dev_err(indio_dev->dev.parent, > + "Failed to re-initialize device: %d\n", ret); > + ret = NOTIFY_BAD; > + } else { > + ret = NOTIFY_OK; > + } > + } else if (iqs624_pos->angle_en && (angle != iqs624_pos->angle)) { > + iio_push_event(indio_dev, > + IIO_UNMOD_EVENT_CODE(IIO_ANGL, 0, > + IIO_EV_TYPE_CHANGE, > + IIO_EV_DIR_NONE), > + timestamp); > + > + iqs624_pos->angle = angle; > + ret = NOTIFY_OK; > + } else { > + ret = NOTIFY_DONE; > + } > + > + mutex_unlock(&iqs624_pos->lock); > + > + return ret; > +} > + > +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 ret; > + > + ret = blocking_notifier_chain_unregister(&iqs624_pos->iqs62x->nh, > + &iqs624_pos->notifier); > + if (ret) > + dev_err(indio_dev->dev.parent, > + "Failed to unregister notifier: %d\n", ret); > +} > + > +static int iqs624_pos_angle_get(struct iqs62x_core *iqs62x, unsigned int *val) > +{ > + int ret; > + __le16 val_buf; > + > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) > + return regmap_read(iqs62x->map, iqs62x->dev_desc->interval, > + val); > + > + ret = regmap_raw_read(iqs62x->map, IQS624_POS_DEG_OUT, &val_buf, > + sizeof(val_buf)); > + if (ret) > + return ret; > + > + *val = le16_to_cpu(val_buf); > + > + return 0; > +} > + > +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; > + unsigned int scale = 1; > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + ret = iqs624_pos_angle_get(iqs62x, val); > + if (ret) > + return ret; > + > + return IIO_VAL_INT; > + > + case IIO_CHAN_INFO_SCALE: > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) { > + ret = regmap_read(iqs62x->map, IQS624_INTERVAL_DIV, > + &scale); > + if (ret) > + return ret; > + } > + > + *val = scale * 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); > + int ret; > + > + mutex_lock(&iqs624_pos->lock); > + ret = iqs624_pos->angle_en; > + mutex_unlock(&iqs624_pos->lock); > + > + return ret; > +} > + > +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; > + unsigned int val; > + int ret; > + > + mutex_lock(&iqs624_pos->lock); > + > + ret = iqs624_pos_angle_get(iqs62x, &val); > + if (ret) > + goto err_mutex; > + > + ret = iqs624_pos_angle_en(iqs62x, state); > + if (ret) > + goto err_mutex; > + > + iqs624_pos->angle = val; > + iqs624_pos->angle_en = state; > + > +err_mutex: > + mutex_unlock(&iqs624_pos->lock); > + > + return ret; > +} > + > +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 ret; > + > + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*iqs624_pos)); > + if (!indio_dev) > + return -ENOMEM; > + > + iqs624_pos = iio_priv(indio_dev); > + iqs624_pos->iqs62x = iqs62x; > + > + 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; > + > + mutex_init(&iqs624_pos->lock); > + > + iqs624_pos->notifier.notifier_call = iqs624_pos_notifier; > + ret = blocking_notifier_chain_register(&iqs624_pos->iqs62x->nh, > + &iqs624_pos->notifier); > + if (ret) { > + dev_err(&pdev->dev, "Failed to register notifier: %d\n", ret); > + return ret; > + } > + > + ret = devm_add_action_or_reset(&pdev->dev, > + iqs624_pos_notifier_unregister, > + iqs624_pos); > + if (ret) > + return ret; > + > + 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 <jeff@labundy.com>"); > +MODULE_DESCRIPTION("Azoteq IQS624/625 Angular Position Sensors"); > +MODULE_LICENSE("GPL"); > +MODULE_ALIAS("platform:" IQS624_DRV_NAME_POS); > -- > 2.7.4 >
Hi Jonathan, Thank you for your continued support on this project. On Sun, Dec 15, 2019 at 04:53:28PM +0000, Jonathan Cameron wrote: > On Mon, 9 Dec 2019 00:38:41 +0000 > Jeff LaBundy <jeff@labundy.com> wrote: > > > 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 <jeff@labundy.com> > > Looks good > > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > My current assumption is that Lee will take this lot via an immutable branch > in MFD once it's ready. Shout if a different path makes sense. Same here. @Lee, please let us know if you disagree. > > --- > > Changes in v2: > > - Merged 'Copyright' and 'Author' lines into one in introductory comments > > - Replaced 'error' with 'ret' throughout > > - Added iqs624_pos_angle_en and iqs624_pos_angle_get to remove duplicate > > logic previously used throughout > > - Refactored the logic in iqs624_pos_notifier and added a lock to safely > > evaluate variables that may change in response to user action > > - Refactored the logic in iqs624_pos_read_raw > > - Added a lock to iqs624_pos_read_event_config to account for cases in which > > the corresponding hardware state is in the process of being updated > > - Refactored the logic in iqs624_pos_write_event_config and read the initial > > angle in case it changed since having first been read in iqs624_pos_init > > - Removed iqs624_pos_init as its logic has since been absorbed elsewhere > > - Removed devm_add_action_or_reset failure message > > - Eliminated tabbed alignment of platform_driver struct members > > - Changed Kconfig "depends on" logic to MFD_IQS62X || COMPILE_TEST > > > > drivers/iio/Kconfig | 1 + > > drivers/iio/Makefile | 1 + > > drivers/iio/position/Kconfig | 19 +++ > > drivers/iio/position/Makefile | 7 + > > drivers/iio/position/iqs624-pos.c | 284 ++++++++++++++++++++++++++++++++++++++ > > 5 files changed, 312 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..eda67f0 > > --- /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 sensors" > > + depends on MFD_IQS62X || COMPILE_TEST > > + 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..af629bf5 > > --- /dev/null > > +++ b/drivers/iio/position/iqs624-pos.c > > @@ -0,0 +1,284 @@ > > +// SPDX-License-Identifier: GPL-2.0+ > > +/* > > + * Azoteq IQS624/625 Angular Position Sensors > > + * > > + * Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com> > > + */ > > + > > +#include <linux/device.h> > > +#include <linux/iio/events.h> > > +#include <linux/iio/iio.h> > > +#include <linux/kernel.h> > > +#include <linux/mfd/iqs62x.h> > > +#include <linux/module.h> > > +#include <linux/mutex.h> > > +#include <linux/notifier.h> > > +#include <linux/platform_device.h> > > +#include <linux/regmap.h> > > + > > +#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 angle_en; > > + u16 angle; > > +}; > > + > > +static int iqs624_pos_angle_en(struct iqs62x_core *iqs62x, bool angle_en) > > +{ > > + unsigned int event_mask = IQS624_HALL_UI_WHL_EVENT; > > + > > + /* > > + * 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. > > + */ > > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) > > + event_mask = IQS624_HALL_UI_INT_EVENT; > > + > > + return regmap_update_bits(iqs62x->map, IQS624_HALL_UI, event_mask, > > + angle_en ? 0 : 0xFF); > > +} > > + > > +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; > > + u16 angle = event_data->ui_data; > > + s64 timestamp; > > + int ret; > > + > > + iqs624_pos = container_of(notifier, struct iqs624_pos_private, > > + notifier); > > + indio_dev = iio_priv_to_dev(iqs624_pos); > > + timestamp = iio_get_time_ns(indio_dev); > > + > > + iqs62x = iqs624_pos->iqs62x; > > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) > > + angle = event_data->interval; > > + > > + mutex_lock(&iqs624_pos->lock); > > + > > + if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) { > > + ret = iqs624_pos_angle_en(iqs62x, iqs624_pos->angle_en); > > + if (ret) { > > + dev_err(indio_dev->dev.parent, > > + "Failed to re-initialize device: %d\n", ret); > > + ret = NOTIFY_BAD; > > + } else { > > + ret = NOTIFY_OK; > > + } > > + } else if (iqs624_pos->angle_en && (angle != iqs624_pos->angle)) { > > + iio_push_event(indio_dev, > > + IIO_UNMOD_EVENT_CODE(IIO_ANGL, 0, > > + IIO_EV_TYPE_CHANGE, > > + IIO_EV_DIR_NONE), > > + timestamp); > > + > > + iqs624_pos->angle = angle; > > + ret = NOTIFY_OK; > > + } else { > > + ret = NOTIFY_DONE; > > + } > > + > > + mutex_unlock(&iqs624_pos->lock); > > + > > + return ret; > > +} > > + > > +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 ret; > > + > > + ret = blocking_notifier_chain_unregister(&iqs624_pos->iqs62x->nh, > > + &iqs624_pos->notifier); > > + if (ret) > > + dev_err(indio_dev->dev.parent, > > + "Failed to unregister notifier: %d\n", ret); > > +} > > + > > +static int iqs624_pos_angle_get(struct iqs62x_core *iqs62x, unsigned int *val) > > +{ > > + int ret; > > + __le16 val_buf; > > + > > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) > > + return regmap_read(iqs62x->map, iqs62x->dev_desc->interval, > > + val); > > + > > + ret = regmap_raw_read(iqs62x->map, IQS624_POS_DEG_OUT, &val_buf, > > + sizeof(val_buf)); > > + if (ret) > > + return ret; > > + > > + *val = le16_to_cpu(val_buf); > > + > > + return 0; > > +} > > + > > +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; > > + unsigned int scale = 1; > > + int ret; > > + > > + switch (mask) { > > + case IIO_CHAN_INFO_RAW: > > + ret = iqs624_pos_angle_get(iqs62x, val); > > + if (ret) > > + return ret; > > + > > + return IIO_VAL_INT; > > + > > + case IIO_CHAN_INFO_SCALE: > > + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) { > > + ret = regmap_read(iqs62x->map, IQS624_INTERVAL_DIV, > > + &scale); > > + if (ret) > > + return ret; > > + } > > + > > + *val = scale * 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); > > + int ret; > > + > > + mutex_lock(&iqs624_pos->lock); > > + ret = iqs624_pos->angle_en; > > + mutex_unlock(&iqs624_pos->lock); > > + > > + return ret; > > +} > > + > > +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; > > + unsigned int val; > > + int ret; > > + > > + mutex_lock(&iqs624_pos->lock); > > + > > + ret = iqs624_pos_angle_get(iqs62x, &val); > > + if (ret) > > + goto err_mutex; > > + > > + ret = iqs624_pos_angle_en(iqs62x, state); > > + if (ret) > > + goto err_mutex; > > + > > + iqs624_pos->angle = val; > > + iqs624_pos->angle_en = state; > > + > > +err_mutex: > > + mutex_unlock(&iqs624_pos->lock); > > + > > + return ret; > > +} > > + > > +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 ret; > > + > > + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*iqs624_pos)); > > + if (!indio_dev) > > + return -ENOMEM; > > + > > + iqs624_pos = iio_priv(indio_dev); > > + iqs624_pos->iqs62x = iqs62x; > > + > > + 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; > > + > > + mutex_init(&iqs624_pos->lock); > > + > > + iqs624_pos->notifier.notifier_call = iqs624_pos_notifier; > > + ret = blocking_notifier_chain_register(&iqs624_pos->iqs62x->nh, > > + &iqs624_pos->notifier); > > + if (ret) { > > + dev_err(&pdev->dev, "Failed to register notifier: %d\n", ret); > > + return ret; > > + } > > + > > + ret = devm_add_action_or_reset(&pdev->dev, > > + iqs624_pos_notifier_unregister, > > + iqs624_pos); > > + if (ret) > > + return ret; > > + > > + 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 <jeff@labundy.com>"); > > +MODULE_DESCRIPTION("Azoteq IQS624/625 Angular Position Sensors"); > > +MODULE_LICENSE("GPL"); > > +MODULE_ALIAS("platform:" IQS624_DRV_NAME_POS); > > -- > > 2.7.4 > > > Wishing you a Happy New Year, Jeff LaBundy
On Wed, 01 Jan 2020, Jeff LaBundy wrote: > Hi Jonathan, > > Thank you for your continued support on this project. > > On Sun, Dec 15, 2019 at 04:53:28PM +0000, Jonathan Cameron wrote: > > On Mon, 9 Dec 2019 00:38:41 +0000 > > Jeff LaBundy <jeff@labundy.com> wrote: > > > > > 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 <jeff@labundy.com> > > > > Looks good > > > > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > > > My current assumption is that Lee will take this lot via an immutable branch > > in MFD once it's ready. Shout if a different path makes sense. > > Same here. @Lee, please let us know if you disagree. That's fine.
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..eda67f0 --- /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 sensors" + depends on MFD_IQS62X || COMPILE_TEST + 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..af629bf5 --- /dev/null +++ b/drivers/iio/position/iqs624-pos.c @@ -0,0 +1,284 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Azoteq IQS624/625 Angular Position Sensors + * + * Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com> + */ + +#include <linux/device.h> +#include <linux/iio/events.h> +#include <linux/iio/iio.h> +#include <linux/kernel.h> +#include <linux/mfd/iqs62x.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/notifier.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#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 angle_en; + u16 angle; +}; + +static int iqs624_pos_angle_en(struct iqs62x_core *iqs62x, bool angle_en) +{ + unsigned int event_mask = IQS624_HALL_UI_WHL_EVENT; + + /* + * 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. + */ + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) + event_mask = IQS624_HALL_UI_INT_EVENT; + + return regmap_update_bits(iqs62x->map, IQS624_HALL_UI, event_mask, + angle_en ? 0 : 0xFF); +} + +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; + u16 angle = event_data->ui_data; + s64 timestamp; + int ret; + + iqs624_pos = container_of(notifier, struct iqs624_pos_private, + notifier); + indio_dev = iio_priv_to_dev(iqs624_pos); + timestamp = iio_get_time_ns(indio_dev); + + iqs62x = iqs624_pos->iqs62x; + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) + angle = event_data->interval; + + mutex_lock(&iqs624_pos->lock); + + if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) { + ret = iqs624_pos_angle_en(iqs62x, iqs624_pos->angle_en); + if (ret) { + dev_err(indio_dev->dev.parent, + "Failed to re-initialize device: %d\n", ret); + ret = NOTIFY_BAD; + } else { + ret = NOTIFY_OK; + } + } else if (iqs624_pos->angle_en && (angle != iqs624_pos->angle)) { + iio_push_event(indio_dev, + IIO_UNMOD_EVENT_CODE(IIO_ANGL, 0, + IIO_EV_TYPE_CHANGE, + IIO_EV_DIR_NONE), + timestamp); + + iqs624_pos->angle = angle; + ret = NOTIFY_OK; + } else { + ret = NOTIFY_DONE; + } + + mutex_unlock(&iqs624_pos->lock); + + return ret; +} + +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 ret; + + ret = blocking_notifier_chain_unregister(&iqs624_pos->iqs62x->nh, + &iqs624_pos->notifier); + if (ret) + dev_err(indio_dev->dev.parent, + "Failed to unregister notifier: %d\n", ret); +} + +static int iqs624_pos_angle_get(struct iqs62x_core *iqs62x, unsigned int *val) +{ + int ret; + __le16 val_buf; + + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) + return regmap_read(iqs62x->map, iqs62x->dev_desc->interval, + val); + + ret = regmap_raw_read(iqs62x->map, IQS624_POS_DEG_OUT, &val_buf, + sizeof(val_buf)); + if (ret) + return ret; + + *val = le16_to_cpu(val_buf); + + return 0; +} + +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; + unsigned int scale = 1; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = iqs624_pos_angle_get(iqs62x, val); + if (ret) + return ret; + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) { + ret = regmap_read(iqs62x->map, IQS624_INTERVAL_DIV, + &scale); + if (ret) + return ret; + } + + *val = scale * 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); + int ret; + + mutex_lock(&iqs624_pos->lock); + ret = iqs624_pos->angle_en; + mutex_unlock(&iqs624_pos->lock); + + return ret; +} + +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; + unsigned int val; + int ret; + + mutex_lock(&iqs624_pos->lock); + + ret = iqs624_pos_angle_get(iqs62x, &val); + if (ret) + goto err_mutex; + + ret = iqs624_pos_angle_en(iqs62x, state); + if (ret) + goto err_mutex; + + iqs624_pos->angle = val; + iqs624_pos->angle_en = state; + +err_mutex: + mutex_unlock(&iqs624_pos->lock); + + return ret; +} + +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 ret; + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*iqs624_pos)); + if (!indio_dev) + return -ENOMEM; + + iqs624_pos = iio_priv(indio_dev); + iqs624_pos->iqs62x = iqs62x; + + 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; + + mutex_init(&iqs624_pos->lock); + + iqs624_pos->notifier.notifier_call = iqs624_pos_notifier; + ret = blocking_notifier_chain_register(&iqs624_pos->iqs62x->nh, + &iqs624_pos->notifier); + if (ret) { + dev_err(&pdev->dev, "Failed to register notifier: %d\n", ret); + return ret; + } + + ret = devm_add_action_or_reset(&pdev->dev, + iqs624_pos_notifier_unregister, + iqs624_pos); + if (ret) + return ret; + + 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 <jeff@labundy.com>"); +MODULE_DESCRIPTION("Azoteq IQS624/625 Angular Position Sensors"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" IQS624_DRV_NAME_POS);
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 <jeff@labundy.com> --- Changes in v2: - Merged 'Copyright' and 'Author' lines into one in introductory comments - Replaced 'error' with 'ret' throughout - Added iqs624_pos_angle_en and iqs624_pos_angle_get to remove duplicate logic previously used throughout - Refactored the logic in iqs624_pos_notifier and added a lock to safely evaluate variables that may change in response to user action - Refactored the logic in iqs624_pos_read_raw - Added a lock to iqs624_pos_read_event_config to account for cases in which the corresponding hardware state is in the process of being updated - Refactored the logic in iqs624_pos_write_event_config and read the initial angle in case it changed since having first been read in iqs624_pos_init - Removed iqs624_pos_init as its logic has since been absorbed elsewhere - Removed devm_add_action_or_reset failure message - Eliminated tabbed alignment of platform_driver struct members - Changed Kconfig "depends on" logic to MFD_IQS62X || COMPILE_TEST drivers/iio/Kconfig | 1 + drivers/iio/Makefile | 1 + drivers/iio/position/Kconfig | 19 +++ drivers/iio/position/Makefile | 7 + drivers/iio/position/iqs624-pos.c | 284 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 312 insertions(+) create mode 100644 drivers/iio/position/Kconfig create mode 100644 drivers/iio/position/Makefile create mode 100644 drivers/iio/position/iqs624-pos.c -- 2.7.4