From 88fd1f90792411226f49e5f285bf3faca5ac970b Mon Sep 17 00:00:00 2001 From: Kurt Borja Date: Tue, 20 Jan 2026 01:20:41 -0500 Subject: [PATCH] iio: core: Add and export __iio_dev_mode_lock() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Add unconditional wrappers around the internal IIO mode lock. As mentioned in the documentation, this is not meant to be used by drivers, instead this will aid in the eventual addition of cleanup classes around conditional locks. Reviewed-by: David Lechner Reviewed-by: Nuno Sá Signed-off-by: Kurt Borja Signed-off-by: Jonathan Cameron --- drivers/iio/industrialio-core.c | 30 ++++++++++++++++++++++++++++++ include/linux/iio/iio.h | 3 +++ 2 files changed, 33 insertions(+) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index f69deefcfb6fd..db803267df6ed 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -2171,6 +2171,36 @@ int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev, } EXPORT_SYMBOL_GPL(__devm_iio_device_register); +/** + * __iio_dev_mode_lock() - Locks the current IIO device mode + * @indio_dev: the iio_dev associated with the device + * + * If the device is either in direct or buffer mode, it's guaranteed to stay + * that way until __iio_dev_mode_unlock() is called. + * + * This function is not meant to be used directly by drivers to protect internal + * state; a driver should have it's own mechanisms for that matter. + * + * There are very few cases where a driver actually needs to lock the current + * mode unconditionally. It's recommended to use iio_device_claim_direct() or + * iio_device_claim_buffer_mode() pairs or related helpers instead. + */ +void __iio_dev_mode_lock(struct iio_dev *indio_dev) +{ + mutex_lock(&to_iio_dev_opaque(indio_dev)->mlock); +} +EXPORT_SYMBOL_GPL(__iio_dev_mode_lock); + +/** + * __iio_dev_mode_unlock() - Unlocks the current IIO device mode + * @indio_dev: the iio_dev associated with the device + */ +void __iio_dev_mode_unlock(struct iio_dev *indio_dev) +{ + mutex_unlock(&to_iio_dev_opaque(indio_dev)->mlock); +} +EXPORT_SYMBOL_GPL(__iio_dev_mode_unlock); + /** * __iio_device_claim_direct - Keep device in direct mode * @indio_dev: the iio_dev associated with the device diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index 872ebdf0dd77a..aecda887d8337 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -661,6 +661,9 @@ void iio_device_unregister(struct iio_dev *indio_dev); int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev, struct module *this_mod); int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp); + +void __iio_dev_mode_lock(struct iio_dev *indio_dev) __acquires(indio_dev); +void __iio_dev_mode_unlock(struct iio_dev *indio_dev) __releases(indio_dev); bool __iio_device_claim_direct(struct iio_dev *indio_dev); void __iio_device_release_direct(struct iio_dev *indio_dev); -- 2.47.3