From 1dae0cb79ceacbdc7495c5f83ca71e1c12a24d7c Mon Sep 17 00:00:00 2001 From: Jonathan Cameron Date: Sun, 28 Jan 2024 15:05:28 +0000 Subject: iio: locking: introduce __cleanup() based direct mode claiming infrastructure Allows use of: iio_device_claim_direct_scoped(return -EBUSY, indio_dev) { } to automatically call iio_device_release_direct_mode() based on scope. Typically seen in combination with local device specific locks which are already have automated cleanup options via guard(mutex)(&st->lock) and scoped_guard(). Using both together allows most error handling to be automated. Reviewed-by: Nuno Sa Link: https://lore.kernel.org/r/20240128150537.44592-2-jic23@kernel.org Signed-off-by: Jonathan Cameron --- include/linux/iio/iio.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'include') diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index c5b36d2c1e73..4f89279e531c 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -9,6 +9,7 @@ #include #include +#include #include #include /* IIO TODO LIST */ @@ -638,6 +639,33 @@ int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev, int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp); int iio_device_claim_direct_mode(struct iio_dev *indio_dev); void iio_device_release_direct_mode(struct iio_dev *indio_dev); + +/* + * This autocleanup logic is normally used via + * iio_device_claim_direct_scoped(). + */ +DEFINE_GUARD(iio_claim_direct, struct iio_dev *, iio_device_claim_direct_mode(_T), + iio_device_release_direct_mode(_T)) + +DEFINE_GUARD_COND(iio_claim_direct, _try, ({ + struct iio_dev *dev; + int d = iio_device_claim_direct_mode(_T); + + if (d < 0) + dev = NULL; + else + dev = _T; + dev; + })) + +/** + * iio_device_claim_direct_scoped() - Scoped call to iio_device_claim_direct. + * @fail: What to do on failure to claim device. + * @iio_dev: Pointer to the IIO devices structure + */ +#define iio_device_claim_direct_scoped(fail, iio_dev) \ + scoped_cond_guard(iio_claim_direct_try, fail, iio_dev) + int iio_device_claim_buffer_mode(struct iio_dev *indio_dev); void iio_device_release_buffer_mode(struct iio_dev *indio_dev); -- cgit v1.2.3