iio: proximity: vl53l0x-i2c: claim direct mode for raw readsgrafted

vl53l0x_read_raw() starts a single-shot ranging measurement and reads
back the result. Once the triggered buffer is enabled the sensor runs in
continuous mode and its data-ready interrupt is routed to the trigger,
so a concurrent in_distance_raw read disturbs the streaming setup and
never gets its completion, returning -ETIMEDOUT.

The original submission claimed direct mode here, but it was dropped
during review because the driver had no buffer support at the time [1].
Continuous (buffered) mode was later added without restoring the
claim [2], reintroducing the conflict.

Reject direct reads while buffered capture is active by claiming direct
mode around the measurement, as the vl53l1x sibling already does.

Fixes: 762186c6e7b1 ("iio: proximity: vl53l0x-i2c: Added continuous mode support")
Link: https://lore.kernel.org/linux-iio/20180911160300.GA9212@himanshu-Vostro-3559/ [1]
Link: https://lore.kernel.org/linux-iio/20240909101508.263085-3-abhashkumarjha123@gmail.com/ [2]
Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

2 files changed, 41 insertions, 0 deletions

diff --git a/Documentation/userspace-api/ebpf/index.rst b/Documentation/userspace-api/ebpf/index.rst
new file mode 100644
index 000000000..473dfba78
--- /dev/null
+++ b/Documentation/userspace-api/ebpf/index.rst
@@ -0,0 +1,17 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+eBPF Userspace API
+==================
+
+eBPF is a kernel mechanism to provide a sandboxed runtime environment in the
+Linux kernel for runtime extension and instrumentation without changing kernel
+source code or loading kernel modules. eBPF programs can be attached to various
+kernel subsystems, including networking, tracing and Linux security modules
+(LSM).
+
+For internal kernel documentation on eBPF, see Documentation/bpf/index.rst.
+
+.. toctree::
+   :maxdepth: 1
+
+   syscall
diff --git a/Documentation/userspace-api/ebpf/syscall.rst b/Documentation/userspace-api/ebpf/syscall.rst
new file mode 100644
index 000000000..ea9918084
--- /dev/null
+++ b/Documentation/userspace-api/ebpf/syscall.rst
@@ -0,0 +1,24 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+eBPF Syscall
+------------
+
+:Authors: - Alexei Starovoitov <ast@kernel.org>
+          - Joe Stringer <joe@wand.net.nz>
+          - Michael Kerrisk <mtk.manpages@gmail.com>
+
+The primary info for the bpf syscall is available in the `man-pages`_
+for `bpf(2)`_.
+
+bpf() subcommand reference
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. kernel-doc:: include/uapi/linux/bpf.h
+   :doc: eBPF Syscall Preamble
+
+.. kernel-doc:: include/uapi/linux/bpf.h
+   :doc: eBPF Syscall Commands
+
+.. Links:
+.. _man-pages: https://www.kernel.org/doc/man-pages/
+.. _bpf(2): https://man7.org/linux/man-pages/man2/bpf.2.html