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>

1 files changed, 132 insertions, 0 deletions

diff --git a/Documentation/crypto/sha3.rst b/Documentation/crypto/sha3.rst
new file mode 100644
index 000000000..250669c98
--- /dev/null
+++ b/Documentation/crypto/sha3.rst
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+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+.. _sha3:
+
+==========================
+SHA-3 Algorithm Collection
+==========================
+
+.. contents::
+
+Overview
+========
+
+The SHA-3 family of algorithms, as specified in NIST FIPS-202 [1]_, contains six
+algorithms based on the Keccak sponge function.  The differences between them
+are: the "rate" (how much of the state buffer gets updated with new data between
+invocations of the Keccak function and analogous to the "block size"), what
+domain separation suffix gets appended to the input data, and how much output
+data is extracted at the end.  The Keccak sponge function is designed such that
+arbitrary amounts of output can be obtained for certain algorithms.
+
+Four digest algorithms are provided:
+
+ - SHA3-224
+ - SHA3-256
+ - SHA3-384
+ - SHA3-512
+
+Additionally, two Extendable-Output Functions (XOFs) are provided:
+
+ - SHAKE128
+ - SHAKE256
+
+The SHA-3 library API supports all six of these algorithms.  The four digest
+algorithms are also supported by the crypto_shash and crypto_ahash APIs.
+
+This document describes the SHA-3 library API.
+
+
+Digests
+=======
+
+The following functions compute SHA-3 digests::
+
+	void sha3_224(const u8 *in, size_t in_len, u8 out[SHA3_224_DIGEST_SIZE]);
+	void sha3_256(const u8 *in, size_t in_len, u8 out[SHA3_256_DIGEST_SIZE]);
+	void sha3_384(const u8 *in, size_t in_len, u8 out[SHA3_384_DIGEST_SIZE]);
+	void sha3_512(const u8 *in, size_t in_len, u8 out[SHA3_512_DIGEST_SIZE]);
+
+For users that need to pass in data incrementally, an incremental API is also
+provided.  The incremental API uses the following struct::
+
+	struct sha3_ctx { ... };
+
+Initialization is done with one of::
+
+	void sha3_224_init(struct sha3_ctx *ctx);
+	void sha3_256_init(struct sha3_ctx *ctx);
+	void sha3_384_init(struct sha3_ctx *ctx);
+	void sha3_512_init(struct sha3_ctx *ctx);
+
+Input data is then added with any number of calls to::
+
+	void sha3_update(struct sha3_ctx *ctx, const u8 *in, size_t in_len);
+
+Finally, the digest is generated using::
+
+	void sha3_final(struct sha3_ctx *ctx, u8 *out);
+
+which also zeroizes the context.  The length of the digest is determined by the
+initialization function that was called.
+
+
+Extendable-Output Functions
+===========================
+
+The following functions compute the SHA-3 extendable-output functions (XOFs)::
+
+	void shake128(const u8 *in, size_t in_len, u8 *out, size_t out_len);
+	void shake256(const u8 *in, size_t in_len, u8 *out, size_t out_len);
+
+For users that need to provide the input data incrementally and/or receive the
+output data incrementally, an incremental API is also provided.  The incremental
+API uses the following struct::
+
+	struct shake_ctx { ... };
+
+Initialization is done with one of::
+
+	void shake128_init(struct shake_ctx *ctx);
+	void shake256_init(struct shake_ctx *ctx);
+
+Input data is then added with any number of calls to::
+
+	void shake_update(struct shake_ctx *ctx, const u8 *in, size_t in_len);
+
+Finally, the output data is extracted with any number of calls to::
+
+	void shake_squeeze(struct shake_ctx *ctx, u8 *out, size_t out_len);
+
+and telling it how much data should be extracted.  Note that performing multiple
+squeezes, with the output laid consecutively in a buffer, gets exactly the same
+output as doing a single squeeze for the combined amount over the same buffer.
+
+More input data cannot be added after squeezing has started.
+
+Once all the desired output has been extracted, zeroize the context::
+
+	void shake_zeroize_ctx(struct shake_ctx *ctx);
+
+
+Testing
+=======
+
+To test the SHA-3 code, use sha3_kunit (CONFIG_CRYPTO_LIB_SHA3_KUNIT_TEST).
+
+Since the SHA-3 algorithms are FIPS-approved, when the kernel is booted in FIPS
+mode the SHA-3 library also performs a simple self-test.  This is purely to meet
+a FIPS requirement.  Normal testing done by kernel developers and integrators
+should use the much more comprehensive KUnit test suite instead.
+
+
+References
+==========
+
+.. [1] https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.202.pdf
+
+
+API Function Reference
+======================
+
+.. kernel-doc:: include/crypto/sha3.h