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- /* SPDX-License-Identifier: BSD-3-Clause
- * Copyright 2016-2018 NXP
- * Copyright (c) 2018-2019, Vladimir Oltean <[email protected]>
- */
- #ifndef _LINUX_PACKING_H
- #define _LINUX_PACKING_H
- #include <linux/types.h>
- #include <linux/bitops.h>
- #define QUIRK_MSB_ON_THE_RIGHT BIT(0)
- #define QUIRK_LITTLE_ENDIAN BIT(1)
- #define QUIRK_LSW32_IS_FIRST BIT(2)
- enum packing_op {
- PACK,
- UNPACK,
- };
- /**
- * packing - Convert numbers (currently u64) between a packed and an unpacked
- * format. Unpacked means laid out in memory in the CPU's native
- * understanding of integers, while packed means anything else that
- * requires translation.
- *
- * @pbuf: Pointer to a buffer holding the packed value.
- * @uval: Pointer to an u64 holding the unpacked value.
- * @startbit: The index (in logical notation, compensated for quirks) where
- * the packed value starts within pbuf. Must be larger than, or
- * equal to, endbit.
- * @endbit: The index (in logical notation, compensated for quirks) where
- * the packed value ends within pbuf. Must be smaller than, or equal
- * to, startbit.
- * @op: If PACK, then uval will be treated as const pointer and copied (packed)
- * into pbuf, between startbit and endbit.
- * If UNPACK, then pbuf will be treated as const pointer and the logical
- * value between startbit and endbit will be copied (unpacked) to uval.
- * @quirks: A bit mask of QUIRK_LITTLE_ENDIAN, QUIRK_LSW32_IS_FIRST and
- * QUIRK_MSB_ON_THE_RIGHT.
- *
- * Return: 0 on success, EINVAL or ERANGE if called incorrectly. Assuming
- * correct usage, return code may be discarded.
- * If op is PACK, pbuf is modified.
- * If op is UNPACK, uval is modified.
- */
- int packing(void *pbuf, u64 *uval, int startbit, int endbit, size_t pbuflen,
- enum packing_op op, u8 quirks);
- #endif
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