linux-stable/include/linux/ascii85.h
Jordan Crouse 489cae632f include: Move ascii85 functions from i915 to linux/ascii85.h
The i915 DRM driver very cleverly used ascii85 encoding for their
GPU state file. Move the encode functions to a general header file to
support other drivers that might be interested in the same
functionality.

v4: Make the return value const char * as suggested by Chris Wilson
v3: Fix error_puts -> err_puts pointed out by the 01.org bot
v2: Update API to be cleaner for the caller as suggested by Chris Wilson

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
2018-07-30 08:49:02 -04:00

38 lines
532 B
C

/*
* SPDX-License-Identifier: GPL-2.0
*
* Copyright (c) 2008 Intel Corporation
* Copyright (c) 2018 The Linux Foundation. All rights reserved.
*/
#ifndef _ASCII85_H_
#define _ASCII85_H_
#include <linux/kernel.h>
#define ASCII85_BUFSZ 6
static inline long
ascii85_encode_len(long len)
{
return DIV_ROUND_UP(len, 4);
}
static inline const char *
ascii85_encode(u32 in, char *out)
{
int i;
if (in == 0)
return "z";
out[5] = '\0';
for (i = 5; i--; ) {
out[i] = '!' + in % 85;
in /= 85;
}
return out;
}
#endif