linux/drivers/media/platform/mtk-jpeg/mtk_jpeg_parse.c

161 lines
3.1 KiB
C

/*
* Copyright (c) 2016 MediaTek Inc.
* Author: Ming Hsiu Tsai <minghsiu.tsai@mediatek.com>
* Rick Chang <rick.chang@mediatek.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/videodev2.h>
#include "mtk_jpeg_parse.h"
#define TEM 0x01
#define SOF0 0xc0
#define RST 0xd0
#define SOI 0xd8
#define EOI 0xd9
struct mtk_jpeg_stream {
u8 *addr;
u32 size;
u32 curr;
};
static int read_byte(struct mtk_jpeg_stream *stream)
{
if (stream->curr >= stream->size)
return -1;
return stream->addr[stream->curr++];
}
static int read_word_be(struct mtk_jpeg_stream *stream, u32 *word)
{
u32 temp;
int byte;
byte = read_byte(stream);
if (byte == -1)
return -1;
temp = byte << 8;
byte = read_byte(stream);
if (byte == -1)
return -1;
*word = (u32)byte | temp;
return 0;
}
static void read_skip(struct mtk_jpeg_stream *stream, long len)
{
if (len <= 0)
return;
while (len--)
read_byte(stream);
}
static bool mtk_jpeg_do_parse(struct mtk_jpeg_dec_param *param, u8 *src_addr_va,
u32 src_size)
{
bool notfound = true;
struct mtk_jpeg_stream stream;
stream.addr = src_addr_va;
stream.size = src_size;
stream.curr = 0;
while (notfound) {
int i, length, byte;
u32 word;
byte = read_byte(&stream);
if (byte == -1)
return false;
if (byte != 0xff)
continue;
do
byte = read_byte(&stream);
while (byte == 0xff);
if (byte == -1)
return false;
if (byte == 0)
continue;
length = 0;
switch (byte) {
case SOF0:
/* length */
if (read_word_be(&stream, &word))
break;
/* precision */
if (read_byte(&stream) == -1)
break;
if (read_word_be(&stream, &word))
break;
param->pic_h = word;
if (read_word_be(&stream, &word))
break;
param->pic_w = word;
param->comp_num = read_byte(&stream);
if (param->comp_num != 1 && param->comp_num != 3)
break;
for (i = 0; i < param->comp_num; i++) {
param->comp_id[i] = read_byte(&stream);
if (param->comp_id[i] == -1)
break;
/* sampling */
byte = read_byte(&stream);
if (byte == -1)
break;
param->sampling_w[i] = (byte >> 4) & 0x0F;
param->sampling_h[i] = byte & 0x0F;
param->qtbl_num[i] = read_byte(&stream);
if (param->qtbl_num[i] == -1)
break;
}
notfound = !(i == param->comp_num);
break;
case RST ... RST + 7:
case SOI:
case EOI:
case TEM:
break;
default:
if (read_word_be(&stream, &word))
break;
length = (long)word - 2;
read_skip(&stream, length);
break;
}
}
return !notfound;
}
bool mtk_jpeg_parse(struct mtk_jpeg_dec_param *param, u8 *src_addr_va,
u32 src_size)
{
if (!mtk_jpeg_do_parse(param, src_addr_va, src_size))
return false;
if (mtk_jpeg_dec_fill_param(param))
return false;
return true;
}