--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * V4L2 JPEG header parser helpers.
+ *
+ * Copyright (C) 2019 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
+ *
+ * For reference, see JPEG ITU-T.81 (ISO/IEC 10918-1) [1]
+ *
+ * [1] https://www.w3.org/Graphics/JPEG/itu-t81.pdf
+ */
+
+#include <asm/unaligned.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <media/v4l2-jpeg.h>
+
+MODULE_DESCRIPTION("V4L2 JPEG header parser helpers");
+MODULE_AUTHOR("Philipp Zabel <kernel@pengutronix.de>");
+MODULE_LICENSE("GPL");
+
+/* Table B.1 - Marker code assignments */
+#define SOF0 0xffc0 /* start of frame */
+#define SOF1 0xffc1
+#define SOF2 0xffc2
+#define SOF3 0xffc3
+#define SOF5 0xffc5
+#define SOF7 0xffc7
+#define JPG 0xffc8 /* extensions */
+#define SOF9 0xffc9
+#define SOF11 0xffcb
+#define SOF13 0xffcd
+#define SOF15 0xffcf
+#define DHT 0xffc4 /* huffman table */
+#define DAC 0xffcc /* arithmetic coding conditioning */
+#define RST0 0xffd0 /* restart */
+#define RST7 0xffd7
+#define SOI 0xffd8 /* start of image */
+#define EOI 0xffd9 /* end of image */
+#define SOS 0xffda /* start of stream */
+#define DQT 0xffdb /* quantization table */
+#define DNL 0xffdc /* number of lines */
+#define DRI 0xffdd /* restart interval */
+#define DHP 0xffde /* hierarchical progression */
+#define EXP 0xffdf /* expand reference */
+#define APP0 0xffe0 /* application data */
+#define APP15 0xffef
+#define JPG0 0xfff0 /* extensions */
+#define JPG13 0xfffd
+#define COM 0xfffe /* comment */
+#define TEM 0xff01 /* temporary */
+
+/**
+ * struct jpeg_stream - JPEG byte stream
+ * @curr: current position in stream
+ * @end: end position, after last byte
+ */
+struct jpeg_stream {
+ u8 *curr;
+ u8 *end;
+};
+
+/* returns a value that fits into u8, or negative error */
+static int jpeg_get_byte(struct jpeg_stream *stream)
+{
+ if (stream->curr >= stream->end)
+ return -EINVAL;
+
+ return *stream->curr++;
+}
+
+/* returns a value that fits into u16, or negative error */
+static int jpeg_get_word_be(struct jpeg_stream *stream)
+{
+ u16 word;
+
+ if (stream->curr + sizeof(__be16) > stream->end)
+ return -EINVAL;
+
+ word = get_unaligned_be16(stream->curr);
+ stream->curr += sizeof(__be16);
+
+ return word;
+}
+
+static int jpeg_skip(struct jpeg_stream *stream, size_t len)
+{
+ if (stream->curr + len > stream->end)
+ return -EINVAL;
+
+ stream->curr += len;
+
+ return 0;
+}
+
+static int jpeg_next_marker(struct jpeg_stream *stream)
+{
+ int byte;
+ u16 marker = 0;
+
+ while ((byte = jpeg_get_byte(stream)) >= 0) {
+ marker = (marker << 8) | byte;
+ /* skip stuffing bytes and REServed markers */
+ if (marker == TEM || (marker > 0xffbf && marker < 0xffff))
+ return marker;
+ }
+
+ return byte;
+}
+
+/* this does not advance the current position in the stream */
+static int jpeg_reference_segment(struct jpeg_stream *stream,
+ struct v4l2_jpeg_reference *segment)
+{
+ u16 len;
+
+ if (stream->curr + sizeof(__be16) > stream->end)
+ return -EINVAL;
+
+ len = get_unaligned_be16(stream->curr);
+ if (stream->curr + len > stream->end)
+ return -EINVAL;
+
+ segment->start = stream->curr;
+ segment->length = len;
+
+ return 0;
+}
+
+static int v4l2_jpeg_decode_subsampling(u8 nf, u8 h_v)
+{
+ if (nf == 1)
+ return V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY;
+
+ /* no chroma subsampling for 4-component images */
+ if (nf == 4 && h_v != 0x11)
+ return -EINVAL;
+
+ switch (h_v) {
+ case 0x11:
+ return V4L2_JPEG_CHROMA_SUBSAMPLING_444;
+ case 0x21:
+ return V4L2_JPEG_CHROMA_SUBSAMPLING_422;
+ case 0x22:
+ return V4L2_JPEG_CHROMA_SUBSAMPLING_420;
+ case 0x41:
+ return V4L2_JPEG_CHROMA_SUBSAMPLING_411;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int jpeg_parse_frame_header(struct jpeg_stream *stream, u16 sof_marker,
+ struct v4l2_jpeg_frame_header *frame_header)
+{
+ int len = jpeg_get_word_be(stream);
+
+ if (len < 0)
+ return len;
+ /* Lf = 8 + 3 * Nf, Nf >= 1 */
+ if (len < 8 + 3)
+ return -EINVAL;
+
+ if (frame_header) {
+ /* Table B.2 - Frame header parameter sizes and values */
+ int p, y, x, nf;
+ int i;
+
+ p = jpeg_get_byte(stream);
+ if (p < 0)
+ return p;
+ /*
+ * Baseline DCT only supports 8-bit precision.
+ * Extended sequential DCT also supports 12-bit precision.
+ */
+ if (p != 8 && (p != 12 || sof_marker != SOF1))
+ return -EINVAL;
+
+ y = jpeg_get_word_be(stream);
+ if (y < 0)
+ return y;
+ if (y == 0)
+ return -EINVAL;
+
+ x = jpeg_get_word_be(stream);
+ if (x < 0)
+ return x;
+ if (x == 0)
+ return -EINVAL;
+
+ nf = jpeg_get_byte(stream);
+ if (nf < 0)
+ return nf;
+ /*
+ * The spec allows 1 <= Nf <= 255, but we only support up to 4
+ * components.
+ */
+ if (nf < 1 || nf > V4L2_JPEG_MAX_COMPONENTS)
+ return -EINVAL;
+ if (len != 8 + 3 * nf)
+ return -EINVAL;
+
+ frame_header->precision = p;
+ frame_header->height = y;
+ frame_header->width = x;
+ frame_header->num_components = nf;
+
+ for (i = 0; i < nf; i++) {
+ struct v4l2_jpeg_frame_component_spec *component;
+ int c, h_v, tq;
+
+ c = jpeg_get_byte(stream);
+ if (c < 0)
+ return c;
+
+ h_v = jpeg_get_byte(stream);
+ if (h_v < 0)
+ return h_v;
+ if (i == 0) {
+ int subs;
+
+ subs = v4l2_jpeg_decode_subsampling(nf, h_v);
+ if (subs < 0)
+ return subs;
+ frame_header->subsampling = subs;
+ } else if (h_v != 0x11) {
+ /* all chroma sampling factors must be 1 */
+ return -EINVAL;
+ }
+
+ tq = jpeg_get_byte(stream);
+ if (tq < 0)
+ return tq;
+
+ component = &frame_header->component[i];
+ component->component_identifier = c;
+ component->horizontal_sampling_factor =
+ (h_v >> 4) & 0xf;
+ component->vertical_sampling_factor = h_v & 0xf;
+ component->quantization_table_selector = tq;
+ }
+ } else {
+ return jpeg_skip(stream, len - 2);
+ }
+
+ return 0;
+}
+
+static int jpeg_parse_scan_header(struct jpeg_stream *stream,
+ struct v4l2_jpeg_scan_header *scan_header)
+{
+ size_t skip;
+ int len = jpeg_get_word_be(stream);
+
+ if (len < 0)
+ return len;
+ /* Ls = 8 + 3 * Ns, Ns >= 1 */
+ if (len < 6 + 2)
+ return -EINVAL;
+
+ if (scan_header) {
+ int ns;
+ int i;
+
+ ns = jpeg_get_byte(stream);
+ if (ns < 0)
+ return ns;
+ if (ns < 1 || ns > 4 || len != 6 + 2 * ns)
+ return -EINVAL;
+
+ scan_header->num_components = ns;
+
+ for (i = 0; i < ns; i++) {
+ struct v4l2_jpeg_scan_component_spec *component;
+ int cs, td_ta;
+
+ cs = jpeg_get_byte(stream);
+ if (cs < 0)
+ return cs;
+
+ td_ta = jpeg_get_byte(stream);
+ if (td_ta < 0)
+ return td_ta;
+
+ component = &scan_header->component[i];
+ component->component_selector = cs;
+ component->dc_entropy_coding_table_selector =
+ (td_ta >> 4) & 0xf;
+ component->ac_entropy_coding_table_selector =
+ td_ta & 0xf;
+ }
+
+ skip = 3; /* skip Ss, Se, Ah, and Al */
+ } else {
+ skip = len - 2;
+ }
+
+ return jpeg_skip(stream, skip);
+}
+
+/* B.2.4.1 Quantization table-specification syntax */
+static int jpeg_parse_quantization_tables(struct jpeg_stream *stream,
+ u8 precision,
+ struct v4l2_jpeg_reference *tables)
+{
+ int len = jpeg_get_word_be(stream);
+
+ if (len < 0)
+ return len;
+ /* Lq = 2 + n * 65 (for baseline DCT), n >= 1 */
+ if (len < 2 + 65)
+ return -EINVAL;
+
+ len -= 2;
+ while (len >= 65) {
+ u8 pq, tq, *qk;
+ int ret;
+ int pq_tq = jpeg_get_byte(stream);
+
+ if (pq_tq < 0)
+ return pq_tq;
+
+ /* quantization table element precision */
+ pq = (pq_tq >> 4) & 0xf;
+ /*
+ * Only 8-bit Qk values for 8-bit sample precision. Extended
+ * sequential DCT with 12-bit sample precision also supports
+ * 16-bit Qk values.
+ */
+ if (pq != 0 && (pq != 1 || precision != 12))
+ return -EINVAL;
+
+ /* quantization table destination identifier */
+ tq = pq_tq & 0xf;
+ if (tq > 3)
+ return -EINVAL;
+
+ /* quantization table element */
+ qk = stream->curr;
+ ret = jpeg_skip(stream, pq ? 128 : 64);
+ if (ret < 0)
+ return -EINVAL;
+
+ if (tables) {
+ tables[tq].start = qk;
+ tables[tq].length = pq ? 128 : 64;
+ }
+
+ len -= pq ? 129 : 65;
+ }
+
+ return 0;
+}
+
+/* B.2.4.2 Huffman table-specification syntax */
+static int jpeg_parse_huffman_tables(struct jpeg_stream *stream,
+ struct v4l2_jpeg_reference *tables)
+{
+ int mt;
+ int len = jpeg_get_word_be(stream);
+
+ if (len < 0)
+ return len;
+ /* Table B.5 - Huffman table specification parameter sizes and values */
+ if (len < 2 + 17)
+ return -EINVAL;
+
+ for (len -= 2; len >= 17; len -= 17 + mt) {
+ u8 tc, th, *table;
+ int tc_th = jpeg_get_byte(stream);
+ int i, ret;
+
+ if (tc_th < 0)
+ return tc_th;
+
+ /* table class - 0 = DC, 1 = AC */
+ tc = (tc_th >> 4) & 0xf;
+ if (tc > 1)
+ return -EINVAL;
+
+ /* huffman table destination identifier */
+ th = tc_th & 0xf;
+ /* only two Huffman tables for baseline DCT */
+ if (th > 1)
+ return -EINVAL;
+
+ /* BITS - number of Huffman codes with length i */
+ table = stream->curr;
+ mt = 0;
+ for (i = 0; i < 16; i++) {
+ int li;
+
+ li = jpeg_get_byte(stream);
+ if (li < 0)
+ return li;
+
+ mt += li;
+ }
+ /* HUFFVAL - values associated with each Huffman code */
+ ret = jpeg_skip(stream, mt);
+ if (ret < 0)
+ return ret;
+
+ if (tables) {
+ tables[(tc << 1) | th].start = table;
+ tables[(tc << 1) | th].length = stream->curr - table;
+ }
+ }
+
+ return jpeg_skip(stream, len - 2);
+}
+
+/* B.2.4.4 Restart interval definition syntax */
+static int jpeg_parse_restart_interval(struct jpeg_stream *stream,
+ u16 *restart_interval)
+{
+ int len = jpeg_get_word_be(stream);
+ int ri;
+
+ if (len < 0)
+ return len;
+ if (len != 4)
+ return -EINVAL;
+
+ ri = jpeg_get_word_be(stream);
+ if (ri < 0)
+ return ri;
+
+ *restart_interval = ri;
+
+ return 0;
+}
+
+static int jpeg_skip_segment(struct jpeg_stream *stream)
+{
+ int len = jpeg_get_word_be(stream);
+
+ if (len < 0)
+ return len;
+ if (len < 2)
+ return -EINVAL;
+
+ return jpeg_skip(stream, len - 2);
+}
+
+/**
+ * jpeg_parse_header - locate marker segments and optionally parse headers
+ * @buf: address of the JPEG buffer, should start with a SOI marker
+ * @len: length of the JPEG buffer
+ * @out: returns marker segment positions and optionally parsed headers
+ *
+ * The out->scan_header pointer must be initialized to NULL or point to a valid
+ * v4l2_jpeg_scan_header structure. The out->huffman_tables and
+ * out->quantization_tables pointers must be initialized to NULL or point to a
+ * valid array of 4 v4l2_jpeg_reference structures each.
+ *
+ * Returns 0 or negative error if parsing failed.
+ */
+int v4l2_jpeg_parse_header(void *buf, size_t len, struct v4l2_jpeg_header *out)
+{
+ struct jpeg_stream stream;
+ int marker;
+ int ret = 0;
+
+ stream.curr = buf;
+ stream.end = stream.curr + len;
+
+ out->num_dht = 0;
+ out->num_dqt = 0;
+
+ /* the first marker must be SOI */
+ marker = jpeg_next_marker(&stream);
+ if (marker < 0)
+ return marker;
+ if (marker != SOI)
+ return -EINVAL;
+
+ /* loop through marker segments */
+ while ((marker = jpeg_next_marker(&stream)) >= 0) {
+ switch (marker) {
+ /* baseline DCT, extended sequential DCT */
+ case SOF0 ... SOF1:
+ ret = jpeg_reference_segment(&stream, &out->sof);
+ if (ret < 0)
+ return ret;
+ ret = jpeg_parse_frame_header(&stream, marker,
+ &out->frame);
+ break;
+ /* progressive, lossless */
+ case SOF2 ... SOF3:
+ /* differential coding */
+ case SOF5 ... SOF7:
+ /* arithmetic coding */
+ case SOF9 ... SOF11:
+ case SOF13 ... SOF15:
+ case DAC:
+ case TEM:
+ return -EINVAL;
+
+ case DHT:
+ ret = jpeg_reference_segment(&stream,
+ &out->dht[out->num_dht++ % 4]);
+ if (ret < 0)
+ return ret;
+ ret = jpeg_parse_huffman_tables(&stream,
+ out->huffman_tables);
+ break;
+ case DQT:
+ ret = jpeg_reference_segment(&stream,
+ &out->dqt[out->num_dqt++ % 4]);
+ if (ret < 0)
+ return ret;
+ ret = jpeg_parse_quantization_tables(&stream,
+ out->frame.precision,
+ out->quantization_tables);
+ break;
+ case DRI:
+ ret = jpeg_parse_restart_interval(&stream,
+ &out->restart_interval);
+ break;
+
+ case SOS:
+ ret = jpeg_reference_segment(&stream, &out->sos);
+ if (ret < 0)
+ return ret;
+ ret = jpeg_parse_scan_header(&stream, out->scan);
+ /*
+ * stop parsing, the scan header marks the beginning of
+ * the entropy coded segment
+ */
+ out->ecs_offset = stream.curr - (u8 *)buf;
+ return ret;
+
+ /* markers without parameters */
+ case RST0 ... RST7: /* restart */
+ case SOI: /* start of image */
+ case EOI: /* end of image */
+ break;
+
+ /* skip unknown or unsupported marker segments */
+ default:
+ ret = jpeg_skip_segment(&stream);
+ break;
+ }
+ if (ret < 0)
+ return ret;
+ }
+
+ return marker;
+}
+EXPORT_SYMBOL_GPL(v4l2_jpeg_parse_header);
+
+/**
+ * v4l2_jpeg_parse_frame_header - parse frame header
+ * @buf: address of the frame header, after the SOF0 marker
+ * @len: length of the frame header
+ * @frame_header: returns the parsed frame header
+ *
+ * Returns 0 or negative error if parsing failed.
+ */
+int v4l2_jpeg_parse_frame_header(void *buf, size_t len,
+ struct v4l2_jpeg_frame_header *frame_header)
+{
+ struct jpeg_stream stream;
+
+ stream.curr = buf;
+ stream.end = stream.curr + len;
+ return jpeg_parse_frame_header(&stream, SOF0, frame_header);
+}
+EXPORT_SYMBOL_GPL(v4l2_jpeg_parse_frame_header);
+
+/**
+ * v4l2_jpeg_parse_scan_header - parse scan header
+ * @buf: address of the scan header, after the SOS marker
+ * @len: length of the scan header
+ * @scan_header: returns the parsed scan header
+ *
+ * Returns 0 or negative error if parsing failed.
+ */
+int v4l2_jpeg_parse_scan_header(void *buf, size_t len,
+ struct v4l2_jpeg_scan_header *scan_header)
+{
+ struct jpeg_stream stream;
+
+ stream.curr = buf;
+ stream.end = stream.curr + len;
+ return jpeg_parse_scan_header(&stream, scan_header);
+}
+EXPORT_SYMBOL_GPL(v4l2_jpeg_parse_scan_header);
+
+/**
+ * v4l2_jpeg_parse_quantization_tables - parse quantization tables segment
+ * @buf: address of the quantization table segment, after the DQT marker
+ * @len: length of the quantization table segment
+ * @precision: sample precision (P) in bits per component
+ * @q_tables: returns four references into the buffer for the
+ * four possible quantization table destinations
+ *
+ * Returns 0 or negative error if parsing failed.
+ */
+int v4l2_jpeg_parse_quantization_tables(void *buf, size_t len, u8 precision,
+ struct v4l2_jpeg_reference *q_tables)
+{
+ struct jpeg_stream stream;
+
+ stream.curr = buf;
+ stream.end = stream.curr + len;
+ return jpeg_parse_quantization_tables(&stream, precision, q_tables);
+}
+EXPORT_SYMBOL_GPL(v4l2_jpeg_parse_quantization_tables);
+
+/**
+ * v4l2_jpeg_parse_huffman_tables - parse huffman tables segment
+ * @buf: address of the Huffman table segment, after the DHT marker
+ * @len: length of the Huffman table segment
+ * @huffman_tables: returns four references into the buffer for the
+ * four possible Huffman table destinations, in
+ * the order DC0, DC1, AC0, AC1
+ *
+ * Returns 0 or negative error if parsing failed.
+ */
+int v4l2_jpeg_parse_huffman_tables(void *buf, size_t len,
+ struct v4l2_jpeg_reference *huffman_tables)
+{
+ struct jpeg_stream stream;
+
+ stream.curr = buf;
+ stream.end = stream.curr + len;
+ return jpeg_parse_huffman_tables(&stream, huffman_tables);
+}
+EXPORT_SYMBOL_GPL(v4l2_jpeg_parse_huffman_tables);
--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * V4L2 JPEG helpers header
+ *
+ * Copyright (C) 2019 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
+ *
+ * For reference, see JPEG ITU-T.81 (ISO/IEC 10918-1)
+ */
+
+#ifndef _V4L2_JPEG_H
+#define _V4L2_JPEG_H
+
+#include <linux/v4l2-controls.h>
+
+#define V4L2_JPEG_MAX_COMPONENTS 4
+#define V4L2_JPEG_MAX_TABLES 4
+
+/**
+ * struct v4l2_jpeg_reference - reference into the JPEG buffer
+ * @start: pointer to the start of the referenced segment or table
+ * @length: size of the referenced segment or table
+ *
+ * Wnen referencing marker segments, start points right after the marker code,
+ * and length is the size of the segment parameters, excluding the marker code.
+ */
+struct v4l2_jpeg_reference {
+ u8 *start;
+ size_t length;
+};
+
+/* B.2.2 Frame header syntax */
+
+/**
+ * struct v4l2_jpeg_frame_component_spec - frame component-specification
+ * @component_identifier: C[i]
+ * @horizontal_sampling_factor: H[i]
+ * @vertical_sampling_factor: V[i]
+ * @quantization_table_selector: quantization table destination selector Tq[i]
+ */
+struct v4l2_jpeg_frame_component_spec {
+ u8 component_identifier;
+ u8 horizontal_sampling_factor;
+ u8 vertical_sampling_factor;
+ u8 quantization_table_selector;
+};
+
+/**
+ * struct v4l2_jpeg_frame_header - JPEG frame header
+ * @height: Y
+ * @width: X
+ * @precision: P
+ * @num_components: Nf
+ * @component: component-specification, see v4l2_jpeg_frame_component_spec
+ * @subsampling: decoded subsampling from component-specification
+ */
+struct v4l2_jpeg_frame_header {
+ u16 height;
+ u16 width;
+ u8 precision;
+ u8 num_components;
+ struct v4l2_jpeg_frame_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
+ enum v4l2_jpeg_chroma_subsampling subsampling;
+};
+
+/* B.2.3 Scan header syntax */
+
+/**
+ * struct v4l2_jpeg_scan_component_spec - scan component-specification
+ * @component_selector: Cs[j]
+ * @dc_entropy_coding_table_selector: Td[j]
+ * @ac_entropy_coding_table_selector: Ta[j]
+ */
+struct v4l2_jpeg_scan_component_spec {
+ u8 component_selector;
+ u8 dc_entropy_coding_table_selector;
+ u8 ac_entropy_coding_table_selector;
+};
+
+/**
+ * struct v4l2_jpeg_scan_header - JPEG scan header
+ * @num_components: Ns
+ * @component: component-specification, see v4l2_jpeg_scan_component_spec
+ */
+struct v4l2_jpeg_scan_header {
+ u8 num_components; /* Ns */
+ struct v4l2_jpeg_scan_component_spec component[V4L2_JPEG_MAX_COMPONENTS];
+ /* Ss, Se, Ah, and Al are not used by any driver */
+};
+
+/**
+ * struct v4l2_jpeg_header - parsed JPEG header
+ * @sof: pointer to frame header and size
+ * @sos: pointer to scan header and size
+ * @dht: pointers to huffman tables and sizes
+ * @dqt: pointers to quantization tables and sizes
+ * @frame: parsed frame header
+ * @scan: pointer to parsed scan header, optional
+ * @quantization_tables: references to four quantization tables, optional
+ * @huffman_tables: references to four Huffman tables in DC0, DC1, AC0, AC1
+ * order, optional
+ * @restart_interval: number of MCU per restart interval, Ri
+ * @ecs_offset: buffer offset in bytes to the entropy coded segment
+ *
+ * When this structure is passed to v4l2_jpeg_parse_header, the optional scan,
+ * quantization_tables, and huffman_tables pointers must be initialized to NULL
+ * or point at valid memory.
+ */
+struct v4l2_jpeg_header {
+ struct v4l2_jpeg_reference sof;
+ struct v4l2_jpeg_reference sos;
+ unsigned int num_dht;
+ struct v4l2_jpeg_reference dht[V4L2_JPEG_MAX_TABLES];
+ unsigned int num_dqt;
+ struct v4l2_jpeg_reference dqt[V4L2_JPEG_MAX_TABLES];
+
+ struct v4l2_jpeg_frame_header frame;
+ struct v4l2_jpeg_scan_header *scan;
+ struct v4l2_jpeg_reference *quantization_tables;
+ struct v4l2_jpeg_reference *huffman_tables;
+ u16 restart_interval;
+ size_t ecs_offset;
+};
+
+int v4l2_jpeg_parse_header(void *buf, size_t len, struct v4l2_jpeg_header *out);
+
+int v4l2_jpeg_parse_frame_header(void *buf, size_t len,
+ struct v4l2_jpeg_frame_header *frame_header);
+int v4l2_jpeg_parse_scan_header(void *buf, size_t len,
+ struct v4l2_jpeg_scan_header *scan_header);
+int v4l2_jpeg_parse_quantization_tables(void *buf, size_t len, u8 precision,
+ struct v4l2_jpeg_reference *q_tables);
+int v4l2_jpeg_parse_huffman_tables(void *buf, size_t len,
+ struct v4l2_jpeg_reference *huffman_tables);
+
+#endif
projects / platform / kernel / linux-rpi.git / commitdiff