media: imx-jpeg: Add V4L2 driver for i.MX8 JPEG Encoder/Decoder

V4L2 driver for the JPEG encoder/decoder from i.MX8QXP/i.MX8QM application
processors.
The multi-planar buffers API is used.

Baseline and extended sequential jpeg decoding is supported.
Progressive jpeg decoding is not supported by the IP.
Supports encode and decode of various formats:
     YUV444, YUV422, YUV420, RGB, ARGB, Gray
YUV420 is the only multi-planar format supported.
Minimum resolution is 64 x 64, maximum 8192 x 8192.
The alignment requirements for the resolution depend on the format,
multiple of 16 resolutions should work for all formats.

v4l2-compliance tests are passing, including the
streaming tests, "v4l2-compliance -s"

[hverkuil: fix kernel-doc typos]
Signed-off-by: Mirela Rabulea <mirela.rabulea@nxp.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/Kconfig

@@ -253,6 +253,8 @@ config VIDEO_IMX_PXP
 	  The i.MX Pixel Pipeline is a memory-to-memory engine for scaling,
 	  color space conversion, and rotation.
 
+source "drivers/media/platform/imx-jpeg/Kconfig"
+
 config VIDEO_MEDIATEK_JPEG
 	tristate "Mediatek JPEG Codec driver"
 	depends on MTK_IOMMU_V1 || MTK_IOMMU || COMPILE_TEST

drivers/media/platform/Makefile

@@ -21,6 +21,7 @@ obj-$(CONFIG_VIDEO_MX2_EMMAPRP)		+= mx2_emmaprp.o
 obj-$(CONFIG_VIDEO_CODA)		+= coda/
 
 obj-$(CONFIG_VIDEO_IMX_PXP)		+= imx-pxp.o
+obj-$(CONFIG_VIDEO_IMX8_JPEG)		+= imx-jpeg/
 
 obj-$(CONFIG_VIDEO_MEM2MEM_DEINTERLACE)	+= m2m-deinterlace.o
 

drivers/media/platform/imx-jpeg/Kconfig

+# SPDX-License-Identifier: GPL-2.0
+config VIDEO_IMX8_JPEG
+	tristate "IMX8 JPEG Encoder/Decoder"
+	depends on VIDEO_DEV && VIDEO_V4L2
+	select VIDEOBUF2_DMA_CONTIG
+	select V4L2_MEM2MEM_DEV
+	select V4L2_JPEG_HELPER
+	default m
+	help
+	  This is a video4linux2 driver for the i.MX8 QXP/QM integrated
+	  JPEG encoder/decoder.

drivers/media/platform/imx-jpeg/Makefile

+# SPDX-License-Identifier: GPL-2.0
+mxc-jpeg-encdec-objs := mxc-jpeg-hw.o mxc-jpeg.o
+obj-$(CONFIG_VIDEO_IMX8_JPEG) += mxc-jpeg-encdec.o

drivers/media/platform/imx-jpeg/mxc-jpeg-hw.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * i.MX8QXP/i.MX8QM JPEG encoder/decoder v4l2 driver
+ *
+ * Copyright 2018-2019 NXP
+ */
+
+#include <linux/delay.h>
+#include <media/videobuf2-core.h>
+#include "mxc-jpeg-hw.h"
+
+#define print_wrapper_reg(dev, base_address, reg_offset)\
+		internal_print_wrapper_reg(dev, (base_address), #reg_offset,\
+					   (reg_offset))
+#define internal_print_wrapper_reg(dev, base_address, reg_name, reg_offset) {\
+		int val;\
+		val = readl((base_address) + (reg_offset));\
+		dev_dbg(dev, "Wrapper reg %s = 0x%x\n", reg_name, val);\
+}
+
+void print_descriptor_info(struct device *dev, struct mxc_jpeg_desc *desc)
+{
+	dev_dbg(dev, " MXC JPEG NEXT_DESCPT_PTR 0x%x\n",
+		desc->next_descpt_ptr);
+	dev_dbg(dev, " MXC JPEG BUF_BASE0 0x%x\n", desc->buf_base0);
+	dev_dbg(dev, " MXC JPEG BUF_BASE1 0x%x\n", desc->buf_base1);
+	dev_dbg(dev, " MXC JPEG LINE_PITCH %d\n", desc->line_pitch);
+	dev_dbg(dev, " MXC JPEG STM_BUFBASE 0x%x\n", desc->stm_bufbase);
+	dev_dbg(dev, " MXC JPEG STM_BUFSIZE %d\n", desc->stm_bufsize);
+	dev_dbg(dev, " MXC JPEG IMGSIZE %x (%d x %d)\n", desc->imgsize,
+		desc->imgsize >> 16, desc->imgsize & 0xFFFF);
+	dev_dbg(dev, " MXC JPEG STM_CTRL 0x%x\n", desc->stm_ctrl);
+}
+
+void print_cast_status(struct device *dev, void __iomem *reg,
+		       unsigned int mode)
+{
+	dev_dbg(dev, "CAST IP status regs:\n");
+	print_wrapper_reg(dev, reg, CAST_STATUS0);
+	print_wrapper_reg(dev, reg, CAST_STATUS1);
+	print_wrapper_reg(dev, reg, CAST_STATUS2);
+	print_wrapper_reg(dev, reg, CAST_STATUS3);
+	print_wrapper_reg(dev, reg, CAST_STATUS4);
+	print_wrapper_reg(dev, reg, CAST_STATUS5);
+	print_wrapper_reg(dev, reg, CAST_STATUS6);
+	print_wrapper_reg(dev, reg, CAST_STATUS7);
+	print_wrapper_reg(dev, reg, CAST_STATUS8);
+	print_wrapper_reg(dev, reg, CAST_STATUS9);
+	print_wrapper_reg(dev, reg, CAST_STATUS10);
+	print_wrapper_reg(dev, reg, CAST_STATUS11);
+	print_wrapper_reg(dev, reg, CAST_STATUS12);
+	print_wrapper_reg(dev, reg, CAST_STATUS13);
+	if (mode == MXC_JPEG_DECODE)
+		return;
+	print_wrapper_reg(dev, reg, CAST_STATUS14);
+	print_wrapper_reg(dev, reg, CAST_STATUS15);
+	print_wrapper_reg(dev, reg, CAST_STATUS16);
+	print_wrapper_reg(dev, reg, CAST_STATUS17);
+	print_wrapper_reg(dev, reg, CAST_STATUS18);
+	print_wrapper_reg(dev, reg, CAST_STATUS19);
+}
+
+void print_wrapper_info(struct device *dev, void __iomem *reg)
+{
+	dev_dbg(dev, "Wrapper regs:\n");
+	print_wrapper_reg(dev, reg, GLB_CTRL);
+	print_wrapper_reg(dev, reg, COM_STATUS);
+	print_wrapper_reg(dev, reg, BUF_BASE0);
+	print_wrapper_reg(dev, reg, BUF_BASE1);
+	print_wrapper_reg(dev, reg, LINE_PITCH);
+	print_wrapper_reg(dev, reg, STM_BUFBASE);
+	print_wrapper_reg(dev, reg, STM_BUFSIZE);
+	print_wrapper_reg(dev, reg, IMGSIZE);
+	print_wrapper_reg(dev, reg, STM_CTRL);
+}
+
+void mxc_jpeg_enable_irq(void __iomem *reg, int slot)
+{
+	writel(0xFFFFFFFF, reg + MXC_SLOT_OFFSET(slot, SLOT_IRQ_EN));
+}
+
+void mxc_jpeg_sw_reset(void __iomem *reg)
+{
+	/*
+	 * engine soft reset, internal state machine reset
+	 * this will not reset registers, however, it seems
+	 * the registers may remain inconsistent with the internal state
+	 * so, on purpose, at least let GLB_CTRL bits clear after this reset
+	 */
+	writel(GLB_CTRL_SFT_RST, reg + GLB_CTRL);
+}
+
+void mxc_jpeg_enc_mode_conf(struct device *dev, void __iomem *reg)
+{
+	dev_dbg(dev, "CAST Encoder CONFIG...\n");
+	/*
+	 * "Config_Mode" enabled, "Config_Mode auto clear enabled",
+	 */
+	writel(0xa0, reg + CAST_MODE);
+
+	/* all markers and segments */
+	writel(0x3ff, reg + CAST_CFG_MODE);
+
+	/* quality factor */
+	writel(0x4b, reg + CAST_QUALITY);
+}
+
+void mxc_jpeg_enc_mode_go(struct device *dev, void __iomem *reg)
+{
+	dev_dbg(dev, "CAST Encoder GO...\n");
+	/*
+	 * "GO" enabled, "GO bit auto clear" enabled
+	 */
+	writel(0x140, reg + CAST_MODE);
+}
+
+void mxc_jpeg_dec_mode_go(struct device *dev, void __iomem *reg)
+{
+	dev_dbg(dev, "CAST Decoder GO...\n");
+	writel(MXC_DEC_EXIT_IDLE_MODE, reg + CAST_CTRL);
+}
+
+int mxc_jpeg_enable(void __iomem *reg)
+{
+	u32 regval;
+
+	writel(GLB_CTRL_JPG_EN, reg + GLB_CTRL);
+	regval = readl(reg);
+	return regval;
+}
+
+void mxc_jpeg_enable_slot(void __iomem *reg, int slot)
+{
+	u32 regval;
+
+	regval = readl(reg + GLB_CTRL);
+	writel(GLB_CTRL_SLOT_EN(slot) | regval, reg + GLB_CTRL);
+}
+
+void mxc_jpeg_set_l_endian(void __iomem *reg, int le)
+{
+	u32 regval;
+
+	regval = readl(reg + GLB_CTRL);
+	regval &= ~GLB_CTRL_L_ENDIAN(1); /* clear */
+	writel(GLB_CTRL_L_ENDIAN(le) | regval, reg + GLB_CTRL); /* set */
+}
+
+void mxc_jpeg_set_bufsize(struct mxc_jpeg_desc *desc,  u32 bufsize)
+{
+	desc->stm_bufsize = bufsize;
+}
+
+void mxc_jpeg_set_res(struct mxc_jpeg_desc *desc, u16 w, u16 h)
+{
+	desc->imgsize = w << 16 | h;
+}
+
+void mxc_jpeg_set_line_pitch(struct mxc_jpeg_desc *desc, u32 line_pitch)
+{
+	desc->line_pitch = line_pitch;
+}
+
+void mxc_jpeg_set_desc(u32 desc, void __iomem *reg, int slot)
+{
+	writel(desc | MXC_NXT_DESCPT_EN,
+	       reg + MXC_SLOT_OFFSET(slot, SLOT_NXT_DESCPT_PTR));
+}

drivers/media/platform/imx-jpeg/mxc-jpeg-hw.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * i.MX8QXP/i.MX8QM JPEG encoder/decoder v4l2 driver
+ *
+ * Copyright 2018-2019 NXP
+ */
+
+#ifndef _MXC_JPEG_HW_H
+#define _MXC_JPEG_HW_H
+
+/* JPEG Decoder/Encoder Wrapper Register Map */
+#define GLB_CTRL			0x0
+#define COM_STATUS			0x4
+#define BUF_BASE0			0x14
+#define BUF_BASE1			0x18
+#define LINE_PITCH			0x1C
+#define STM_BUFBASE			0x20
+#define STM_BUFSIZE			0x24
+#define IMGSIZE				0x28
+#define STM_CTRL			0x2C
+
+/* CAST JPEG-Decoder/Encoder Status Register Map (read-only)*/
+#define CAST_STATUS0			0x100
+#define CAST_STATUS1			0x104
+#define CAST_STATUS2			0x108
+#define CAST_STATUS3			0x10c
+#define CAST_STATUS4			0x110
+#define CAST_STATUS5			0x114
+#define CAST_STATUS6			0x118
+#define CAST_STATUS7			0x11c
+#define CAST_STATUS8			0x120
+#define CAST_STATUS9			0x124
+#define CAST_STATUS10			0x128
+#define CAST_STATUS11			0x12c
+#define CAST_STATUS12			0x130
+#define CAST_STATUS13			0x134
+/* the following are for encoder only */
+#define CAST_STATUS14		0x138
+#define CAST_STATUS15		0x13c
+#define CAST_STATUS16		0x140
+#define CAST_STATUS17		0x144
+#define CAST_STATUS18		0x148
+#define CAST_STATUS19		0x14c
+
+/* CAST JPEG-Decoder Control Register Map (write-only) */
+#define CAST_CTRL			CAST_STATUS13
+
+/* CAST JPEG-Encoder Control Register Map (write-only) */
+#define CAST_MODE			CAST_STATUS0
+#define CAST_CFG_MODE			CAST_STATUS1
+#define CAST_QUALITY			CAST_STATUS2
+#define CAST_RSVD			CAST_STATUS3
+#define CAST_REC_REGS_SEL		CAST_STATUS4
+#define CAST_LUMTH			CAST_STATUS5
+#define CAST_CHRTH			CAST_STATUS6
+#define CAST_NOMFRSIZE_LO		CAST_STATUS7
+#define CAST_NOMFRSIZE_HI		CAST_STATUS8
+#define CAST_OFBSIZE_LO			CAST_STATUS9
+#define CAST_OFBSIZE_HI			CAST_STATUS10
+
+#define MXC_MAX_SLOTS	1 /* TODO use all 4 slots*/
+/* JPEG-Decoder Wrapper Slot Registers 0..3 */
+#define SLOT_BASE			0x10000
+#define SLOT_STATUS			0x0
+#define SLOT_IRQ_EN			0x4
+#define SLOT_BUF_PTR			0x8
+#define SLOT_CUR_DESCPT_PTR		0xC
+#define SLOT_NXT_DESCPT_PTR		0x10
+#define MXC_SLOT_OFFSET(slot, offset)	((SLOT_BASE * ((slot) + 1)) + (offset))
+
+/* GLB_CTRL fields */
+#define GLB_CTRL_JPG_EN					0x1
+#define GLB_CTRL_SFT_RST				(0x1 << 1)
+#define GLB_CTRL_DEC_GO					(0x1 << 2)
+#define GLB_CTRL_L_ENDIAN(le)				((le) << 3)
+#define GLB_CTRL_SLOT_EN(slot)				(0x1 << ((slot) + 4))
+
+/* COM_STAUS fields */
+#define COM_STATUS_DEC_ONGOING(r)		(((r) & (1 << 31)) >> 31)
+#define COM_STATUS_CUR_SLOT(r)			(((r) & (0x3 << 29)) >> 29)
+
+/* STM_CTRL fields */
+#define STM_CTRL_PIXEL_PRECISION		(0x1 << 2)
+#define STM_CTRL_IMAGE_FORMAT(img_fmt)		((img_fmt) << 3)
+#define STM_CTRL_IMAGE_FORMAT_MASK		(0xF << 3)
+#define STM_CTRL_BITBUF_PTR_CLR(clr)		((clr) << 7)
+#define STM_CTRL_AUTO_START(go)			((go) << 8)
+#define STM_CTRL_CONFIG_MOD(mod)		((mod) << 9)
+
+/* SLOT_STATUS fields for slots 0..3 */
+#define SLOT_STATUS_FRMDONE			(0x1 << 3)
+#define SLOT_STATUS_ENC_CONFIG_ERR		(0x1 << 8)
+
+/* SLOT_IRQ_EN fields TBD */
+
+#define MXC_NXT_DESCPT_EN			0x1
+#define MXC_DEC_EXIT_IDLE_MODE			0x4
+
+/* JPEG-Decoder Wrapper - STM_CTRL Register Fields */
+#define MXC_PIXEL_PRECISION(precision) ((precision) / 8 << 2)
+enum mxc_jpeg_image_format {
+	MXC_JPEG_INVALID = -1,
+	MXC_JPEG_YUV420 = 0x0, /* 2 Plannar, Y=1st plane UV=2nd plane */
+	MXC_JPEG_YUV422 = 0x1, /* 1 Plannar, YUYV sequence */
+	MXC_JPEG_RGB	= 0x2, /* RGBRGB packed format */
+	MXC_JPEG_YUV444	= 0x3, /* 1 Plannar, YUVYUV sequence */
+	MXC_JPEG_GRAY = 0x4, /* Y8 or Y12 or Single Component */
+	MXC_JPEG_RESERVED = 0x5,
+	MXC_JPEG_ARGB	= 0x6,
+};
+
+#include "mxc-jpeg.h"
+void print_descriptor_info(struct device *dev, struct mxc_jpeg_desc *desc);
+void print_cast_status(struct device *dev, void __iomem *reg,
+		       unsigned int mode);
+void print_wrapper_info(struct device *dev, void __iomem *reg);
+void mxc_jpeg_sw_reset(void __iomem *reg);
+int mxc_jpeg_enable(void __iomem *reg);
+void wait_frmdone(struct device *dev, void __iomem *reg);
+void mxc_jpeg_enc_mode_conf(struct device *dev, void __iomem *reg);
+void mxc_jpeg_enc_mode_go(struct device *dev, void __iomem *reg);
+void mxc_jpeg_dec_mode_go(struct device *dev, void __iomem *reg);
+int mxc_jpeg_get_slot(void __iomem *reg);
+u32 mxc_jpeg_get_offset(void __iomem *reg, int slot);
+void mxc_jpeg_enable_slot(void __iomem *reg, int slot);
+void mxc_jpeg_set_l_endian(void __iomem *reg, int le);
+void mxc_jpeg_enable_irq(void __iomem *reg, int slot);
+int mxc_jpeg_set_input(void __iomem *reg, u32 in_buf, u32 bufsize);
+int mxc_jpeg_set_output(void __iomem *reg, u16 out_pitch, u32 out_buf,
+			u16 w, u16 h);
+void mxc_jpeg_set_config_mode(void __iomem *reg, int config_mode);
+int mxc_jpeg_set_params(struct mxc_jpeg_desc *desc,  u32 bufsize, u16
+			out_pitch, u32 format);
+void mxc_jpeg_set_bufsize(struct mxc_jpeg_desc *desc,  u32 bufsize);
+void mxc_jpeg_set_res(struct mxc_jpeg_desc *desc, u16 w, u16 h);
+void mxc_jpeg_set_line_pitch(struct mxc_jpeg_desc *desc, u32 line_pitch);
+void mxc_jpeg_set_desc(u32 desc, void __iomem *reg, int slot);
+void mxc_jpeg_set_regs_from_desc(struct mxc_jpeg_desc *desc,
+				 void __iomem *reg);
+#endif

drivers/media/platform/imx-jpeg/mxc-jpeg.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * i.MX8QXP/i.MX8QM JPEG encoder/decoder v4l2 driver
+ *
+ * Copyright 2018-2019 NXP
+ */
+
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-fh.h>
+
+#ifndef _MXC_JPEG_CORE_H
+#define _MXC_JPEG_CORE_H
+
+#define MXC_JPEG_NAME			"mxc-jpeg"
+#define MXC_JPEG_FMT_TYPE_ENC		0
+#define MXC_JPEG_FMT_TYPE_RAW		1
+#define MXC_JPEG_DEFAULT_WIDTH		1280
+#define MXC_JPEG_DEFAULT_HEIGHT		720
+#define MXC_JPEG_DEFAULT_PFMT		V4L2_PIX_FMT_RGB24
+#define MXC_JPEG_MIN_WIDTH		64
+#define MXC_JPEG_MIN_HEIGHT		64
+#define MXC_JPEG_MAX_WIDTH		0x2000
+#define MXC_JPEG_MAX_HEIGHT		0x2000
+#define MXC_JPEG_MAX_CFG_STREAM		0x1000
+#define MXC_JPEG_H_ALIGN		3
+#define MXC_JPEG_W_ALIGN		3
+#define MXC_JPEG_MAX_SIZEIMAGE		0xFFFFFC00
+#define MXC_JPEG_MAX_PLANES		2
+
+enum mxc_jpeg_enc_state {
+	MXC_JPEG_ENCODING	= 0, /* jpeg encode phase */
+	MXC_JPEG_ENC_CONF	= 1, /* jpeg encoder config phase */
+};
+
+enum mxc_jpeg_mode {
+	MXC_JPEG_DECODE	= 0, /* jpeg decode mode */
+	MXC_JPEG_ENCODE	= 1, /* jpeg encode mode */
+};
+
+/**
+ * struct mxc_jpeg_fmt - driver's internal color format data
+ * @name:	format description
+ * @fourcc:	fourcc code, 0 if not applicable
+ * @subsampling: subsampling of jpeg components
+ * @nc:		number of color components
+ * @depth:	number of bits per pixel
+ * @colplanes:	number of color planes (1 for packed formats)
+ * @h_align:	horizontal alignment order (align to 2^h_align)
+ * @v_align:	vertical alignment order (align to 2^v_align)
+ * @flags:	flags describing format applicability
+ */
+struct mxc_jpeg_fmt {
+	char					*name;
+	u32					fourcc;
+	enum v4l2_jpeg_chroma_subsampling	subsampling;
+	int					nc;
+	int					depth;
+	int					colplanes;
+	int					h_align;
+	int					v_align;
+	u32					flags;
+};
+
+struct mxc_jpeg_desc {
+	u32 next_descpt_ptr;
+	u32 buf_base0;
+	u32 buf_base1;
+	u32 line_pitch;
+	u32 stm_bufbase;
+	u32 stm_bufsize;
+	u32 imgsize;
+	u32 stm_ctrl;
+} __packed;
+
+struct mxc_jpeg_q_data {
+	struct mxc_jpeg_fmt	*fmt;
+	u32			sizeimage[MXC_JPEG_MAX_PLANES];
+	u32			bytesperline[MXC_JPEG_MAX_PLANES];
+	int			w;
+	int			w_adjusted;
+	int			h;
+	int			h_adjusted;
+	unsigned int		sequence;
+};
+
+struct mxc_jpeg_ctx {
+	struct mxc_jpeg_dev		*mxc_jpeg;
+	struct mxc_jpeg_q_data		out_q;
+	struct mxc_jpeg_q_data		cap_q;
+	struct v4l2_fh			fh;
+	enum mxc_jpeg_enc_state		enc_state;
+	unsigned int			stopping;
+	unsigned int			slot;
+};
+
+struct mxc_jpeg_slot_data {
+	bool used;
+	struct mxc_jpeg_desc *desc; // enc/dec descriptor
+	struct mxc_jpeg_desc *cfg_desc; // configuration descriptor
+	void *cfg_stream_vaddr; // configuration bitstream virtual address
+	unsigned int cfg_stream_size;
+	dma_addr_t desc_handle;
+	dma_addr_t cfg_desc_handle; // configuration descriptor dma address
+	dma_addr_t cfg_stream_handle; // configuration bitstream dma address
+};
+
+struct mxc_jpeg_dev {
+	spinlock_t			hw_lock; /* hardware access lock */
+	unsigned int			mode;
+	struct mutex			lock; /* v4l2 ioctls serialization */
+	struct platform_device		*pdev;
+	struct device			*dev;
+	void __iomem			*base_reg;
+	struct v4l2_device		v4l2_dev;
+	struct v4l2_m2m_dev		*m2m_dev;
+	struct video_device		*dec_vdev;
+	struct mxc_jpeg_slot_data	slot_data[MXC_MAX_SLOTS];
+	int				num_domains;
+	struct device			**pd_dev;
+	struct device_link		**pd_link;
+};
+
+/**
+ * struct mxc_jpeg_sof_comp - JPEG Start Of Frame component fields
+ * @id:				component id
+ * @v:				vertical sampling
+ * @h:				horizontal sampling
+ * @quantization_table_no:	id of quantization table
+ */
+struct mxc_jpeg_sof_comp {
+	u8 id;
+	u8 v :4;
+	u8 h :4;
+	u8 quantization_table_no;
+} __packed;
+
+#define MXC_JPEG_MAX_COMPONENTS 4
+/**
+ * struct mxc_jpeg_sof - JPEG Start Of Frame marker fields
+ * @length:		Start of Frame length
+ * @precision:		precision (bits per pixel per color component)
+ * @height:		image height
+ * @width:		image width
+ * @components_no:	number of color components
+ * @comp:		component fields for each color component
+ */
+struct mxc_jpeg_sof {
+	u16 length;
+	u8 precision;
+	u16 height, width;
+	u8 components_no;
+	struct mxc_jpeg_sof_comp comp[MXC_JPEG_MAX_COMPONENTS];
+} __packed;
+
+/**
+ * struct mxc_jpeg_sos_comp - JPEG Start Of Scan component fields
+ * @id:			component id
+ * @huffman_table_no:	id of the Huffman table
+ */
+struct mxc_jpeg_sos_comp {
+	u8 id; /*component id*/
+	u8 huffman_table_no;
+} __packed;
+
+/**
+ * struct mxc_jpeg_sos - JPEG Start Of Scan marker fields
+ * @length:		Start of Frame length
+ * @components_no:	number of color components
+ * @comp:		SOS component fields for each color component
+ * @ignorable_bytes:	ignorable bytes
+ */
+struct mxc_jpeg_sos {
+	u16 length;
+	u8 components_no;
+	struct mxc_jpeg_sos_comp comp[MXC_JPEG_MAX_COMPONENTS];
+	u8 ignorable_bytes[3];
+} __packed;
+
+#endif