diff --git a/MAINTAINERS b/MAINTAINERS
index 17ad1d7b5510..6ccb298cd8a4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -666,6 +666,12 @@ S:	Maintained
 F:	Documentation/i2c/busses/i2c-ali1563
 F:	drivers/i2c/busses/i2c-ali1563.c
 
+ALLEGRO DVT VIDEO IP CORE DRIVER
+M:	Michael Tretter <m.tretter@pengutronix.de>
+L:	linux-media@vger.kernel.org
+S:	Maintained
+F:	drivers/staging/media/allegro-dvt/
+
 ALLWINNER SECURITY SYSTEM
 M:	Corentin Labbe <clabbe.montjoie@gmail.com>
 L:	linux-crypto@vger.kernel.org
diff --git a/drivers/staging/media/Kconfig b/drivers/staging/media/Kconfig
index 19cadd17e542..0756c8669314 100644
--- a/drivers/staging/media/Kconfig
+++ b/drivers/staging/media/Kconfig
@@ -19,6 +19,8 @@ menuconfig STAGING_MEDIA
 if STAGING_MEDIA && MEDIA_SUPPORT
 
 # Please keep them in alphabetic order
+source "drivers/staging/media/allegro-dvt/Kconfig"
+
 source "drivers/staging/media/bcm2048/Kconfig"
 
 source "drivers/staging/media/davinci_vpfe/Kconfig"
diff --git a/drivers/staging/media/Makefile b/drivers/staging/media/Makefile
index edde1960b030..6578dfcbccb6 100644
--- a/drivers/staging/media/Makefile
+++ b/drivers/staging/media/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_VIDEO_ALLEGRO_DVT)	+= allegro-dvt/
 obj-$(CONFIG_I2C_BCM2048)	+= bcm2048/
 obj-$(CONFIG_VIDEO_IMX_MEDIA)	+= imx/
 obj-$(CONFIG_SOC_CAMERA_IMX074)	+= imx074/
diff --git a/drivers/staging/media/allegro-dvt/Kconfig b/drivers/staging/media/allegro-dvt/Kconfig
new file mode 100644
index 000000000000..96921e506c5f
--- /dev/null
+++ b/drivers/staging/media/allegro-dvt/Kconfig
@@ -0,0 +1,16 @@
+config VIDEO_ALLEGRO_DVT
+	tristate "Allegro DVT Video IP Cores"
+	depends on V4L_MEM2MEM_DRIVERS
+	depends on ARCH_ZYNQMP || COMPILE_TEST
+	depends on VIDEO_DEV && VIDEO_V4L2
+	select REGMAP
+	select REGMAP_MMIO
+	select V4L2_MEM2MEM_DEV
+	default n
+	help
+	  Support for the encoder and decoder video IP cores by Allegro DVT.
+	  These cores are found for example on the Xilinx ZynqMP SoC in the EV
+	  family and are called VCU in the reference manual.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called allegro.
diff --git a/drivers/staging/media/allegro-dvt/Makefile b/drivers/staging/media/allegro-dvt/Makefile
new file mode 100644
index 000000000000..bc30addee47f
--- /dev/null
+++ b/drivers/staging/media/allegro-dvt/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+allegro-objs := allegro-core.o
+
+obj-$(CONFIG_VIDEO_ALLEGRO_DVT) += allegro.o
diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
new file mode 100644
index 000000000000..db48747b345c
--- /dev/null
+++ b/drivers/staging/media/allegro-dvt/allegro-core.c
@@ -0,0 +1,2648 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Pengutronix, Michael Tretter <kernel@pengutronix.de>
+ *
+ * Allegro DVT encoder and decoder driver
+ */
+
+#include <linux/firmware.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/videodev2.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-mem2mem.h>
+#include <media/videobuf2-dma-contig.h>
+#include <media/videobuf2-v4l2.h>
+
+/*
+ * PG252 June 6, 2018 (H.264/H.265 Video Codec Unit v1.1) Chapter 3
+ *
+ * Configurable resolution
+ * - picture width and height multiple of 8
+ * - minimum size: 128 × 64
+ * - maximum width or height: 16384
+ * - maximum size: 33.5 megapixel
+ *
+ * I cannot trust the 33.5 megapixel, yet, and I do not understand the memory
+ * requirements at higher resolutions. Therefore, I limit the resolution to
+ * full HD, for now.
+ */
+#define ALLEGRO_WIDTH_MIN 128
+#define ALLEGRO_WIDTH_DEFAULT 1920
+#define ALLEGRO_WIDTH_MAX 1920
+#define ALLEGRO_HEIGHT_MIN 64
+#define ALLEGRO_HEIGHT_DEFAULT 1080
+#define ALLEGRO_HEIGHT_MAX 1080
+
+#define ALLEGRO_GOP_SIZE_DEFAULT 25
+#define ALLEGRO_GOP_SIZE_MAX 1000
+
+/*
+ * TODO The mailbox addresses and size are only valid for the 2018.2 release
+ * of the firmware. Firmware release 2018.3 uses double the size and changes
+ * the base addresses accordingly.
+ */
+#define MAILBOX_CMD                     0x7800
+#define MAILBOX_STATUS                  0x7c00
+#define MAILBOX_SIZE                    (0x400 - 0x8)
+
+/*
+ * MCU Control Registers
+ *
+ * The Zynq UltraScale+ Devices Register Reference documents the registers
+ * with an offset of 0x9000, which equals the size of the SRAM and one page
+ * gap. The driver handles SRAM and registers separately and, therefore, is
+ * oblivious of the offset.
+ */
+#define AL5_MCU_RESET                   0x0000
+#define AL5_MCU_RESET_SOFT              BIT(0)
+#define AL5_MCU_RESET_REGS              BIT(1)
+#define AL5_MCU_RESET_MODE              0x0004
+#define AL5_MCU_RESET_MODE_SLEEP        BIT(0)
+#define AL5_MCU_RESET_MODE_HALT         BIT(1)
+#define AL5_MCU_STA                     0x0008
+#define AL5_MCU_STA_SLEEP               BIT(0)
+#define AL5_MCU_WAKEUP                  0x000c
+
+#define AL5_ICACHE_ADDR_OFFSET_MSB      0x0010
+#define AL5_ICACHE_ADDR_OFFSET_LSB      0x0014
+#define AL5_DCACHE_ADDR_OFFSET_MSB      0x0018
+#define AL5_DCACHE_ADDR_OFFSET_LSB      0x001c
+
+#define AL5_MCU_INTERRUPT               0x0100
+#define AL5_ITC_CPU_IRQ_MSK             0x0104
+#define AL5_ITC_CPU_IRQ_CLR             0x0108
+#define AL5_ITC_CPU_IRQ_STA             0x010C
+#define AL5_ITC_CPU_IRQ_STA_TRIGGERED	BIT(0)
+
+#define AXI_ADDR_OFFSET_IP              0x0208
+
+/*
+ * TODO It seems that the MCU accesses the system memory with a 2G offset
+ * compared to CPU physical addresses.
+ */
+#define MCU_CACHE_OFFSET SZ_2G
+
+/*
+ * TODO The hardware encoder does not write SPS/PPS NAL units, but relies on
+ * the driver to add these. Thus, we need to save some space in the beginning
+ * of the stream buffers for these NAL units.
+ *
+ * The encoder will add the offset before writing the stream data.
+ * Unfortunately, the data does not start exactly at that offset, but a bit
+ * later and we need to add a filler nal.
+ */
+#define ENCODER_STREAM_OFFSET SZ_64
+
+/*
+ * TODO The downstream driver version 2018.02 uses 16M for the suballocator.
+ * I don't know what this memory is used for and how much is actually
+ * required. Firmware version 2018.02 already uses 32M.
+ */
+#define MCU_SUBALLOCATOR_SIZE SZ_16M
+
+/*
+ * Copied from the downstream driver.
+ */
+#define AL_OPT_WPP			BIT(0)
+#define AL_OPT_TILE			BIT(1)
+#define AL_OPT_LF			BIT(2)
+#define AL_OPT_LF_X_SLICE		BIT(3)
+#define AL_OPT_LF_X_TILE		BIT(4)
+#define AL_OPT_SCL_LST			BIT(5)
+#define AL_OPT_CONST_INTRA_PRED		BIT(6)
+#define AL_OPT_QP_TAB_RELATIVE		BIT(7)
+#define AL_OPT_FIX_PREDICTOR		BIT(8)
+#define AL_OPT_CUSTOM_LDA		BIT(9)
+#define AL_OPT_ENABLE_AUTO_QP		BIT(10)
+#define AL_OPT_ADAPT_AUTO_QP		BIT(11)
+#define AL_OPT_TRANSFO_SKIP		BIT(13)
+#define AL_OPT_FORCE_REC		BIT(15)
+#define AL_OPT_FORCE_MV_OUT		BIT(16)
+#define AL_OPT_FORCE_MV_CLIP		BIT(17)
+#define AL_OPT_LOWLAT_SYNC		BIT(18)
+#define AL_OPT_LOWLAT_INT		BIT(19)
+#define AL_OPT_RDO_COST_MODE		BIT(20)
+
+/*
+ * Slice types reported in the mcu_msg_encode_frame_response message.
+ */
+#define AL_ENC_SLICE_TYPE_B             0
+#define AL_ENC_SLICE_TYPE_P             1
+#define AL_ENC_SLICE_TYPE_I             2
+
+#define SIZE_MACROBLOCK 16
+
+static int debug = 0;
+module_param(debug, int, 0644);
+MODULE_PARM_DESC(debug, "Debug level (0-2)");
+
+static bool poison_capture_buffers = false;
+module_param(poison_capture_buffers, bool, 0644);
+MODULE_PARM_DESC(poison_capture_buffers,
+		 "Poison capture buffer before writing stream data");
+
+struct allegro_buffer {
+	void *vaddr;
+	dma_addr_t paddr;
+	size_t size;
+	struct list_head head;
+};
+
+struct allegro_channel;
+
+struct allegro_mbox {
+	unsigned int head;
+	unsigned int tail;
+	unsigned int data;
+	size_t size;
+	/* protect mailbox from simultaneous accesses */
+	struct mutex lock;
+};
+
+struct allegro_dev {
+	struct v4l2_device v4l2_dev;
+	struct video_device video_dev;
+	struct v4l2_m2m_dev *m2m_dev;
+	struct platform_device *plat_dev;
+
+	/* mutex protecting vb2_queue structure */
+	struct mutex lock;
+
+	struct regmap *regmap;
+	struct regmap *sram;
+
+	struct allegro_buffer firmware;
+	struct allegro_buffer suballocator;
+
+	struct completion init_complete;
+
+	/* The mailbox interface */
+	struct allegro_mbox mbox_command;
+	struct allegro_mbox mbox_status;
+
+	/*
+	 * The downstream driver limits the users to 64 users, thus I can use
+	 * a bitfield for the user_ids that are in use. See also user_id in
+	 * struct allegro_channel.
+	 */
+	unsigned long channel_user_ids;
+	struct list_head channels;
+};
+
+static struct regmap_config allegro_regmap_config = {
+	.name = "regmap",
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = 0xfff,
+	.cache_type = REGCACHE_NONE,
+};
+
+static struct regmap_config allegro_sram_config = {
+	.name = "sram",
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = 0x7fff,
+	.cache_type = REGCACHE_NONE,
+};
+
+#define fh_to_channel(__fh) container_of(__fh, struct allegro_channel, fh)
+
+struct allegro_channel {
+	struct allegro_dev *dev;
+	struct v4l2_fh fh;
+	struct v4l2_ctrl_handler ctrl_handler;
+
+	unsigned int width;
+	unsigned int height;
+	unsigned int stride;
+
+	enum v4l2_colorspace colorspace;
+	enum v4l2_ycbcr_encoding ycbcr_enc;
+	enum v4l2_quantization quantization;
+	enum v4l2_xfer_func xfer_func;
+
+	u32 pixelformat;
+	unsigned int sizeimage_raw;
+
+	u32 codec;
+	enum v4l2_mpeg_video_h264_profile profile;
+	enum v4l2_mpeg_video_h264_level level;
+	unsigned int sizeimage_encoded;
+
+	enum v4l2_mpeg_video_bitrate_mode bitrate_mode;
+	unsigned int bitrate;
+	unsigned int bitrate_peak;
+	unsigned int cpb_size;
+	unsigned int gop_size;
+
+	/* user_id is used to identify the channel during CREATE_CHANNEL */
+	/* not sure, what to set here and if this is actually required */
+	int user_id;
+	/* channel_id is set by the mcu and used by all later commands */
+	int mcu_channel_id;
+
+	struct list_head buffers_reference;
+	struct list_head buffers_intermediate;
+
+	struct list_head list;
+	struct completion completion;
+
+	bool created;
+	bool stop;
+};
+
+struct fw_info {
+	unsigned int id;
+	char *version;
+};
+
+static const struct fw_info supported_firmware[] = {
+	{
+		.id = 18296,
+		.version = "v2018.2",
+	},
+};
+
+enum mcu_msg_type {
+	MCU_MSG_TYPE_INIT = 0x0000,
+	MCU_MSG_TYPE_CREATE_CHANNEL = 0x0005,
+	MCU_MSG_TYPE_DESTROY_CHANNEL = 0x0006,
+	MCU_MSG_TYPE_ENCODE_FRAME = 0x0007,
+	MCU_MSG_TYPE_PUT_STREAM_BUFFER = 0x0012,
+	MCU_MSG_TYPE_PUSH_BUFFER_INTERMEDIATE = 0x000e,
+	MCU_MSG_TYPE_PUSH_BUFFER_REFERENCE = 0x000f,
+};
+
+static const char *msg_type_name(enum mcu_msg_type type)
+{
+	static char buf[9];
+
+	switch (type) {
+	case MCU_MSG_TYPE_INIT:
+		return "INIT";
+	case MCU_MSG_TYPE_CREATE_CHANNEL:
+		return "CREATE_CHANNEL";
+	case MCU_MSG_TYPE_DESTROY_CHANNEL:
+		return "DESTROY_CHANNEL";
+	case MCU_MSG_TYPE_ENCODE_FRAME:
+		return "ENCODE_FRAME";
+	case MCU_MSG_TYPE_PUT_STREAM_BUFFER:
+		return "PUT_STREAM_BUFFER";
+	case MCU_MSG_TYPE_PUSH_BUFFER_INTERMEDIATE:
+		return "PUSH_BUFFER_INTERMEDIATE";
+	case MCU_MSG_TYPE_PUSH_BUFFER_REFERENCE:
+		return "PUSH_BUFFER_REFERENCE";
+	default:
+		snprintf(buf, sizeof(buf), "(0x%04x)", type);
+		return buf;
+	}
+}
+
+struct mcu_msg_header {
+	u16 length;		/* length of the body in bytes */
+	u16 type;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_init_request {
+	struct mcu_msg_header header;
+	u32 reserved0;		/* maybe a unused channel id */
+	u32 suballoc_dma;
+	u32 suballoc_size;
+	s32 l2_cache[3];
+} __attribute__ ((__packed__));
+
+struct mcu_msg_init_reply {
+	struct mcu_msg_header header;
+	u32 reserved0;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_create_channel {
+	struct mcu_msg_header header;
+	u32 user_id;
+	u16 width;
+	u16 height;
+	u32 format;
+	u32 colorspace;
+	u32 src_mode;
+	u8 profile;
+	u16 constraint_set_flags;
+	s8 codec;
+	u16 level;
+	u16 tier;
+	u32 sps_param;
+	u32 pps_param;
+	u32 enc_option;
+	s8 beta_offset;
+	s8 tc_offset;
+	u16 reserved10;
+	u32 unknown11;
+	u32 unknown12;
+	u16 num_slices;
+	u16 prefetch_auto;
+	u32 prefetch_mem_offset;
+	u32 prefetch_mem_size;
+	u16 clip_hrz_range;
+	u16 clip_vrt_range;
+	u16 me_range[4];
+	u8 max_cu_size;
+	u8 min_cu_size;
+	u8 max_tu_size;
+	u8 min_tu_size;
+	u8 max_transfo_depth_inter;
+	u8 max_transfo_depth_intra;
+	u16 reserved20;
+	u32 entropy_mode;
+	u32 wp_mode;
+	/* rate control param */
+	u32 rate_control_mode;
+	u32 initial_rem_delay;
+	u32 cpb_size;
+	u16 framerate;
+	u16 clk_ratio;
+	u32 target_bitrate;
+	u32 max_bitrate;
+	u16 initial_qp;
+	u16 min_qp;
+	u16 max_qp;
+	s16 ip_delta;
+	s16 pb_delta;
+	u16 golden_ref;
+	u16 golden_delta;
+	u16 golden_ref_frequency;
+	u32 rate_control_option;
+	/* gop param */
+	u32 gop_ctrl_mode;
+	u32 freq_ird;
+	u32 freq_lt;
+	u32 gdr_mode;
+	u32 gop_length;
+	u32 unknown39;
+	u32 subframe_latency;
+	u32 lda_control_mode;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_create_channel_response {
+	struct mcu_msg_header header;
+	u32 channel_id;
+	u32 user_id;
+	u32 options;
+	u32 num_core;
+	u32 pps_param;
+	u32 int_buffers_count;
+	u32 int_buffers_size;
+	u32 rec_buffers_count;
+	u32 rec_buffers_size;
+	u32 reserved;
+	u32 error_code;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_destroy_channel {
+	struct mcu_msg_header header;
+	u32 channel_id;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_destroy_channel_response {
+	struct mcu_msg_header header;
+	u32 channel_id;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_push_buffers_internal_buffer {
+	u32 dma_addr;
+	u32 mcu_addr;
+	u32 size;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_push_buffers_internal {
+	struct mcu_msg_header header;
+	u32 channel_id;
+	/* variable length array of mcu_msg_put_internal_buffers_buffer */
+} __attribute__ ((__packed__));
+
+struct mcu_msg_put_stream_buffer {
+	struct mcu_msg_header header;
+	u32 channel_id;
+	u32 dma_addr;
+	u32 mcu_addr;
+	u32 size;
+	u32 offset;
+	u64 stream_id;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_encode_frame {
+	struct mcu_msg_header header;
+	u32 channel_id;
+	u32 reserved;
+	u32 encoding_options;
+	s16 pps_qp;
+	u16 padding;
+	u64 user_param;
+	u64 src_handle;
+	u32 request_options;
+	/* u32 scene_change_delay (optional) */
+	/* rate control param (optional) */
+	/* gop param (optional) */
+	u32 src_y;
+	u32 src_uv;
+	u32 stride;
+	u32 ep2;
+	u64 ep2_v;
+} __attribute__ ((__packed__));
+
+struct mcu_msg_encode_frame_response {
+	struct mcu_msg_header header;
+	u32 channel_id;
+	u64 stream_id;		/* see mcu_msg_put_stream_buffer */
+	u64 user_param;		/* see mcu_msg_encode_frame */
+	u64 src_handle;		/* see mcu_msg_encode_frame */
+	u16 skip;
+	u16 is_ref;
+	u32 initial_removal_delay;
+	u32 dpb_output_delay;
+	u32 size;
+	u32 frame_tag_size;
+	s32 stuffing;
+	s32 filler;
+	u16 num_column;
+	u16 num_row;
+	u16 qp;
+	u8 num_ref_idx_l0;
+	u8 num_ref_idx_l1;
+	u32 partition_table_offset;
+	s32 partition_table_size;
+	u32 sum_complex;
+	s32 tile_width[4];	/* TODO AL_ENC_NUM_CORES = 4 */
+	s32 tile_height[22];	/* TODO AL_MAX_ROWS_TILE = 22 */
+	u32 error_code;
+	u32 slice_type;
+	u32 pic_struct;
+	u8 is_idr;
+	u8 is_first_slice;
+	u8 is_last_slice;
+	u8 reserved;
+	u16 pps_qp;
+	u16 reserved1;
+	u32 reserved2;
+} __attribute__ ((__packed__));
+
+/* Helper functions for channel and user operations */
+
+static unsigned long allegro_next_user_id(struct allegro_dev *dev)
+{
+	if (dev->channel_user_ids == ~0UL)
+		return -EBUSY;
+
+	return ffz(dev->channel_user_ids);
+}
+
+static struct allegro_channel *
+allegro_find_channel_by_user_id(struct allegro_dev *dev,
+				unsigned int user_id)
+{
+	struct allegro_channel *channel;
+
+	list_for_each_entry(channel, &dev->channels, list) {
+		if (channel->user_id == user_id)
+			return channel;
+	}
+
+	return ERR_PTR(-EINVAL);
+}
+
+static struct allegro_channel *
+allegro_find_channel_by_channel_id(struct allegro_dev *dev,
+				   unsigned int channel_id)
+{
+	struct allegro_channel *channel;
+
+	list_for_each_entry(channel, &dev->channels, list) {
+		if (channel->mcu_channel_id == channel_id)
+			return channel;
+	}
+
+	return ERR_PTR(-EINVAL);
+}
+
+static unsigned int estimate_stream_size(unsigned int width, unsigned int height)
+{
+	int num_blocks = DIV_ROUND_UP(width, 64) * DIV_ROUND_UP(height, 64);
+	int pcm_size = SZ_1K + SZ_512;
+	int offset = ENCODER_STREAM_OFFSET;
+	int partition_table = SZ_256;
+
+	return round_up(offset + num_blocks * pcm_size + partition_table, 32);
+}
+
+static enum v4l2_mpeg_video_h264_level
+select_minimum_h264_level(unsigned int width, unsigned int height)
+{
+	unsigned int pic_width_in_mb = DIV_ROUND_UP(width, SIZE_MACROBLOCK);
+	unsigned int frame_height_in_mb = DIV_ROUND_UP(height, SIZE_MACROBLOCK);
+	unsigned int frame_size_in_mb = pic_width_in_mb * frame_height_in_mb;
+	enum v4l2_mpeg_video_h264_level level = V4L2_MPEG_VIDEO_H264_LEVEL_4_0;
+
+	/*
+	 * TODO This a very rudimentary implementation of the level limits
+	 * specified in Annex A.3.1, which for now only respects the frame
+	 * size.
+	 */
+
+	if (frame_size_in_mb <= 99)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_1_0;
+	else if (frame_size_in_mb <= 396)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_1_1;
+	else if (frame_size_in_mb <= 792)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_2_1;
+	else if (frame_size_in_mb <= 1620)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_2_2;
+	else if (frame_size_in_mb <= 3600)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_3_1;
+	else if (frame_size_in_mb <= 5120)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_3_2;
+	else if (frame_size_in_mb <= 8192)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_4_0;
+	else if (frame_size_in_mb <= 8704)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_4_2;
+	else if (frame_size_in_mb <= 22080)
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_5_0;
+	else
+		level = V4L2_MPEG_VIDEO_H264_LEVEL_5_1;
+
+	/*
+	 * The encoder supports maximum 4k resolution, which equals a frame
+	 * size of 32400 macro blocks and is supported by Level 5.1 (36864
+	 * macro blocks. Therefore, defaulting to Level 5.1 isn't that bad.
+	 */
+
+	return level;
+}
+
+static unsigned int maximum_bitrate(enum v4l2_mpeg_video_h264_level level)
+{
+	switch (level) {
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_0:
+		return 64000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1B:
+		return 128000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_1:
+		return 192000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_2:
+		return 384000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_3:
+		return 768000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_0:
+		return 2000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_1:
+		return 4000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_2:
+		return 4000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_0:
+		return 10000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_1:
+		return 14000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_2:
+		return 20000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_0:
+		return 20000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_1:
+		return 50000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_2:
+		return 50000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_5_0:
+		return 135000000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_5_1:
+	default:
+		return 240000000;
+	}
+}
+
+static unsigned int maximum_cpb_size(enum v4l2_mpeg_video_h264_level level)
+{
+	switch (level) {
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_0:
+		return 175;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1B:
+		return 350;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_1:
+		return 500;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_2:
+		return 1000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_3:
+		return 2000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_0:
+		return 2000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_1:
+		return 4000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_2:
+		return 4000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_0:
+		return 10000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_1:
+		return 14000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_2:
+		return 20000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_0:
+		return 25000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_1:
+		return 62500;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_2:
+		return 62500;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_5_0:
+		return 135000;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_5_1:
+	default:
+		return 240000;
+	}
+}
+
+static const struct fw_info *allegro_get_firmware_info(struct allegro_dev *dev,
+						       const struct firmware *fw)
+{
+	int i;
+	unsigned int id = fw->size;
+
+	for (i = 0; i < ARRAY_SIZE(supported_firmware); i++)
+		if (supported_firmware[i].id == id)
+			return &supported_firmware[i];
+
+	return NULL;
+}
+
+/*
+ * Buffers that are used internally by the MCU.
+ */
+
+int allegro_alloc_buffer(struct allegro_dev *dev,
+			 struct allegro_buffer *buffer, size_t size)
+{
+	buffer->vaddr = dma_alloc_coherent(&dev->plat_dev->dev, size,
+					   &buffer->paddr, GFP_KERNEL);
+	if (!buffer->vaddr)
+		return -ENOMEM;
+	buffer->size = size;
+
+	return 0;
+}
+
+void allegro_free_buffer(struct allegro_dev *dev, struct allegro_buffer *buffer)
+{
+	if (buffer->vaddr) {
+		dma_free_coherent(&dev->plat_dev->dev, buffer->size,
+				  buffer->vaddr, buffer->paddr);
+		buffer->vaddr = NULL;
+		buffer->size = 0;
+	}
+}
+
+/*
+ * Mailbox interface to send messages to the MCU.
+ */
+
+static int allegro_mbox_init(struct allegro_dev *dev,
+			     struct allegro_mbox *mbox,
+			     unsigned int base, size_t size)
+{
+	if (!mbox)
+		return -EINVAL;
+
+	mbox->head = base;
+	mbox->tail = base + 0x4;
+	mbox->data = base + 0x8;
+	mbox->size = size;
+	mutex_init(&mbox->lock);
+
+	regmap_write(dev->sram, mbox->head, 0);
+	regmap_write(dev->sram, mbox->tail, 0);
+
+	return 0;
+}
+
+static int allegro_mbox_write(struct allegro_dev *dev,
+			      struct allegro_mbox *mbox, void *src, size_t size)
+{
+	struct mcu_msg_header *header = src;
+	unsigned int tail;
+	size_t size_no_wrap;
+	int err = 0;
+
+	if (!src)
+		return -EINVAL;
+
+	if (size > mbox->size) {
+		v4l2_err(&dev->v4l2_dev,
+			 "message (%lu bytes) to large for mailbox (%lu bytes)\n",
+			 size, mbox->size);
+		return -EINVAL;
+	}
+
+	if (header->length != size - sizeof(*header)) {
+		v4l2_err(&dev->v4l2_dev,
+			 "invalid message length: %u bytes (expected %lu bytes)\n",
+			 header->length, size - sizeof(*header));
+		return -EINVAL;
+	}
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		"write command message: type %s, body length %d\n",
+		msg_type_name(header->type), header->length);
+
+	mutex_lock(&mbox->lock);
+	regmap_read(dev->sram, mbox->tail, &tail);
+	if (tail > mbox->size) {
+		v4l2_err(&dev->v4l2_dev,
+			 "invalid tail (0x%x): must be smaller than mailbox size (0x%lx)\n",
+			 tail, mbox->size);
+		err = -EIO;
+		goto out;
+	}
+	size_no_wrap = min(size, mbox->size - (size_t)tail);
+	regmap_bulk_write(dev->sram, mbox->data + tail, src, size_no_wrap / 4);
+	regmap_bulk_write(dev->sram, mbox->data,
+			  src + size_no_wrap, (size - size_no_wrap) / 4);
+	regmap_write(dev->sram, mbox->tail, (tail + size) % mbox->size);
+
+out:
+	mutex_unlock(&mbox->lock);
+
+	return err;
+}
+
+static ssize_t allegro_mbox_read(struct allegro_dev *dev,
+				 struct allegro_mbox *mbox,
+				 void *dst, size_t nbyte)
+{
+	struct mcu_msg_header *header;
+	unsigned int head;
+	ssize_t size;
+	size_t body_no_wrap;
+
+	regmap_read(dev->sram, mbox->head, &head);
+	if (head > mbox->size) {
+		v4l2_err(&dev->v4l2_dev,
+			 "invalid head (0x%x): must be smaller than mailbox size (0x%lx)\n",
+			 head, mbox->size);
+		return -EIO;
+	}
+
+	/* Assume that the header does not wrap. */
+	regmap_bulk_read(dev->sram, mbox->data + head,
+			 dst, sizeof(*header) / 4);
+	header = dst;
+	size = header->length + sizeof(*header);
+	if (size > mbox->size || size & 0x3) {
+		v4l2_err(&dev->v4l2_dev,
+			 "invalid message length: %lu bytes (maximum %lu bytes)\n",
+			 header->length + sizeof(*header), mbox->size);
+		return -EIO;
+	}
+	if (size > nbyte) {
+		v4l2_err(&dev->v4l2_dev,
+			 "destination buffer too small: %lu bytes (need %lu bytes)\n",
+			 nbyte, size);
+		return -EINVAL;
+	}
+
+	/*
+	 * The message might wrap within the mailbox. If the message does not
+	 * wrap, the first read will read the entire message, otherwise the
+	 * first read will read message until the end of the mailbox and the
+	 * second read will read the remaining bytes from the beginning of the
+	 * mailbox.
+	 *
+	 * Skip the header, as was already read to get the size of the body.
+	 */
+	body_no_wrap = min((size_t)header->length,
+			   (mbox->size - (head + sizeof(*header))));
+	regmap_bulk_read(dev->sram, mbox->data + head + sizeof(*header),
+			 dst + sizeof(*header), body_no_wrap / 4);
+	regmap_bulk_read(dev->sram, mbox->data,
+			 dst + sizeof(*header) + body_no_wrap,
+			 (header->length - body_no_wrap) / 4);
+
+	regmap_write(dev->sram, mbox->head, (head + size) % mbox->size);
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		"read status message: type %s, body length %d\n",
+		msg_type_name(header->type), header->length);
+
+	return size;
+}
+
+static void allegro_mcu_interrupt(struct allegro_dev *dev)
+{
+	regmap_write(dev->regmap, AL5_MCU_INTERRUPT, BIT(0));
+}
+
+static void allegro_mcu_send_init(struct allegro_dev *dev,
+				  dma_addr_t suballoc_dma, size_t suballoc_size)
+{
+	struct mcu_msg_init_request msg;
+
+	msg.header.type = MCU_MSG_TYPE_INIT;
+	msg.header.length = sizeof(msg) - sizeof(msg.header);
+	msg.reserved0 = 0;
+	msg.suballoc_dma = lower_32_bits(suballoc_dma) | MCU_CACHE_OFFSET;
+	msg.suballoc_size = suballoc_size;
+
+	/* TODO Add L2 cache support. */
+	msg.l2_cache[0] = -1;
+	msg.l2_cache[1] = -1;
+	msg.l2_cache[2] = -1;
+
+	allegro_mbox_write(dev, &dev->mbox_command, &msg, sizeof(msg));
+	allegro_mcu_interrupt(dev);
+}
+
+static u32 v4l2_pixelformat_to_mcu_format(u32 pixelformat)
+{
+	switch (pixelformat) {
+	case V4L2_PIX_FMT_NV12:
+		/* AL_420_8BITS: 0x100 -> NV12, 0x88 -> 8 bit */
+		return 0x100 | 0x88;
+	default:
+		return -EINVAL;
+	}
+}
+
+static u32 v4l2_colorspace_to_mcu_colorspace(enum v4l2_colorspace colorspace)
+{
+	switch (colorspace) {
+	case V4L2_COLORSPACE_REC709:
+		return 2;
+	case V4L2_COLORSPACE_SMPTE170M:
+		return 3;
+	case V4L2_COLORSPACE_SMPTE240M:
+		return 4;
+	case V4L2_COLORSPACE_SRGB:
+		return 7;
+	default:
+		/* UNKNOWN */
+		return 0;
+	}
+}
+
+static s8 v4l2_pixelformat_to_mcu_codec(u32 pixelformat)
+{
+	switch (pixelformat) {
+	case V4L2_PIX_FMT_H264:
+	default:
+		return 1;
+	}
+}
+
+static u8 v4l2_profile_to_mcu_profile(enum v4l2_mpeg_video_h264_profile profile)
+{
+	switch (profile) {
+	case V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE:
+	default:
+		return 66;
+	}
+}
+
+static u16 v4l2_level_to_mcu_level(enum v4l2_mpeg_video_h264_level level)
+{
+	switch (level) {
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_0:
+		return 10;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_1:
+		return 11;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_2:
+		return 12;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_1_3:
+		return 13;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_0:
+		return 20;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_1:
+		return 21;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_2_2:
+		return 22;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_0:
+		return 30;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_1:
+		return 31;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_3_2:
+		return 32;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_0:
+		return 40;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_1:
+		return 41;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_4_2:
+		return 42;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_5_0:
+		return 50;
+	case V4L2_MPEG_VIDEO_H264_LEVEL_5_1:
+	default:
+		return 51;
+	}
+}
+
+static u32 v4l2_bitrate_mode_to_mcu_mode(enum v4l2_mpeg_video_bitrate_mode mode)
+{
+	switch (mode) {
+	case V4L2_MPEG_VIDEO_BITRATE_MODE_VBR:
+		return 2;
+	case V4L2_MPEG_VIDEO_BITRATE_MODE_CBR:
+	default:
+		return 1;
+	}
+}
+
+static void allegro_mcu_send_create_channel(struct allegro_dev *dev,
+					    struct allegro_channel *channel)
+{
+	struct mcu_msg_create_channel msg;
+
+	msg.header.type = MCU_MSG_TYPE_CREATE_CHANNEL;
+	msg.header.length = sizeof(msg) - sizeof(msg.header);
+
+	msg.user_id = channel->user_id;
+	msg.width = channel->width;
+	msg.height = channel->height;
+	msg.format = v4l2_pixelformat_to_mcu_format(channel->pixelformat);
+	msg.colorspace = v4l2_colorspace_to_mcu_colorspace(channel->colorspace);
+	msg.src_mode = 0x0;
+	msg.profile = v4l2_profile_to_mcu_profile(channel->profile);
+	msg.constraint_set_flags = BIT(1);
+	msg.codec = v4l2_pixelformat_to_mcu_codec(channel->codec);
+	msg.level = v4l2_level_to_mcu_level(channel->level);
+	msg.tier = 0;
+	msg.sps_param = BIT(20) | 0x4a;
+	msg.pps_param = BIT(2);
+	msg.enc_option = AL_OPT_RDO_COST_MODE | AL_OPT_LF_X_TILE |
+			 AL_OPT_LF_X_SLICE | AL_OPT_LF;
+	msg.beta_offset = -1;
+	msg.tc_offset = -1;
+	msg.reserved10 = 0x0000;
+	msg.unknown11 = 0x00000000;
+	msg.unknown12 = 0x00000000;
+	msg.num_slices = 1;
+	msg.prefetch_auto = 0x0000;	/* false */
+	msg.prefetch_mem_offset = 0x00000000;
+	msg.prefetch_mem_size = 0x00000000;
+	msg.clip_vrt_range = 0x0000;
+	msg.clip_hrz_range = 0x0000;
+	msg.me_range[0] = 8;
+	msg.me_range[1] = 8;
+	msg.me_range[2] = 16;
+	msg.me_range[3] = 16;
+	msg.max_cu_size = ilog2(SIZE_MACROBLOCK);
+	msg.min_cu_size = ilog2(8);
+	msg.max_tu_size = 2;
+	msg.min_tu_size = 2;
+	msg.max_transfo_depth_intra = 1;
+	msg.max_transfo_depth_inter = 1;
+	msg.reserved20 = 0x0000;
+	msg.entropy_mode = 0x00000000;
+	msg.wp_mode = 0x00000000;
+	msg.rate_control_mode = v4l2_bitrate_mode_to_mcu_mode(channel->bitrate_mode);
+	/* Shall be ]0;cpb_size in  90 kHz units]. Use maximum value for now. */
+	msg.initial_rem_delay = ((channel->cpb_size * 1000) / channel->bitrate_peak) * 90000;
+	/* Encoder expects cpb_size in units of a 90 kHz clock. */
+	msg.cpb_size = ((channel->cpb_size * 1000) / channel->bitrate_peak) * 90000;
+	msg.framerate = 25;
+	msg.clk_ratio = 1000;
+	msg.target_bitrate = channel->bitrate;
+	msg.max_bitrate = channel->bitrate_peak;
+	msg.initial_qp = 25;
+	msg.min_qp = 10;
+	msg.max_qp = 51;
+	msg.ip_delta = -1;
+	msg.pb_delta = -1;
+	msg.golden_ref = 0;
+	msg.golden_delta = 2;
+	msg.golden_ref_frequency = 10;
+	msg.rate_control_option = 0x00000000;
+	msg.gop_ctrl_mode = 0x00000000;
+	msg.freq_ird = 0x7fffffff;	/* MAX_INT??? */
+	msg.freq_lt = 0;
+	msg.gdr_mode = 0x00000000;
+	msg.gop_length = channel->gop_size;
+	msg.unknown39 = 0;
+	msg.subframe_latency = 0x00000000;	/* ??? */
+	msg.lda_control_mode = 0x700d0000;	/* ??? */
+
+	allegro_mbox_write(dev, &dev->mbox_command, &msg, sizeof(msg));
+	allegro_mcu_interrupt(dev);
+}
+
+static int allegro_mcu_send_destroy_channel(struct allegro_dev *dev,
+					    struct allegro_channel *channel)
+{
+	struct mcu_msg_destroy_channel msg;
+
+	msg.header.type = MCU_MSG_TYPE_DESTROY_CHANNEL;
+	msg.header.length = sizeof(msg) - sizeof(msg.header);
+
+	msg.channel_id = channel->mcu_channel_id;
+
+	allegro_mbox_write(dev, &dev->mbox_command, &msg, sizeof(msg));
+	allegro_mcu_interrupt(dev);
+
+	return 0;
+}
+
+static int allegro_mcu_send_put_stream_buffer(struct allegro_dev *dev,
+					      struct allegro_channel *channel,
+					      struct allegro_buffer buffer)
+{
+	struct mcu_msg_put_stream_buffer msg;
+	/*
+	 * TODO It seems that stream_id is not used, but allows to identify
+	 * the used stream buffer from the ENCODE_FRAME response.
+	 */
+	int stream_id = 0;
+
+	msg.header.type = MCU_MSG_TYPE_PUT_STREAM_BUFFER;
+	msg.header.length = sizeof(msg) - sizeof(msg.header);
+
+	msg.channel_id = channel->mcu_channel_id;
+	msg.dma_addr = buffer.paddr;
+	msg.mcu_addr = buffer.paddr | MCU_CACHE_OFFSET;
+	msg.size = buffer.size;
+	msg.offset = ENCODER_STREAM_OFFSET;
+	msg.stream_id = stream_id;
+
+	allegro_mbox_write(dev, &dev->mbox_command, &msg, sizeof(msg));
+	allegro_mcu_interrupt(dev);
+
+	return 0;
+}
+
+static void allegro_mcu_send_encode_frame(struct allegro_dev *dev,
+					  struct allegro_channel *channel,
+					  dma_addr_t src_y, dma_addr_t src_uv)
+{
+	struct mcu_msg_encode_frame msg;
+
+	msg.header.type = MCU_MSG_TYPE_ENCODE_FRAME;
+	/*
+	 * TODO Calculating the length of the message by using the struct size
+	 * breaks once the optional parameters are used.
+	 */
+	msg.header.length = sizeof(msg) - sizeof(msg.header);
+
+	msg.channel_id = channel->mcu_channel_id;
+	msg.encoding_options = 0x2;	/* AL_OPT_FORCE_LOAD */
+	msg.pps_qp = 26;	/* The SliceQP are relative to 26 */
+	msg.padding = 0x0;
+	/*
+	 * TODO It seems that user_param and src_handle are not used by the
+	 * mcu, but allow to relate the response message to the request.
+	 */
+	msg.user_param = 0;
+	msg.src_handle = 0;
+	msg.request_options = 0x0;	/* AL_NO_OPT */
+
+	msg.src_y = src_y;
+	msg.src_uv = src_uv;
+	msg.stride = channel->stride;
+	msg.ep2 = 0x0;
+	msg.ep2_v = msg.ep2 | MCU_CACHE_OFFSET;
+
+	allegro_mbox_write(dev, &dev->mbox_command, &msg, sizeof(msg));
+	allegro_mcu_interrupt(dev);
+}
+
+static int allegro_mcu_wait_for_init_timeout(struct allegro_dev *dev,
+					     unsigned long timeout_ms)
+{
+	unsigned long tmo;
+
+	tmo = wait_for_completion_timeout(&dev->init_complete,
+					  msecs_to_jiffies(timeout_ms));
+	if (tmo == 0)
+		return -ETIMEDOUT;
+
+	reinit_completion(&dev->init_complete);
+	return 0;
+}
+
+static int allegro_mcu_push_buffer_internal(struct allegro_channel *channel,
+					    enum mcu_msg_type type)
+{
+	struct allegro_dev *dev = channel->dev;
+	struct mcu_msg_push_buffers_internal *msg;
+	struct mcu_msg_push_buffers_internal_buffer *buffer;
+	unsigned int num_buffers = 0;
+	unsigned int size;
+	struct allegro_buffer *al_buffer;
+	struct list_head *list;
+	int err;
+
+	if (channel->created)
+		return -EINVAL;
+
+	switch (type) {
+	case MCU_MSG_TYPE_PUSH_BUFFER_REFERENCE:
+		list = &channel->buffers_reference;
+		break;
+	case MCU_MSG_TYPE_PUSH_BUFFER_INTERMEDIATE:
+		list = &channel->buffers_intermediate;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	list_for_each_entry(al_buffer, list, head) {
+		num_buffers++;
+	}
+
+	size = sizeof(*msg) + num_buffers * sizeof(*buffer);
+
+	msg = kmalloc(size, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	msg->header.length = size - sizeof(msg->header);
+	msg->header.type = type;
+	msg->channel_id = channel->mcu_channel_id;
+
+	buffer =
+	    (struct mcu_msg_push_buffers_internal_buffer *)((char *)msg +
+							    sizeof(*msg));
+	list_for_each_entry(al_buffer, list, head) {
+		buffer->dma_addr = lower_32_bits(al_buffer->paddr);
+		buffer->mcu_addr =
+		    lower_32_bits(al_buffer->paddr) | MCU_CACHE_OFFSET;
+		buffer->size = al_buffer->size;
+		buffer++;
+	}
+
+	err = allegro_mbox_write(dev, &dev->mbox_command, msg, size);
+	if (err)
+		goto out;
+	allegro_mcu_interrupt(dev);
+
+out:
+	kfree(msg);
+	return err;
+}
+
+static int allegro_mcu_push_buffer_intermediate(struct allegro_channel *channel)
+{
+	return allegro_mcu_push_buffer_internal(channel,
+						MCU_MSG_TYPE_PUSH_BUFFER_INTERMEDIATE);
+}
+
+static int allegro_mcu_push_buffer_reference(struct allegro_channel *channel)
+{
+	return allegro_mcu_push_buffer_internal(channel,
+						MCU_MSG_TYPE_PUSH_BUFFER_REFERENCE);
+}
+
+static int allocate_buffers_internal(struct allegro_channel *channel,
+				     struct list_head *list,
+				     size_t n, size_t size)
+{
+	struct allegro_dev *dev = channel->dev;
+	unsigned int i;
+	int err;
+	struct allegro_buffer *buffer, *tmp;
+
+	for (i = 0; i < n; i++) {
+		buffer = kmalloc(sizeof(*buffer), GFP_KERNEL);
+		if (!buffer) {
+			err = -ENOMEM;
+			goto err;
+		}
+		INIT_LIST_HEAD(&buffer->head);
+
+		err = allegro_alloc_buffer(dev, buffer, size);
+		if (err)
+			goto err;
+		list_add(&buffer->head, list);
+	}
+
+	return 0;
+
+err:
+	list_for_each_entry_safe(buffer, tmp, list, head) {
+		list_del(&buffer->head);
+		allegro_free_buffer(dev, buffer);
+		kfree(buffer);
+	}
+	return err;
+}
+
+static void destroy_buffers_internal(struct allegro_channel *channel,
+				     struct list_head *list)
+{
+	struct allegro_dev *dev = channel->dev;
+	struct allegro_buffer *buffer, *tmp;
+
+	list_for_each_entry_safe(buffer, tmp, list, head) {
+		list_del(&buffer->head);
+		allegro_free_buffer(dev, buffer);
+		kfree(buffer);
+	}
+}
+
+static void destroy_reference_buffers(struct allegro_channel *channel)
+{
+	return destroy_buffers_internal(channel, &channel->buffers_reference);
+}
+
+static void destroy_intermediate_buffers(struct allegro_channel *channel)
+{
+	return destroy_buffers_internal(channel,
+					&channel->buffers_intermediate);
+}
+
+static int allocate_intermediate_buffers(struct allegro_channel *channel,
+					 size_t n, size_t size)
+{
+	return allocate_buffers_internal(channel,
+					 &channel->buffers_intermediate,
+					 n, size);
+}
+
+static int allocate_reference_buffers(struct allegro_channel *channel,
+				      size_t n, size_t size)
+{
+	return allocate_buffers_internal(channel,
+					 &channel->buffers_reference,
+					 n, PAGE_ALIGN(size));
+}
+
+static void allegro_finish_frame(struct allegro_channel *channel,
+				 struct mcu_msg_encode_frame_response *msg)
+{
+	struct allegro_dev *dev = channel->dev;
+	struct vb2_v4l2_buffer *src_buf;
+	struct vb2_v4l2_buffer *dst_buf;
+	struct {
+		u32 offset;
+		u32 size;
+	} *partition;
+	enum vb2_buffer_state state = VB2_BUF_STATE_ERROR;
+
+	src_buf = v4l2_m2m_src_buf_remove(channel->fh.m2m_ctx);
+	v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_DONE);
+
+	dst_buf = v4l2_m2m_dst_buf_remove(channel->fh.m2m_ctx);
+
+	if (msg->error_code) {
+		v4l2_err(&dev->v4l2_dev,
+			 "channel %d: error while encoding frame: %x\n",
+			 channel->mcu_channel_id, msg->error_code);
+		goto err;
+	}
+
+	if (msg->partition_table_size != 1) {
+		v4l2_warn(&dev->v4l2_dev,
+			  "channel %d: only handling first partition table entry (%d entries)\n",
+			  channel->mcu_channel_id, msg->partition_table_size);
+	}
+
+	if (msg->partition_table_offset +
+	    msg->partition_table_size * sizeof(*partition) >
+	    vb2_plane_size(&dst_buf->vb2_buf, 0)) {
+		v4l2_err(&dev->v4l2_dev,
+			 "channel %d: partition table outside of dst_buf\n",
+			 channel->mcu_channel_id);
+		goto err;
+	}
+
+	partition =
+	    vb2_plane_vaddr(&dst_buf->vb2_buf, 0) + msg->partition_table_offset;
+	if (partition->offset + partition->size >
+	    vb2_plane_size(&dst_buf->vb2_buf, 0)) {
+		v4l2_err(&dev->v4l2_dev,
+			 "channel %d: encoded frame is outside of dst_buf (offset 0x%x, size 0x%x)\n",
+			 channel->mcu_channel_id, partition->offset,
+			 partition->size);
+		goto err;
+	}
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		"channel %d: encoded frame of size %d is at offset 0x%x\n",
+		channel->mcu_channel_id, partition->size, partition->offset);
+
+	/*
+	 * TODO The partition->offset differs from the ENCODER_STREAM_OFFSET.
+	 * Does the encoder add any data before its configured offset that we
+	 * need to handle?
+	 */
+
+	vb2_set_plane_payload(&dst_buf->vb2_buf, 0,
+			      partition->offset + partition->size);
+
+	state = VB2_BUF_STATE_DONE;
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "channel %d: encoded frame (%s%s, %d bytes)\n",
+		 channel->mcu_channel_id,
+		 msg->is_idr ? "IDR, " : "",
+		 msg->slice_type == AL_ENC_SLICE_TYPE_I ? "I slice" :
+		 msg->slice_type == AL_ENC_SLICE_TYPE_P ? "P slice" : "unknown",
+		 partition->size);
+
+err:
+	if (channel->stop) {
+		const struct v4l2_event eos_event = {
+			.type = V4L2_EVENT_EOS
+		};
+		dst_buf->flags |= V4L2_BUF_FLAG_LAST;
+		v4l2_event_queue_fh(&channel->fh, &eos_event);
+	}
+
+	v4l2_m2m_buf_done(dst_buf, state);
+	v4l2_m2m_job_finish(dev->m2m_dev, channel->fh.m2m_ctx);
+}
+
+static int allegro_handle_init(struct allegro_dev *dev,
+			       struct mcu_msg_init_reply *msg)
+{
+	complete(&dev->init_complete);
+
+	return 0;
+}
+
+static int
+allegro_handle_create_channel(struct allegro_dev *dev,
+			      struct mcu_msg_create_channel_response *msg)
+{
+	struct allegro_channel *channel;
+	int err = 0;
+
+	channel = allegro_find_channel_by_user_id(dev, msg->user_id);
+	if (IS_ERR(channel)) {
+		v4l2_warn(&dev->v4l2_dev,
+			  "received %s for unknown user %d\n",
+			  msg_type_name(msg->header.type),
+			  msg->user_id);
+		return -EINVAL;
+	}
+
+	if (msg->error_code) {
+		v4l2_err(&dev->v4l2_dev,
+			 "user %d: failed to create channel: error %d",
+			 channel->user_id, msg->error_code);
+		return -EINVAL;
+	}
+
+	channel->mcu_channel_id = msg->channel_id;
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "user %d: channel has channel id %d\n",
+		 channel->user_id, channel->mcu_channel_id);
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "channel %d: intermediate buffers: %d x %d bytes\n",
+		 channel->mcu_channel_id, msg->int_buffers_count,
+		 msg->int_buffers_size);
+	err = allocate_intermediate_buffers(channel, msg->int_buffers_count,
+					    msg->int_buffers_size);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "channel %d: failed to allocate intermediate buffers",
+			 channel->mcu_channel_id);
+		goto out;
+	}
+	allegro_mcu_push_buffer_intermediate(channel);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "channel %d: failed to push reference buffers",
+			 channel->mcu_channel_id);
+		goto out;
+	}
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "channel %d: reference buffers: %d x %d bytes\n",
+		 channel->mcu_channel_id, msg->rec_buffers_count,
+		 msg->rec_buffers_size);
+	err = allocate_reference_buffers(channel, msg->rec_buffers_count,
+					 msg->rec_buffers_size);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "channel %d: failed to allocate reference buffers",
+			 channel->mcu_channel_id);
+		goto out;
+	}
+	err = allegro_mcu_push_buffer_reference(channel);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "channel %d: failed to push reference buffers",
+			 channel->mcu_channel_id);
+		goto out;
+	}
+
+	channel->created = true;
+
+	/*
+	 * FIXME Need to send CHANNEL_DESTROY if we fail to allocate the
+	 * intermediate or reference buffers?
+	 */
+out:
+	complete(&channel->completion);
+	return err;
+}
+
+static int
+allegro_handle_destroy_channel(struct allegro_dev *dev,
+		struct mcu_msg_destroy_channel_response *msg)
+{
+	struct allegro_channel *channel;
+
+	channel = allegro_find_channel_by_channel_id(dev, msg->channel_id);
+	if (IS_ERR(channel)) {
+		v4l2_err(&dev->v4l2_dev,
+			 "received %s for unknown channel %d\n",
+			 msg_type_name(msg->header.type),
+			 msg->channel_id);
+		return -EINVAL;
+	}
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+			"user %d: vcu destroyed channel %d\n",
+			channel->user_id, channel->mcu_channel_id);
+	complete(&channel->completion);
+
+	return 0;
+}
+
+static int
+allegro_handle_encode_frame(struct allegro_dev *dev,
+			    struct mcu_msg_encode_frame_response *msg)
+{
+	struct allegro_channel *channel;
+
+	channel = allegro_find_channel_by_channel_id(dev, msg->channel_id);
+	if (IS_ERR(channel)) {
+		v4l2_err(&dev->v4l2_dev,
+			 "received %s for unknown channel %d\n",
+			 msg_type_name(msg->header.type),
+			 msg->channel_id);
+		return -EINVAL;
+	}
+
+	/* TODO Not sure if I really want to call this from here */
+	allegro_finish_frame(channel, msg);
+
+	return 0;
+}
+
+static int allegro_receive_message(struct allegro_dev *dev)
+{
+	struct mcu_msg_header *header;
+	ssize_t size;
+	int err = 0;
+
+	/*
+	 * FIXME header is struct mcu_msg_header, but we are allocating memory
+	 * for a struct mcu_msg_encode_one_frm_response, because we only need
+	 * to parse the header before we can determine the type and size of
+	 * the actual message and struct mcu_msg_encode_one_frm_response is
+	 * currently the largest message.
+	 */
+	header = kmalloc(sizeof(struct mcu_msg_encode_frame_response),
+			 GFP_KERNEL);
+	if (!header)
+		return -ENOMEM;
+
+	size = allegro_mbox_read(dev, &dev->mbox_status, header,
+				 sizeof(struct mcu_msg_encode_frame_response));
+	if (size < sizeof(*header)) {
+		v4l2_err(&dev->v4l2_dev,
+			 "invalid mbox message (%ld): must be at least %lu\n",
+			 size, sizeof(*header));
+		err = -EINVAL;
+		goto out;
+	}
+
+	switch(header->type) {
+	case MCU_MSG_TYPE_INIT:
+		err = allegro_handle_init(dev,
+				(struct mcu_msg_init_reply *) header);
+		break;
+	case MCU_MSG_TYPE_CREATE_CHANNEL:
+		err = allegro_handle_create_channel(dev,
+				(struct mcu_msg_create_channel_response *)header);
+		break;
+	case MCU_MSG_TYPE_DESTROY_CHANNEL:
+		err = allegro_handle_destroy_channel(dev,
+				(struct mcu_msg_destroy_channel_response *)header);
+		break;
+	case MCU_MSG_TYPE_ENCODE_FRAME:
+		err = allegro_handle_encode_frame(dev,
+				(struct mcu_msg_encode_frame_response *)header);
+		break;
+	default:
+		v4l2_warn(&dev->v4l2_dev,
+			  "%s: unknown message %s\n",
+			  __func__, msg_type_name(header->type));
+		err = -EINVAL;
+		break;
+	}
+
+out:
+	kfree(header);
+
+	return err;
+}
+
+irqreturn_t allegro_hardirq(int irq, void *data)
+{
+	struct allegro_dev *dev = data;
+	unsigned int status;
+
+	regmap_read(dev->regmap, AL5_ITC_CPU_IRQ_STA, &status);
+	if (!(status & AL5_ITC_CPU_IRQ_STA_TRIGGERED))
+		return IRQ_NONE;
+
+	regmap_write(dev->regmap, AL5_ITC_CPU_IRQ_CLR, status);
+
+	/*
+	 * The downstream driver suggests to wait until the clear has
+	 * propagated through the hardware, i.e.,
+	 *
+	 * 	!(read(AL5_ITC_CPU_IRQ_STA) & AL5_ITC_CPU_IRQ_STA_TRIGGERED)
+	 *
+	 * I assume that waiting for the interrupt to be cleared is not
+	 * required and just continue execution.
+	 */
+
+	return IRQ_WAKE_THREAD;
+}
+
+irqreturn_t allegro_irq_thread(int irq, void *data)
+{
+	struct allegro_dev *dev = data;
+
+	allegro_receive_message(dev);
+
+	return IRQ_HANDLED;
+}
+
+static void allegro_copy_firmware(struct allegro_dev *dev,
+				  const u8 * const buf, size_t size)
+{
+	int err = 0;
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		"copy mcu firmware (%lu B) to SRAM\n", size);
+	err = regmap_bulk_write(dev->sram, 0x0, buf, size / 4);
+	if (err)
+		v4l2_err(&dev->v4l2_dev,
+			 "failed to copy firmware: %d\n", err);
+}
+
+static void allegro_copy_fw_codec(struct allegro_dev *dev,
+				  const u8 * const buf, size_t size)
+{
+	int err;
+	dma_addr_t icache_offset, dcache_offset;
+
+	/*
+	 * The downstream allocates 600 KB for the codec firmware to have some
+	 * extra space for "possible extensions." My tests were fine with
+	 * allocating just enough memory for the actual firmware, but I am not
+	 * sure that the firmware really does not use the remaining space.
+	 */
+	err = allegro_alloc_buffer(dev, &dev->firmware, size);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "failed to allocate %lu bytes for firmware\n", size);
+		return;
+	}
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		"copy codec firmware (%ld B) to phys 0x%llx",
+		size, dev->firmware.paddr);
+	memcpy(dev->firmware.vaddr, buf, size);
+
+	regmap_write(dev->regmap, AXI_ADDR_OFFSET_IP,
+		     upper_32_bits(dev->firmware.paddr));
+
+	/*
+	 * TODO I am not sure what the icache and dcache offsets are doing.
+	 * Copy behavior from downstream driver for now.
+	 */
+	icache_offset = dev->firmware.paddr - MCU_CACHE_OFFSET;
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		"icache_offset: msb = 0x%x, lsb = 0x%x\n",
+		upper_32_bits(icache_offset), lower_32_bits(icache_offset));
+	regmap_write(dev->regmap, AL5_ICACHE_ADDR_OFFSET_MSB,
+		     upper_32_bits(icache_offset));
+	regmap_write(dev->regmap, AL5_ICACHE_ADDR_OFFSET_LSB,
+		     lower_32_bits(icache_offset));
+
+	dcache_offset =
+	    (dev->firmware.paddr & 0xffffffff00000000) - MCU_CACHE_OFFSET;
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		 "dcache_offset: msb = 0x%x, lsb = 0x%x\n",
+		 upper_32_bits(dcache_offset), lower_32_bits(dcache_offset));
+	regmap_write(dev->regmap, AL5_DCACHE_ADDR_OFFSET_MSB,
+		     upper_32_bits(dcache_offset));
+	regmap_write(dev->regmap, AL5_DCACHE_ADDR_OFFSET_LSB,
+		     lower_32_bits(dcache_offset));
+}
+
+/*
+ * Control functions for the MCU
+ */
+
+static void allegro_mcu_enable_interrupts(struct allegro_dev *dev)
+{
+	regmap_write(dev->regmap, AL5_ITC_CPU_IRQ_MSK, BIT(0));
+}
+
+static int allegro_mcu_wait_for_sleep(struct allegro_dev *dev)
+{
+	unsigned long timeout;
+	unsigned int status;
+
+	timeout = jiffies + msecs_to_jiffies(100);
+	while (regmap_read(dev->regmap, AL5_MCU_STA, &status) == 0 &&
+	       status != AL5_MCU_STA_SLEEP) {
+		if (time_after(jiffies, timeout))
+			return -ETIMEDOUT;
+		cpu_relax();
+	}
+
+	return 0;
+}
+
+static int allegro_mcu_start(struct allegro_dev *dev)
+{
+	unsigned long timeout;
+	unsigned int status;
+	int err;
+
+	err = regmap_write(dev->regmap, AL5_MCU_WAKEUP, BIT(0));
+	if (err)
+		return err;
+
+	timeout = jiffies + msecs_to_jiffies(100);
+	while (regmap_read(dev->regmap, AL5_MCU_STA, &status) == 0 &&
+	       status == AL5_MCU_STA_SLEEP) {
+		if (time_after(jiffies, timeout))
+			return -ETIMEDOUT;
+		cpu_relax();
+	}
+
+	err = regmap_write(dev->regmap, AL5_MCU_WAKEUP, 0);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int allegro_mcu_reset(struct allegro_dev *dev)
+{
+	int err;
+
+	err = regmap_write(dev->regmap,
+			   AL5_MCU_RESET_MODE, AL5_MCU_RESET_MODE_SLEEP);
+	if (err < 0)
+		return err;
+
+	err = regmap_write(dev->regmap, AL5_MCU_RESET, AL5_MCU_RESET_SOFT);
+	if (err < 0)
+		return err;
+
+	return allegro_mcu_wait_for_sleep(dev);
+}
+
+/*
+ * Create the MCU channel
+ *
+ * After the channel has been created, the picture size, format, colorspace
+ * and framerate are fixed. Also the codec, profile, bitrate, etc. cannot be
+ * changed anymore.
+ *
+ * The channel can be created only once. The MCU will accept source buffers
+ * and stream buffers only after a channel has been created.
+ */
+static int allegro_create_channel(struct allegro_channel *channel)
+{
+	struct allegro_dev *dev = channel->dev;
+	unsigned long timeout;
+	int err;
+	enum v4l2_mpeg_video_h264_level min_level;
+
+	if (channel->created) {
+		v4l2_warn(&dev->v4l2_dev,
+			  "channel already has been created\n");
+		return 0;
+	}
+
+	channel->user_id = allegro_next_user_id(dev);
+	if (channel->user_id < 0) {
+		v4l2_err(&dev->v4l2_dev,
+			 "no free channels available\n");
+		return -EBUSY;
+	}
+	set_bit(channel->user_id, &dev->channel_user_ids);
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "user %d: creating channel (%4.4s, %dx%d@%d) \n",
+		 channel->user_id,
+		 (char *)&channel->codec, channel->width, channel->height, 25);
+
+	min_level = select_minimum_h264_level(channel->width, channel->height);
+	if (channel->level < min_level) {
+		v4l2_warn(&dev->v4l2_dev,
+			  "user %d: selected Level %s too low: increasing to Level %s\n",
+			  channel->user_id,
+			  v4l2_ctrl_get_menu(V4L2_CID_MPEG_VIDEO_H264_LEVEL)[channel->level],
+			  v4l2_ctrl_get_menu(V4L2_CID_MPEG_VIDEO_H264_LEVEL)[min_level]);
+		channel->level = min_level;
+	}
+
+	reinit_completion(&channel->completion);
+	allegro_mcu_send_create_channel(dev, channel);
+	timeout = wait_for_completion_timeout(&channel->completion,
+					      msecs_to_jiffies(5000));
+	if (timeout == 0) {
+		err = -ETIMEDOUT;
+		goto err;
+	}
+	if (!channel->created) {
+		/* FIXME Return a proper error code */
+		err = -1;
+		goto err;
+	}
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "channel %d: accepting buffers\n",
+		 channel->mcu_channel_id);
+
+	return 0;
+
+err:
+	clear_bit(channel->user_id, &dev->channel_user_ids);
+	channel->user_id = -1;
+	return err;
+}
+
+static void allegro_destroy_channel(struct allegro_channel *channel)
+{
+	struct allegro_dev *dev = channel->dev;
+	unsigned long timeout;
+
+	if (!channel->created) {
+		v4l2_warn(&dev->v4l2_dev,
+			  "cannot destroy channel: has not been created\n");
+		return;
+	}
+
+	reinit_completion(&channel->completion);
+	allegro_mcu_send_destroy_channel(dev, channel);
+	timeout = wait_for_completion_timeout(&channel->completion,
+					      msecs_to_jiffies(5000));
+	if (timeout == 0)
+		v4l2_warn(&dev->v4l2_dev,
+			  "timeout while destroying channel %d\n",
+			  channel->mcu_channel_id);
+
+	channel->mcu_channel_id = -1;
+	channel->created = false;
+	clear_bit(channel->user_id, &dev->channel_user_ids);
+	channel->user_id = -1;
+
+	destroy_intermediate_buffers(channel);
+	destroy_reference_buffers(channel);
+}
+
+static void allegro_set_default_params(struct allegro_channel *channel)
+{
+	channel->width = ALLEGRO_WIDTH_DEFAULT;
+	channel->height = ALLEGRO_HEIGHT_DEFAULT;
+	channel->stride = round_up(channel->width, 32);
+
+	channel->colorspace = V4L2_COLORSPACE_REC709;
+	channel->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
+	channel->quantization = V4L2_QUANTIZATION_DEFAULT;
+	channel->xfer_func = V4L2_XFER_FUNC_DEFAULT;
+
+	channel->pixelformat = V4L2_PIX_FMT_NV12;
+	channel->sizeimage_raw = channel->stride * channel->height * 3 / 2;
+
+	channel->codec = V4L2_PIX_FMT_H264;
+	channel->profile = V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE;
+	channel->level =
+		select_minimum_h264_level(channel->width, channel->height);
+	channel->sizeimage_encoded =
+		estimate_stream_size(channel->width, channel->height);
+
+	channel->bitrate_mode = V4L2_MPEG_VIDEO_BITRATE_MODE_CBR;
+	channel->bitrate = maximum_bitrate(channel->level);
+	channel->bitrate_peak = maximum_bitrate(channel->level);
+	channel->cpb_size = maximum_cpb_size(channel->level);
+	channel->gop_size = ALLEGRO_GOP_SIZE_DEFAULT;
+}
+
+static int allegro_queue_setup(struct vb2_queue *vq,
+			       unsigned int *nbuffers, unsigned int *nplanes,
+			       unsigned int sizes[],
+			       struct device *alloc_devs[])
+{
+	struct allegro_channel *channel = vb2_get_drv_priv(vq);
+	struct allegro_dev *dev = channel->dev;
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		 "%s: queue setup[%s]: nplanes = %d\n",
+		 vq->type == V4L2_BUF_TYPE_VIDEO_OUTPUT ? "output" : "capture",
+		 *nplanes == 0 ? "REQBUFS" : "CREATE_BUFS", *nplanes);
+
+	if (*nplanes != 0) {
+		if (vq->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+			if (*nplanes != 1 ||
+			    sizes[0] < channel->sizeimage_encoded)
+				return -EINVAL;
+
+		} else {
+			if (*nplanes != 1 || sizes[0] < channel->sizeimage_raw)
+				return -EINVAL;
+		}
+		return 0;
+	}
+
+	if (vq->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+		*nplanes = 1;
+		sizes[0] = channel->sizeimage_encoded;
+	} else {
+		*nplanes = 1;
+		sizes[0] = channel->sizeimage_raw;
+	}
+
+	return 0;
+}
+
+static void allegro_buf_queue(struct vb2_buffer *vb)
+{
+	struct allegro_channel *channel = vb2_get_drv_priv(vb->vb2_queue);
+	struct allegro_dev *dev = channel->dev;
+	struct vb2_queue *vq = vb->vb2_queue;
+	struct allegro_buffer al_buf;
+
+	if (vq->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+		al_buf.paddr = vb2_dma_contig_plane_dma_addr(vb, 0);
+		al_buf.size = vb2_plane_size(vb, 0);
+
+		if (poison_capture_buffers)
+			memset(vb2_plane_vaddr(vb, 0), 0x1a, vb2_plane_size(vb, 0));
+
+		v4l2_dbg(1, debug, &dev->v4l2_dev,
+			 "channel %d: queuing stream buffer: paddr: 0x%08llx, %ld bytes\n",
+			 channel->mcu_channel_id, al_buf.paddr, al_buf.size);
+		allegro_mcu_send_put_stream_buffer(dev, channel, al_buf);
+	} else {
+		v4l2_dbg(1, debug, &dev->v4l2_dev,
+			 "channel %d: queuing source buffer\n",
+			 channel->mcu_channel_id);
+	}
+
+	v4l2_m2m_buf_queue(channel->fh.m2m_ctx, to_vb2_v4l2_buffer(vb));
+}
+
+static int allegro_start_streaming(struct vb2_queue *q, unsigned int count)
+{
+	struct allegro_channel *channel = vb2_get_drv_priv(q);
+	struct allegro_dev *dev = channel->dev;
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		 "%s: start streaming\n",
+		 q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT ? "output" : "capture");
+
+	return 0;
+}
+
+static void allegro_stop_streaming(struct vb2_queue *q)
+{
+	struct allegro_channel *channel = vb2_get_drv_priv(q);
+	struct allegro_dev *dev = channel->dev;
+	struct vb2_v4l2_buffer *buffer;
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		 "%s: stop streaming\n",
+		 q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT ? "output" : "capture");
+
+	if (q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT) {
+		while ((buffer = v4l2_m2m_src_buf_remove(channel->fh.m2m_ctx)))
+			v4l2_m2m_buf_done(buffer, VB2_BUF_STATE_ERROR);
+	} else if (q->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+		/*
+		 * FIXME The channel is created during queue_setup().
+		 * Therefore, destroying it in stop_streaming might result in
+		 * a start_streaming() without a channel, which is really bad.
+		 */
+		allegro_destroy_channel(channel);
+		while ((buffer = v4l2_m2m_dst_buf_remove(channel->fh.m2m_ctx)))
+			v4l2_m2m_buf_done(buffer, VB2_BUF_STATE_ERROR);
+	}
+}
+
+static const struct vb2_ops allegro_queue_ops = {
+	.queue_setup = allegro_queue_setup,
+	.buf_queue = allegro_buf_queue,
+	.start_streaming = allegro_start_streaming,
+	.stop_streaming = allegro_stop_streaming,
+};
+
+static int allegro_queue_init(void *priv,
+			      struct vb2_queue *src_vq,
+			      struct vb2_queue *dst_vq)
+{
+	int err;
+	struct allegro_channel *channel = priv;
+
+	src_vq->dev = &channel->dev->plat_dev->dev;
+	src_vq->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+	src_vq->io_modes = VB2_DMABUF | VB2_MMAP;
+	src_vq->mem_ops = &vb2_dma_contig_memops;
+	src_vq->drv_priv = channel;
+	src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
+	src_vq->ops = &allegro_queue_ops;
+	src_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
+	err = vb2_queue_init(src_vq);
+	if (err)
+		return err;
+
+	dst_vq->dev = &channel->dev->plat_dev->dev;
+	dst_vq->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	dst_vq->io_modes = VB2_DMABUF | VB2_MMAP;
+	dst_vq->mem_ops = &vb2_dma_contig_memops;
+	dst_vq->drv_priv = channel;
+	dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
+	dst_vq->ops = &allegro_queue_ops;
+	dst_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
+	err = vb2_queue_init(dst_vq);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int allegro_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct allegro_channel *channel = container_of(ctrl->handler,
+						       struct allegro_channel,
+						       ctrl_handler);
+	struct allegro_dev *dev = channel->dev;
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "s_ctrl: id = %d, val = %d\n", ctrl->id, ctrl->val);
+
+	switch (ctrl->id) {
+	case V4L2_CID_MPEG_VIDEO_H264_LEVEL:
+		channel->level = ctrl->val;
+		break;
+	case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
+		channel->bitrate_mode = ctrl->val;
+		break;
+	case V4L2_CID_MPEG_VIDEO_BITRATE:
+		channel->bitrate = ctrl->val;
+		break;
+	case V4L2_CID_MPEG_VIDEO_BITRATE_PEAK:
+		channel->bitrate_peak = ctrl->val;
+		break;
+	case V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE:
+		channel->cpb_size = ctrl->val;
+		break;
+	case V4L2_CID_MPEG_VIDEO_GOP_SIZE:
+		channel->gop_size = ctrl->val;
+		break;
+	}
+
+	return 0;
+}
+
+static const struct v4l2_ctrl_ops allegro_ctrl_ops = {
+	.s_ctrl = allegro_s_ctrl,
+};
+
+static int allegro_open(struct file *file)
+{
+	struct video_device *vdev = video_devdata(file);
+	struct allegro_dev *dev = video_get_drvdata(vdev);
+	struct allegro_channel *channel = NULL;
+	u64 mask;
+
+	channel = kzalloc(sizeof(*channel), GFP_KERNEL);
+	if (!channel)
+		return -ENOMEM;
+
+	v4l2_fh_init(&channel->fh, vdev);
+	file->private_data = &channel->fh;
+	v4l2_fh_add(&channel->fh);
+
+	init_completion(&channel->completion);
+
+	channel->dev = dev;
+
+	allegro_set_default_params(channel);
+
+	v4l2_ctrl_handler_init(&channel->ctrl_handler, 0);
+	v4l2_ctrl_new_std_menu(&channel->ctrl_handler, &allegro_ctrl_ops,
+			       V4L2_CID_MPEG_VIDEO_H264_PROFILE,
+			       V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE, 0x0,
+			       V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE);
+	mask = 1 << V4L2_MPEG_VIDEO_H264_LEVEL_1B;
+	v4l2_ctrl_new_std_menu(&channel->ctrl_handler, &allegro_ctrl_ops,
+			       V4L2_CID_MPEG_VIDEO_H264_LEVEL,
+			       V4L2_MPEG_VIDEO_H264_LEVEL_5_1, mask,
+			       V4L2_MPEG_VIDEO_H264_LEVEL_5_1);
+	v4l2_ctrl_new_std_menu(&channel->ctrl_handler, &allegro_ctrl_ops,
+			       V4L2_CID_MPEG_VIDEO_BITRATE_MODE,
+			       V4L2_MPEG_VIDEO_BITRATE_MODE_CBR, 0,
+			       channel->bitrate_mode);
+	v4l2_ctrl_new_std(&channel->ctrl_handler, &allegro_ctrl_ops,
+			  V4L2_CID_MPEG_VIDEO_BITRATE,
+			  0, maximum_bitrate(V4L2_MPEG_VIDEO_H264_LEVEL_5_1),
+			  1, channel->bitrate);
+	v4l2_ctrl_new_std(&channel->ctrl_handler, &allegro_ctrl_ops,
+			  V4L2_CID_MPEG_VIDEO_BITRATE_PEAK,
+			  0, maximum_bitrate(V4L2_MPEG_VIDEO_H264_LEVEL_5_1),
+			  1, channel->bitrate_peak);
+	v4l2_ctrl_new_std(&channel->ctrl_handler, &allegro_ctrl_ops,
+			  V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE,
+			  0, maximum_cpb_size(V4L2_MPEG_VIDEO_H264_LEVEL_5_1),
+			  1, channel->cpb_size);
+	v4l2_ctrl_new_std(&channel->ctrl_handler, &allegro_ctrl_ops,
+			  V4L2_CID_MPEG_VIDEO_GOP_SIZE,
+			  0, ALLEGRO_GOP_SIZE_MAX,
+			  1, channel->gop_size);
+	channel->fh.ctrl_handler = &channel->ctrl_handler;
+
+	channel->mcu_channel_id = -1;
+	channel->user_id = -1;
+	channel->created = false;
+	channel->stop = false;
+
+	INIT_LIST_HEAD(&channel->buffers_reference);
+	INIT_LIST_HEAD(&channel->buffers_intermediate);
+
+	channel->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, channel,
+						allegro_queue_init);
+
+	list_add(&channel->list, &dev->channels);
+
+	return 0;
+}
+
+static int allegro_release(struct file *file)
+{
+	struct allegro_channel *channel = fh_to_channel(file->private_data);
+
+	list_del(&channel->list);
+
+	v4l2_m2m_ctx_release(channel->fh.m2m_ctx);
+
+	v4l2_ctrl_handler_free(&channel->ctrl_handler);
+
+	v4l2_fh_del(&channel->fh);
+	v4l2_fh_exit(&channel->fh);
+
+	kfree(channel);
+
+	return 0;
+}
+
+static int allegro_querycap(struct file *file, void *fh,
+			    struct v4l2_capability *cap)
+{
+	struct video_device *vdev = video_devdata(file);
+	struct allegro_dev *dev = video_get_drvdata(vdev);
+
+	strscpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
+	strscpy(cap->card, "Allegro DVT Video Encoder", sizeof(cap->card));
+	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
+		 dev_name(&dev->plat_dev->dev));
+
+	cap->device_caps = V4L2_CAP_VIDEO_M2M | V4L2_CAP_STREAMING;
+	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
+
+	return 0;
+}
+
+static int allegro_enum_fmt_vid(struct file *file, void *fh,
+				struct v4l2_fmtdesc *f)
+{
+	unsigned int num_formats = 1;
+
+	switch (f->type) {
+	case V4L2_BUF_TYPE_VIDEO_OUTPUT:
+		f->pixelformat = V4L2_PIX_FMT_NV12;
+		break;
+	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
+		f->pixelformat = V4L2_PIX_FMT_H264;
+		break;
+	default:
+		return -EINVAL;
+	}
+	if (f->index >= num_formats)
+		return -EINVAL;
+	return 0;
+}
+
+static int allegro_g_fmt_vid_cap(struct file *file, void *fh,
+				 struct v4l2_format *f)
+{
+	struct allegro_channel *channel = fh_to_channel(fh);
+
+	if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+		return -EINVAL;
+
+	f->fmt.pix.field = V4L2_FIELD_NONE;
+	f->fmt.pix.width = channel->width;
+	f->fmt.pix.height = channel->height;
+
+	f->fmt.pix.colorspace = channel->colorspace;
+	f->fmt.pix.ycbcr_enc = channel->ycbcr_enc;
+	f->fmt.pix.quantization = channel->quantization;
+	f->fmt.pix.xfer_func = channel->xfer_func;
+
+	f->fmt.pix.pixelformat = channel->codec;
+	f->fmt.pix.flags = V4L2_FMT_FLAG_COMPRESSED;
+	f->fmt.pix.bytesperline = channel->width;
+	f->fmt.pix.sizeimage = channel->sizeimage_encoded;
+
+	return 0;
+}
+
+static int allegro_try_fmt_vid_cap(struct file *file, void *fh,
+				   struct v4l2_format *f)
+{
+	f->fmt.pix.field = V4L2_FIELD_NONE;
+
+	f->fmt.pix.width = clamp_t(__u32, f->fmt.pix.width,
+				   ALLEGRO_WIDTH_MIN, ALLEGRO_WIDTH_MAX);
+	f->fmt.pix.height = clamp_t(__u32, f->fmt.pix.height,
+				    ALLEGRO_HEIGHT_MIN, ALLEGRO_HEIGHT_MAX);
+
+	f->fmt.pix.pixelformat = V4L2_PIX_FMT_H264;
+	f->fmt.pix.flags = V4L2_FMT_FLAG_COMPRESSED;
+	f->fmt.pix.bytesperline = f->fmt.pix.width;
+	f->fmt.pix.sizeimage =
+		estimate_stream_size(f->fmt.pix.width, f->fmt.pix.height);
+
+	return 0;
+}
+
+static int allegro_g_fmt_vid_out(struct file *file, void *fh,
+				 struct v4l2_format *f)
+{
+	struct allegro_channel *channel = fh_to_channel(fh);
+
+	if (f->type != V4L2_BUF_TYPE_VIDEO_OUTPUT)
+		return -EINVAL;
+
+	f->fmt.pix.field = V4L2_FIELD_NONE;
+
+	f->fmt.pix.width = channel->width;
+	f->fmt.pix.height = channel->height;
+
+	f->fmt.pix.colorspace = channel->colorspace;
+	f->fmt.pix.ycbcr_enc = channel->ycbcr_enc;
+	f->fmt.pix.quantization = channel->quantization;
+	f->fmt.pix.xfer_func = channel->xfer_func;
+
+	f->fmt.pix.pixelformat = channel->pixelformat;
+	f->fmt.pix.bytesperline = channel->stride;
+	f->fmt.pix.sizeimage = channel->sizeimage_raw;
+
+	return 0;
+}
+
+static int allegro_try_fmt_vid_out(struct file *file, void *fh,
+				   struct v4l2_format *f)
+{
+	f->fmt.pix.field = V4L2_FIELD_NONE;
+
+	f->fmt.pix.width = clamp_t(__u32, f->fmt.pix.width,
+				   ALLEGRO_WIDTH_MIN, ALLEGRO_WIDTH_MAX);
+	f->fmt.pix.height = clamp_t(__u32, f->fmt.pix.height,
+				    ALLEGRO_HEIGHT_MIN, ALLEGRO_HEIGHT_MAX);
+
+	f->fmt.pix.pixelformat = V4L2_PIX_FMT_NV12;
+	f->fmt.pix.bytesperline = round_up(f->fmt.pix.width, 32);
+	f->fmt.pix.sizeimage =
+		f->fmt.pix.bytesperline * f->fmt.pix.height * 3 / 2;
+
+	return 0;
+}
+
+static int allegro_s_fmt_vid_out(struct file *file, void *fh,
+				 struct v4l2_format *f)
+{
+	struct allegro_channel *channel = fh_to_channel(fh);
+	int err;
+
+	err = allegro_try_fmt_vid_out(file, fh, f);
+	if (err)
+		return err;
+
+	channel->width = f->fmt.pix.width;
+	channel->height = f->fmt.pix.height;
+	channel->stride = f->fmt.pix.bytesperline;
+	channel->sizeimage_raw = f->fmt.pix.sizeimage;
+
+	channel->colorspace = f->fmt.pix.colorspace;
+	channel->ycbcr_enc = f->fmt.pix.ycbcr_enc;
+	channel->quantization = f->fmt.pix.quantization;
+	channel->xfer_func = f->fmt.pix.xfer_func;
+
+	channel->level =
+		select_minimum_h264_level(channel->width, channel->height);
+	channel->sizeimage_encoded =
+		estimate_stream_size(channel->width, channel->height);
+
+	return 0;
+}
+
+static int allegro_try_encoder_cmd(struct file *file, void *fh,
+				   struct v4l2_encoder_cmd *cmd)
+{
+	if (cmd->cmd != V4L2_ENC_CMD_STOP)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int allegro_encoder_cmd(struct file *file, void *fh,
+			       struct v4l2_encoder_cmd *cmd)
+{
+	struct allegro_channel *channel = fh_to_channel(fh);
+	struct allegro_dev *dev = channel->dev;
+	int err;
+
+	err = allegro_try_encoder_cmd(file, fh, cmd);
+	if (err)
+		return err;
+
+	v4l2_dbg(2, debug, &dev->v4l2_dev,
+		 "channel %d: stop encoder\n", channel->mcu_channel_id);
+
+	channel->stop = true;
+
+	return 0;
+}
+
+static int allegro_ioctl_streamon(struct file *file, void *priv,
+				  enum v4l2_buf_type type)
+{
+	struct v4l2_fh *fh = file->private_data;
+	struct allegro_channel *channel = fh_to_channel(fh);
+	struct allegro_dev *dev = channel->dev;
+	int err;
+
+	/*
+	 * The channel should be created as late as possible, but has to be
+	 * created before we queue stream buffers on capture. Therefore,
+	 * start_streaming() is already too late.
+	 */
+	if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+		err = allegro_create_channel(channel);
+		if (err) {
+			v4l2_err(&dev->v4l2_dev, "failed to create channel");
+			return err;
+		}
+	}
+
+	return v4l2_m2m_streamon(file, fh->m2m_ctx, type);
+}
+
+static const struct v4l2_ioctl_ops allegro_ioctl_ops = {
+	.vidioc_querycap = allegro_querycap,
+	.vidioc_enum_fmt_vid_cap = allegro_enum_fmt_vid,
+	.vidioc_enum_fmt_vid_out = allegro_enum_fmt_vid,
+	.vidioc_g_fmt_vid_cap = allegro_g_fmt_vid_cap,
+	.vidioc_try_fmt_vid_cap = allegro_try_fmt_vid_cap,
+	.vidioc_s_fmt_vid_cap = allegro_try_fmt_vid_cap,
+	.vidioc_g_fmt_vid_out = allegro_g_fmt_vid_out,
+	.vidioc_try_fmt_vid_out = allegro_try_fmt_vid_out,
+	.vidioc_s_fmt_vid_out = allegro_s_fmt_vid_out,
+
+	.vidioc_create_bufs = v4l2_m2m_ioctl_create_bufs,
+	.vidioc_reqbufs = v4l2_m2m_ioctl_reqbufs,
+
+	.vidioc_expbuf = v4l2_m2m_ioctl_expbuf,
+	.vidioc_querybuf = v4l2_m2m_ioctl_querybuf,
+	.vidioc_qbuf = v4l2_m2m_ioctl_qbuf,
+	.vidioc_dqbuf = v4l2_m2m_ioctl_dqbuf,
+
+	.vidioc_streamon = allegro_ioctl_streamon,
+	.vidioc_streamoff = v4l2_m2m_ioctl_streamoff,
+
+	.vidioc_try_encoder_cmd = allegro_try_encoder_cmd,
+	.vidioc_encoder_cmd = allegro_encoder_cmd,
+
+	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
+	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
+};
+
+static const struct v4l2_file_operations allegro_fops = {
+	.owner = THIS_MODULE,
+	.open = allegro_open,
+	.release = allegro_release,
+	.poll = v4l2_m2m_fop_poll,
+	.unlocked_ioctl = video_ioctl2,
+	.mmap = v4l2_m2m_fop_mmap,
+};
+
+static int allegro_register_device(struct allegro_dev *dev)
+{
+	struct video_device *video_dev = &dev->video_dev;
+
+	strscpy(video_dev->name, "allegro", sizeof(video_dev->name));
+	video_dev->fops = &allegro_fops;
+	video_dev->ioctl_ops = &allegro_ioctl_ops;
+	video_dev->release = video_device_release_empty;
+	video_dev->lock = &dev->lock;
+	video_dev->v4l2_dev = &dev->v4l2_dev;
+	video_dev->vfl_dir = VFL_DIR_M2M;
+	video_set_drvdata(video_dev, dev);
+
+	v4l2_disable_ioctl(video_dev, VIDIOC_CROPCAP);
+	v4l2_disable_ioctl(video_dev, VIDIOC_G_CROP);
+	v4l2_disable_ioctl(video_dev, VIDIOC_S_CROP);
+
+	return video_register_device(video_dev, VFL_TYPE_GRABBER, 0);
+}
+
+static void allegro_device_run(void *priv)
+{
+	struct allegro_channel *channel = priv;
+	struct allegro_dev *dev = channel->dev;
+	struct vb2_v4l2_buffer *src_buf;
+	dma_addr_t src_y;
+	dma_addr_t src_uv;
+
+	src_buf = v4l2_m2m_next_src_buf(channel->fh.m2m_ctx);
+
+	src_y = vb2_dma_contig_plane_dma_addr(&src_buf->vb2_buf, 0);
+	src_uv = src_y + (channel->stride * channel->height);
+
+	allegro_mcu_send_encode_frame(dev, channel, src_y, src_uv);
+}
+
+static int allegro_job_ready(void *priv)
+{
+	struct allegro_channel *channel = priv;
+	struct allegro_dev *dev = channel->dev;
+
+	if (v4l2_m2m_num_src_bufs_ready(channel->fh.m2m_ctx) == 0) {
+		v4l2_dbg(2, debug, &dev->v4l2_dev,
+			 "channel %d: no frame buffers\n",
+			 channel->mcu_channel_id);
+		return false;
+	}
+
+	if (v4l2_m2m_num_dst_bufs_ready(channel->fh.m2m_ctx) == 0) {
+		v4l2_dbg(2, debug, &dev->v4l2_dev,
+			 "channel %d: no stream buffers\n",
+			 channel->mcu_channel_id);
+		return false;
+	}
+
+	return true;
+}
+
+static void allegro_job_abort(void *priv)
+{
+	struct allegro_channel *channel = priv;
+	struct allegro_dev *dev = channel->dev;
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev, "%s\n", __func__);
+}
+
+static const struct v4l2_m2m_ops allegro_m2m_ops = {
+	.device_run = allegro_device_run,
+	.job_ready = allegro_job_ready,
+	.job_abort = allegro_job_abort,
+};
+
+static void allegro_fw_callback(const struct firmware *fw, void *context)
+{
+	struct allegro_dev *dev = context;
+	const char *fw_codec_name = "al5e.fw";
+	const struct firmware *fw_codec;
+	int err;
+	const struct fw_info *info;
+
+	info = allegro_get_firmware_info(dev, fw);
+	if (!info) {
+		v4l2_err(&dev->v4l2_dev,
+			 "mcu firmware %s is not supported\n", fw_codec_name);
+		release_firmware(fw);
+		return;
+	}
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "detected mcu firmware version '%s'\n", info->version);
+
+	allegro_mcu_reset(dev);
+
+	allegro_copy_firmware(dev, fw->data, fw->size);
+	release_firmware(fw);
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "requesting firmware '%s'\n", fw_codec_name);
+	err = request_firmware(&fw_codec, fw_codec_name, &dev->plat_dev->dev);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "cannot find codec firmware '%s'\n", fw_codec_name);
+		release_firmware(fw_codec);
+		return;
+	}
+	allegro_copy_fw_codec(dev, fw_codec->data, fw_codec->size);
+	release_firmware(fw_codec);
+
+	allegro_mbox_init(dev, &dev->mbox_command, MAILBOX_CMD, MAILBOX_SIZE);
+	allegro_mbox_init(dev, &dev->mbox_status, MAILBOX_STATUS, MAILBOX_SIZE);
+
+	allegro_mcu_enable_interrupts(dev);
+	allegro_mcu_start(dev);
+
+	/* The MCU sends an INIT message once it has started. */
+	err = allegro_mcu_wait_for_init_timeout(dev, 5000);
+	if (err == -ETIMEDOUT) {
+		v4l2_err(&dev->v4l2_dev,
+			 "no INIT from MCU after start\n");
+		return;
+	}
+
+	err =
+	    allegro_alloc_buffer(dev, &dev->suballocator,
+				 MCU_SUBALLOCATOR_SIZE);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "failed to allocate %u bytes for suballocator\n",
+			 MCU_SUBALLOCATOR_SIZE);
+		return;
+	}
+
+	allegro_mcu_send_init(dev, dev->suballocator.paddr,
+			      dev->suballocator.size);
+	err = allegro_mcu_wait_for_init_timeout(dev, 5000);
+	if (err == -ETIMEDOUT) {
+		v4l2_err(&dev->v4l2_dev,
+			 "failed to configure sub-allocator\n");
+		return;
+	}
+
+	dev->m2m_dev = v4l2_m2m_init(&allegro_m2m_ops);
+	if (IS_ERR(dev->m2m_dev)) {
+		v4l2_err(&dev->v4l2_dev, "failed to init mem2mem device\n");
+		return;
+	}
+
+	err = allegro_register_device(dev);
+	if (err) {
+		v4l2_err(&dev->v4l2_dev,
+			 "Failed to register devices\n");
+		return;
+	}
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "allegro codec registered as /dev/video%d\n",
+		 dev->video_dev.num);
+}
+
+static int allegro_firmware_request(struct allegro_dev *dev)
+{
+	const char *fw = "al5e_b.fw";
+
+	v4l2_dbg(1, debug, &dev->v4l2_dev,
+		 "requesting firmware '%s'\n", fw);
+	return request_firmware_nowait(THIS_MODULE, true, fw,
+				       &dev->plat_dev->dev, GFP_KERNEL, dev,
+				       allegro_fw_callback);
+}
+
+static int allegro_probe(struct platform_device *pdev)
+{
+	struct allegro_dev *dev;
+	struct resource *res, *sram_res;
+	int ret;
+	int irq;
+	void __iomem *regs, *sram_regs;
+
+	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+	dev->plat_dev = pdev;
+	init_completion(&dev->init_complete);
+	INIT_LIST_HEAD(&dev->channels);
+
+	mutex_init(&dev->lock);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
+	if (!res) {
+		dev_err(&pdev->dev,
+			"regs resource missing from device tree\n");
+		return -EINVAL;
+	}
+	regs = devm_ioremap_nocache(&pdev->dev, res->start, resource_size(res));
+	if (IS_ERR(regs)) {
+		dev_err(&pdev->dev, "failed to map registers\n");
+		return PTR_ERR(regs);
+	}
+	dev->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
+					    &allegro_regmap_config);
+	if (IS_ERR(dev->regmap)) {
+		dev_err(&pdev->dev, "failed to init regmap\n");
+		return PTR_ERR(dev->regmap);
+	}
+
+	sram_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
+	if (!sram_res) {
+		dev_err(&pdev->dev,
+			"sram resource missing from device tree\n");
+		return -EINVAL;
+	}
+	sram_regs = devm_ioremap_nocache(&pdev->dev,
+					 sram_res->start,
+					 resource_size(sram_res));
+	if (IS_ERR(sram_regs)) {
+		dev_err(&pdev->dev, "failed to map sram\n");
+		return PTR_ERR(sram_regs);
+	}
+	dev->sram = devm_regmap_init_mmio(&pdev->dev, sram_regs,
+					  &allegro_sram_config);
+	if (IS_ERR(dev->sram)) {
+		dev_err(&pdev->dev, "failed to init sram\n");
+		return PTR_ERR(dev->sram);
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get irq resource\n");
+		return irq;
+	}
+	ret = devm_request_threaded_irq(&pdev->dev, irq,
+					allegro_hardirq,
+					allegro_irq_thread,
+					IRQF_SHARED, dev_name(&pdev->dev), dev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to request irq: %d\n", ret);
+		return ret;
+	}
+
+	ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, dev);
+
+	ret = allegro_firmware_request(dev);
+	if (ret < 0) {
+		v4l2_err(&dev->v4l2_dev,
+			 "failed to request firmware: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int allegro_remove(struct platform_device *pdev)
+{
+	struct allegro_dev *dev = platform_get_drvdata(pdev);
+
+	allegro_free_buffer(dev, &dev->firmware);
+	allegro_free_buffer(dev, &dev->suballocator);
+
+	video_unregister_device(&dev->video_dev);
+
+	v4l2_m2m_release(dev->m2m_dev);
+
+	v4l2_device_unregister(&dev->v4l2_dev);
+
+	return 0;
+}
+
+static const struct of_device_id allegro_dt_ids[] = {
+	{ .compatible = "allegro,al5e-1.1" },
+	{ /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, allegro_dt_ids);
+
+static struct platform_driver allegro_driver = {
+	.probe = allegro_probe,
+	.remove = allegro_remove,
+	.driver = {
+		.name = "allegro",
+		.of_match_table = of_match_ptr(allegro_dt_ids),
+	},
+};
+
+module_platform_driver(allegro_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Michael Tretter <kernel@pengutronix.de>");
+MODULE_DESCRIPTION("Allegro DVT encoder and decoder driver");
