/*
 * Copyright 2018 Synaptics
 * Copyright 2018 Dell Inc.
 * All rights reserved.
 *
 * This software and associated documentation (if any) is furnished
 * under a license and may only be used or copied in accordance
 * with the terms of the license.
 *
 * This file is provided under a dual MIT/LGPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 * Dell Chooses the MIT license part of Dual MIT/LGPLv2 license agreement.
 *
 * SPDX-License-Identifier: LGPL-2.1-or-later OR MIT
 */

#include "config.h"

#include <string.h>

#include "fu-dell-dock-common.h"
#include "fu-dell-dock-struct.h"

/*
 * NOTE: DO NOT ALLOW ANY MORE MAGIC CONSTANTS IN THIS FILE
 * nocheck:magic-defines=38
 * nocheck:magic-inlines=600
 */

#define I2C_MST_ADDRESS 0x72

/* Panamera MST registers */
#define PANAMERA_MST_RC_TRIGGER_ADDR	     0x2000fc
#define PANAMERA_MST_CORE_MCU_BOOTLOADER_STS 0x20010c
#define PANAMERA_MST_RC_COMMAND_ADDR	     0x200110
#define PANAMERA_MST_RC_OFFSET_ADDR	     0x200114
#define PANAMERA_MST_RC_LENGTH_ADDR	     0x200118
#define PANAMERA_MST_RC_DATA_ADDR	     0x200120
#define PANAMERA_MST_CORE_MCU_FW_VERSION     0x200160
#define PANAMERA_MST_REG_QUAD_DISABLE	     0x200fc0
#define PANAMERA_MST_REG_HDCP22_DISABLE	     0x200f90

/* Cayenne MST registers */
#define CAYENNE_MST_RC_TRIGGER_ADDR	    0x2020021C
#define CAYENNE_MST_CORE_MCU_BOOTLOADER_STS 0x2020022C
#define CAYENNE_MST_RC_COMMAND_ADDR	    0x20200280
#define CAYENNE_MST_RC_OFFSET_ADDR	    0x20200284
#define CAYENNE_MST_RC_LENGTH_ADDR	    0x20200288
#define CAYENNE_MST_RC_DATA_ADDR	    0x20200290

/* Arguments related to flashing */
#define FLASH_SECTOR_ERASE_4K  0x1000
#define FLASH_SECTOR_ERASE_32K 0x2000
#define FLASH_SECTOR_ERASE_64K 0x3000
#define EEPROM_TAG_OFFSET      0x1fff0
#define EEPROM_BANK_OFFSET     0x20000
#define EEPROM_ESM_OFFSET      0x40000

/* Flash offsets */
#define MST_BOARDID_OFFSET 0x10e

/* Remote control offsets */
#define MST_CHIPID_OFFSET 0x1500

/* magic triggers */
#define MST_TRIGGER_WRITE  0xf2
#define MST_TRIGGER_REBOOT 0xf5

/* IDs used in DELL_DOCK */
#define EXPECTED_CHIPID 0x5331

/* firmware file offsets */
#define MST_BLOB_VERSION_OFFSET 0x06F0

typedef struct {
	guint start;
	guint length;
	guint checksum_cmd;
} FuDellDockMstBankAttributes;

const FuDellDockMstBankAttributes bank0_attributes = {
    .start = 0,
    .length = EEPROM_BANK_OFFSET,
    .checksum_cmd = FU_DELL_DOCK_MST_CMD_CHECKSUM,
};

const FuDellDockMstBankAttributes bank1_attributes = {
    .start = EEPROM_BANK_OFFSET,
    .length = EEPROM_BANK_OFFSET,
    .checksum_cmd = FU_DELL_DOCK_MST_CMD_CHECKSUM,
};

const FuDellDockMstBankAttributes esm_attributes = {
    .start = EEPROM_ESM_OFFSET,
    .length = 0x3ffff,
    .checksum_cmd = FU_DELL_DOCK_MST_CMD_CHECKSUM,
};

const FuDellDockMstBankAttributes cayenne_attributes = {
    .start = 0,
    .length = 0x50000,
    .checksum_cmd = FU_DELL_DOCK_MST_CMD_CRC16_CHECKSUM,
};

FuHIDI2CParameters mst_base_settings = {
    .i2ctargetaddr = I2C_MST_ADDRESS,
    .regaddrlen = 0,
    .i2cspeed = FU_DELL_DOCK_I2C_SPEED_400K,
};

struct _FuDellDockMst {
	FuDevice parent_instance;
	guint8 unlock_target;
	guint64 blob_major_offset;
	guint64 blob_minor_offset;
	guint64 blob_build_offset;
	guint32 mst_rc_trigger_addr;
	guint32 mst_rc_command_addr;
	guint32 mst_rc_data_addr;
	guint32 mst_core_mcu_bootloader_addr;
	guint8 dock_type;
	FuDellDockMstType mst_type;
};

G_DEFINE_TYPE(FuDellDockMst, fu_dell_dock_mst, FU_TYPE_DEVICE)

/**
 * fu_dell_dock_mst_get_bank_attribs:
 * @bank: the FuDellDockMstBank
 * @out (out): the FuDellDockMstBankAttributes attribute that matches
 * @error: (nullable): optional return location for an error
 *
 * Returns a structure that corresponds to the attributes for a bank
 *
 * Returns: %TRUE for success
 **/
static gboolean
fu_dell_dock_mst_get_bank_attribs(FuDellDockMstBank bank,
				  const FuDellDockMstBankAttributes **out,
				  GError **error)
{
	switch (bank) {
	case FU_DELL_DOCK_MST_BANK_0:
		*out = &bank0_attributes;
		break;
	case FU_DELL_DOCK_MST_BANK_1:
		*out = &bank1_attributes;
		break;
	case FU_DELL_DOCK_MST_BANK_ESM:
		*out = &esm_attributes;
		break;
	case FU_DELL_DOCK_MST_BANK_CAYENNE:
		*out = &cayenne_attributes;
		break;
	default:
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_INTERNAL,
			    "invalid bank specified %u",
			    bank);
		return FALSE;
	}
	return TRUE;
}

static gboolean
fu_dell_dock_mst_rc_command(FuDellDockMst *self,
			    guint8 cmd,
			    guint32 length,
			    guint32 offset,
			    const guint8 *data,
			    GError **error);

static gboolean
fu_dell_dock_mst_read_register(FuDellDockMst *self,
			       guint32 address,
			       gsize length,
			       GBytes **bytes,
			       GError **error)
{
	FuDevice *proxy;
	g_return_val_if_fail(bytes != NULL, FALSE);
	g_return_val_if_fail(length <= 32, FALSE);

	/* write the offset we're querying */
	proxy = fu_device_get_proxy(FU_DEVICE(self), error);
	if (proxy == NULL)
		return FALSE;
	if (!fu_dell_dock_hid_i2c_write(proxy, (guint8 *)&address, 4, &mst_base_settings, error))
		return FALSE;

	/* read data for the result */
	if (!fu_dell_dock_hid_i2c_read(proxy, 0, length, bytes, &mst_base_settings, error))
		return FALSE;

	return TRUE;
}

static gboolean
fu_dell_dock_mst_write_register(FuDellDockMst *self,
				guint32 address,
				guint8 *data,
				gsize length,
				GError **error)
{
	FuDevice *proxy;
	gsize bufsz = length + 4;
	g_autofree guint8 *buf = g_malloc0(bufsz);

	g_return_val_if_fail(data != NULL, FALSE);

	if (!fu_memwrite_uint32_safe(buf, bufsz, 0x0, address, G_LITTLE_ENDIAN, error))
		return FALSE;
	if (!fu_memcpy_safe(buf, bufsz, 0x4, data, length, 0x0, length, error))
		return FALSE;

	/* write the offset we're querying */
	proxy = fu_device_get_proxy(FU_DEVICE(self), error);
	if (proxy == NULL)
		return FALSE;
	return fu_dell_dock_hid_i2c_write(proxy, buf, bufsz, &mst_base_settings, error);
}

static gboolean
fu_dell_dock_mst_query_active_bank(FuDellDockMst *self, FuDellDockMstBank *active, GError **error)
{
	g_autoptr(GBytes) bytes = NULL;
	const guint32 *data = NULL;
	gsize length = 4;

	if (!fu_dell_dock_mst_read_register(self,
					    PANAMERA_MST_CORE_MCU_BOOTLOADER_STS,
					    length,
					    &bytes,
					    error)) {
		g_prefix_error_literal(error, "failed to query active bank: ");
		return FALSE;
	}

	data = g_bytes_get_data(bytes, &length);
	if ((data[0] & (1 << 7)) || (data[0] & (1 << 30)))
		*active = FU_DELL_DOCK_MST_BANK_1;
	else
		*active = FU_DELL_DOCK_MST_BANK_0;
	g_debug("MST: active bank is: %u", *active);

	return TRUE;
}

static gboolean
fu_dell_dock_mst_disable_remote_control(FuDellDockMst *self, GError **error)
{
	g_debug("MST: Disabling remote control");
	return fu_dell_dock_mst_rc_command(self,
					   FU_DELL_DOCK_MST_CMD_DISABLE_REMOTE_CONTROL,
					   0,
					   0,
					   NULL,
					   error);
}

static gboolean
fu_dell_dock_mst_enable_remote_control(FuDellDockMst *self, GError **error)
{
	g_autoptr(GError) error_local = NULL;
	const gchar *data = "PRIUS";

	g_debug("MST: Enabling remote control");
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_ENABLE_REMOTE_CONTROL,
					 5,
					 0,
					 (guint8 *)data,
					 &error_local)) {
		g_debug("Failed to enable remote control: %s", error_local->message);
		/* try to disable / re-enable */
		if (!fu_dell_dock_mst_disable_remote_control(self, error))
			return FALSE;
		return fu_dell_dock_mst_enable_remote_control(self, error);
	}
	return TRUE;
}

static gboolean
fu_dell_dock_mst_trigger_rc_command(FuDellDockMst *self, GError **error)
{
	const guint8 *result = NULL;
	guint32 tmp;

	/* trigger the write */
	tmp = MST_TRIGGER_WRITE;
	if (!fu_dell_dock_mst_write_register(self,
					     self->mst_rc_trigger_addr,
					     (guint8 *)&tmp,
					     sizeof(guint32),
					     error)) {
		g_prefix_error_literal(error, "failed to write MST_RC_TRIGGER_ADDR: ");
		return FALSE;
	}
	/* poll for completion */
	tmp = 0xffff;
	for (guint i = 0; i < 1000; i++) {
		g_autoptr(GBytes) bytes = NULL;
		if (!fu_dell_dock_mst_read_register(self,
						    self->mst_rc_command_addr,
						    sizeof(guint32),
						    &bytes,
						    error)) {
			g_prefix_error_literal(error, "failed to poll MST_RC_COMMAND_ADDR: ");
			return FALSE;
		}
		result = g_bytes_get_data(bytes, NULL);
		if (g_bytes_get_size(bytes) < 4)
			continue;
		/* complete */
		if ((result[2] & 0x80) == 0) {
			tmp = result[3];
			break;
		}
		fu_device_sleep(FU_DEVICE(self), 2); /* ms */
	}
	switch (tmp) {
	/* need to enable remote control */
	case 4:
		return fu_dell_dock_mst_enable_remote_control(self, error);
	/* error scenarios */
	case 3:
		g_set_error_literal(error, FWUPD_ERROR, FWUPD_ERROR_INTERNAL, "Unknown error");
		return FALSE;
	case 2:
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_NOT_SUPPORTED,
				    "Unsupported command");
		return FALSE;
	case 1:
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INVALID_DATA,
				    "Invalid argument");
		return FALSE;
	/* success scenario */
	case 0:
		return TRUE;

	default:
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_TIMED_OUT,
			    "command timed out or unknown failure: 0x%x",
			    tmp);
		return FALSE;
	}
}

static gboolean
fu_dell_dock_mst_rc_command(FuDellDockMst *self,
			    guint8 cmd,
			    guint32 length,
			    guint32 offset,
			    const guint8 *data,
			    GError **error)
{
	/* 4 for cmd, 4 for offset, 4 for length, 4 for garbage */
	gsize bufsz = (data == NULL) ? 12 : (gsize)length + 16;
	g_autofree guint8 *buf = g_malloc0(bufsz);

	/* command, offset, length, data */
	if (!fu_memwrite_uint32_safe(buf, bufsz, 0, (cmd | 0x80) << 16, G_LITTLE_ENDIAN, error))
		return FALSE;
	if (!fu_memwrite_uint32_safe(buf, bufsz, 4, offset, G_LITTLE_ENDIAN, error))
		return FALSE;
	if (!fu_memwrite_uint32_safe(buf, bufsz, 8, length, G_LITTLE_ENDIAN, error))
		return FALSE;
	if (data != NULL) {
		if (!fu_memcpy_safe(buf, bufsz, 16, data, length, 0x0, length, error))
			return FALSE;
	}

	/* write the combined register stream */
	if (!fu_dell_dock_mst_write_register(self, self->mst_rc_command_addr, buf, bufsz, error))
		return FALSE;

	return fu_dell_dock_mst_trigger_rc_command(self, error);
}

static FuDellDockMstType
fu_dell_dock_mst_get_module_type(FuDellDockMst *self)
{
	return self->mst_type;
}

static gboolean
fu_dell_dock_mst_check_offset(guint8 byte, guint8 offset)
{
	if ((byte & offset) != 0)
		return TRUE;
	return FALSE;
}

static gboolean
fu_dell_dock_mst_d19_check_fw(FuDellDockMst *self, GError **error)
{
	g_autoptr(GBytes) bytes = NULL;
	const guint8 *data;
	gsize length = 4;

	if (!fu_dell_dock_mst_read_register(self,
					    self->mst_core_mcu_bootloader_addr,
					    length,
					    &bytes,
					    error))
		return FALSE;
	data = g_bytes_get_data(bytes, &length);
	if (length < 4) {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_INVALID_DATA,
			    "MST register data too small, got %" G_GSIZE_FORMAT,
			    length);
		return FALSE;
	}

	g_debug("MST: firmware check: %d", fu_dell_dock_mst_check_offset(data[0], 0x01));
	g_debug("MST: HDCP key check: %d", fu_dell_dock_mst_check_offset(data[0], 0x02));
	g_debug("MST: Config0  check: %d", fu_dell_dock_mst_check_offset(data[0], 0x04));
	g_debug("MST: Config1  check: %d", fu_dell_dock_mst_check_offset(data[0], 0x08));

	if (fu_dell_dock_mst_check_offset(data[0], 0xF0))
		g_debug("MST: running in bootloader");
	else
		g_debug("MST: running in firmware");
	g_debug("MST: Error code: %x", data[1]);
	g_debug("MST: GPIO boot strap record: %d", data[2]);
	g_debug("MST: Bootloader version number %x", data[3]);

	return TRUE;
}

static gboolean
fu_dell_dock_mst_checksum_bank(FuDellDockMst *self,
			       GBytes *blob_fw,
			       FuDellDockMstBank bank,
			       gboolean *checksum,
			       GError **error)
{
	g_autoptr(GBytes) csum_bytes = NULL;
	const FuDellDockMstBankAttributes *attribs = NULL;
	gsize length = 0;
	const guint8 *data = g_bytes_get_data(blob_fw, &length);
	guint32 payload_sum = 0;
	guint32 bank_sum = 0;

	g_return_val_if_fail(blob_fw != NULL, FALSE);
	g_return_val_if_fail(checksum != NULL, FALSE);

	if (!fu_dell_dock_mst_get_bank_attribs(bank, &attribs, error))
		return FALSE;

	/* bank is specified outside of payload */
	if (attribs->start + attribs->length > length) {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_NOT_SUPPORTED,
			    "payload %u is bigger than bank %u",
			    attribs->start + attribs->length,
			    bank);
		return FALSE;
	}

	/* checksum the file */
	if (attribs->checksum_cmd == FU_DELL_DOCK_MST_CMD_CRC16_CHECKSUM) {
		guint16 crc_tmp = 0;
		if (!fu_crc16_safe(FU_CRC_KIND_B16_UMTS,
				   data,
				   length,
				   0x0,
				   attribs->length + attribs->start,
				   &crc_tmp,
				   error))
			return FALSE;
		payload_sum = crc_tmp;
	} else {
		for (guint i = attribs->start; i < attribs->length + attribs->start; i++) {
			payload_sum += data[i];
		}
	}
	g_debug("MST: Payload checksum: 0x%x", payload_sum);

	/* checksum the bank */
	if (!fu_dell_dock_mst_rc_command(self,
					 attribs->checksum_cmd,
					 attribs->length,
					 attribs->start,
					 NULL,
					 error)) {
		g_prefix_error(error, "failed to checksum bank %u: ", bank);
		return FALSE;
	}
	/* read result from data register */
	if (!fu_dell_dock_mst_read_register(self, self->mst_rc_data_addr, 4, &csum_bytes, error))
		return FALSE;
	if (g_bytes_get_size(csum_bytes) < 4) {
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INTERNAL,
				    "checksum result too small");
		return FALSE;
	}
	data = g_bytes_get_data(csum_bytes, NULL);
	bank_sum = GUINT32_FROM_LE(data[0] | data[1] << 8 | /* nocheck:blocked nocheck:endian */
				   data[2] << 16 | data[3] << 24);
	g_debug("MST: Bank %u checksum: 0x%x", bank, bank_sum);

	*checksum = (bank_sum == payload_sum);

	return TRUE;
}

static gboolean
fu_dell_dock_mst_erase_panamera_bank(FuDellDockMst *self, FuDellDockMstBank bank, GError **error)
{
	const FuDellDockMstBankAttributes *attribs = NULL;
	guint32 sector;

	if (!fu_dell_dock_mst_get_bank_attribs(bank, &attribs, error))
		return FALSE;

	for (guint32 i = attribs->start; i < attribs->start + attribs->length; i += 0x10000) {
		sector = FLASH_SECTOR_ERASE_64K | (i / 0x10000);
		g_debug("MST: Erasing sector 0x%x", sector);
		if (!fu_dell_dock_mst_rc_command(self,
						 FU_DELL_DOCK_MST_CMD_ERASE_FLASH,
						 4,
						 0,
						 (guint8 *)&sector,
						 error)) {
			g_prefix_error(error, "failed to erase sector 0x%x: ", sector);
			return FALSE;
		}
	}
	g_debug("MST: Waiting for flash clear to settle");
	fu_device_sleep(FU_DEVICE(self), 5000); /* ms */

	return TRUE;
}

static gboolean
fu_dell_dock_mst_erase_cayenne(FuDellDockMst *self, GError **error)
{
	guint8 data[4] = {0, 0x30, 0, 0};

	for (guint8 i = 0; i < 5; i++) {
		data[0] = i;
		if (!fu_dell_dock_mst_rc_command(self,
						 FU_DELL_DOCK_MST_CMD_ERASE_FLASH,
						 4,
						 0,
						 (guint8 *)&data,
						 error)) {
			g_prefix_error(error, "failed to erase sector %d: ", i);
			return FALSE;
		}
	}
	g_debug("MST: Waiting for flash clear to settle");
	fu_device_sleep(FU_DEVICE(self), 5000);

	return TRUE;
}

static gboolean
fu_dell_dock_mst_write_flash_bank(FuDellDockMst *self,
				  GBytes *blob_fw,
				  FuDellDockMstBank bank,
				  FuProgress *progress,
				  GError **error)
{
	const FuDellDockMstBankAttributes *attribs = NULL;
	gsize write_size = 32;
	guint end;
	gsize length = 0;
	const guint8 *data = g_bytes_get_data(blob_fw, &length);

	g_return_val_if_fail(blob_fw != NULL, FALSE);

	if (!fu_dell_dock_mst_get_bank_attribs(bank, &attribs, error))
		return FALSE;
	end = attribs->start + attribs->length;
	if (end > length) {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_INVALID_DATA,
			    "payload 0x%x is bigger than data 0x%x",
			    end,
			    (guint)length);
		return FALSE;
	}

	g_debug("MST: Writing payload to bank %u", bank);
	for (guint i = attribs->start; i < end; i += write_size) {
		if (!fu_dell_dock_mst_rc_command(self,
						 FU_DELL_DOCK_MST_CMD_WRITE_FLASH,
						 write_size,
						 i,
						 data + i,
						 error)) {
			g_prefix_error(error,
				       "failed to write bank %u payload offset 0x%x: ",
				       bank,
				       i);
			return FALSE;
		}
		fu_progress_set_percentage_full(progress, i - attribs->start, end - attribs->start);
	}

	return TRUE;
}

static gboolean
fu_dell_dock_mst_stop_esm(FuDellDockMst *self, GError **error)
{
	g_autoptr(GBytes) quad_bytes = NULL;
	g_autoptr(GBytes) hdcp_bytes = NULL;
	guint32 payload = 0x21;
	gsize length = sizeof(guint32);
	const guint8 *data;
	guint8 data_out[4] = {0};

	/* disable ESM first */
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_WRITE_MEMORY,
					 length,
					 PANAMERA_MST_RC_TRIGGER_ADDR,
					 (guint8 *)&payload,
					 error))
		return FALSE;

	/* waiting for ESM exit */
	fu_device_sleep(FU_DEVICE(self), 1);

	/* disable QUAD mode */
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_READ_MEMORY,
					 length,
					 PANAMERA_MST_REG_QUAD_DISABLE,
					 NULL,
					 error))
		return FALSE;

	if (!fu_dell_dock_mst_read_register(self,
					    PANAMERA_MST_RC_DATA_ADDR,
					    length,
					    &quad_bytes,
					    error))
		return FALSE;

	data = g_bytes_get_data(quad_bytes, &length);
	if (!fu_memcpy_safe(data_out,
			    sizeof(data_out),
			    0x0, /* dst */
			    data,
			    length,
			    0x0, /* src */
			    length,
			    error))
		return FALSE;
	data_out[0] = 0x00;
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_WRITE_MEMORY,
					 length,
					 PANAMERA_MST_REG_QUAD_DISABLE,
					 data_out,
					 error))
		return FALSE;

	/* disable HDCP2.2 */
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_READ_MEMORY,
					 length,
					 PANAMERA_MST_REG_HDCP22_DISABLE,
					 NULL,
					 error))
		return FALSE;

	if (!fu_dell_dock_mst_read_register(self,
					    PANAMERA_MST_RC_DATA_ADDR,
					    length,
					    &hdcp_bytes,
					    error))
		return FALSE;

	data = g_bytes_get_data(hdcp_bytes, &length);
	if (!fu_memcpy_safe(data_out,
			    sizeof(data_out),
			    0x0, /* dst */
			    data,
			    length,
			    0x0, /* src */
			    length,
			    error))
		return FALSE;
	data_out[0] = data[0] & (1 << 2);
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_WRITE_MEMORY,
					 length,
					 PANAMERA_MST_REG_HDCP22_DISABLE,
					 data_out,
					 error))
		return FALSE;

	return TRUE;
}

static gboolean
fu_dell_dock_mst_invalidate_bank(FuDellDockMst *self, FuDellDockMstBank bank_in_use, GError **error)
{
	const FuDellDockMstBankAttributes *attribs;
	g_autoptr(GBytes) bytes = NULL;
	const guint8 *crc_tag;
	const guint8 *new_tag;
	gsize crc_len = 0;
	guint32 crc_offset;
	guint retries = 2;

	if (!fu_dell_dock_mst_get_bank_attribs(bank_in_use, &attribs, error)) {
		g_prefix_error_literal(error, "unable to invalidate bank: ");
		return FALSE;
	}
	/* we need to write 4 byte increments over I2C so this differs from DP aux */
	crc_offset = attribs->start + EEPROM_TAG_OFFSET + 12;

	/* read CRC byte to flip */
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_READ_FLASH,
					 4,
					 crc_offset,
					 NULL,
					 error)) {
		g_prefix_error_literal(error, "failed to read tag from flash: ");
		return FALSE;
	}
	if (!fu_dell_dock_mst_read_register(self, PANAMERA_MST_RC_DATA_ADDR, 4, &bytes, error))
		return FALSE;
	crc_tag = g_bytes_get_data(bytes, &crc_len);
	if (crc_len < 4) {
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INVALID_DATA,
				    "CRC tag response invalid");
		return FALSE;
	}
	g_debug("CRC byte is currently 0x%x", crc_tag[3]);

	for (guint32 retries_cnt = 0;; retries_cnt++) {
		g_autoptr(GBytes) bytes_new = NULL;
		/* CRC8 is not 0xff, erase last 4k of bank# */
		if (crc_tag[3] != 0xff) {
			guint32 sector = FLASH_SECTOR_ERASE_4K +
					 (attribs->start + attribs->length - 0x1000) / 0x1000;
			g_debug("erasing 4k from sector 0x%x invalidate bank %u",
				sector,
				bank_in_use);
			/* offset for last 4k of bank# */
			if (!fu_dell_dock_mst_rc_command(self,
							 FU_DELL_DOCK_MST_CMD_ERASE_FLASH,
							 4,
							 0,
							 (guint8 *)&sector,
							 error)) {
				g_prefix_error(error, "failed to erase sector 0x%x: ", sector);
				return FALSE;
			}
			/* CRC8 is 0xff, set it to 0x00 */
		} else {
			guint32 write = 0x00;
			g_debug("writing 0x00 byte to 0x%x to invalidate bank %u",
				crc_offset,
				bank_in_use);
			if (!fu_dell_dock_mst_rc_command(self,
							 FU_DELL_DOCK_MST_CMD_WRITE_FLASH,
							 4,
							 crc_offset,
							 (guint8 *)&write,
							 error)) {
				g_prefix_error_literal(error, "failed to clear CRC byte: ");
				return FALSE;
			}
		}
		/* re-read for comparison */
		if (!fu_dell_dock_mst_rc_command(self,
						 FU_DELL_DOCK_MST_CMD_READ_FLASH,
						 4,
						 crc_offset,
						 NULL,
						 error)) {
			g_prefix_error_literal(error, "failed to read tag from flash: ");
			return FALSE;
		}
		if (!fu_dell_dock_mst_read_register(self,
						    PANAMERA_MST_RC_DATA_ADDR,
						    4,
						    &bytes_new,
						    error)) {
			return FALSE;
		}
		new_tag = g_bytes_get_data(bytes_new, NULL);
		if (g_bytes_get_size(bytes_new) < 4) {
			g_set_error_literal(error,
					    FWUPD_ERROR,
					    FWUPD_ERROR_INTERNAL,
					    "CRC tag result too small");
			return FALSE;
		}
		g_debug("CRC byte is currently 0x%x", new_tag[3]);

		/* tag successfully cleared */
		if ((new_tag[3] == 0xff && crc_tag[3] != 0xff) ||
		    (new_tag[3] == 0x00 && crc_tag[3] == 0xff)) {
			break;
		}
		if (retries_cnt > retries) {
			g_set_error(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INVALID_DATA,
				    "set tag invalid fail (new 0x%x; old 0x%x)",
				    new_tag[3],
				    crc_tag[3]);
			return FALSE;
		}
	}

	return TRUE;
}

static gboolean
fu_dell_dock_mst_write_bank(FuDellDockMst *self,
			    GBytes *fw,
			    guint8 bank,
			    FuProgress *progress,
			    GError **error)
{
	const guint retries = 2;
	for (guint i = 0; i < retries; i++) {
		gboolean checksum = FALSE;

		/* progress */
		fu_progress_set_id(progress, G_STRLOC);
		fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_ERASE, 15, NULL);
		fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_WRITE, 84, NULL);
		fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_VERIFY, 1, NULL);

		if (!fu_dell_dock_mst_erase_panamera_bank(self, bank, error))
			return FALSE;
		fu_progress_step_done(progress);

		if (!fu_dell_dock_mst_write_flash_bank(self,
						       fw,
						       bank,
						       fu_progress_get_child(progress),
						       error))
			return FALSE;
		fu_progress_step_done(progress);

		if (!fu_dell_dock_mst_checksum_bank(self, fw, bank, &checksum, error))
			return FALSE;
		if (!checksum) {
			g_debug("MST: Failed to verify checksum on bank %u", bank);
			fu_progress_reset(progress);
			continue;
		}
		fu_progress_step_done(progress);

		g_debug("MST: Bank %u successfully flashed", bank);
		return TRUE;
	}

	/* failed after all our retries */
	g_set_error(error, FWUPD_ERROR, FWUPD_ERROR_INTERNAL, "failed to write to bank %u", bank);
	return FALSE;
}

static FuProgress *
fu_dell_dock_mst_set_local_progress(FuProgress *progress, guint steps)
{
	FuProgress *progress_local;
	progress_local = fu_progress_get_child(progress);
	fu_progress_set_id(progress_local, G_STRLOC);
	fu_progress_set_steps(progress_local, steps);

	return progress_local;
}

static gboolean
fu_dell_dock_mst_write_panamera(FuDellDockMst *self,
				GBytes *fw,
				FwupdInstallFlags flags,
				FuProgress *progress,
				GError **error)
{
	gboolean checksum = FALSE;
	FuDellDockMstBank bank_in_use = 0;
	guint8 order[2] = {FU_DELL_DOCK_MST_BANK_ESM, FU_DELL_DOCK_MST_BANK_0};
	FuProgress *progress_local;

	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_BUSY, 1, "stop-esm");
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_WRITE, 99, NULL);

	/* determine the flash order */
	if (!fu_dell_dock_mst_query_active_bank(self, &bank_in_use, error))
		return FALSE;

	if (bank_in_use == FU_DELL_DOCK_MST_BANK_0)
		order[1] = FU_DELL_DOCK_MST_BANK_1;
	/* ESM needs special handling during flash process*/
	if (!fu_dell_dock_mst_stop_esm(self, error))
		return FALSE;
	fu_progress_step_done(progress);

	progress_local = fu_dell_dock_mst_set_local_progress(progress, 2);
	/* write each bank in order */
	for (guint phase = 0; phase < 2; phase++) {
		g_debug("MST: Checking bank %u", order[phase]);
		if (!fu_dell_dock_mst_checksum_bank(self, fw, order[phase], &checksum, error))
			return FALSE;
		if (checksum) {
			g_debug("MST: bank %u is already up to date", order[phase]);
			fu_progress_step_done(progress_local);
			continue;
		}
		g_debug("MST: bank %u needs to be updated", order[phase]);
		if (!fu_dell_dock_mst_write_bank(self,
						 fw,
						 order[phase],
						 fu_progress_get_child(progress_local),
						 error))
			return FALSE;
		fu_progress_step_done(progress_local);
	}
	/* invalidate the previous bank */
	if (!fu_dell_dock_mst_invalidate_bank(self, bank_in_use, error)) {
		g_prefix_error(error, "failed to invalidate bank %u: ", bank_in_use);
		return FALSE;
	}
	fu_progress_step_done(progress);

	return TRUE;
}

static gboolean
fu_dell_dock_mst_write_cayenne(FuDellDockMst *self,
			       GBytes *fw,
			       FwupdInstallFlags flags,
			       FuProgress *progress,
			       GError **error)
{
	gboolean checksum = FALSE;
	guint retries = 2;

	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_ERASE, 3, NULL);
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_WRITE, 97, NULL);

	for (guint i = 0; i < retries; i++) {
		if (!fu_dell_dock_mst_erase_cayenne(self, error))
			return FALSE;
		fu_progress_step_done(progress);
		if (!fu_dell_dock_mst_write_flash_bank(self,
						       fw,
						       FU_DELL_DOCK_MST_BANK_CAYENNE,
						       fu_progress_get_child(progress),
						       error))
			return FALSE;
		if (!fu_dell_dock_mst_checksum_bank(self,
						    fw,
						    FU_DELL_DOCK_MST_BANK_CAYENNE,
						    &checksum,
						    error))
			return FALSE;
		fu_progress_step_done(progress);
		if (!checksum) {
			g_debug("MST: Failed to verify checksum");
			fu_progress_reset(progress);
			continue;
		}
		break;
	}
	/* failed after all our retries */
	if (!checksum) {
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INTERNAL,
				    "failed to write to bank");
		return FALSE;
	}
	/* activate the FW */
	if (!fu_dell_dock_mst_rc_command(self,
					 FU_DELL_DOCK_MST_CMD_ACTIVATE_FW,
					 g_bytes_get_size(fw),
					 0x0,
					 NULL,
					 error)) {
		g_prefix_error_literal(error, "failed to activate FW: ");
		return FALSE;
	}
	return TRUE;
}

static gboolean
fu_dell_dock_mst_write_firmware(FuDevice *device,
				FuFirmware *firmware,
				FuProgress *progress,
				FwupdInstallFlags flags,
				GError **error)
{
	FuDellDockMst *self = FU_DELL_DOCK_MST(device);
	FuDevice *proxy;
	const guint8 *data;
	g_autofree gchar *dynamic_version = NULL;
	g_autoptr(GBytes) fw = NULL;
	FuDellDockMstType type;
	gsize datasz;
	guint8 major_version = 0;
	guint8 minor_version = 0;
	guint8 build_version = 0;

	g_return_val_if_fail(device != NULL, FALSE);
	g_return_val_if_fail(FU_IS_FIRMWARE(firmware), FALSE);

	/* open the hub*/
	proxy = fu_device_get_proxy(FU_DEVICE(self), error);
	if (proxy == NULL)
		return FALSE;
	if (!fu_device_open(proxy, error))
		return FALSE;

	/* open up access to controller bus */
	if (!fu_dell_dock_set_power(device, self->unlock_target, TRUE, error))
		return FALSE;

	/* get default image */
	fw = fu_firmware_get_bytes(firmware, error);
	if (fw == NULL)
		return FALSE;
	data = g_bytes_get_data(fw, &datasz);
	if (!fu_memread_uint8_safe(data, datasz, self->blob_major_offset, &major_version, error))
		return FALSE;
	if (!fu_memread_uint8_safe(data, datasz, self->blob_minor_offset, &minor_version, error))
		return FALSE;
	if (!fu_memread_uint8_safe(data, datasz, self->blob_build_offset, &build_version, error))
		return FALSE;
	dynamic_version =
	    g_strdup_printf("%02x.%02x.%02x", major_version, minor_version, build_version);
	g_info("writing MST firmware version %s", dynamic_version);

	/* enable remote control */
	if (!fu_dell_dock_mst_enable_remote_control(self, error))
		return FALSE;

	type = fu_dell_dock_mst_get_module_type(self);
	if (type == FU_DELL_DOCK_MST_TYPE_PANAMERA) {
		if (!fu_dell_dock_mst_write_panamera(self, fw, flags, progress, error))
			return FALSE;
	} else if (type == FU_DELL_DOCK_MST_TYPE_CAYENNE) {
		if (!fu_dell_dock_mst_write_cayenne(self, fw, flags, progress, error))
			return FALSE;
	} else {
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_NOT_SUPPORTED,
				    "Unknown mst found");
		return FALSE;
	}

	/* dock will reboot to re-read; this is to appease the daemon */
	fu_device_set_version_format(device, FWUPD_VERSION_FORMAT_TRIPLET);
	fu_device_set_version(device, dynamic_version);

	/* disable remote control now */
	return fu_dell_dock_mst_disable_remote_control(self, error);
}

static gboolean
fu_dell_dock_mst_set_quirk_kv(FuDevice *device,
			      const gchar *key,
			      const gchar *value,
			      GError **error)
{
	FuDellDockMst *self = FU_DELL_DOCK_MST(device);
	guint64 tmp = 0;

	if (g_strcmp0(key, "DellDockUnlockTarget") == 0) {
		if (!fu_strtoull(value, &tmp, 0, G_MAXUINT8, FU_INTEGER_BASE_AUTO, error))
			return FALSE;
		self->unlock_target = tmp;
		return TRUE;
	}
	if (g_strcmp0(key, "DellDockBlobMajorOffset") == 0) {
		if (!fu_strtoull(value, &tmp, 0, G_MAXUINT32, FU_INTEGER_BASE_AUTO, error))
			return FALSE;
		self->blob_major_offset = tmp;
		return TRUE;
	}
	if (g_strcmp0(key, "DellDockBlobMinorOffset") == 0) {
		if (!fu_strtoull(value, &tmp, 0, G_MAXUINT32, FU_INTEGER_BASE_AUTO, error))
			return FALSE;
		self->blob_minor_offset = tmp;
		return TRUE;
	}
	if (g_strcmp0(key, "DellDockBlobBuildOffset") == 0) {
		if (!fu_strtoull(value, &tmp, 0, G_MAXUINT32, FU_INTEGER_BASE_AUTO, error))
			return FALSE;
		self->blob_build_offset = tmp;
		return TRUE;
	}
	if (g_strcmp0(key, "DellDockInstallDurationI2C") == 0) {
		if (!fu_strtoull(value, &tmp, 0, 60 * 60 * 24, FU_INTEGER_BASE_AUTO, error))
			return FALSE;
		fu_device_set_install_duration(device, tmp);
		return TRUE;
	}

	/* failed */
	g_set_error_literal(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_NOT_SUPPORTED,
			    "quirk key not supported");
	return FALSE;
}

static gboolean
fu_dell_dock_mst_setup(FuDevice *device, GError **error)
{
	FuDellDockMst *self = FU_DELL_DOCK_MST(device);
	FuDevice *parent;
	const gchar *version;

	/* sanity check that we can talk to MST */
	if (!fu_dell_dock_mst_d19_check_fw(self, error))
		return FALSE;

	/* set version from EC if we know it */
	parent = fu_device_get_parent(device, error);
	if (parent == NULL)
		return FALSE;
	version = fu_dell_dock_ec_get_mst_version(FU_DELL_DOCK_EC(parent));
	if (version != NULL) {
		fu_device_set_version_format(device, FWUPD_VERSION_FORMAT_TRIPLET);
		fu_device_set_version(device, version);
	}

	return TRUE;
}

static gboolean
fu_dell_dock_mst_probe(FuDevice *device, GError **error)
{
	FuDellDockMst *self = FU_DELL_DOCK_MST(device);

	/* logical id */
	fu_device_set_logical_id(FU_DEVICE(device), "mst");

	/* instance id */
	if (self->dock_type == DOCK_BASE_TYPE_ATOMIC) {
		self->mst_type = FU_DELL_DOCK_MST_TYPE_CAYENNE;
		self->mst_rc_trigger_addr = CAYENNE_MST_RC_TRIGGER_ADDR;
		self->mst_rc_command_addr = CAYENNE_MST_RC_COMMAND_ADDR;
		self->mst_rc_data_addr = CAYENNE_MST_RC_DATA_ADDR;
		self->mst_core_mcu_bootloader_addr = CAYENNE_MST_CORE_MCU_BOOTLOADER_STS;
		fu_device_add_flag(device, FWUPD_DEVICE_FLAG_SIGNED_PAYLOAD);
		fu_device_add_instance_id(device, DELL_DOCK_VMM6210_INSTANCE_ID);
	} else if (self->dock_type == DOCK_BASE_TYPE_SALOMON) {
		self->mst_type = FU_DELL_DOCK_MST_TYPE_PANAMERA;
		self->mst_rc_trigger_addr = PANAMERA_MST_RC_TRIGGER_ADDR;
		self->mst_rc_command_addr = PANAMERA_MST_RC_COMMAND_ADDR;
		self->mst_rc_data_addr = PANAMERA_MST_RC_DATA_ADDR;
		self->mst_core_mcu_bootloader_addr = PANAMERA_MST_CORE_MCU_BOOTLOADER_STS;
		fu_device_add_flag(device, FWUPD_DEVICE_FLAG_UNSIGNED_PAYLOAD);
		fu_device_add_instance_id(device, DELL_DOCK_VM5331_INSTANCE_ID);
	} else {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_NOT_SUPPORTED,
			    "unknown dock type 0x%x",
			    self->dock_type);
		return FALSE;
	}

	return TRUE;
}

static gboolean
fu_dell_dock_mst_open(FuDevice *device, GError **error)
{
	FuDellDockMst *self = FU_DELL_DOCK_MST(device);
	FuDevice *proxy;
	FuDevice *parent = fu_device_get_parent(device, NULL);

	g_return_val_if_fail(self->unlock_target != 0, FALSE);
	g_return_val_if_fail(parent != NULL, FALSE);

	if (fu_device_get_proxy(device, NULL) == NULL)
		fu_device_set_proxy(device, fu_device_get_proxy(parent, NULL));

	proxy = fu_device_get_proxy(device, error);
	if (proxy == NULL)
		return FALSE;
	if (!fu_device_open(proxy, error))
		return FALSE;

	/* open up access to controller bus */
	if (!fu_dell_dock_set_power(device, self->unlock_target, TRUE, error))
		return FALSE;

	return TRUE;
}

static gboolean
fu_dell_dock_mst_close(FuDevice *device, GError **error)
{
	FuDellDockMst *self = FU_DELL_DOCK_MST(device);
	FuDevice *proxy;

	/* close access to controller bus */
	if (!fu_dell_dock_set_power(device, self->unlock_target, FALSE, error))
		return FALSE;

	proxy = fu_device_get_proxy(FU_DEVICE(self), error);
	if (proxy == NULL)
		return FALSE;
	return fu_device_close(proxy, error);
}

static void
fu_dell_dock_mst_set_progress(FuDevice *device, FuProgress *progress)
{
	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_add_step(progress, FWUPD_STATUS_DECOMPRESSING, 0, "prepare-fw");
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_RESTART, 0, "detach");
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_WRITE, 100, "write");
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_RESTART, 0, "attach");
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_BUSY, 0, "reload");
}

static void
fu_dell_dock_mst_init(FuDellDockMst *self)
{
	fu_device_add_protocol(FU_DEVICE(self), "com.synaptics.mst");
	fu_device_add_flag(FU_DEVICE(self), FWUPD_DEVICE_FLAG_UPDATABLE);
	fu_device_set_proxy_gtype(FU_DEVICE(self), FU_TYPE_HID_DEVICE);
}

static void
fu_dell_dock_mst_class_init(FuDellDockMstClass *klass)
{
	FuDeviceClass *device_class = FU_DEVICE_CLASS(klass);
	device_class->probe = fu_dell_dock_mst_probe;
	device_class->open = fu_dell_dock_mst_open;
	device_class->close = fu_dell_dock_mst_close;
	device_class->setup = fu_dell_dock_mst_setup;
	device_class->write_firmware = fu_dell_dock_mst_write_firmware;
	device_class->set_quirk_kv = fu_dell_dock_mst_set_quirk_kv;
	device_class->set_progress = fu_dell_dock_mst_set_progress;
}

FuDellDockMst *
fu_dell_dock_mst_new(FuContext *ctx, guint8 dock_type)
{
	FuDellDockMst *self = NULL;
	self = g_object_new(FU_TYPE_DELL_DOCK_MST, "context", ctx, NULL);
	self->dock_type = dock_type;
	return self;
}
