mmc: Add new VUB300 USB-to-SD/SDIO/MMC driver

Add a driver for Elan Digital System's VUB300 chip which is a USB
connected SDIO/SDmem/MMC host controller.  A VUB300 chip enables a USB 2.0
or USB 1.1 connected host computer to use SDIO/SD/MMC cards without the
need for a directly connected, for example via PCI, SDIO host controller.
Signed-off-by: Anthony F Olech <tony.olech@elandigitalsystems.com>
[cjb: various punctuation and style fixes]
Tested-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

MAINTAINERS

@@ -6778,6 +6778,13 @@ L:	lm-sensors@lm-sensors.org
 S:	Maintained
 F:	drivers/hwmon/vt8231.c
 
+VUB300 USB to SDIO/SD/MMC bridge chip
+M:	Tony Olech <tony.olech@elandigitalsystems.com>
+L:	linux-mmc@vger.kernel.org
+L:	linux-usb@vger.kernel.org
+S:	Supported
+F:	drivers/mmc/host/vub300.c
+
 W1 DALLAS'S 1-WIRE BUS
 M:	Evgeniy Polyakov <johnpol@2ka.mipt.ru>
 S:	Maintained

drivers/mmc/host/Kconfig

@@ -535,6 +535,37 @@ config MMC_JZ4740
 	  If you have a board based on such a SoC and with a SD/MMC slot,
 	  say Y or M here.
 
+config MMC_VUB300
+	tristate "VUB300 USB to SDIO/SD/MMC Host Controller support"
+	depends on USB
+	help
+	  This selects support for Elan Digital Systems' VUB300 chip.
+
+	  The VUB300 is a USB-SDIO Host Controller Interface chip
+	  that enables the host computer to use SDIO/SD/MMC cards
+	  via a USB 2.0 or USB 1.1 host.
+
+	  The VUB300 chip will be found in both physically separate
+	  USB to SDIO/SD/MMC adapters and embedded on some motherboards.
+
+	  The VUB300 chip supports SD and MMC memory cards in addition
+	  to single and multifunction SDIO cards.
+
+	  Some SDIO cards will need a firmware file to be loaded and
+	  sent to VUB300 chip in order to achieve better data throughput.
+	  Download these "Offload Pseudocode" from Elan Digital Systems'
+	  web-site http://www.elandigitalsystems.com/support/downloads.php
+	  and put them in /lib/firmware. Note that without these additional
+	  firmware files the VUB300 chip will still function, but not at
+	  the best obtainable data rate.
+
+	  To compile this mmc host controller driver as a module,
+	  choose M here: the module will be called vub300.
+
+	  If you have a computer with an embedded VUB300 chip
+	  or if you intend connecting a USB adapter based on a
+	  VUB300 chip say Y or M here.
+
 config MMC_USHC
 	tristate "USB SD Host Controller (USHC) support"
 	depends on USB

drivers/mmc/host/Makefile

@@ -41,6 +41,7 @@ obj-$(CONFIG_SDH_BFIN)		+= bfin_sdh.o
 obj-$(CONFIG_MMC_DW)		+= dw_mmc.o
 obj-$(CONFIG_MMC_SH_MMCIF)	+= sh_mmcif.o
 obj-$(CONFIG_MMC_JZ4740)	+= jz4740_mmc.o
+obj-$(CONFIG_MMC_VUB300)	+= vub300.o
 obj-$(CONFIG_MMC_USHC)		+= ushc.o
 
 obj-$(CONFIG_MMC_SDHCI_PLTFM)			+= sdhci-platform.o

drivers/mmc/host/vub300.c

+/*
+ * Remote VUB300 SDIO/SDmem Host Controller Driver
+ *
+ * Copyright (C) 2010 Elan Digital Systems Limited
+ *
+ * based on USB Skeleton driver - 2.2
+ *
+ * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2
+ *
+ * VUB300: is a USB 2.0 client device with a single SDIO/SDmem/MMC slot
+ *         Any SDIO/SDmem/MMC device plugged into the VUB300 will appear,
+ *         by virtue of this driver, to have been plugged into a local
+ *         SDIO host controller, similar to, say, a PCI Ricoh controller
+ *         This is because this kernel device driver is both a USB 2.0
+ *         client device driver AND an MMC host controller driver. Thus
+ *         if there is an existing driver for the inserted SDIO/SDmem/MMC
+ *         device then that driver will be used by the kernel to manage
+ *         the device in exactly the same fashion as if it had been
+ *         directly plugged into, say, a local pci bus Ricoh controller
+ *
+ * RANT: this driver was written using a display 128x48 - converting it
+ *       to a line width of 80 makes it very difficult to support. In
+ *       particular functions have been broken down into sub functions
+ *       and the original meaningful names have been shortened into
+ *       cryptic ones.
+ *       The problem is that executing a fragment of code subject to
+ *       two conditions means an indentation of 24, thus leaving only
+ *       56 characters for a C statement. And that is quite ridiculous!
+ *
+ * Data types: data passed to/from the VUB300 is fixed to a number of
+ *             bits and driver data fields reflect that limit by using
+ *             u8, u16, u32
+ */
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kref.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+#include <linux/mutex.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include <linux/mmc/sdio_func.h>
+#include <linux/mmc/sdio_ids.h>
+#include <linux/workqueue.h>
+#include <linux/ctype.h>
+#include <linux/firmware.h>
+#include <linux/scatterlist.h>
+
+struct host_controller_info {
+	u8 info_size;
+	u16 firmware_version;
+	u8 number_of_ports;
+} __packed;
+
+#define FIRMWARE_BLOCK_BOUNDARY 1024
+struct sd_command_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+	u8 command_type; /* Bit7 - Rd/Wr */
+	u8 command_index;
+	u8 transfer_size[4]; /* ReadSize + ReadSize */
+	u8 response_type;
+	u8 arguments[4];
+	u8 block_count[2];
+	u8 block_size[2];
+	u8 block_boundary[2];
+	u8 reserved[44]; /* to pad out to 64 bytes */
+} __packed;
+
+struct sd_irqpoll_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+	u8 command_type; /* Bit7 - Rd/Wr */
+	u8 padding[16]; /* don't ask why !! */
+	u8 poll_timeout_msb;
+	u8 poll_timeout_lsb;
+	u8 reserved[42]; /* to pad out to 64 bytes */
+} __packed;
+
+struct sd_common_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+} __packed;
+
+struct sd_response_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+	u8 command_type;
+	u8 command_index;
+	u8 command_response[0];
+} __packed;
+
+struct sd_status_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+	u16 port_flags;
+	u32 sdio_clock;
+	u16 host_header_size;
+	u16 func_header_size;
+	u16 ctrl_header_size;
+} __packed;
+
+struct sd_error_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+	u8 error_code;
+} __packed;
+
+struct sd_interrupt_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+} __packed;
+
+struct offload_registers_access {
+	u8 command_byte[4];
+	u8 Respond_Byte[4];
+} __packed;
+
+#define INTERRUPT_REGISTER_ACCESSES 15
+struct sd_offloaded_interrupt {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+	struct offload_registers_access reg[INTERRUPT_REGISTER_ACCESSES];
+} __packed;
+
+struct sd_register_header {
+	u8 header_size;
+	u8 header_type;
+	u8 port_number;
+	u8 command_type;
+	u8 command_index;
+	u8 command_response[6];
+} __packed;
+
+#define PIGGYBACK_REGISTER_ACCESSES 14
+struct sd_offloaded_piggyback {
+	struct sd_register_header sdio;
+	struct offload_registers_access reg[PIGGYBACK_REGISTER_ACCESSES];
+} __packed;
+
+union sd_response {
+	struct sd_common_header common;
+	struct sd_status_header status;
+	struct sd_error_header error;
+	struct sd_interrupt_header interrupt;
+	struct sd_response_header response;
+	struct sd_offloaded_interrupt irq;
+	struct sd_offloaded_piggyback pig;
+} __packed;
+
+union sd_command {
+	struct sd_command_header head;
+	struct sd_irqpoll_header poll;
+} __packed;
+
+enum SD_RESPONSE_TYPE {
+	SDRT_UNSPECIFIED = 0,
+	SDRT_NONE,
+	SDRT_1,
+	SDRT_1B,
+	SDRT_2,
+	SDRT_3,
+	SDRT_4,
+	SDRT_5,
+	SDRT_5B,
+	SDRT_6,
+	SDRT_7,
+};
+
+#define RESPONSE_INTERRUPT			0x01
+#define RESPONSE_ERROR				0x02
+#define RESPONSE_STATUS				0x03
+#define RESPONSE_IRQ_DISABLED			0x05
+#define RESPONSE_IRQ_ENABLED			0x06
+#define RESPONSE_PIGGYBACKED			0x07
+#define RESPONSE_NO_INTERRUPT			0x08
+#define RESPONSE_PIG_DISABLED			0x09
+#define RESPONSE_PIG_ENABLED			0x0A
+#define SD_ERROR_1BIT_TIMEOUT			0x01
+#define SD_ERROR_4BIT_TIMEOUT			0x02
+#define SD_ERROR_1BIT_CRC_WRONG			0x03
+#define SD_ERROR_4BIT_CRC_WRONG			0x04
+#define SD_ERROR_1BIT_CRC_ERROR			0x05
+#define SD_ERROR_4BIT_CRC_ERROR			0x06
+#define SD_ERROR_NO_CMD_ENDBIT			0x07
+#define SD_ERROR_NO_1BIT_DATEND			0x08
+#define SD_ERROR_NO_4BIT_DATEND			0x09
+#define SD_ERROR_1BIT_UNEXPECTED_TIMEOUT	0x0A
+#define SD_ERROR_4BIT_UNEXPECTED_TIMEOUT	0x0B
+#define SD_ERROR_ILLEGAL_COMMAND		0x0C
+#define SD_ERROR_NO_DEVICE			0x0D
+#define SD_ERROR_TRANSFER_LENGTH		0x0E
+#define SD_ERROR_1BIT_DATA_TIMEOUT		0x0F
+#define SD_ERROR_4BIT_DATA_TIMEOUT		0x10
+#define SD_ERROR_ILLEGAL_STATE			0x11
+#define SD_ERROR_UNKNOWN_ERROR			0x12
+#define SD_ERROR_RESERVED_ERROR			0x13
+#define SD_ERROR_INVALID_FUNCTION		0x14
+#define SD_ERROR_OUT_OF_RANGE			0x15
+#define SD_ERROR_STAT_CMD			0x16
+#define SD_ERROR_STAT_DATA			0x17
+#define SD_ERROR_STAT_CMD_TIMEOUT		0x18
+#define SD_ERROR_SDCRDY_STUCK			0x19
+#define SD_ERROR_UNHANDLED			0x1A
+#define SD_ERROR_OVERRUN			0x1B
+#define SD_ERROR_PIO_TIMEOUT			0x1C
+
+#define FUN(c) (0x000007 & (c->arg>>28))
+#define REG(c) (0x01FFFF & (c->arg>>9))
+
+static int limit_speed_to_24_MHz;
+module_param(limit_speed_to_24_MHz, bool, 0644);
+MODULE_PARM_DESC(limit_speed_to_24_MHz, "Limit Max SDIO Clock Speed to 24 MHz");
+
+static int pad_input_to_usb_pkt;
+module_param(pad_input_to_usb_pkt, bool, 0644);
+MODULE_PARM_DESC(pad_input_to_usb_pkt,
+		 "Pad USB data input transfers to whole USB Packet");
+
+static int disable_offload_processing;
+module_param(disable_offload_processing, bool, 0644);
+MODULE_PARM_DESC(disable_offload_processing, "Disable Offload Processing");
+
+static int force_1_bit_data_xfers;
+module_param(force_1_bit_data_xfers, bool, 0644);
+MODULE_PARM_DESC(force_1_bit_data_xfers,
+		 "Force SDIO Data Transfers to 1-bit Mode");
+
+static int force_polling_for_irqs;
+module_param(force_polling_for_irqs, bool, 0644);
+MODULE_PARM_DESC(force_polling_for_irqs, "Force Polling for SDIO interrupts");
+
+static int firmware_irqpoll_timeout = 1024;
+module_param(firmware_irqpoll_timeout, int, 0644);
+MODULE_PARM_DESC(firmware_irqpoll_timeout, "VUB300 firmware irqpoll timeout");
+
+static int force_max_req_size = 128;
+module_param(force_max_req_size, int, 0644);
+MODULE_PARM_DESC(force_max_req_size, "set max request size in kBytes");
+
+#ifdef SMSC_DEVELOPMENT_BOARD
+static int firmware_rom_wait_states = 0x04;
+#else
+static int firmware_rom_wait_states = 0x1C;
+#endif
+
+module_param(firmware_rom_wait_states, bool, 0644);
+MODULE_PARM_DESC(firmware_rom_wait_states,
+		 "ROM wait states byte=RRRIIEEE (Reserved Internal External)");
+
+#define ELAN_VENDOR_ID		0x2201
+#define VUB300_VENDOR_ID	0x0424
+#define VUB300_PRODUCT_ID	0x012C
+static struct usb_device_id vub300_table[] = {
+	{USB_DEVICE(ELAN_VENDOR_ID, VUB300_PRODUCT_ID)},
+	{USB_DEVICE(VUB300_VENDOR_ID, VUB300_PRODUCT_ID)},
+	{} /* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, vub300_table);
+
+static struct workqueue_struct *cmndworkqueue;
+static struct workqueue_struct *pollworkqueue;
+static struct workqueue_struct *deadworkqueue;
+
+static inline int interface_to_InterfaceNumber(struct usb_interface *interface)
+{
+	if (!interface)
+		return -1;
+	if (!interface->cur_altsetting)
+		return -1;
+	return interface->cur_altsetting->desc.bInterfaceNumber;
+}
+
+struct sdio_register {
+	unsigned func_num:3;
+	unsigned sdio_reg:17;
+	unsigned activate:1;
+	unsigned prepared:1;
+	unsigned regvalue:8;
+	unsigned response:8;
+	unsigned sparebit:26;
+};
+
+struct vub300_mmc_host {
+	struct usb_device *udev;
+	struct usb_interface *interface;
+	struct kref kref;
+	struct mutex cmd_mutex;
+	struct mutex irq_mutex;
+	char vub_name[3 + (9 * 8) + 4 + 1]; /* max of 7 sdio fn's */
+	u8 cmnd_out_ep; /* EndPoint for commands */
+	u8 cmnd_res_ep; /* EndPoint for responses */
+	u8 data_out_ep; /* EndPoint for out data */
+	u8 data_inp_ep; /* EndPoint for inp data */
+	bool card_powered;
+	bool card_present;
+	bool read_only;
+	bool large_usb_packets;
+	bool app_spec; /* ApplicationSpecific */
+	bool irq_enabled; /* by the MMC CORE */
+	bool irq_disabled; /* in the firmware */
+	unsigned bus_width:4;
+	u8 total_offload_count;
+	u8 dynamic_register_count;
+	u8 resp_len;
+	u32 datasize;
+	int errors;
+	int usb_transport_fail;
+	int usb_timed_out;
+	int irqs_queued;
+	struct sdio_register sdio_register[16];
+	struct offload_interrupt_function_register {
+#define MAXREGBITS 4
+#define MAXREGS (1<<MAXREGBITS)
+#define MAXREGMASK (MAXREGS-1)
+		u8 offload_count;
+		u32 offload_point;
+		struct offload_registers_access reg[MAXREGS];
+	} fn[8];
+	u16 fbs[8]; /* Function Block Size */
+	struct mmc_command *cmd;
+	struct mmc_request *req;
+	struct mmc_data *data;
+	struct mmc_host *mmc;
+	struct urb *urb;
+	struct urb *command_out_urb;
+	struct urb *command_res_urb;
+	struct completion command_complete;
+	struct completion irqpoll_complete;
+	union sd_command cmnd;
+	union sd_response resp;
+	struct timer_list sg_transfer_timer;
+	struct usb_sg_request sg_request;
+	struct timer_list inactivity_timer;
+	struct work_struct deadwork;
+	struct work_struct cmndwork;
+	struct delayed_work pollwork;
+	struct host_controller_info hc_info;
+	struct sd_status_header system_port_status;
+	u8 padded_buffer[64];
+};
+
+#define kref_to_vub300_mmc_host(d) container_of(d, struct vub300_mmc_host, kref)
+#define SET_TRANSFER_PSEUDOCODE		21
+#define SET_INTERRUPT_PSEUDOCODE	20
+#define SET_FAILURE_MODE		18
+#define SET_ROM_WAIT_STATES		16
+#define SET_IRQ_ENABLE			13
+#define SET_CLOCK_SPEED			11
+#define SET_FUNCTION_BLOCK_SIZE		9
+#define SET_SD_DATA_MODE		6
+#define SET_SD_POWER			4
+#define ENTER_DFU_MODE			3
+#define GET_HC_INF0			1
+#define GET_SYSTEM_PORT_STATUS		0
+
+static void vub300_delete(struct kref *kref)
+{				/* kref callback - softirq */
+	struct vub300_mmc_host *vub300 = kref_to_vub300_mmc_host(kref);
+	struct mmc_host *mmc = vub300->mmc;
+	usb_free_urb(vub300->command_out_urb);
+	vub300->command_out_urb = NULL;
+	usb_free_urb(vub300->command_res_urb);
+	vub300->command_res_urb = NULL;
+	usb_put_dev(vub300->udev);
+	mmc_free_host(mmc);
+	/*
+	 * and hence also frees vub300
+	 * which is contained at the end of struct mmc
+	 */
+}
+
+static void vub300_queue_cmnd_work(struct vub300_mmc_host *vub300)
+{
+	kref_get(&vub300->kref);
+	if (queue_work(cmndworkqueue, &vub300->cmndwork)) {
+		/*
+		 * then the cmndworkqueue was not previously
+		 * running and the above get ref is obvious
+		 * required and will be put when the thread
+		 * terminates by a specific call
+		 */
+	} else {
+		/*
+		 * the cmndworkqueue was already running from
+		 * a previous invocation and thus to keep the
+		 * kref counts correct we must undo the get
+		 */
+		kref_put(&vub300->kref, vub300_delete);
+	}
+}
+
+static void vub300_queue_poll_work(struct vub300_mmc_host *vub300, int delay)
+{
+	kref_get(&vub300->kref);
+	if (queue_delayed_work(pollworkqueue, &vub300->pollwork, delay)) {
+		/*
+		 * then the pollworkqueue was not previously
+		 * running and the above get ref is obvious
+		 * required and will be put when the thread
+		 * terminates by a specific call
+		 */
+	} else {
+		/*
+		 * the pollworkqueue was already running from
+		 * a previous invocation and thus to keep the
+		 * kref counts correct we must undo the get
+		 */
+		kref_put(&vub300->kref, vub300_delete);
+	}
+}
+
+static void vub300_queue_dead_work(struct vub300_mmc_host *vub300)
+{
+	kref_get(&vub300->kref);
+	if (queue_work(deadworkqueue, &vub300->deadwork)) {
+		/*
+		 * then the deadworkqueue was not previously
+		 * running and the above get ref is obvious
+		 * required and will be put when the thread
+		 * terminates by a specific call
+		 */
+	} else {
+		/*
+		 * the deadworkqueue was already running from
+		 * a previous invocation and thus to keep the
+		 * kref counts correct we must undo the get
+		 */
+		kref_put(&vub300->kref, vub300_delete);
+	}
+}
+
+static void irqpoll_res_completed(struct urb *urb)
+{				/* urb completion handler - hardirq */
+	struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
+	if (urb->status)
+		vub300->usb_transport_fail = urb->status;
+	complete(&vub300->irqpoll_complete);
+}
+
+static void irqpoll_out_completed(struct urb *urb)
+{				/* urb completion handler - hardirq */
+	struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
+	if (urb->status) {
+		vub300->usb_transport_fail = urb->status;
+		complete(&vub300->irqpoll_complete);
+		return;
+	} else {
+		int ret;
+		unsigned int pipe =
+			usb_rcvbulkpipe(vub300->udev, vub300->cmnd_res_ep);
+		usb_fill_bulk_urb(vub300->command_res_urb, vub300->udev, pipe,
+				  &vub300->resp, sizeof(vub300->resp),
+				  irqpoll_res_completed, vub300);
+		vub300->command_res_urb->actual_length = 0;
+		ret = usb_submit_urb(vub300->command_res_urb, GFP_ATOMIC);
+		if (ret) {
+			vub300->usb_transport_fail = ret;
+			complete(&vub300->irqpoll_complete);
+		}
+		return;
+	}
+}
+
+static void send_irqpoll(struct vub300_mmc_host *vub300)
+{
+	/* cmd_mutex is held by vub300_pollwork_thread */
+	int retval;
+	int timeout = 0xFFFF & (0x0001FFFF - firmware_irqpoll_timeout);
+	vub300->cmnd.poll.header_size = 22;
+	vub300->cmnd.poll.header_type = 1;
+	vub300->cmnd.poll.port_number = 0;
+	vub300->cmnd.poll.command_type = 2;
+	vub300->cmnd.poll.poll_timeout_lsb = 0xFF & (unsigned)timeout;
+	vub300->cmnd.poll.poll_timeout_msb = 0xFF & (unsigned)(timeout >> 8);
+	usb_fill_bulk_urb(vub300->command_out_urb, vub300->udev,
+			  usb_sndbulkpipe(vub300->udev, vub300->cmnd_out_ep)
+			  , &vub300->cmnd, sizeof(vub300->cmnd)
+			  , irqpoll_out_completed, vub300);
+	retval = usb_submit_urb(vub300->command_out_urb, GFP_KERNEL);
+	if (0 > retval) {
+		vub300->usb_transport_fail = retval;
+		vub300_queue_poll_work(vub300, 1);
+		complete(&vub300->irqpoll_complete);
+		return;
+	} else {
+		return;
+	}
+}
+
+static void new_system_port_status(struct vub300_mmc_host *vub300)
+{
+	int old_card_present = vub300->card_present;
+	int new_card_present =
+		(0x0001 & vub300->system_port_status.port_flags) ? 1 : 0;
+	vub300->read_only =
+		(0x0010 & vub300->system_port_status.port_flags) ? 1 : 0;
+	if (new_card_present && !old_card_present) {
+		dev_info(&vub300->udev->dev, "card just inserted\n");
+		vub300->card_present = 1;
+		vub300->bus_width = 0;
+		if (disable_offload_processing)
+			strncpy(vub300->vub_name, "EMPTY Processing Disabled",
+				sizeof(vub300->vub_name));
+		else
+			vub300->vub_name[0] = 0;
+		mmc_detect_change(vub300->mmc, 1);
+	} else if (!new_card_present && old_card_present) {
+		dev_info(&vub300->udev->dev, "card just ejected\n");
+		vub300->card_present = 0;
+		mmc_detect_change(vub300->mmc, 0);
+	} else {
+		/* no change */
+	}
+}
+
+static void __add_offloaded_reg_to_fifo(struct vub300_mmc_host *vub300,
+					struct offload_registers_access
+					*register_access, u8 func)
+{
+	u8 r = vub300->fn[func].offload_point + vub300->fn[func].offload_count;
+	memcpy(&vub300->fn[func].reg[MAXREGMASK & r], register_access,
+	       sizeof(struct offload_registers_access));
+	vub300->fn[func].offload_count += 1;
+	vub300->total_offload_count += 1;
+}
+
+static void add_offloaded_reg(struct vub300_mmc_host *vub300,
+			      struct offload_registers_access *register_access)
+{
+	u32 Register = ((0x03 & register_access->command_byte[0]) << 15)
+			| ((0xFF & register_access->command_byte[1]) << 7)
+			| ((0xFE & register_access->command_byte[2]) >> 1);
+	u8 func = ((0x70 & register_access->command_byte[0]) >> 4);
+	u8 regs = vub300->dynamic_register_count;
+	u8 i = 0;
+	while (0 < regs-- && 1 == vub300->sdio_register[i].activate) {
+		if (vub300->sdio_register[i].func_num == func &&
+		    vub300->sdio_register[i].sdio_reg == Register) {
+			if (vub300->sdio_register[i].prepared == 0)
+				vub300->sdio_register[i].prepared = 1;
+			vub300->sdio_register[i].response =
+				register_access->Respond_Byte[2];
+			vub300->sdio_register[i].regvalue =
+				register_access->Respond_Byte[3];
+			return;
+		} else {
+			i += 1;
+			continue;
+		}
+	};
+	__add_offloaded_reg_to_fifo(vub300, register_access, func);
+}
+
+static void check_vub300_port_status(struct vub300_mmc_host *vub300)
+{
+	/*
+	 * cmd_mutex is held by vub300_pollwork_thread,
+	 * vub300_deadwork_thread or vub300_cmndwork_thread
+	 */
+	int retval;
+	retval =
+		usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
+				GET_SYSTEM_PORT_STATUS,
+				USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				0x0000, 0x0000, &vub300->system_port_status,
+				sizeof(vub300->system_port_status), HZ);
+	if (sizeof(vub300->system_port_status) == retval)
+		new_system_port_status(vub300);
+}
+
+static void __vub300_irqpoll_response(struct vub300_mmc_host *vub300)
+{
+	/* cmd_mutex is held by vub300_pollwork_thread */
+	if (vub300->command_res_urb->actual_length == 0)
+		return;
+
+	switch (vub300->resp.common.header_type) {
+	case RESPONSE_INTERRUPT:
+		mutex_lock(&vub300->irq_mutex);
+		if (vub300->irq_enabled)
+			mmc_signal_sdio_irq(vub300->mmc);
+		else
+			vub300->irqs_queued += 1;
+		vub300->irq_disabled = 1;
+		mutex_unlock(&vub300->irq_mutex);
+		break;
+	case RESPONSE_ERROR:
+		if (vub300->resp.error.error_code == SD_ERROR_NO_DEVICE)
+			check_vub300_port_status(vub300);
+		break;
+	case RESPONSE_STATUS:
+		vub300->system_port_status = vub300->resp.status;
+		new_system_port_status(vub300);
+		if (!vub300->card_present)
+			vub300_queue_poll_work(vub300, HZ / 5);
+		break;
+	case RESPONSE_IRQ_DISABLED:
+	{
+		int offloaded_data_length = vub300->resp.common.header_size - 3;
+		int register_count = offloaded_data_length >> 3;
+		int ri = 0;
+		while (register_count--) {
+			add_offloaded_reg(vub300, &vub300->resp.irq.reg[ri]);
+			ri += 1;
+		}
+		mutex_lock(&vub300->irq_mutex);
+		if (vub300->irq_enabled)
+			mmc_signal_sdio_irq(vub300->mmc);
+		else
+			vub300->irqs_queued += 1;
+		vub300->irq_disabled = 1;
+		mutex_unlock(&vub300->irq_mutex);
+		break;
+	}
+	case RESPONSE_IRQ_ENABLED:
+	{
+		int offloaded_data_length = vub300->resp.common.header_size - 3;
+		int register_count = offloaded_data_length >> 3;
+		int ri = 0;
+		while (register_count--) {
+			add_offloaded_reg(vub300, &vub300->resp.irq.reg[ri]);
+			ri += 1;
+		}
+		mutex_lock(&vub300->irq_mutex);
+		if (vub300->irq_enabled)
+			mmc_signal_sdio_irq(vub300->mmc);
+		else if (vub300->irqs_queued)
+			vub300->irqs_queued += 1;
+		else
+			vub300->irqs_queued += 1;
+		vub300->irq_disabled = 0;
+		mutex_unlock(&vub300->irq_mutex);
+		break;
+	}
+	case RESPONSE_NO_INTERRUPT:
+		vub300_queue_poll_work(vub300, 1);
+		break;
+	default:
+		break;
+	}
+}
+
+static void __do_poll(struct vub300_mmc_host *vub300)
+{
+	/* cmd_mutex is held by vub300_pollwork_thread */
+	long commretval;
+	mod_timer(&vub300->inactivity_timer, jiffies + HZ);
+	init_completion(&vub300->irqpoll_complete);
+	send_irqpoll(vub300);
+	commretval = wait_for_completion_timeout(&vub300->irqpoll_complete,
+						 msecs_to_jiffies(500));
+	if (vub300->usb_transport_fail) {
+		/* no need to do anything */
+	} else if (commretval == 0) {
+		vub300->usb_timed_out = 1;
+		usb_kill_urb(vub300->command_out_urb);
+		usb_kill_urb(vub300->command_res_urb);
+	} else if (commretval < 0) {
+		vub300_queue_poll_work(vub300, 1);
+	} else { /* commretval > 0 */
+		__vub300_irqpoll_response(vub300);
+	}
+}
+
+/* this thread runs only when the driver
+ * is trying to poll the device for an IRQ
+ */
+static void vub300_pollwork_thread(struct work_struct *work)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = container_of(work,
+			      struct vub300_mmc_host, pollwork.work);
+	if (!vub300->interface) {
+		kref_put(&vub300->kref, vub300_delete);
+		return;
+	}
+	mutex_lock(&vub300->cmd_mutex);
+	if (vub300->cmd) {
+		vub300_queue_poll_work(vub300, 1);
+	} else if (!vub300->card_present) {
+		/* no need to do anything */
+	} else { /* vub300->card_present */
+		mutex_lock(&vub300->irq_mutex);
+		if (!vub300->irq_enabled) {
+			mutex_unlock(&vub300->irq_mutex);
+		} else if (vub300->irqs_queued) {
+			vub300->irqs_queued -= 1;
+			mmc_signal_sdio_irq(vub300->mmc);
+			mod_timer(&vub300->inactivity_timer, jiffies + HZ);
+			mutex_unlock(&vub300->irq_mutex);
+		} else { /* NOT vub300->irqs_queued */
+			mutex_unlock(&vub300->irq_mutex);
+			__do_poll(vub300);
+		}
+	}
+	mutex_unlock(&vub300->cmd_mutex);
+	kref_put(&vub300->kref, vub300_delete);
+}
+
+static void vub300_deadwork_thread(struct work_struct *work)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 =
+		container_of(work, struct vub300_mmc_host, deadwork);
+	if (!vub300->interface) {
+		kref_put(&vub300->kref, vub300_delete);
+		return;
+	}
+	mutex_lock(&vub300->cmd_mutex);
+	if (vub300->cmd) {
+		/*
+		 * a command got in as the inactivity
+		 * timer expired - so we just let the
+		 * processing of the command show if
+		 * the device is dead
+		 */
+	} else if (vub300->card_present) {
+		check_vub300_port_status(vub300);
+	} else if (vub300->mmc && vub300->mmc->card &&
+		   mmc_card_present(vub300->mmc->card)) {
+		/*
+		 * the MMC core must not have responded
+		 * to the previous indication - lets
+		 * hope that it eventually does so we
+		 * will just ignore this for now
+		 */
+	} else {
+		check_vub300_port_status(vub300);
+	}
+	mod_timer(&vub300->inactivity_timer, jiffies + HZ);
+	mutex_unlock(&vub300->cmd_mutex);
+	kref_put(&vub300->kref, vub300_delete);
+}
+
+static void vub300_inactivity_timer_expired(unsigned long data)
+{				/* softirq */
+	struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)data;
+	if (!vub300->interface) {
+		kref_put(&vub300->kref, vub300_delete);
+	} else if (vub300->cmd) {
+		mod_timer(&vub300->inactivity_timer, jiffies + HZ);
+	} else {
+		vub300_queue_dead_work(vub300);
+		mod_timer(&vub300->inactivity_timer, jiffies + HZ);
+	}
+}
+
+static int vub300_response_error(u8 error_code)
+{
+	switch (error_code) {
+	case SD_ERROR_PIO_TIMEOUT:
+	case SD_ERROR_1BIT_TIMEOUT:
+	case SD_ERROR_4BIT_TIMEOUT:
+		return -ETIMEDOUT;
+	case SD_ERROR_STAT_DATA:
+	case SD_ERROR_OVERRUN:
+	case SD_ERROR_STAT_CMD:
+	case SD_ERROR_STAT_CMD_TIMEOUT:
+	case SD_ERROR_SDCRDY_STUCK:
+	case SD_ERROR_UNHANDLED:
+	case SD_ERROR_1BIT_CRC_WRONG:
+	case SD_ERROR_4BIT_CRC_WRONG:
+	case SD_ERROR_1BIT_CRC_ERROR:
+	case SD_ERROR_4BIT_CRC_ERROR:
+	case SD_ERROR_NO_CMD_ENDBIT:
+	case SD_ERROR_NO_1BIT_DATEND:
+	case SD_ERROR_NO_4BIT_DATEND:
+	case SD_ERROR_1BIT_DATA_TIMEOUT:
+	case SD_ERROR_4BIT_DATA_TIMEOUT:
+	case SD_ERROR_1BIT_UNEXPECTED_TIMEOUT:
+	case SD_ERROR_4BIT_UNEXPECTED_TIMEOUT:
+		return -EILSEQ;
+	case 33:
+		return -EILSEQ;
+	case SD_ERROR_ILLEGAL_COMMAND:
+		return -EINVAL;
+	case SD_ERROR_NO_DEVICE:
+		return -ENOMEDIUM;
+	default:
+		return -ENODEV;
+	}
+}
+
+static void command_res_completed(struct urb *urb)
+{				/* urb completion handler - hardirq */
+	struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
+	if (urb->status) {
+		/* we have to let the initiator handle the error */
+	} else if (vub300->command_res_urb->actual_length == 0) {
+		/*
+		 * we have seen this happen once or twice and
+		 * we suspect a buggy USB host controller
+		 */
+	} else if (!vub300->data) {
+		/* this means that the command (typically CMD52) suceeded */
+	} else if (vub300->resp.common.header_type != 0x02) {
+		/*
+		 * this is an error response from the VUB300 chip
+		 * and we let the initiator handle it
+		 */
+	} else if (vub300->urb) {
+		vub300->cmd->error =
+			vub300_response_error(vub300->resp.error.error_code);
+		usb_unlink_urb(vub300->urb);
+	} else {
+		vub300->cmd->error =
+			vub300_response_error(vub300->resp.error.error_code);
+		usb_sg_cancel(&vub300->sg_request);
+	}
+	complete(&vub300->command_complete);	/* got_response_in */
+}
+
+static void command_out_completed(struct urb *urb)
+{				/* urb completion handler - hardirq */
+	struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
+	if (urb->status) {
+		complete(&vub300->command_complete);
+	} else {
+		int ret;
+		unsigned int pipe =
+			usb_rcvbulkpipe(vub300->udev, vub300->cmnd_res_ep);
+		usb_fill_bulk_urb(vub300->command_res_urb, vub300->udev, pipe,
+				  &vub300->resp, sizeof(vub300->resp),
+				  command_res_completed, vub300);
+		vub300->command_res_urb->actual_length = 0;
+		ret = usb_submit_urb(vub300->command_res_urb, GFP_ATOMIC);
+		if (ret == 0) {
+			/*
+			 * the urb completion handler will call
+			 * our completion handler
+			 */
+		} else {
+			/*
+			 * and thus we only call it directly
+			 * when it will not be called
+			 */
+			complete(&vub300->command_complete);
+		}
+	}
+}
+
+/*
+ * the STUFF bits are masked out for the comparisons
+ */
+static void snoop_block_size_and_bus_width(struct vub300_mmc_host *vub300,
+					   u32 cmd_arg)
+{
+	if ((0xFBFFFE00 & cmd_arg) == 0x80022200)
+		vub300->fbs[1] = (cmd_arg << 8) | (0x00FF & vub300->fbs[1]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x80022000)
+		vub300->fbs[1] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[1]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x80042200)
+		vub300->fbs[2] = (cmd_arg << 8) | (0x00FF & vub300->fbs[2]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x80042000)
+		vub300->fbs[2] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[2]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x80062200)
+		vub300->fbs[3] = (cmd_arg << 8) | (0x00FF & vub300->fbs[3]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x80062000)
+		vub300->fbs[3] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[3]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x80082200)
+		vub300->fbs[4] = (cmd_arg << 8) | (0x00FF & vub300->fbs[4]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x80082000)
+		vub300->fbs[4] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[4]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x800A2200)
+		vub300->fbs[5] = (cmd_arg << 8) | (0x00FF & vub300->fbs[5]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x800A2000)
+		vub300->fbs[5] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[5]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x800C2200)
+		vub300->fbs[6] = (cmd_arg << 8) | (0x00FF & vub300->fbs[6]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x800C2000)
+		vub300->fbs[6] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[6]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x800E2200)
+		vub300->fbs[7] = (cmd_arg << 8) | (0x00FF & vub300->fbs[7]);
+	else if ((0xFBFFFE00 & cmd_arg) == 0x800E2000)
+		vub300->fbs[7] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[7]);
+	else if ((0xFBFFFE03 & cmd_arg) == 0x80000E00)
+		vub300->bus_width = 1;
+	else if ((0xFBFFFE03 & cmd_arg) == 0x80000E02)
+		vub300->bus_width = 4;
+}
+
+static void send_command(struct vub300_mmc_host *vub300)
+{
+	/* cmd_mutex is held by vub300_cmndwork_thread */
+	struct mmc_command *cmd = vub300->cmd;
+	struct mmc_data *data = vub300->data;
+	int retval;
+	int i;
+	u8 response_type;
+	if (vub300->app_spec) {
+		switch (cmd->opcode) {
+		case 6:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			if (0x00000000 == (0x00000003 & cmd->arg))
+				vub300->bus_width = 1;
+			else if (0x00000002 == (0x00000003 & cmd->arg))
+				vub300->bus_width = 4;
+			else
+				dev_err(&vub300->udev->dev,
+					"unexpected ACMD6 bus_width=%d\n",
+					0x00000003 & cmd->arg);
+			break;
+		case 13:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 22:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 23:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 41:
+			response_type = SDRT_3;
+			vub300->resp_len = 6;
+			break;
+		case 42:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 51:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 55:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		default:
+			vub300->resp_len = 0;
+			cmd->error = -EINVAL;
+			complete(&vub300->command_complete);
+			return;
+		}
+		vub300->app_spec = 0;
+	} else {
+		switch (cmd->opcode) {
+		case 0:
+			response_type = SDRT_NONE;
+			vub300->resp_len = 0;
+			break;
+		case 1:
+			response_type = SDRT_3;
+			vub300->resp_len = 6;
+			break;
+		case 2:
+			response_type = SDRT_2;
+			vub300->resp_len = 17;
+			break;
+		case 3:
+			response_type = SDRT_6;
+			vub300->resp_len = 6;
+			break;
+		case 4:
+			response_type = SDRT_NONE;
+			vub300->resp_len = 0;
+			break;
+		case 5:
+			response_type = SDRT_4;
+			vub300->resp_len = 6;
+			break;
+		case 6:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 7:
+			response_type = SDRT_1B;
+			vub300->resp_len = 6;
+			break;
+		case 8:
+			response_type = SDRT_7;
+			vub300->resp_len = 6;
+			break;
+		case 9:
+			response_type = SDRT_2;
+			vub300->resp_len = 17;
+			break;
+		case 10:
+			response_type = SDRT_2;
+			vub300->resp_len = 17;
+			break;
+		case 12:
+			response_type = SDRT_1B;
+			vub300->resp_len = 6;
+			break;
+		case 13:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 15:
+			response_type = SDRT_NONE;
+			vub300->resp_len = 0;
+			break;
+		case 16:
+			for (i = 0; i < ARRAY_SIZE(vub300->fbs); i++)
+				vub300->fbs[i] = 0xFFFF & cmd->arg;
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 17:
+		case 18:
+		case 24:
+		case 25:
+		case 27:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 28:
+		case 29:
+			response_type = SDRT_1B;
+			vub300->resp_len = 6;
+			break;
+		case 30:
+		case 32:
+		case 33:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 38:
+			response_type = SDRT_1B;
+			vub300->resp_len = 6;
+			break;
+		case 42:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		case 52:
+			response_type = SDRT_5;
+			vub300->resp_len = 6;
+			snoop_block_size_and_bus_width(vub300, cmd->arg);
+			break;
+		case 53:
+			response_type = SDRT_5;
+			vub300->resp_len = 6;
+			break;
+		case 55:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			vub300->app_spec = 1;
+			break;
+		case 56:
+			response_type = SDRT_1;
+			vub300->resp_len = 6;
+			break;
+		default:
+			vub300->resp_len = 0;
+			cmd->error = -EINVAL;
+			complete(&vub300->command_complete);
+			return;
+		}
+	}
+	/*
+	 * it is a shame that we can not use "sizeof(struct sd_command_header)"
+	 * this is because the packet _must_ be padded to 64 bytes
+	 */
+	vub300->cmnd.head.header_size = 20;
+	vub300->cmnd.head.header_type = 0x00;
+	vub300->cmnd.head.port_number = 0; /* "0" means port 1 */
+	vub300->cmnd.head.command_type = 0x00; /* standard read command */
+	vub300->cmnd.head.response_type = response_type;
+	vub300->cmnd.head.command_index = cmd->opcode;
+	vub300->cmnd.head.arguments[0] = cmd->arg >> 24;
+	vub300->cmnd.head.arguments[1] = cmd->arg >> 16;
+	vub300->cmnd.head.arguments[2] = cmd->arg >> 8;
+	vub300->cmnd.head.arguments[3] = cmd->arg >> 0;
+	if (cmd->opcode == 52) {
+		int fn = 0x7 & (cmd->arg >> 28);
+		vub300->cmnd.head.block_count[0] = 0;
+		vub300->cmnd.head.block_count[1] = 0;
+		vub300->cmnd.head.block_size[0] = (vub300->fbs[fn] >> 8) & 0xFF;
+		vub300->cmnd.head.block_size[1] = (vub300->fbs[fn] >> 0) & 0xFF;
+		vub300->cmnd.head.command_type = 0x00;
+		vub300->cmnd.head.transfer_size[0] = 0;
+		vub300->cmnd.head.transfer_size[1] = 0;
+		vub300->cmnd.head.transfer_size[2] = 0;
+		vub300->cmnd.head.transfer_size[3] = 0;
+	} else if (!data) {
+		vub300->cmnd.head.block_count[0] = 0;
+		vub300->cmnd.head.block_count[1] = 0;
+		vub300->cmnd.head.block_size[0] = (vub300->fbs[0] >> 8) & 0xFF;
+		vub300->cmnd.head.block_size[1] = (vub300->fbs[0] >> 0) & 0xFF;
+		vub300->cmnd.head.command_type = 0x00;
+		vub300->cmnd.head.transfer_size[0] = 0;
+		vub300->cmnd.head.transfer_size[1] = 0;
+		vub300->cmnd.head.transfer_size[2] = 0;
+		vub300->cmnd.head.transfer_size[3] = 0;
+	} else if (cmd->opcode == 53) {
+		int fn = 0x7 & (cmd->arg >> 28);
+		if (0x08 & vub300->cmnd.head.arguments[0]) { /* BLOCK MODE */
+			vub300->cmnd.head.block_count[0] =
+				(data->blocks >> 8) & 0xFF;
+			vub300->cmnd.head.block_count[1] =
+				(data->blocks >> 0) & 0xFF;
+			vub300->cmnd.head.block_size[0] =
+				(data->blksz >> 8) & 0xFF;
+			vub300->cmnd.head.block_size[1] =
+				(data->blksz >> 0) & 0xFF;
+		} else {	/* BYTE MODE */
+			vub300->cmnd.head.block_count[0] = 0;
+			vub300->cmnd.head.block_count[1] = 0;
+			vub300->cmnd.head.block_size[0] =
+				(vub300->datasize >> 8) & 0xFF;
+			vub300->cmnd.head.block_size[1] =
+				(vub300->datasize >> 0) & 0xFF;
+		}
+		vub300->cmnd.head.command_type =
+			(MMC_DATA_READ & data->flags) ? 0x00 : 0x80;
+		vub300->cmnd.head.transfer_size[0] =
+			(vub300->datasize >> 24) & 0xFF;
+		vub300->cmnd.head.transfer_size[1] =
+			(vub300->datasize >> 16) & 0xFF;
+		vub300->cmnd.head.transfer_size[2] =
+			(vub300->datasize >> 8) & 0xFF;
+		vub300->cmnd.head.transfer_size[3] =
+			(vub300->datasize >> 0) & 0xFF;
+		if (vub300->datasize < vub300->fbs[fn]) {
+			vub300->cmnd.head.block_count[0] = 0;
+			vub300->cmnd.head.block_count[1] = 0;
+		}
+	} else {
+		vub300->cmnd.head.block_count[0] = (data->blocks >> 8) & 0xFF;
+		vub300->cmnd.head.block_count[1] = (data->blocks >> 0) & 0xFF;
+		vub300->cmnd.head.block_size[0] = (data->blksz >> 8) & 0xFF;
+		vub300->cmnd.head.block_size[1] = (data->blksz >> 0) & 0xFF;
+		vub300->cmnd.head.command_type =
+			(MMC_DATA_READ & data->flags) ? 0x00 : 0x80;
+		vub300->cmnd.head.transfer_size[0] =
+			(vub300->datasize >> 24) & 0xFF;
+		vub300->cmnd.head.transfer_size[1] =
+			(vub300->datasize >> 16) & 0xFF;
+		vub300->cmnd.head.transfer_size[2] =
+			(vub300->datasize >> 8) & 0xFF;
+		vub300->cmnd.head.transfer_size[3] =
+			(vub300->datasize >> 0) & 0xFF;
+		if (vub300->datasize < vub300->fbs[0]) {
+			vub300->cmnd.head.block_count[0] = 0;
+			vub300->cmnd.head.block_count[1] = 0;
+		}
+	}
+	if (vub300->cmnd.head.block_size[0] || vub300->cmnd.head.block_size[1]) {
+		u16 block_size = vub300->cmnd.head.block_size[1] |
+			(vub300->cmnd.head.block_size[0] << 8);
+		u16 block_boundary = FIRMWARE_BLOCK_BOUNDARY -
+			(FIRMWARE_BLOCK_BOUNDARY % block_size);
+		vub300->cmnd.head.block_boundary[0] =
+			(block_boundary >> 8) & 0xFF;
+		vub300->cmnd.head.block_boundary[1] =
+			(block_boundary >> 0) & 0xFF;
+	} else {
+		vub300->cmnd.head.block_boundary[0] = 0;
+		vub300->cmnd.head.block_boundary[1] = 0;
+	}
+	usb_fill_bulk_urb(vub300->command_out_urb, vub300->udev,
+			  usb_sndbulkpipe(vub300->udev, vub300->cmnd_out_ep),
+			  &vub300->cmnd, sizeof(vub300->cmnd),
+			  command_out_completed, vub300);
+	retval = usb_submit_urb(vub300->command_out_urb, GFP_KERNEL);
+	if (retval < 0) {
+		cmd->error = retval;
+		complete(&vub300->command_complete);
+		return;
+	} else {
+		return;
+	}
+}
+
+/*
+ * timer callback runs in atomic mode
+ *       so it cannot call usb_kill_urb()
+ */
+static void vub300_sg_timed_out(unsigned long data)
+{
+	struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)data;
+	vub300->usb_timed_out = 1;
+	usb_sg_cancel(&vub300->sg_request);
+	usb_unlink_urb(vub300->command_out_urb);
+	usb_unlink_urb(vub300->command_res_urb);
+}
+
+static u16 roundup_to_multiple_of_64(u16 number)
+{
+	return 0xFFC0 & (0x3F + number);
+}
+
+/*
+ * this is a separate function to solve the 80 column width restriction
+ */
+static void __download_offload_pseudocode(struct vub300_mmc_host *vub300,
+					  const struct firmware *fw)
+{
+	u8 register_count = 0;
+	u16 ts = 0;
+	u16 interrupt_size = 0;
+	const u8 *data = fw->data;
+	int size = fw->size;
+	u8 c;
+	dev_info(&vub300->udev->dev, "using %s for SDIO offload processing\n",
+		 vub300->vub_name);
+	do {
+		c = *data++;
+	} while (size-- && c); /* skip comment */
+	dev_info(&vub300->udev->dev, "using offload firmware %s %s\n", fw->data,
+		 vub300->vub_name);
+	if (size < 4) {
+		dev_err(&vub300->udev->dev,
+			"corrupt offload pseudocode in firmware %s\n",
+			vub300->vub_name);
+		strncpy(vub300->vub_name, "corrupt offload pseudocode",
+			sizeof(vub300->vub_name));
+		return;
+	}
+	interrupt_size += *data++;
+	size -= 1;
+	interrupt_size <<= 8;
+	interrupt_size += *data++;
+	size -= 1;
+	if (interrupt_size < size) {
+		u16 xfer_length = roundup_to_multiple_of_64(interrupt_size);
+		u8 *xfer_buffer = kmalloc(xfer_length, GFP_KERNEL);
+		if (xfer_buffer) {
+			int retval;
+			memcpy(xfer_buffer, data, interrupt_size);
+			memset(xfer_buffer + interrupt_size, 0,
+			       xfer_length - interrupt_size);
+			size -= interrupt_size;
+			data += interrupt_size;
+			retval =
+				usb_control_msg(vub300->udev,
+						usb_sndctrlpipe(vub300->udev, 0),
+						SET_INTERRUPT_PSEUDOCODE,
+						USB_DIR_OUT | USB_TYPE_VENDOR |
+						USB_RECIP_DEVICE, 0x0000, 0x0000,
+						xfer_buffer, xfer_length, HZ);
+			kfree(xfer_buffer);
+			if (retval < 0) {
+				strncpy(vub300->vub_name,
+					"SDIO pseudocode download failed",
+					sizeof(vub300->vub_name));
+				return;
+			}
+		} else {
+			dev_err(&vub300->udev->dev,
+				"not enough memory for xfer buffer to send"
+				" INTERRUPT_PSEUDOCODE for %s %s\n", fw->data,
+				vub300->vub_name);
+			strncpy(vub300->vub_name,
+				"SDIO interrupt pseudocode download failed",
+				sizeof(vub300->vub_name));
+			return;
+		}
+	} else {
+		dev_err(&vub300->udev->dev,
+			"corrupt interrupt pseudocode in firmware %s %s\n",
+			fw->data, vub300->vub_name);
+		strncpy(vub300->vub_name, "corrupt interrupt pseudocode",
+			sizeof(vub300->vub_name));
+		return;
+	}
+	ts += *data++;
+	size -= 1;
+	ts <<= 8;
+	ts += *data++;
+	size -= 1;
+	if (ts < size) {
+		u16 xfer_length = roundup_to_multiple_of_64(ts);
+		u8 *xfer_buffer = kmalloc(xfer_length, GFP_KERNEL);
+		if (xfer_buffer) {
+			int retval;
+			memcpy(xfer_buffer, data, ts);
+			memset(xfer_buffer + ts, 0,
+			       xfer_length - ts);
+			size -= ts;
+			data += ts;
+			retval =
+				usb_control_msg(vub300->udev,
+						usb_sndctrlpipe(vub300->udev, 0),
+						SET_TRANSFER_PSEUDOCODE,
+						USB_DIR_OUT | USB_TYPE_VENDOR |
+						USB_RECIP_DEVICE, 0x0000, 0x0000,
+						xfer_buffer, xfer_length, HZ);
+			kfree(xfer_buffer);
+			if (retval < 0) {
+				strncpy(vub300->vub_name,
+					"SDIO pseudocode download failed",
+					sizeof(vub300->vub_name));
+				return;
+			}
+		} else {
+			dev_err(&vub300->udev->dev,
+				"not enough memory for xfer buffer to send"
+				" TRANSFER_PSEUDOCODE for %s %s\n", fw->data,
+				vub300->vub_name);
+			strncpy(vub300->vub_name,
+				"SDIO transfer pseudocode download failed",
+				sizeof(vub300->vub_name));
+			return;
+		}
+	} else {
+		dev_err(&vub300->udev->dev,
+			"corrupt transfer pseudocode in firmware %s %s\n",
+			fw->data, vub300->vub_name);
+		strncpy(vub300->vub_name, "corrupt transfer pseudocode",
+			sizeof(vub300->vub_name));
+		return;
+	}
+	register_count += *data++;
+	size -= 1;
+	if (register_count * 4 == size) {
+		int I = vub300->dynamic_register_count = register_count;
+		int i = 0;
+		while (I--) {
+			unsigned int func_num = 0;
+			vub300->sdio_register[i].func_num = *data++;
+			size -= 1;
+			func_num += *data++;
+			size -= 1;
+			func_num <<= 8;
+			func_num += *data++;
+			size -= 1;
+			func_num <<= 8;
+			func_num += *data++;
+			size -= 1;
+			vub300->sdio_register[i].sdio_reg = func_num;
+			vub300->sdio_register[i].activate = 1;
+			vub300->sdio_register[i].prepared = 0;
+			i += 1;
+		}
+		dev_info(&vub300->udev->dev,
+			 "initialized %d dynamic pseudocode registers\n",
+			 vub300->dynamic_register_count);
+		return;
+	} else {
+		dev_err(&vub300->udev->dev,
+			"corrupt dynamic registers in firmware %s\n",
+			vub300->vub_name);
+		strncpy(vub300->vub_name, "corrupt dynamic registers",
+			sizeof(vub300->vub_name));
+		return;
+	}
+}
+
+/*
+ * if the binary containing the EMPTY PseudoCode can not be found
+ * vub300->vub_name is set anyway in order to prevent an automatic retry
+ */
+static void download_offload_pseudocode(struct vub300_mmc_host *vub300)
+{
+	struct mmc_card *card = vub300->mmc->card;
+	int sdio_funcs = card->sdio_funcs;
+	const struct firmware *fw = NULL;
+	int l = snprintf(vub300->vub_name, sizeof(vub300->vub_name),
+			 "vub_%04X%04X", card->cis.vendor, card->cis.device);
+	int n = 0;
+	int retval;
+	for (n = 0; n < sdio_funcs; n++) {
+		struct sdio_func *sf = card->sdio_func[n];
+		l += snprintf(vub300->vub_name + l,
+			      sizeof(vub300->vub_name) - l, "_%04X%04X",
+			      sf->vendor, sf->device);
+	};
+	snprintf(vub300->vub_name + l, sizeof(vub300->vub_name) - l, ".bin");
+	dev_info(&vub300->udev->dev, "requesting offload firmware %s\n",
+		 vub300->vub_name);
+	retval = request_firmware(&fw, vub300->vub_name, &card->dev);
+	if (retval < 0) {
+		strncpy(vub300->vub_name, "vub_default.bin",
+			sizeof(vub300->vub_name));
+		retval = request_firmware(&fw, vub300->vub_name, &card->dev);
+		if (retval < 0) {
+			strncpy(vub300->vub_name,
+				"no SDIO offload firmware found",
+				sizeof(vub300->vub_name));
+		} else {
+			__download_offload_pseudocode(vub300, fw);
+			release_firmware(fw);
+		}
+	} else {
+		__download_offload_pseudocode(vub300, fw);
+		release_firmware(fw);
+	}
+}
+
+static void vub300_usb_bulk_msg_completion(struct urb *urb)
+{				/* urb completion handler - hardirq */
+	complete((struct completion *)urb->context);
+}
+
+static int vub300_usb_bulk_msg(struct vub300_mmc_host *vub300,
+			       unsigned int pipe, void *data, int len,
+			       int *actual_length, int timeout_msecs)
+{
+	/* cmd_mutex is held by vub300_cmndwork_thread */
+	struct usb_device *usb_dev = vub300->udev;
+	struct completion done;
+	int retval;
+	vub300->urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!vub300->urb)
+		return -ENOMEM;
+	usb_fill_bulk_urb(vub300->urb, usb_dev, pipe, data, len,
+			  vub300_usb_bulk_msg_completion, NULL);
+	init_completion(&done);
+	vub300->urb->context = &done;
+	vub300->urb->actual_length = 0;
+	retval = usb_submit_urb(vub300->urb, GFP_KERNEL);
+	if (unlikely(retval))
+		goto out;
+	if (!wait_for_completion_timeout
+	    (&done, msecs_to_jiffies(timeout_msecs))) {
+		retval = -ETIMEDOUT;
+		usb_kill_urb(vub300->urb);
+	} else {
+		retval = vub300->urb->status;
+	}
+out:
+	*actual_length = vub300->urb->actual_length;
+	usb_free_urb(vub300->urb);
+	vub300->urb = NULL;
+	return retval;
+}
+
+static int __command_read_data(struct vub300_mmc_host *vub300,
+			       struct mmc_command *cmd, struct mmc_data *data)
+{
+	/* cmd_mutex is held by vub300_cmndwork_thread */
+	int linear_length = vub300->datasize;
+	int padded_length = vub300->large_usb_packets ?
+		((511 + linear_length) >> 9) << 9 :
+		((63 + linear_length) >> 6) << 6;
+	if ((padded_length == linear_length) || !pad_input_to_usb_pkt) {
+		int result;
+		unsigned pipe;
+		pipe = usb_rcvbulkpipe(vub300->udev, vub300->data_inp_ep);
+		result = usb_sg_init(&vub300->sg_request, vub300->udev,
+				     pipe, 0, data->sg,
+				     data->sg_len, 0, GFP_KERNEL);
+		if (result < 0) {
+			usb_unlink_urb(vub300->command_out_urb);
+			usb_unlink_urb(vub300->command_res_urb);
+			cmd->error = result;
+			data->bytes_xfered = 0;
+			return 0;
+		} else {
+			vub300->sg_transfer_timer.expires =
+				jiffies + msecs_to_jiffies(2000 +
+						  (linear_length / 16384));
+			add_timer(&vub300->sg_transfer_timer);
+			usb_sg_wait(&vub300->sg_request);
+			del_timer(&vub300->sg_transfer_timer);
+			if (vub300->sg_request.status < 0) {
+				cmd->error = vub300->sg_request.status;
+				data->bytes_xfered = 0;
+				return 0;
+			} else {
+				data->bytes_xfered = vub300->datasize;
+				return linear_length;
+			}
+		}
+	} else {
+		u8 *buf = kmalloc(padded_length, GFP_KERNEL);
+		if (buf) {
+			int result;
+			unsigned pipe = usb_rcvbulkpipe(vub300->udev,
+							vub300->data_inp_ep);
+			int actual_length = 0;
+			result = vub300_usb_bulk_msg(vub300, pipe, buf,
+					     padded_length, &actual_length,
+					     2000 + (padded_length / 16384));
+			if (result < 0) {
+				cmd->error = result;
+				data->bytes_xfered = 0;
+				kfree(buf);
+				return 0;
+			} else if (actual_length < linear_length) {
+				cmd->error = -EREMOTEIO;
+				data->bytes_xfered = 0;
+				kfree(buf);
+				return 0;
+			} else {
+				sg_copy_from_buffer(data->sg, data->sg_len, buf,
+						    linear_length);
+				kfree(buf);
+				data->bytes_xfered = vub300->datasize;
+				return linear_length;
+			}
+		} else {
+			cmd->error = -ENOMEM;
+			data->bytes_xfered = 0;
+			return 0;
+		}
+	}
+}
+
+static int __command_write_data(struct vub300_mmc_host *vub300,
+				struct mmc_command *cmd, struct mmc_data *data)
+{
+	/* cmd_mutex is held by vub300_cmndwork_thread */
+	unsigned pipe = usb_sndbulkpipe(vub300->udev, vub300->data_out_ep);
+	int linear_length = vub300->datasize;
+	int modulo_64_length = linear_length & 0x003F;
+	int modulo_512_length = linear_length & 0x01FF;
+	if (linear_length < 64) {
+		int result;
+		int actual_length;
+		sg_copy_to_buffer(data->sg, data->sg_len,
+				  vub300->padded_buffer,
+				  sizeof(vub300->padded_buffer));
+		memset(vub300->padded_buffer + linear_length, 0,
+		       sizeof(vub300->padded_buffer) - linear_length);
+		result = vub300_usb_bulk_msg(vub300, pipe, vub300->padded_buffer,
+					     sizeof(vub300->padded_buffer),
+					     &actual_length, 2000 +
+					     (sizeof(vub300->padded_buffer) /
+					      16384));
+		if (result < 0) {
+			cmd->error = result;
+			data->bytes_xfered = 0;
+		} else {
+			data->bytes_xfered = vub300->datasize;
+		}
+	} else if ((!vub300->large_usb_packets && (0 < modulo_64_length)) ||
+		    (vub300->large_usb_packets && (64 > modulo_512_length))
+		) {		/* don't you just love these work-rounds */
+		int padded_length = ((63 + linear_length) >> 6) << 6;
+		u8 *buf = kmalloc(padded_length, GFP_KERNEL);
+		if (buf) {
+			int result;
+			int actual_length;
+			sg_copy_to_buffer(data->sg, data->sg_len, buf,
+					  padded_length);
+			memset(buf + linear_length, 0,
+			       padded_length - linear_length);
+			result =
+				vub300_usb_bulk_msg(vub300, pipe, buf,
+						    padded_length, &actual_length,
+						    2000 + padded_length / 16384);
+			kfree(buf);
+			if (result < 0) {
+				cmd->error = result;
+				data->bytes_xfered = 0;
+			} else {
+				data->bytes_xfered = vub300->datasize;
+			}
+		} else {
+			cmd->error = -ENOMEM;
+			data->bytes_xfered = 0;
+		}
+	} else {		/* no data padding required */
+		int result;
+		unsigned char buf[64 * 4];
+		sg_copy_to_buffer(data->sg, data->sg_len, buf, sizeof(buf));
+		result = usb_sg_init(&vub300->sg_request, vub300->udev,
+				     pipe, 0, data->sg,
+				     data->sg_len, 0, GFP_KERNEL);
+		if (result < 0) {
+			usb_unlink_urb(vub300->command_out_urb);
+			usb_unlink_urb(vub300->command_res_urb);
+			cmd->error = result;
+			data->bytes_xfered = 0;
+		} else {
+			vub300->sg_transfer_timer.expires =
+				jiffies + msecs_to_jiffies(2000 +
+							   linear_length / 16384);
+			add_timer(&vub300->sg_transfer_timer);
+			usb_sg_wait(&vub300->sg_request);
+			if (cmd->error) {
+				data->bytes_xfered = 0;
+			} else {
+				del_timer(&vub300->sg_transfer_timer);
+				if (vub300->sg_request.status < 0) {
+					cmd->error = vub300->sg_request.status;
+					data->bytes_xfered = 0;
+				} else {
+					data->bytes_xfered = vub300->datasize;
+				}
+			}
+		}
+	}
+	return linear_length;
+}
+
+static void __vub300_command_response(struct vub300_mmc_host *vub300,
+				      struct mmc_command *cmd,
+				      struct mmc_data *data, int data_length)
+{
+	/* cmd_mutex is held by vub300_cmndwork_thread */
+	long respretval;
+	int msec_timeout = 1000 + data_length / 4;
+	respretval =
+		wait_for_completion_timeout(&vub300->command_complete,
+					    msecs_to_jiffies(msec_timeout));
+	if (respretval == 0) { /* TIMED OUT */
+		/* we don't know which of "out" and "res" if any failed */
+		int result;
+		vub300->usb_timed_out = 1;
+		usb_kill_urb(vub300->command_out_urb);
+		usb_kill_urb(vub300->command_res_urb);
+		cmd->error = -ETIMEDOUT;
+		result = usb_lock_device_for_reset(vub300->udev,
+						   vub300->interface);
+		if (result == 0) {
+			result = usb_reset_device(vub300->udev);
+			usb_unlock_device(vub300->udev);
+		}
+	} else if (respretval < 0) {
+		/* we don't know which of "out" and "res" if any failed */
+		usb_kill_urb(vub300->command_out_urb);
+		usb_kill_urb(vub300->command_res_urb);
+		cmd->error = respretval;
+	} else if (cmd->error) {
+		/*
+		 * the error occured sending the command
+		 * or recieving the response
+		 */
+	} else if (vub300->command_out_urb->status) {
+		vub300->usb_transport_fail = vub300->command_out_urb->status;
+		cmd->error = -EPROTO == vub300->command_out_urb->status ?
+			-ESHUTDOWN : vub300->command_out_urb->status;
+	} else if (vub300->command_res_urb->status) {
+		vub300->usb_transport_fail = vub300->command_res_urb->status;
+		cmd->error = -EPROTO == vub300->command_res_urb->status ?
+			-ESHUTDOWN : vub300->command_res_urb->status;
+	} else if (vub300->resp.common.header_type == 0x00) {
+		/*
+		 * the command completed successfully
+		 * and there was no piggybacked data
+		 */
+	} else if (vub300->resp.common.header_type == RESPONSE_ERROR) {
+		cmd->error =
+			vub300_response_error(vub300->resp.error.error_code);
+		if (vub300->data)
+			usb_sg_cancel(&vub300->sg_request);
+	} else if (vub300->resp.common.header_type == RESPONSE_PIGGYBACKED) {
+		int offloaded_data_length =
+			vub300->resp.common.header_size -
+			sizeof(struct sd_register_header);
+		int register_count = offloaded_data_length >> 3;
+		int ri = 0;
+		while (register_count--) {
+			add_offloaded_reg(vub300, &vub300->resp.pig.reg[ri]);
+			ri += 1;
+		}
+		vub300->resp.common.header_size =
+			sizeof(struct sd_register_header);
+		vub300->resp.common.header_type = 0x00;
+		cmd->error = 0;
+	} else if (vub300->resp.common.header_type == RESPONSE_PIG_DISABLED) {
+		int offloaded_data_length =
+			vub300->resp.common.header_size -
+			sizeof(struct sd_register_header);
+		int register_count = offloaded_data_length >> 3;
+		int ri = 0;
+		while (register_count--) {
+			add_offloaded_reg(vub300, &vub300->resp.pig.reg[ri]);
+			ri += 1;
+		}
+		mutex_lock(&vub300->irq_mutex);
+		if (vub300->irqs_queued) {
+			vub300->irqs_queued += 1;
+		} else if (vub300->irq_enabled) {
+			vub300->irqs_queued += 1;
+			vub300_queue_poll_work(vub300, 0);
+		} else {
+			vub300->irqs_queued += 1;
+		}
+		vub300->irq_disabled = 1;
+		mutex_unlock(&vub300->irq_mutex);
+		vub300->resp.common.header_size =
+			sizeof(struct sd_register_header);
+		vub300->resp.common.header_type = 0x00;
+		cmd->error = 0;
+	} else if (vub300->resp.common.header_type == RESPONSE_PIG_ENABLED) {
+		int offloaded_data_length =
+			vub300->resp.common.header_size -
+			sizeof(struct sd_register_header);
+		int register_count = offloaded_data_length >> 3;
+		int ri = 0;
+		while (register_count--) {
+			add_offloaded_reg(vub300, &vub300->resp.pig.reg[ri]);
+			ri += 1;
+		}
+		mutex_lock(&vub300->irq_mutex);
+		if (vub300->irqs_queued) {
+			vub300->irqs_queued += 1;
+		} else if (vub300->irq_enabled) {
+			vub300->irqs_queued += 1;
+			vub300_queue_poll_work(vub300, 0);
+		} else {
+			vub300->irqs_queued += 1;
+		}
+		vub300->irq_disabled = 0;
+		mutex_unlock(&vub300->irq_mutex);
+		vub300->resp.common.header_size =
+			sizeof(struct sd_register_header);
+		vub300->resp.common.header_type = 0x00;
+		cmd->error = 0;
+	} else {
+		cmd->error = -EINVAL;
+	}
+}
+
+static void construct_request_response(struct vub300_mmc_host *vub300,
+				       struct mmc_command *cmd)
+{
+	int resp_len = vub300->resp_len;
+	int less_cmd = (17 == resp_len) ? resp_len : resp_len - 1;
+	int bytes = 3 & less_cmd;
+	int words = less_cmd >> 2;
+	u8 *r = vub300->resp.response.command_response;
+	if (bytes == 3) {
+		cmd->resp[words] = (r[1 + (words << 2)] << 24)
+			| (r[2 + (words << 2)] << 16)
+			| (r[3 + (words << 2)] << 8);
+	} else if (bytes == 2) {
+		cmd->resp[words] = (r[1 + (words << 2)] << 24)
+			| (r[2 + (words << 2)] << 16);
+	} else if (bytes == 1) {
+		cmd->resp[words] = (r[1 + (words << 2)] << 24);
+	}
+	while (words-- > 0) {
+		cmd->resp[words] = (r[1 + (words << 2)] << 24)
+			| (r[2 + (words << 2)] << 16)
+			| (r[3 + (words << 2)] << 8)
+			| (r[4 + (words << 2)] << 0);
+	}
+	if ((cmd->opcode == 53) && (0x000000FF & cmd->resp[0]))
+		cmd->resp[0] &= 0xFFFFFF00;
+}
+
+/* this thread runs only when there is an upper level command req outstanding */
+static void vub300_cmndwork_thread(struct work_struct *work)
+{
+	struct vub300_mmc_host *vub300 =
+		container_of(work, struct vub300_mmc_host, cmndwork);
+	if (!vub300->interface) {
+		kref_put(&vub300->kref, vub300_delete);
+		return;
+	} else {
+		struct mmc_request *req = vub300->req;
+		struct mmc_command *cmd = vub300->cmd;
+		struct mmc_data *data = vub300->data;
+		int data_length;
+		mutex_lock(&vub300->cmd_mutex);
+		init_completion(&vub300->command_complete);
+		if (likely(vub300->vub_name[0]) || !vub300->mmc->card ||
+		    !mmc_card_present(vub300->mmc->card)) {
+			/*
+			 * the name of the EMPTY Pseudo firmware file
+			 * is used as a flag to indicate that the file
+			 * has been already downloaded to the VUB300 chip
+			 */
+		} else if (0 == vub300->mmc->card->sdio_funcs) {
+			strncpy(vub300->vub_name, "SD memory device",
+				sizeof(vub300->vub_name));
+		} else {
+			download_offload_pseudocode(vub300);
+		}
+		send_command(vub300);
+		if (!data)
+			data_length = 0;
+		else if (MMC_DATA_READ & data->flags)
+			data_length = __command_read_data(vub300, cmd, data);
+		else
+			data_length = __command_write_data(vub300, cmd, data);
+		__vub300_command_response(vub300, cmd, data, data_length);
+		vub300->req = NULL;
+		vub300->cmd = NULL;
+		vub300->data = NULL;
+		if (cmd->error) {
+			if (cmd->error == -ENOMEDIUM)
+				check_vub300_port_status(vub300);
+			mutex_unlock(&vub300->cmd_mutex);
+			mmc_request_done(vub300->mmc, req);
+			kref_put(&vub300->kref, vub300_delete);
+			return;
+		} else {
+			construct_request_response(vub300, cmd);
+			vub300->resp_len = 0;
+			mutex_unlock(&vub300->cmd_mutex);
+			kref_put(&vub300->kref, vub300_delete);
+			mmc_request_done(vub300->mmc, req);
+			return;
+		}
+	}
+}
+
+static int examine_cyclic_buffer(struct vub300_mmc_host *vub300,
+				 struct mmc_command *cmd, u8 Function)
+{
+	/* cmd_mutex is held by vub300_mmc_request */
+	u8 cmd0 = 0xFF & (cmd->arg >> 24);
+	u8 cmd1 = 0xFF & (cmd->arg >> 16);
+	u8 cmd2 = 0xFF & (cmd->arg >> 8);
+	u8 cmd3 = 0xFF & (cmd->arg >> 0);
+	int first = MAXREGMASK & vub300->fn[Function].offload_point;
+	struct offload_registers_access *rf = &vub300->fn[Function].reg[first];
+	if (cmd0 == rf->command_byte[0] &&
+	    cmd1 == rf->command_byte[1] &&
+	    cmd2 == rf->command_byte[2] &&
+	    cmd3 == rf->command_byte[3]) {
+		u8 checksum = 0x00;
+		cmd->resp[1] = checksum << 24;
+		cmd->resp[0] = (rf->Respond_Byte[0] << 24)
+			| (rf->Respond_Byte[1] << 16)
+			| (rf->Respond_Byte[2] << 8)
+			| (rf->Respond_Byte[3] << 0);
+		vub300->fn[Function].offload_point += 1;
+		vub300->fn[Function].offload_count -= 1;
+		vub300->total_offload_count -= 1;
+		return 1;
+	} else {
+		int delta = 1;	/* because it does not match the first one */
+		u8 register_count = vub300->fn[Function].offload_count - 1;
+		u32 register_point = vub300->fn[Function].offload_point + 1;
+		while (0 < register_count) {
+			int point = MAXREGMASK & register_point;
+			struct offload_registers_access *r =
+				&vub300->fn[Function].reg[point];
+			if (cmd0 == r->command_byte[0] &&
+			    cmd1 == r->command_byte[1] &&
+			    cmd2 == r->command_byte[2] &&
+			    cmd3 == r->command_byte[3]) {
+				u8 checksum = 0x00;
+				cmd->resp[1] = checksum << 24;
+				cmd->resp[0] = (r->Respond_Byte[0] << 24)
+					| (r->Respond_Byte[1] << 16)
+					| (r->Respond_Byte[2] << 8)
+					| (r->Respond_Byte[3] << 0);
+				vub300->fn[Function].offload_point += delta;
+				vub300->fn[Function].offload_count -= delta;
+				vub300->total_offload_count -= delta;
+				return 1;
+			} else {
+				register_point += 1;
+				register_count -= 1;
+				delta += 1;
+				continue;
+			}
+		}
+		return 0;
+	}
+}
+
+static int satisfy_request_from_offloaded_data(struct vub300_mmc_host *vub300,
+					       struct mmc_command *cmd)
+{
+	/* cmd_mutex is held by vub300_mmc_request */
+	u8 regs = vub300->dynamic_register_count;
+	u8 i = 0;
+	u8 func = FUN(cmd);
+	u32 reg = REG(cmd);
+	while (0 < regs--) {
+		if ((vub300->sdio_register[i].func_num == func) &&
+		    (vub300->sdio_register[i].sdio_reg == reg)) {
+			if (!vub300->sdio_register[i].prepared) {
+				return 0;
+			} else if ((0x80000000 & cmd->arg) == 0x80000000) {
+				/*
+				 * a write to a dynamic register
+				 * nullifies our offloaded value
+				 */
+				vub300->sdio_register[i].prepared = 0;
+				return 0;
+			} else {
+				u8 checksum = 0x00;
+				u8 rsp0 = 0x00;
+				u8 rsp1 = 0x00;
+				u8 rsp2 = vub300->sdio_register[i].response;
+				u8 rsp3 = vub300->sdio_register[i].regvalue;
+				vub300->sdio_register[i].prepared = 0;
+				cmd->resp[1] = checksum << 24;
+				cmd->resp[0] = (rsp0 << 24)
+					| (rsp1 << 16)
+					| (rsp2 << 8)
+					| (rsp3 << 0);
+				return 1;
+			}
+		} else {
+			i += 1;
+			continue;
+		}
+	};
+	if (vub300->total_offload_count == 0)
+		return 0;
+	else if (vub300->fn[func].offload_count == 0)
+		return 0;
+	else
+		return examine_cyclic_buffer(vub300, cmd, func);
+}
+
+static void vub300_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
+{				/* NOT irq */
+	struct mmc_command *cmd = req->cmd;
+	struct vub300_mmc_host *vub300 = mmc_priv(mmc);
+	if (!vub300->interface) {
+		cmd->error = -ESHUTDOWN;
+		mmc_request_done(mmc, req);
+		return;
+	} else {
+		struct mmc_data *data = req->data;
+		if (!vub300->card_powered) {
+			cmd->error = -ENOMEDIUM;
+			mmc_request_done(mmc, req);
+			return;
+		}
+		if (!vub300->card_present) {
+			cmd->error = -ENOMEDIUM;
+			mmc_request_done(mmc, req);
+			return;
+		}
+		if (vub300->usb_transport_fail) {
+			cmd->error = vub300->usb_transport_fail;
+			mmc_request_done(mmc, req);
+			return;
+		}
+		if (!vub300->interface) {
+			cmd->error = -ENODEV;
+			mmc_request_done(mmc, req);
+			return;
+		}
+		kref_get(&vub300->kref);
+		mutex_lock(&vub300->cmd_mutex);
+		mod_timer(&vub300->inactivity_timer, jiffies + HZ);
+		/*
+		 * for performance we have to return immediately
+		 * if the requested data has been offloaded
+		 */
+		if (cmd->opcode == 52 &&
+		    satisfy_request_from_offloaded_data(vub300, cmd)) {
+			cmd->error = 0;
+			mutex_unlock(&vub300->cmd_mutex);
+			kref_put(&vub300->kref, vub300_delete);
+			mmc_request_done(mmc, req);
+			return;
+		} else {
+			vub300->cmd = cmd;
+			vub300->req = req;
+			vub300->data = data;
+			if (data)
+				vub300->datasize = data->blksz * data->blocks;
+			else
+				vub300->datasize = 0;
+			vub300_queue_cmnd_work(vub300);
+			mutex_unlock(&vub300->cmd_mutex);
+			kref_put(&vub300->kref, vub300_delete);
+			/*
+			 * the kernel lock diagnostics complain
+			 * if the cmd_mutex * is "passed on"
+			 * to the cmndwork thread,
+			 * so we must release it now
+			 * and re-acquire it in the cmndwork thread
+			 */
+		}
+	}
+}
+
+static void __set_clock_speed(struct vub300_mmc_host *vub300, u8 buf[8],
+			      struct mmc_ios *ios)
+{
+	int buf_array_size = 8; /* ARRAY_SIZE(buf) does not work !!! */
+	int retval;
+	u32 kHzClock;
+	if (ios->clock >= 48000000)
+		kHzClock = 48000;
+	else if (ios->clock >= 24000000)
+		kHzClock = 24000;
+	else if (ios->clock >= 20000000)
+		kHzClock = 20000;
+	else if (ios->clock >= 15000000)
+		kHzClock = 15000;
+	else if (ios->clock >= 200000)
+		kHzClock = 200;
+	else
+		kHzClock = 0;
+	{
+		int i;
+		u64 c = kHzClock;
+		for (i = 0; i < buf_array_size; i++) {
+			buf[i] = c;
+			c >>= 8;
+		}
+	}
+	retval =
+		usb_control_msg(vub300->udev, usb_sndctrlpipe(vub300->udev, 0),
+				SET_CLOCK_SPEED,
+				USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				0x00, 0x00, buf, buf_array_size, HZ);
+	if (retval != 8) {
+		dev_err(&vub300->udev->dev, "SET_CLOCK_SPEED"
+			" %dkHz failed with retval=%d\n", kHzClock, retval);
+	} else {
+		dev_dbg(&vub300->udev->dev, "SET_CLOCK_SPEED"
+			" %dkHz\n", kHzClock);
+	}
+}
+
+static void vub300_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = mmc_priv(mmc);
+	if (!vub300->interface)
+		return;
+	kref_get(&vub300->kref);
+	mutex_lock(&vub300->cmd_mutex);
+	if ((ios->power_mode == MMC_POWER_OFF) && vub300->card_powered) {
+		vub300->card_powered = 0;
+		usb_control_msg(vub300->udev, usb_sndctrlpipe(vub300->udev, 0),
+				SET_SD_POWER,
+				USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				0x0000, 0x0000, NULL, 0, HZ);
+		/* must wait for the VUB300 u-proc to boot up */
+		msleep(600);
+	} else if ((ios->power_mode == MMC_POWER_UP) && !vub300->card_powered) {
+		usb_control_msg(vub300->udev, usb_sndctrlpipe(vub300->udev, 0),
+				SET_SD_POWER,
+				USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				0x0001, 0x0000, NULL, 0, HZ);
+		msleep(600);
+		vub300->card_powered = 1;
+	} else if (ios->power_mode == MMC_POWER_ON) {
+		u8 *buf = kmalloc(8, GFP_KERNEL);
+		if (buf) {
+			__set_clock_speed(vub300, buf, ios);
+			kfree(buf);
+		}
+	} else {
+		/* this should mean no change of state */
+	}
+	mutex_unlock(&vub300->cmd_mutex);
+	kref_put(&vub300->kref, vub300_delete);
+}
+
+static int vub300_mmc_get_ro(struct mmc_host *mmc)
+{
+	struct vub300_mmc_host *vub300 = mmc_priv(mmc);
+	return vub300->read_only;
+}
+
+static void vub300_enable_sdio_irq(struct mmc_host *mmc, int enable)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = mmc_priv(mmc);
+	if (!vub300->interface)
+		return;
+	kref_get(&vub300->kref);
+	if (enable) {
+		mutex_lock(&vub300->irq_mutex);
+		if (vub300->irqs_queued) {
+			vub300->irqs_queued -= 1;
+			mmc_signal_sdio_irq(vub300->mmc);
+		} else if (vub300->irq_disabled) {
+			vub300->irq_disabled = 0;
+			vub300->irq_enabled = 1;
+			vub300_queue_poll_work(vub300, 0);
+		} else if (vub300->irq_enabled) {
+			/* this should not happen, so we will just ignore it */
+		} else {
+			vub300->irq_enabled = 1;
+			vub300_queue_poll_work(vub300, 0);
+		}
+		mutex_unlock(&vub300->irq_mutex);
+	} else {
+		vub300->irq_enabled = 0;
+	}
+	kref_put(&vub300->kref, vub300_delete);
+}
+
+void vub300_init_card(struct mmc_host *mmc, struct mmc_card *card)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = mmc_priv(mmc);
+	dev_info(&vub300->udev->dev, "NO host QUIRKS for this card\n");
+}
+
+static struct mmc_host_ops vub300_mmc_ops = {
+	.request = vub300_mmc_request,
+	.set_ios = vub300_mmc_set_ios,
+	.get_ro = vub300_mmc_get_ro,
+	.enable_sdio_irq = vub300_enable_sdio_irq,
+	.init_card = vub300_init_card,
+};
+
+static int vub300_probe(struct usb_interface *interface,
+			const struct usb_device_id *id)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = NULL;
+	struct usb_host_interface *iface_desc;
+	struct usb_device *udev = usb_get_dev(interface_to_usbdev(interface));
+	int i;
+	int retval = -ENOMEM;
+	struct urb *command_out_urb;
+	struct urb *command_res_urb;
+	struct mmc_host *mmc;
+	char manufacturer[48];
+	char product[32];
+	char serial_number[32];
+	usb_string(udev, udev->descriptor.iManufacturer, manufacturer,
+		   sizeof(manufacturer));
+	usb_string(udev, udev->descriptor.iProduct, product, sizeof(product));
+	usb_string(udev, udev->descriptor.iSerialNumber, serial_number,
+		   sizeof(serial_number));
+	dev_info(&udev->dev, "probing VID:PID(%04X:%04X) %s %s %s\n",
+		 udev->descriptor.idVendor, udev->descriptor.idProduct,
+		 manufacturer, product, serial_number);
+	command_out_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!command_out_urb) {
+		retval = -ENOMEM;
+		dev_err(&vub300->udev->dev,
+			"not enough memory for the command_out_urb\n");
+		goto error0;
+	}
+	command_res_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!command_res_urb) {
+		retval = -ENOMEM;
+		dev_err(&vub300->udev->dev,
+			"not enough memory for the command_res_urb\n");
+		goto error1;
+	}
+	/* this also allocates memory for our VUB300 mmc host device */
+	mmc = mmc_alloc_host(sizeof(struct vub300_mmc_host), &udev->dev);
+	if (!mmc) {
+		retval = -ENOMEM;
+		dev_err(&vub300->udev->dev,
+			"not enough memory for the mmc_host\n");
+		goto error4;
+	}
+	/* MMC core transfer sizes tunable parameters */
+	mmc->caps = 0;
+	if (!force_1_bit_data_xfers)
+		mmc->caps |= MMC_CAP_4_BIT_DATA;
+	if (!force_polling_for_irqs)
+		mmc->caps |= MMC_CAP_SDIO_IRQ;
+	mmc->caps &= ~MMC_CAP_NEEDS_POLL;
+	/*
+	 * MMC_CAP_NEEDS_POLL causes core.c:mmc_rescan() to poll
+	 * for devices which results in spurious CMD7's being
+	 * issued which stops some SDIO cards from working
+	 */
+	if (limit_speed_to_24_MHz) {
+		mmc->caps |= MMC_CAP_MMC_HIGHSPEED;
+		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
+		mmc->f_max = 24000000;
+		dev_info(&udev->dev, "limiting SDIO speed to 24_MHz\n");
+	} else {
+		mmc->caps |= MMC_CAP_MMC_HIGHSPEED;
+		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
+		mmc->f_max = 48000000;
+	}
+	mmc->f_min = 200000;
+	mmc->max_blk_count = 511;
+	mmc->max_blk_size = 512;
+	mmc->max_segs = 128;
+	if (force_max_req_size)
+		mmc->max_req_size = force_max_req_size * 1024;
+	else
+		mmc->max_req_size = 64 * 1024;
+	mmc->max_seg_size = mmc->max_req_size;
+	mmc->ocr_avail = 0;
+	mmc->ocr_avail |= MMC_VDD_165_195;
+	mmc->ocr_avail |= MMC_VDD_20_21;
+	mmc->ocr_avail |= MMC_VDD_21_22;
+	mmc->ocr_avail |= MMC_VDD_22_23;
+	mmc->ocr_avail |= MMC_VDD_23_24;
+	mmc->ocr_avail |= MMC_VDD_24_25;
+	mmc->ocr_avail |= MMC_VDD_25_26;
+	mmc->ocr_avail |= MMC_VDD_26_27;
+	mmc->ocr_avail |= MMC_VDD_27_28;
+	mmc->ocr_avail |= MMC_VDD_28_29;
+	mmc->ocr_avail |= MMC_VDD_29_30;
+	mmc->ocr_avail |= MMC_VDD_30_31;
+	mmc->ocr_avail |= MMC_VDD_31_32;
+	mmc->ocr_avail |= MMC_VDD_32_33;
+	mmc->ocr_avail |= MMC_VDD_33_34;
+	mmc->ocr_avail |= MMC_VDD_34_35;
+	mmc->ocr_avail |= MMC_VDD_35_36;
+	mmc->ops = &vub300_mmc_ops;
+	vub300 = mmc_priv(mmc);
+	vub300->mmc = mmc;
+	vub300->card_powered = 0;
+	vub300->bus_width = 0;
+	vub300->cmnd.head.block_size[0] = 0x00;
+	vub300->cmnd.head.block_size[1] = 0x00;
+	vub300->app_spec = 0;
+	mutex_init(&vub300->cmd_mutex);
+	mutex_init(&vub300->irq_mutex);
+	vub300->command_out_urb = command_out_urb;
+	vub300->command_res_urb = command_res_urb;
+	vub300->usb_timed_out = 0;
+	vub300->dynamic_register_count = 0;
+
+	for (i = 0; i < ARRAY_SIZE(vub300->fn); i++) {
+		vub300->fn[i].offload_point = 0;
+		vub300->fn[i].offload_count = 0;
+	}
+
+	vub300->total_offload_count = 0;
+	vub300->irq_enabled = 0;
+	vub300->irq_disabled = 0;
+	vub300->irqs_queued = 0;
+
+	for (i = 0; i < ARRAY_SIZE(vub300->sdio_register); i++)
+		vub300->sdio_register[i++].activate = 0;
+
+	vub300->udev = udev;
+	vub300->interface = interface;
+	vub300->cmnd_res_ep = 0;
+	vub300->cmnd_out_ep = 0;
+	vub300->data_inp_ep = 0;
+	vub300->data_out_ep = 0;
+
+	for (i = 0; i < ARRAY_SIZE(vub300->fbs); i++)
+		vub300->fbs[i] = 512;
+
+	/*
+	 *      set up the endpoint information
+	 *
+	 * use the first pair of bulk-in and bulk-out
+	 *     endpoints for Command/Response+Interrupt
+	 *
+	 * use the second pair of bulk-in and bulk-out
+	 *     endpoints for Data In/Out
+	 */
+	vub300->large_usb_packets = 0;
+	iface_desc = interface->cur_altsetting;
+	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+		struct usb_endpoint_descriptor *endpoint =
+			&iface_desc->endpoint[i].desc;
+		dev_info(&vub300->udev->dev,
+			 "vub300 testing %s EndPoint(%d) %02X\n",
+			 usb_endpoint_is_bulk_in(endpoint) ? "BULK IN" :
+			 usb_endpoint_is_bulk_out(endpoint) ? "BULK OUT" :
+			 "UNKNOWN", i, endpoint->bEndpointAddress);
+		if (endpoint->wMaxPacketSize > 64)
+			vub300->large_usb_packets = 1;
+		if (usb_endpoint_is_bulk_in(endpoint)) {
+			if (!vub300->cmnd_res_ep) {
+				vub300->cmnd_res_ep =
+					endpoint->bEndpointAddress;
+			} else if (!vub300->data_inp_ep) {
+				vub300->data_inp_ep =
+					endpoint->bEndpointAddress;
+			} else {
+				dev_warn(&vub300->udev->dev,
+					 "ignoring"
+					 " unexpected bulk_in endpoint");
+			}
+		} else if (usb_endpoint_is_bulk_out(endpoint)) {
+			if (!vub300->cmnd_out_ep) {
+				vub300->cmnd_out_ep =
+					endpoint->bEndpointAddress;
+			} else if (!vub300->data_out_ep) {
+				vub300->data_out_ep =
+					endpoint->bEndpointAddress;
+			} else {
+				dev_warn(&vub300->udev->dev,
+					 "ignoring"
+					 " unexpected bulk_out endpoint");
+			}
+		} else {
+			dev_warn(&vub300->udev->dev,
+				 "vub300 ignoring EndPoint(%d) %02X", i,
+				 endpoint->bEndpointAddress);
+		}
+	}
+	if (vub300->cmnd_res_ep && vub300->cmnd_out_ep &&
+	    vub300->data_inp_ep && vub300->data_out_ep) {
+		dev_info(&vub300->udev->dev,
+			 "vub300 %s packets"
+			 " using EndPoints %02X %02X %02X %02X\n",
+			 vub300->large_usb_packets ? "LARGE" : "SMALL",
+			 vub300->cmnd_out_ep, vub300->cmnd_res_ep,
+			 vub300->data_out_ep, vub300->data_inp_ep);
+		/* we have the expected EndPoints */
+	} else {
+		dev_err(&vub300->udev->dev,
+		    "Could not find two sets of bulk-in/out endpoint pairs\n");
+		retval = -EINVAL;
+		goto error5;
+	}
+	retval =
+		usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
+				GET_HC_INF0,
+				USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				0x0000, 0x0000, &vub300->hc_info,
+				sizeof(vub300->hc_info), HZ);
+	if (retval < 0)
+		goto error5;
+	retval =
+		usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
+				SET_ROM_WAIT_STATES,
+				USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				firmware_rom_wait_states, 0x0000, NULL, 0, HZ);
+	if (retval < 0)
+		goto error5;
+	dev_info(&vub300->udev->dev,
+		 "operating_mode = %s %s %d MHz %s %d byte USB packets\n",
+		 (mmc->caps & MMC_CAP_SDIO_IRQ) ? "IRQs" : "POLL",
+		 (mmc->caps & MMC_CAP_4_BIT_DATA) ? "4-bit" : "1-bit",
+		 mmc->f_max / 1000000,
+		 pad_input_to_usb_pkt ? "padding input data to" : "with",
+		 vub300->large_usb_packets ? 512 : 64);
+	retval =
+		usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
+				GET_SYSTEM_PORT_STATUS,
+				USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+				0x0000, 0x0000, &vub300->system_port_status,
+				sizeof(vub300->system_port_status), HZ);
+	if (retval < 0) {
+		goto error4;
+	} else if (sizeof(vub300->system_port_status) == retval) {
+		vub300->card_present =
+			(0x0001 & vub300->system_port_status.port_flags) ? 1 : 0;
+		vub300->read_only =
+			(0x0010 & vub300->system_port_status.port_flags) ? 1 : 0;
+	} else {
+		goto error4;
+	}
+	usb_set_intfdata(interface, vub300);
+	INIT_DELAYED_WORK(&vub300->pollwork, vub300_pollwork_thread);
+	INIT_WORK(&vub300->cmndwork, vub300_cmndwork_thread);
+	INIT_WORK(&vub300->deadwork, vub300_deadwork_thread);
+	kref_init(&vub300->kref);
+	init_timer(&vub300->sg_transfer_timer);
+	vub300->sg_transfer_timer.data = (unsigned long)vub300;
+	vub300->sg_transfer_timer.function = vub300_sg_timed_out;
+	kref_get(&vub300->kref);
+	init_timer(&vub300->inactivity_timer);
+	vub300->inactivity_timer.data = (unsigned long)vub300;
+	vub300->inactivity_timer.function = vub300_inactivity_timer_expired;
+	vub300->inactivity_timer.expires = jiffies + HZ;
+	add_timer(&vub300->inactivity_timer);
+	if (vub300->card_present)
+		dev_info(&vub300->udev->dev,
+			 "USB vub300 remote SDIO host controller[%d]"
+			 "connected with SD/SDIO card inserted\n",
+			 interface_to_InterfaceNumber(interface));
+	else
+		dev_info(&vub300->udev->dev,
+			 "USB vub300 remote SDIO host controller[%d]"
+			 "connected with no SD/SDIO card inserted\n",
+			 interface_to_InterfaceNumber(interface));
+	mmc_add_host(mmc);
+	return 0;
+error5:
+	mmc_free_host(mmc);
+	/*
+	 * and hence also frees vub300
+	 * which is contained at the end of struct mmc
+	 */
+error4:
+	usb_free_urb(command_out_urb);
+error1:
+	usb_free_urb(command_res_urb);
+error0:
+	return retval;
+}
+
+static void vub300_disconnect(struct usb_interface *interface)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = usb_get_intfdata(interface);
+	if (!vub300 || !vub300->mmc) {
+		return;
+	} else {
+		struct mmc_host *mmc = vub300->mmc;
+		if (!vub300->mmc) {
+			return;
+		} else {
+			int ifnum = interface_to_InterfaceNumber(interface);
+			usb_set_intfdata(interface, NULL);
+			/* prevent more I/O from starting */
+			vub300->interface = NULL;
+			kref_put(&vub300->kref, vub300_delete);
+			mmc_remove_host(mmc);
+			pr_info("USB vub300 remote SDIO host controller[%d]"
+				" now disconnected", ifnum);
+			return;
+		}
+	}
+}
+
+#ifdef CONFIG_PM
+static int vub300_suspend(struct usb_interface *intf, pm_message_t message)
+{
+	struct vub300_mmc_host *vub300 = usb_get_intfdata(intf);
+	if (!vub300 || !vub300->mmc) {
+		return 0;
+	} else {
+		struct mmc_host *mmc = vub300->mmc;
+		mmc_suspend_host(mmc);
+		return 0;
+	}
+}
+
+static int vub300_resume(struct usb_interface *intf)
+{
+	struct vub300_mmc_host *vub300 = usb_get_intfdata(intf);
+	if (!vub300 || !vub300->mmc) {
+		return 0;
+	} else {
+		struct mmc_host *mmc = vub300->mmc;
+		mmc_resume_host(mmc);
+		return 0;
+	}
+}
+#else
+#define vub300_suspend NULL
+#define vub300_resume NULL
+#endif
+static int vub300_pre_reset(struct usb_interface *intf)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = usb_get_intfdata(intf);
+	mutex_lock(&vub300->cmd_mutex);
+	return 0;
+}
+
+static int vub300_post_reset(struct usb_interface *intf)
+{				/* NOT irq */
+	struct vub300_mmc_host *vub300 = usb_get_intfdata(intf);
+	/* we are sure no URBs are active - no locking needed */
+	vub300->errors = -EPIPE;
+	mutex_unlock(&vub300->cmd_mutex);
+	return 0;
+}
+
+static struct usb_driver vub300_driver = {
+	.name = "vub300",
+	.probe = vub300_probe,
+	.disconnect = vub300_disconnect,
+	.suspend = vub300_suspend,
+	.resume = vub300_resume,
+	.pre_reset = vub300_pre_reset,
+	.post_reset = vub300_post_reset,
+	.id_table = vub300_table,
+	.supports_autosuspend = 1,
+};
+
+static int __init vub300_init(void)
+{				/* NOT irq */
+	int result;
+
+	pr_info("VUB300 Driver rom wait states = %02X irqpoll timeout = %04X",
+		firmware_rom_wait_states, 0x0FFFF & firmware_irqpoll_timeout);
+	cmndworkqueue = create_singlethread_workqueue("kvub300c");
+	if (!cmndworkqueue) {
+		pr_err("not enough memory for the REQUEST workqueue");
+		result = -ENOMEM;
+		goto out1;
+	}
+	pollworkqueue = create_singlethread_workqueue("kvub300p");
+	if (!pollworkqueue) {
+		pr_err("not enough memory for the IRQPOLL workqueue");
+		result = -ENOMEM;
+		goto out2;
+	}
+	deadworkqueue = create_singlethread_workqueue("kvub300d");
+	if (!deadworkqueue) {
+		pr_err("not enough memory for the EXPIRED workqueue");
+		result = -ENOMEM;
+		goto out3;
+	}
+	result = usb_register(&vub300_driver);
+	if (result) {
+		pr_err("usb_register failed. Error number %d", result);
+		goto out4;
+	}
+	return 0;
+out4:
+	destroy_workqueue(deadworkqueue);
+out3:
+	destroy_workqueue(pollworkqueue);
+out2:
+	destroy_workqueue(cmndworkqueue);
+out1:
+	return result;
+}
+
+static void __exit vub300_exit(void)
+{
+	usb_deregister(&vub300_driver);
+	flush_workqueue(cmndworkqueue);
+	flush_workqueue(pollworkqueue);
+	flush_workqueue(deadworkqueue);
+	destroy_workqueue(cmndworkqueue);
+	destroy_workqueue(pollworkqueue);
+	destroy_workqueue(deadworkqueue);
+}
+
+module_init(vub300_init);
+module_exit(vub300_exit);
+
+MODULE_AUTHOR("Tony Olech <tony.olech@elandigitalsystems.com>");
+MODULE_DESCRIPTION("VUB300 USB to SD/MMC/SDIO adapter driver");
+MODULE_LICENSE("GPL");