[deliverable/linux.git] / drivers / usb / gadget / storage_common.c

/*
 * storage_common.c -- Common definitions for mass storage functionality
 *
 * Copyright (C) 2003-2008 Alan Stern
 * Copyeight (C) 2009 Samsung Electronics
 * Author: Michal Nazarewicz (m.nazarewicz@samsung.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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


/*
 * This file requires the following identifiers used in USB strings to
 * be defined (each of type pointer to char):
 *  - fsg_string_manufacturer -- name of the manufacturer
 *  - fsg_string_product      -- name of the product
 *  - fsg_string_serial       -- product's serial
 *  - fsg_string_config       -- name of the configuration
 *  - fsg_string_interface    -- name of the interface
 * The first four are only needed when FSG_DESCRIPTORS_DEVICE_STRINGS
 * macro is defined prior to including this file.
 */


#include <asm/unaligned.h>


/*-------------------------------------------------------------------------*/


#ifndef DEBUG
#undef VERBOSE_DEBUG
#undef DUMP_MSGS
#endif /* !DEBUG */

#ifdef VERBOSE_DEBUG
#define VLDBG	LDBG
#else
#define VLDBG(lun, fmt, args...) do { } while (0)
#endif /* VERBOSE_DEBUG */

#define LDBG(lun, fmt, args...)   dev_dbg (&(lun)->dev, fmt, ## args)
#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
#define LWARN(lun, fmt, args...)  dev_warn(&(lun)->dev, fmt, ## args)
#define LINFO(lun, fmt, args...)  dev_info(&(lun)->dev, fmt, ## args)

#define DBG(d, fmt, args...)      dev_dbg (&(d)->gadget->dev, fmt, ## args)
#define VDBG(d, fmt, args...)     dev_vdbg(&(d)->gadget->dev, fmt, ## args)
#define ERROR(d, fmt, args...)    dev_err (&(d)->gadget->dev, fmt, ## args)
#define WARNING(d, fmt, args...)  dev_warn(&(d)->gadget->dev, fmt, ## args)
#define INFO(d, fmt, args...)     dev_info(&(d)->gadget->dev, fmt, ## args)


#ifdef DUMP_MSGS

#  define dump_msg(fsg, /* const char * */ label,			\
		 /* const u8 * */ buf, /* unsigned */ length) do {	\
	if (length < 512) {						\
		DBG(fsg, "%s, length %u:\n", label, length);		\
		print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,	\
			       16, 1, buf, length, 0);			\
	}								\
} while (0)

#  define dump_cdb(fsg) do { } while (0)

#else

#  define dump_msg(fsg, /* const char * */ label, \
		 /* const u8 * */ buf, /* unsigned */ length) do { } while (0)

#  ifdef VERBOSE_DEBUG

#define dump_cdb(fsg)							\
	print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE,	\
		       16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0)		\

#  else

#    define dump_cdb(fsg) do { } while (0)

#  endif /* VERBOSE_DEBUG */

#endif /* DUMP_MSGS */


/*-------------------------------------------------------------------------*/

/* SCSI device types */
#define TYPE_DISK	0x00
#define TYPE_CDROM	0x05

/* USB protocol value = the transport method */
#define USB_PR_CBI	0x00		// Control/Bulk/Interrupt
#define USB_PR_CB	0x01		// Control/Bulk w/o interrupt
#define USB_PR_BULK	0x50		// Bulk-only

/* USB subclass value = the protocol encapsulation */
#define USB_SC_RBC	0x01		// Reduced Block Commands (flash)
#define USB_SC_8020	0x02		// SFF-8020i, MMC-2, ATAPI (CD-ROM)
#define USB_SC_QIC	0x03		// QIC-157 (tape)
#define USB_SC_UFI	0x04		// UFI (floppy)
#define USB_SC_8070	0x05		// SFF-8070i (removable)
#define USB_SC_SCSI	0x06		// Transparent SCSI

/* Bulk-only data structures */

/* Command Block Wrapper */
struct fsg_bulk_cb_wrap {
	__le32	Signature;		// Contains 'USBC'
	u32	Tag;			// Unique per command id
	__le32	DataTransferLength;	// Size of the data
	u8	Flags;			// Direction in bit 7
	u8	Lun;			// LUN (normally 0)
	u8	Length;			// Of the CDB, <= MAX_COMMAND_SIZE
	u8	CDB[16];		// Command Data Block
};

#define USB_BULK_CB_WRAP_LEN	31
#define USB_BULK_CB_SIG		0x43425355	// Spells out USBC
#define USB_BULK_IN_FLAG	0x80

/* Command Status Wrapper */
struct bulk_cs_wrap {
	__le32	Signature;		// Should = 'USBS'
	u32	Tag;			// Same as original command
	__le32	Residue;		// Amount not transferred
	u8	Status;			// See below
};

#define USB_BULK_CS_WRAP_LEN	13
#define USB_BULK_CS_SIG		0x53425355	// Spells out 'USBS'
#define USB_STATUS_PASS		0
#define USB_STATUS_FAIL		1
#define USB_STATUS_PHASE_ERROR	2

/* Bulk-only class specific requests */
#define USB_BULK_RESET_REQUEST		0xff
#define USB_BULK_GET_MAX_LUN_REQUEST	0xfe


/* CBI Interrupt data structure */
struct interrupt_data {
	u8	bType;
	u8	bValue;
};

#define CBI_INTERRUPT_DATA_LEN		2

/* CBI Accept Device-Specific Command request */
#define USB_CBI_ADSC_REQUEST		0x00


#define MAX_COMMAND_SIZE	16	// Length of a SCSI Command Data Block

/* SCSI commands that we recognize */
#define SC_FORMAT_UNIT			0x04
#define SC_INQUIRY			0x12
#define SC_MODE_SELECT_6		0x15
#define SC_MODE_SELECT_10		0x55
#define SC_MODE_SENSE_6			0x1a
#define SC_MODE_SENSE_10		0x5a
#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL	0x1e
#define SC_READ_6			0x08
#define SC_READ_10			0x28
#define SC_READ_12			0xa8
#define SC_READ_CAPACITY		0x25
#define SC_READ_FORMAT_CAPACITIES	0x23
#define SC_READ_HEADER			0x44
#define SC_READ_TOC			0x43
#define SC_RELEASE			0x17
#define SC_REQUEST_SENSE		0x03
#define SC_RESERVE			0x16
#define SC_SEND_DIAGNOSTIC		0x1d
#define SC_START_STOP_UNIT		0x1b
#define SC_SYNCHRONIZE_CACHE		0x35
#define SC_TEST_UNIT_READY		0x00
#define SC_VERIFY			0x2f
#define SC_WRITE_6			0x0a
#define SC_WRITE_10			0x2a
#define SC_WRITE_12			0xaa

/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
#define SS_NO_SENSE				0
#define SS_COMMUNICATION_FAILURE		0x040800
#define SS_INVALID_COMMAND			0x052000
#define SS_INVALID_FIELD_IN_CDB			0x052400
#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE	0x052100
#define SS_LOGICAL_UNIT_NOT_SUPPORTED		0x052500
#define SS_MEDIUM_NOT_PRESENT			0x023a00
#define SS_MEDIUM_REMOVAL_PREVENTED		0x055302
#define SS_NOT_READY_TO_READY_TRANSITION	0x062800
#define SS_RESET_OCCURRED			0x062900
#define SS_SAVING_PARAMETERS_NOT_SUPPORTED	0x053900
#define SS_UNRECOVERED_READ_ERROR		0x031100
#define SS_WRITE_ERROR				0x030c02
#define SS_WRITE_PROTECTED			0x072700

#define SK(x)		((u8) ((x) >> 16))	// Sense Key byte, etc.
#define ASC(x)		((u8) ((x) >> 8))
#define ASCQ(x)		((u8) (x))


/*-------------------------------------------------------------------------*/


struct fsg_lun {
	struct file	*filp;
	loff_t		file_length;
	loff_t		num_sectors;

	unsigned int	ro : 1;
	unsigned int	prevent_medium_removal : 1;
	unsigned int	registered : 1;
	unsigned int	info_valid : 1;

	u32		sense_data;
	u32		sense_data_info;
	u32		unit_attention_data;

	struct device	dev;
};

#define fsg_lun_is_open(curlun)	((curlun)->filp != NULL)

static struct fsg_lun *fsg_lun_from_dev(struct device *dev)
{
	return container_of(dev, struct fsg_lun, dev);
}


/* Big enough to hold our biggest descriptor */
#define EP0_BUFSIZE	256
#define DELAYED_STATUS	(EP0_BUFSIZE + 999)	// An impossibly large value

/* Number of buffers we will use.  2 is enough for double-buffering */
#define FSG_NUM_BUFFERS	2

enum fsg_buffer_state {
	BUF_STATE_EMPTY = 0,
	BUF_STATE_FULL,
	BUF_STATE_BUSY
};

struct fsg_buffhd {
	void				*buf;
	enum fsg_buffer_state		state;
	struct fsg_buffhd		*next;

	/* The NetChip 2280 is faster, and handles some protocol faults
	 * better, if we don't submit any short bulk-out read requests.
	 * So we will record the intended request length here. */
	unsigned int			bulk_out_intended_length;

	struct usb_request		*inreq;
	int				inreq_busy;
	struct usb_request		*outreq;
	int				outreq_busy;
};

enum fsg_state {
	FSG_STATE_COMMAND_PHASE = -10,		// This one isn't used anywhere
	FSG_STATE_DATA_PHASE,
	FSG_STATE_STATUS_PHASE,

	FSG_STATE_IDLE = 0,
	FSG_STATE_ABORT_BULK_OUT,
	FSG_STATE_RESET,
	FSG_STATE_INTERFACE_CHANGE,
	FSG_STATE_CONFIG_CHANGE,
	FSG_STATE_DISCONNECT,
	FSG_STATE_EXIT,
	FSG_STATE_TERMINATED
};

enum data_direction {
	DATA_DIR_UNKNOWN = 0,
	DATA_DIR_FROM_HOST,
	DATA_DIR_TO_HOST,
	DATA_DIR_NONE
};


/*-------------------------------------------------------------------------*/


static inline u32 get_unaligned_be24(u8 *buf)
{
	return 0xffffff & (u32) get_unaligned_be32(buf - 1);
}


/*-------------------------------------------------------------------------*/


enum {
	FSG_STRING_MANUFACTURER	= 1,
	FSG_STRING_PRODUCT,
	FSG_STRING_SERIAL,
	FSG_STRING_CONFIG,
	FSG_STRING_INTERFACE
};


static struct usb_otg_descriptor
fsg_otg_desc = {
	.bLength =		sizeof fsg_otg_desc,
	.bDescriptorType =	USB_DT_OTG,

	.bmAttributes =		USB_OTG_SRP,
};

/* There is only one interface. */

static struct usb_interface_descriptor
fsg_intf_desc = {
	.bLength =		sizeof fsg_intf_desc,
	.bDescriptorType =	USB_DT_INTERFACE,

	.bNumEndpoints =	2,		// Adjusted during fsg_bind()
	.bInterfaceClass =	USB_CLASS_MASS_STORAGE,
	.bInterfaceSubClass =	USB_SC_SCSI,	// Adjusted during fsg_bind()
	.bInterfaceProtocol =	USB_PR_BULK,	// Adjusted during fsg_bind()
	.iInterface =		FSG_STRING_INTERFACE,
};

/* Three full-speed endpoint descriptors: bulk-in, bulk-out,
 * and interrupt-in. */

static struct usb_endpoint_descriptor
fsg_fs_bulk_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	/* wMaxPacketSize set by autoconfiguration */
};

static struct usb_endpoint_descriptor
fsg_fs_bulk_out_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_OUT,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	/* wMaxPacketSize set by autoconfiguration */
};

static struct usb_endpoint_descriptor
fsg_fs_intr_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	cpu_to_le16(2),
	.bInterval =		32,	// frames -> 32 ms
};

static const struct usb_descriptor_header *fsg_fs_function[] = {
	(struct usb_descriptor_header *) &fsg_otg_desc,
	(struct usb_descriptor_header *) &fsg_intf_desc,
	(struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
	(struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
	(struct usb_descriptor_header *) &fsg_fs_intr_in_desc,
	NULL,
};
#define FSG_FS_FUNCTION_PRE_EP_ENTRIES	2


/*
 * USB 2.0 devices need to expose both high speed and full speed
 * descriptors, unless they only run at full speed.
 *
 * That means alternate endpoint descriptors (bigger packets)
 * and a "device qualifier" ... plus more construction options
 * for the config descriptor.
 */
static struct usb_endpoint_descriptor
fsg_hs_bulk_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	cpu_to_le16(512),
};

static struct usb_endpoint_descriptor
fsg_hs_bulk_out_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	cpu_to_le16(512),
	.bInterval =		1,	// NAK every 1 uframe
};

static struct usb_endpoint_descriptor
fsg_hs_intr_in_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	/* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	cpu_to_le16(2),
	.bInterval =		9,	// 2**(9-1) = 256 uframes -> 32 ms
};

static const struct usb_descriptor_header *fsg_hs_function[] = {
	(struct usb_descriptor_header *) &fsg_otg_desc,
	(struct usb_descriptor_header *) &fsg_intf_desc,
	(struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
	(struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
	(struct usb_descriptor_header *) &fsg_hs_intr_in_desc,
	NULL,
};
#define FSG_HS_FUNCTION_PRE_EP_ENTRIES	2

/* Maxpacket and other transfer characteristics vary by speed. */
static struct usb_endpoint_descriptor *
fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
		struct usb_endpoint_descriptor *hs)
{
	if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
		return hs;
	return fs;
}


/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
static struct usb_string		fsg_strings[] = {
	{FSG_STRING_MANUFACTURER,	fsg_string_manufacturer},
	{FSG_STRING_PRODUCT,		fsg_string_product},
	{FSG_STRING_SERIAL,		fsg_string_serial},
	{FSG_STRING_CONFIG,		fsg_string_config},
	{FSG_STRING_INTERFACE,		fsg_string_interface},
	{}
};

static struct usb_gadget_strings	fsg_stringtab = {
	.language	= 0x0409,		// en-us
	.strings	= fsg_strings,
};


 /*-------------------------------------------------------------------------*/

/* If the next two routines are called while the gadget is registered,
 * the caller must own fsg->filesem for writing. */

static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
{
	int				ro;
	struct file			*filp = NULL;
	int				rc = -EINVAL;
	struct inode			*inode = NULL;
	loff_t				size;
	loff_t				num_sectors;
	loff_t				min_sectors;

	/* R/W if we can, R/O if we must */
	ro = curlun->ro;
	if (!ro) {
		filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
		if (-EROFS == PTR_ERR(filp))
			ro = 1;
	}
	if (ro)
		filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
	if (IS_ERR(filp)) {
		LINFO(curlun, "unable to open backing file: %s\n", filename);
		return PTR_ERR(filp);
	}

	if (!(filp->f_mode & FMODE_WRITE))
		ro = 1;

	if (filp->f_path.dentry)
		inode = filp->f_path.dentry->d_inode;
	if (inode && S_ISBLK(inode->i_mode)) {
		if (bdev_read_only(inode->i_bdev))
			ro = 1;
	} else if (!inode || !S_ISREG(inode->i_mode)) {
		LINFO(curlun, "invalid file type: %s\n", filename);
		goto out;
	}

	/* If we can't read the file, it's no good.
	 * If we can't write the file, use it read-only. */
	if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) {
		LINFO(curlun, "file not readable: %s\n", filename);
		goto out;
	}
	if (!(filp->f_op->write || filp->f_op->aio_write))
		ro = 1;

	size = i_size_read(inode->i_mapping->host);
	if (size < 0) {
		LINFO(curlun, "unable to find file size: %s\n", filename);
		rc = (int) size;
		goto out;
	}
	num_sectors = size >> 9;	// File size in 512-byte blocks
	min_sectors = 1;
	if (mod_data.cdrom) {
		num_sectors &= ~3;	// Reduce to a multiple of 2048
		min_sectors = 300*4;	// Smallest track is 300 frames
		if (num_sectors >= 256*60*75*4) {
			num_sectors = (256*60*75 - 1) * 4;
			LINFO(curlun, "file too big: %s\n", filename);
			LINFO(curlun, "using only first %d blocks\n",
					(int) num_sectors);
		}
	}
	if (num_sectors < min_sectors) {
		LINFO(curlun, "file too small: %s\n", filename);
		rc = -ETOOSMALL;
		goto out;
	}

	get_file(filp);
	curlun->ro = ro;
	curlun->filp = filp;
	curlun->file_length = size;
	curlun->num_sectors = num_sectors;
	LDBG(curlun, "open backing file: %s\n", filename);
	rc = 0;

out:
	filp_close(filp, current->files);
	return rc;
}


static void fsg_lun_close(struct fsg_lun *curlun)
{
	if (curlun->filp) {
		LDBG(curlun, "close backing file\n");
		fput(curlun->filp);
		curlun->filp = NULL;
	}
}


/*-------------------------------------------------------------------------*/

/* Sync the file data, don't bother with the metadata.
 * This code was copied from fs/buffer.c:sys_fdatasync(). */
static int fsg_lun_fsync_sub(struct fsg_lun *curlun)
{
	struct file	*filp = curlun->filp;

	if (curlun->ro || !filp)
		return 0;
	return vfs_fsync(filp, filp->f_path.dentry, 1);
}

static void store_cdrom_address(u8 *dest, int msf, u32 addr)
{
	if (msf) {
		/* Convert to Minutes-Seconds-Frames */
		addr >>= 2;		/* Convert to 2048-byte frames */
		addr += 2*75;		/* Lead-in occupies 2 seconds */
		dest[3] = addr % 75;	/* Frames */
		addr /= 75;
		dest[2] = addr % 60;	/* Seconds */
		addr /= 60;
		dest[1] = addr;		/* Minutes */
		dest[0] = 0;		/* Reserved */
	} else {
		/* Absolute sector */
		put_unaligned_be32(addr, dest);
	}
}
Commit	Line	Data
b6058d0f MN	1	/*
	2	* storage_common.c -- Common definitions for mass storage functionality
	3	*
	4	* Copyright (C) 2003-2008 Alan Stern
	5	* Copyeight (C) 2009 Samsung Electronics
	6	* Author: Michal Nazarewicz (m.nazarewicz@samsung.com)
d6181702 MN	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	21	*/
	22
	23
	24	/*
	25	* This file requires the following identifiers used in USB strings to
	26	* be defined (each of type pointer to char):
	27	* - fsg_string_manufacturer -- name of the manufacturer
	28	* - fsg_string_product -- name of the product
	29	* - fsg_string_serial -- product's serial
	30	* - fsg_string_config -- name of the configuration
	31	* - fsg_string_interface -- name of the interface
	32	* The first four are only needed when FSG_DESCRIPTORS_DEVICE_STRINGS
	33	* macro is defined prior to including this file.
b6058d0f MN	34	*/
	35
	36
d6181702 MN	37	#include <asm/unaligned.h>
d6181702 MN	38
b6058d0f MN	39
	40	/-------------------------------------------------------------------------/
	41
	42
	43	#ifndef DEBUG
	44	#undef VERBOSE_DEBUG
	45	#undef DUMP_MSGS
	46	#endif /* !DEBUG */
	47
	48	#ifdef VERBOSE_DEBUG
	49	#define VLDBG LDBG
	50	#else
	51	#define VLDBG(lun, fmt, args...) do { } while (0)
	52	#endif /* VERBOSE_DEBUG */
	53
	54	#define LDBG(lun, fmt, args...) dev_dbg (&(lun)->dev, fmt, ## args)
	55	#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
	56	#define LWARN(lun, fmt, args...) dev_warn(&(lun)->dev, fmt, ## args)
	57	#define LINFO(lun, fmt, args...) dev_info(&(lun)->dev, fmt, ## args)
	58
	59	#define DBG(d, fmt, args...) dev_dbg (&(d)->gadget->dev, fmt, ## args)
	60	#define VDBG(d, fmt, args...) dev_vdbg(&(d)->gadget->dev, fmt, ## args)
	61	#define ERROR(d, fmt, args...) dev_err (&(d)->gadget->dev, fmt, ## args)
	62	#define WARNING(d, fmt, args...) dev_warn(&(d)->gadget->dev, fmt, ## args)
	63	#define INFO(d, fmt, args...) dev_info(&(d)->gadget->dev, fmt, ## args)
	64
	65
	66
	67	#ifdef DUMP_MSGS
	68
	69	# define dump_msg(fsg, /* const char * */ label, \
	70	/* const u8 * / buf, / unsigned */ length) do { \
	71	if (length < 512) { \
	72	DBG(fsg, "%s, length %u:\n", label, length); \
	73	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, \
	74	16, 1, buf, length, 0); \
	75	} \
	76	} while (0)
	77
	78	# define dump_cdb(fsg) do { } while (0)
	79
	80	#else
	81
	82	# define dump_msg(fsg, /* const char * */ label, \
	83	/* const u8 * / buf, / unsigned */ length) do { } while (0)
	84
	85	# ifdef VERBOSE_DEBUG
	86
	87	#define dump_cdb(fsg) \
	88	print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE, \
	89	16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \
	90
	91	# else
	92
	93	# define dump_cdb(fsg) do { } while (0)
	94
	95	# endif /* VERBOSE_DEBUG */
	96
	97	#endif /* DUMP_MSGS */
	98
	99
	100
	101
	102
103	/-------------------------------------------------------------------------/
104
105	/* SCSI device types */
106	#define TYPE_DISK 0x00
107	#define TYPE_CDROM 0x05
108
109	/* USB protocol value = the transport method */
110	#define USB_PR_CBI 0x00 // Control/Bulk/Interrupt
111	#define USB_PR_CB 0x01 // Control/Bulk w/o interrupt
112	#define USB_PR_BULK 0x50 // Bulk-only
113
114	/* USB subclass value = the protocol encapsulation */
115	#define USB_SC_RBC 0x01 // Reduced Block Commands (flash)
116	#define USB_SC_8020 0x02 // SFF-8020i, MMC-2, ATAPI (CD-ROM)
117	#define USB_SC_QIC 0x03 // QIC-157 (tape)
118	#define USB_SC_UFI 0x04 // UFI (floppy)
119	#define USB_SC_8070 0x05 // SFF-8070i (removable)
120	#define USB_SC_SCSI 0x06 // Transparent SCSI
121
122	/* Bulk-only data structures */
123
124	/* Command Block Wrapper */
d6181702	125	struct fsg_bulk_cb_wrap {
b6058d0f MN	126	__le32 Signature; // Contains 'USBC'
	127	u32 Tag; // Unique per command id
	128	__le32 DataTransferLength; // Size of the data
	129	u8 Flags; // Direction in bit 7
	130	u8 Lun; // LUN (normally 0)
	131	u8 Length; // Of the CDB, <= MAX_COMMAND_SIZE
	132	u8 CDB[16]; // Command Data Block
	133	};
	134
	135	#define USB_BULK_CB_WRAP_LEN 31
	136	#define USB_BULK_CB_SIG 0x43425355 // Spells out USBC
	137	#define USB_BULK_IN_FLAG 0x80
	138
	139	/* Command Status Wrapper */
	140	struct bulk_cs_wrap {
	141	__le32 Signature; // Should = 'USBS'
	142	u32 Tag; // Same as original command
	143	__le32 Residue; // Amount not transferred
	144	u8 Status; // See below
	145	};
	146
	147	#define USB_BULK_CS_WRAP_LEN 13
	148	#define USB_BULK_CS_SIG 0x53425355 // Spells out 'USBS'
	149	#define USB_STATUS_PASS 0
	150	#define USB_STATUS_FAIL 1
	151	#define USB_STATUS_PHASE_ERROR 2
	152
	153	/* Bulk-only class specific requests */
	154	#define USB_BULK_RESET_REQUEST 0xff
	155	#define USB_BULK_GET_MAX_LUN_REQUEST 0xfe
	156
	157
	158	/* CBI Interrupt data structure */
	159	struct interrupt_data {
	160	u8 bType;
	161	u8 bValue;
	162	};
	163
	164	#define CBI_INTERRUPT_DATA_LEN 2
	165
	166	/* CBI Accept Device-Specific Command request */
	167	#define USB_CBI_ADSC_REQUEST 0x00
	168
	169
	170	#define MAX_COMMAND_SIZE 16 // Length of a SCSI Command Data Block
	171
	172	/* SCSI commands that we recognize */
	173	#define SC_FORMAT_UNIT 0x04
	174	#define SC_INQUIRY 0x12
	175	#define SC_MODE_SELECT_6 0x15
	176	#define SC_MODE_SELECT_10 0x55
	177	#define SC_MODE_SENSE_6 0x1a
	178	#define SC_MODE_SENSE_10 0x5a
	179	#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e
	180	#define SC_READ_6 0x08
	181	#define SC_READ_10 0x28
	182	#define SC_READ_12 0xa8
	183	#define SC_READ_CAPACITY 0x25
	184	#define SC_READ_FORMAT_CAPACITIES 0x23
	185	#define SC_READ_HEADER 0x44
	186	#define SC_READ_TOC 0x43
	187	#define SC_RELEASE 0x17
	188	#define SC_REQUEST_SENSE 0x03
	189	#define SC_RESERVE 0x16
190	#define SC_SEND_DIAGNOSTIC 0x1d
191	#define SC_START_STOP_UNIT 0x1b
192	#define SC_SYNCHRONIZE_CACHE 0x35
193	#define SC_TEST_UNIT_READY 0x00
194	#define SC_VERIFY 0x2f
195	#define SC_WRITE_6 0x0a
196	#define SC_WRITE_10 0x2a
197	#define SC_WRITE_12 0xaa
198
199	/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
200	#define SS_NO_SENSE 0
201	#define SS_COMMUNICATION_FAILURE 0x040800
202	#define SS_INVALID_COMMAND 0x052000
203	#define SS_INVALID_FIELD_IN_CDB 0x052400
204	#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
205	#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
206	#define SS_MEDIUM_NOT_PRESENT 0x023a00
207	#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
208	#define SS_NOT_READY_TO_READY_TRANSITION 0x062800
209	#define SS_RESET_OCCURRED 0x062900
210	#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
211	#define SS_UNRECOVERED_READ_ERROR 0x031100
212	#define SS_WRITE_ERROR 0x030c02
213	#define SS_WRITE_PROTECTED 0x072700
214
215	#define SK(x) ((u8) ((x) >> 16)) // Sense Key byte, etc.
216	#define ASC(x) ((u8) ((x) >> 8))
217	#define ASCQ(x) ((u8) (x))
218
219
220	/-------------------------------------------------------------------------/
221
222
d6181702	223	struct fsg_lun {
b6058d0f MN	224	struct file *filp;
	225	loff_t file_length;
	226	loff_t num_sectors;
	227
	228	unsigned int ro : 1;
	229	unsigned int prevent_medium_removal : 1;
	230	unsigned int registered : 1;
	231	unsigned int info_valid : 1;
	232
	233	u32 sense_data;
	234	u32 sense_data_info;
	235	u32 unit_attention_data;
	236
	237	struct device dev;
	238	};
	239
d6181702	240	#define fsg_lun_is_open(curlun) ((curlun)->filp != NULL)
b6058d0f	241
d6181702	242	static struct fsg_lun fsg_lun_from_dev(struct device dev)
b6058d0f	243	{
d6181702	244	return container_of(dev, struct fsg_lun, dev);
b6058d0f MN	245	}
	246
	247
	248	/* Big enough to hold our biggest descriptor */
	249	#define EP0_BUFSIZE 256
	250	#define DELAYED_STATUS (EP0_BUFSIZE + 999) // An impossibly large value
	251
	252	/* Number of buffers we will use. 2 is enough for double-buffering */
d6181702	253	#define FSG_NUM_BUFFERS 2
b6058d0f MN	254
	255	enum fsg_buffer_state {
	256	BUF_STATE_EMPTY = 0,
	257	BUF_STATE_FULL,
	258	BUF_STATE_BUSY
	259	};
	260
	261	struct fsg_buffhd {
	262	void *buf;
	263	enum fsg_buffer_state state;
	264	struct fsg_buffhd *next;
	265
	266	/* The NetChip 2280 is faster, and handles some protocol faults
	267	* better, if we don't submit any short bulk-out read requests.
	268	* So we will record the intended request length here. */
	269	unsigned int bulk_out_intended_length;
	270
	271	struct usb_request *inreq;
	272	int inreq_busy;
	273	struct usb_request *outreq;
	274	int outreq_busy;
	275	};
	276
	277	enum fsg_state {
	278	FSG_STATE_COMMAND_PHASE = -10, // This one isn't used anywhere
	279	FSG_STATE_DATA_PHASE,
	280	FSG_STATE_STATUS_PHASE,
	281
	282	FSG_STATE_IDLE = 0,
	283	FSG_STATE_ABORT_BULK_OUT,
	284	FSG_STATE_RESET,
	285	FSG_STATE_INTERFACE_CHANGE,
	286	FSG_STATE_CONFIG_CHANGE,
	287	FSG_STATE_DISCONNECT,
	288	FSG_STATE_EXIT,
	289	FSG_STATE_TERMINATED
	290	};
	291
	292	enum data_direction {
	293	DATA_DIR_UNKNOWN = 0,
	294	DATA_DIR_FROM_HOST,
	295	DATA_DIR_TO_HOST,
	296	DATA_DIR_NONE
	297	};
	298
	299
	300	/-------------------------------------------------------------------------/
	301
	302
	303	static inline u32 get_unaligned_be24(u8 *buf)
	304	{
	305	return 0xffffff & (u32) get_unaligned_be32(buf - 1);
	306	}
	307
	308
	309	/-------------------------------------------------------------------------/
	310
	311
d6181702 MN	312	enum {
	313	FSG_STRING_MANUFACTURER = 1,
	314	FSG_STRING_PRODUCT,
	315	FSG_STRING_SERIAL,
	316	FSG_STRING_CONFIG,
	317	FSG_STRING_INTERFACE
	318	};
b6058d0f MN	319
	320
	321	static struct usb_otg_descriptor
d6181702 MN	322	fsg_otg_desc = {
d6181702 MN	323	.bLength = sizeof fsg_otg_desc,
b6058d0f MN	324	.bDescriptorType = USB_DT_OTG,
	325
	326	.bmAttributes = USB_OTG_SRP,
	327	};
	328
	329	/* There is only one interface. */
	330
	331	static struct usb_interface_descriptor
d6181702 MN	332	fsg_intf_desc = {
d6181702 MN	333	.bLength = sizeof fsg_intf_desc,
b6058d0f MN	334	.bDescriptorType = USB_DT_INTERFACE,
	335
	336	.bNumEndpoints = 2, // Adjusted during fsg_bind()
	337	.bInterfaceClass = USB_CLASS_MASS_STORAGE,
	338	.bInterfaceSubClass = USB_SC_SCSI, // Adjusted during fsg_bind()
	339	.bInterfaceProtocol = USB_PR_BULK, // Adjusted during fsg_bind()
d6181702	340	.iInterface = FSG_STRING_INTERFACE,
b6058d0f MN	341	};
	342
	343	/* Three full-speed endpoint descriptors: bulk-in, bulk-out,
	344	* and interrupt-in. */
	345
	346	static struct usb_endpoint_descriptor
d6181702	347	fsg_fs_bulk_in_desc = {
b6058d0f MN	348	.bLength = USB_DT_ENDPOINT_SIZE,
	349	.bDescriptorType = USB_DT_ENDPOINT,
	350
	351	.bEndpointAddress = USB_DIR_IN,
	352	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	353	/* wMaxPacketSize set by autoconfiguration */
	354	};
	355
	356	static struct usb_endpoint_descriptor
d6181702	357	fsg_fs_bulk_out_desc = {
b6058d0f MN	358	.bLength = USB_DT_ENDPOINT_SIZE,
	359	.bDescriptorType = USB_DT_ENDPOINT,
	360
	361	.bEndpointAddress = USB_DIR_OUT,
	362	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	363	/* wMaxPacketSize set by autoconfiguration */
	364	};
	365
	366	static struct usb_endpoint_descriptor
d6181702	367	fsg_fs_intr_in_desc = {
b6058d0f MN	368	.bLength = USB_DT_ENDPOINT_SIZE,
	369	.bDescriptorType = USB_DT_ENDPOINT,
	370
	371	.bEndpointAddress = USB_DIR_IN,
	372	.bmAttributes = USB_ENDPOINT_XFER_INT,
	373	.wMaxPacketSize = cpu_to_le16(2),
	374	.bInterval = 32, // frames -> 32 ms
	375	};
	376
d6181702 MN	377	static const struct usb_descriptor_header *fsg_fs_function[] = {
	378	(struct usb_descriptor_header *) &fsg_otg_desc,
	379	(struct usb_descriptor_header *) &fsg_intf_desc,
	380	(struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
	381	(struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
	382	(struct usb_descriptor_header *) &fsg_fs_intr_in_desc,
b6058d0f MN	383	NULL,
b6058d0f MN	384	};
d6181702	385	#define FSG_FS_FUNCTION_PRE_EP_ENTRIES 2
b6058d0f MN	386
	387
	388	/*
	389	* USB 2.0 devices need to expose both high speed and full speed
	390	* descriptors, unless they only run at full speed.
	391	*
	392	* That means alternate endpoint descriptors (bigger packets)
	393	* and a "device qualifier" ... plus more construction options
	394	* for the config descriptor.
	395	*/
	396	static struct usb_endpoint_descriptor
d6181702	397	fsg_hs_bulk_in_desc = {
b6058d0f MN	398	.bLength = USB_DT_ENDPOINT_SIZE,
	399	.bDescriptorType = USB_DT_ENDPOINT,
	400
	401	/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
	402	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	403	.wMaxPacketSize = cpu_to_le16(512),
	404	};
	405
	406	static struct usb_endpoint_descriptor
d6181702	407	fsg_hs_bulk_out_desc = {
b6058d0f MN	408	.bLength = USB_DT_ENDPOINT_SIZE,
	409	.bDescriptorType = USB_DT_ENDPOINT,
	410
	411	/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
	412	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	413	.wMaxPacketSize = cpu_to_le16(512),
	414	.bInterval = 1, // NAK every 1 uframe
	415	};
	416
	417	static struct usb_endpoint_descriptor
d6181702	418	fsg_hs_intr_in_desc = {
b6058d0f MN	419	.bLength = USB_DT_ENDPOINT_SIZE,
	420	.bDescriptorType = USB_DT_ENDPOINT,
	421
	422	/* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
	423	.bmAttributes = USB_ENDPOINT_XFER_INT,
	424	.wMaxPacketSize = cpu_to_le16(2),
	425	.bInterval = 9, // 2**(9-1) = 256 uframes -> 32 ms
	426	};
	427
d6181702 MN	428	static const struct usb_descriptor_header *fsg_hs_function[] = {
	429	(struct usb_descriptor_header *) &fsg_otg_desc,
	430	(struct usb_descriptor_header *) &fsg_intf_desc,
	431	(struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
	432	(struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
	433	(struct usb_descriptor_header *) &fsg_hs_intr_in_desc,
b6058d0f MN	434	NULL,
b6058d0f MN	435	};
d6181702	436	#define FSG_HS_FUNCTION_PRE_EP_ENTRIES 2
b6058d0f MN	437
	438	/* Maxpacket and other transfer characteristics vary by speed. */
	439	static struct usb_endpoint_descriptor *
d6181702	440	fsg_ep_desc(struct usb_gadget g, struct usb_endpoint_descriptor fs,
b6058d0f MN	441	struct usb_endpoint_descriptor *hs)
	442	{
	443	if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
	444	return hs;
	445	return fs;
	446	}
	447
	448
b6058d0f	449	/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
d6181702 MN	450	static struct usb_string fsg_strings[] = {
	451	{FSG_STRING_MANUFACTURER, fsg_string_manufacturer},
	452	{FSG_STRING_PRODUCT, fsg_string_product},
	453	{FSG_STRING_SERIAL, fsg_string_serial},
	454	{FSG_STRING_CONFIG, fsg_string_config},
	455	{FSG_STRING_INTERFACE, fsg_string_interface},
b6058d0f MN	456	{}
	457	};
	458
d6181702	459	static struct usb_gadget_strings fsg_stringtab = {
b6058d0f	460	.language = 0x0409, // en-us
d6181702	461	.strings = fsg_strings,
b6058d0f MN	462	};
	463
	464
	465	/-------------------------------------------------------------------------/
	466
	467	/* If the next two routines are called while the gadget is registered,
	468	* the caller must own fsg->filesem for writing. */
	469
d6181702	470	static int fsg_lun_open(struct fsg_lun curlun, const char filename)
b6058d0f MN	471	{
	472	int ro;
	473	struct file *filp = NULL;
	474	int rc = -EINVAL;
	475	struct inode *inode = NULL;
	476	loff_t size;
	477	loff_t num_sectors;
	478	loff_t min_sectors;
	479
	480	/* R/W if we can, R/O if we must */
	481	ro = curlun->ro;
	482	if (!ro) {
	483	filp = filp_open(filename, O_RDWR \| O_LARGEFILE, 0);
	484	if (-EROFS == PTR_ERR(filp))
	485	ro = 1;
	486	}
	487	if (ro)
	488	filp = filp_open(filename, O_RDONLY \| O_LARGEFILE, 0);
	489	if (IS_ERR(filp)) {
	490	LINFO(curlun, "unable to open backing file: %s\n", filename);
	491	return PTR_ERR(filp);
	492	}
	493
	494	if (!(filp->f_mode & FMODE_WRITE))
	495	ro = 1;
	496
	497	if (filp->f_path.dentry)
	498	inode = filp->f_path.dentry->d_inode;
	499	if (inode && S_ISBLK(inode->i_mode)) {
	500	if (bdev_read_only(inode->i_bdev))
	501	ro = 1;
	502	} else if (!inode \|\| !S_ISREG(inode->i_mode)) {
	503	LINFO(curlun, "invalid file type: %s\n", filename);
	504	goto out;
	505	}
	506
	507	/* If we can't read the file, it's no good.
	508	* If we can't write the file, use it read-only. */
	509	if (!filp->f_op \|\| !(filp->f_op->read \|\| filp->f_op->aio_read)) {
	510	LINFO(curlun, "file not readable: %s\n", filename);
	511	goto out;
	512	}
	513	if (!(filp->f_op->write \|\| filp->f_op->aio_write))
	514	ro = 1;
	515
	516	size = i_size_read(inode->i_mapping->host);
	517	if (size < 0) {
	518	LINFO(curlun, "unable to find file size: %s\n", filename);
	519	rc = (int) size;
	520	goto out;
	521	}
	522	num_sectors = size >> 9; // File size in 512-byte blocks
	523	min_sectors = 1;
	524	if (mod_data.cdrom) {
	525	num_sectors &= ~3; // Reduce to a multiple of 2048
	526	min_sectors = 300*4; // Smallest track is 300 frames
	527	if (num_sectors >= 2566075*4) {
	528	num_sectors = (2566075 - 1) * 4;
	529	LINFO(curlun, "file too big: %s\n", filename);
	530	LINFO(curlun, "using only first %d blocks\n",
	531	(int) num_sectors);
	532	}
	533	}
	534	if (num_sectors < min_sectors) {
535	LINFO(curlun, "file too small: %s\n", filename);
536	rc = -ETOOSMALL;
537	goto out;
538	}
539
540	get_file(filp);
541	curlun->ro = ro;
542	curlun->filp = filp;
543	curlun->file_length = size;
544	curlun->num_sectors = num_sectors;
545	LDBG(curlun, "open backing file: %s\n", filename);
546	rc = 0;
547
548	out:
549	filp_close(filp, current->files);
550	return rc;
551	}
552
553
d6181702	554	static void fsg_lun_close(struct fsg_lun *curlun)
b6058d0f MN	555	{
	556	if (curlun->filp) {
	557	LDBG(curlun, "close backing file\n");
	558	fput(curlun->filp);
	559	curlun->filp = NULL;
	560	}
	561	}
	562
	563
	564	/-------------------------------------------------------------------------/
	565
	566	/* Sync the file data, don't bother with the metadata.
	567	* This code was copied from fs/buffer.c:sys_fdatasync(). */
d6181702	568	static int fsg_lun_fsync_sub(struct fsg_lun *curlun)
b6058d0f MN	569	{
	570	struct file *filp = curlun->filp;
	571
	572	if (curlun->ro \|\| !filp)
	573	return 0;
	574	return vfs_fsync(filp, filp->f_path.dentry, 1);
	575	}
	576
	577	static void store_cdrom_address(u8 *dest, int msf, u32 addr)
	578	{
	579	if (msf) {
	580	/* Convert to Minutes-Seconds-Frames */
	581	addr >>= 2; /* Convert to 2048-byte frames */
	582	addr += 275; / Lead-in occupies 2 seconds */
	583	dest[3] = addr % 75; /* Frames */
	584	addr /= 75;
	585	dest[2] = addr % 60; /* Seconds */
	586	addr /= 60;
	587	dest[1] = addr; /* Minutes */
	588	dest[0] = 0; /* Reserved */
	589	} else {
	590	/* Absolute sector */
	591	put_unaligned_be32(addr, dest);
	592	}
	593	}