[U-Boot] =?y?q?=5BPATCH=201/4=5D=20usb=3Acomposite=3A=20USB=20Mass=20Storage=20-=20storage=5Fcommon=2Ec=20from=20Linux=20kernel?=

Piotr Wilczek
2013-01-23T08:42:26Z

From: Lukasz Majewski <l.majewski@samsung.com>

The storage_common.c source file from v2.6.36 Linux kernel.

commit d26a6aa08b9f12b44fb1ee65625e7480d3d5bb81
Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
Date: Mon Nov 9 14:15:23 2009 +0100

USB: g_mass_storage: code cleaned up and comments updated

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
drivers/usb/gadget/storage_common.c | 654 +++++++++++++++++++++++++++++++++++
1 file changed, 654 insertions(+)
create mode 100644 drivers/usb/gadget/storage_common.c

diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c
new file mode 100644
index 0000000..1dbc4b5
--- /dev/null
+++ b/drivers/usb/gadget/storage_common.c
@@ -0,0 +1,654 @@
+/*
+ * 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 at samsung.com)
+ *
+ * Ported to u-boot:
+ * Andrzej Pietrasiewicz <andrzej.p@samsung.com>
+ *
+ * Code refactoring & cleanup:
+ * ??ukasz Majewski <l.majewski@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.
+ */
+
+/*
+ * When FSG_NO_INTR_EP is defined fsg_fs_intr_in_desc and
+ * fsg_hs_intr_in_desc objects as well as
+ * FSG_FS_FUNCTION_PRE_EP_ENTRIES and FSG_HS_FUNCTION_PRE_EP_ENTRIES
+ * macros are not defined.
+ *
+ * When FSG_NO_DEVICE_STRINGS is defined FSG_STRING_MANUFACTURER,
+ * FSG_STRING_PRODUCT, FSG_STRING_SERIAL and FSG_STRING_CONFIG are not
+ * defined (as well as corresponding entries in string tables are
+ * missing) and FSG_STRING_INTERFACE has value of zero.
+ *
+ * When FSG_NO_OTG is defined fsg_otg_desc won't be defined.
+ */
+
+/*
+ * When FSG_BUFFHD_STATIC_BUFFER is defined when this file is included
+ * the fsg_buffhd structure's buf field will be an array of FSG_BUFLEN
+ * characters rather then a pointer to void.
+ */
+
+
+/* #include <asm/unaligned.h> */
+
+
+/*
+ * Thanks to NetChip Technologies for donating this product ID.
+ *
+ * DO NOT REUSE THESE IDs with any other driver!! Ever!!
+ * Instead: allocate your own, using normal USB-IF procedures.
+ */
+#define FSG_VENDOR_ID 0x0525 /* NetChip */
+#define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
+
+/*-------------------------------------------------------------------------*/
+
+#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 LDBG(lun, fmt, args...) do { } while (0)
+#define LERROR(lun, fmt, args...) do { } while (0)
+#define LWARN(lun, fmt, args...) do { } while (0)
+#define LINFO(lun, fmt, args...) do { } while (0)
+
+/*
+ * Keep those macros in sync with those in
+ * include/linux/usb/composite.h or else GCC will complain. If they
+ * are identical (the same names of arguments, white spaces in the
+ * same places) GCC will allow redefinition otherwise (even if some
+ * white space is removed or added) warning will be issued.
+ *
+ * Those macros are needed here because File Storage Gadget does not
+ * include the composite.h header. For composite gadgets those macros
+ * are redundant since composite.h is included any way.
+ *
+ * One could check whether those macros are already defined (which
+ * would indicate composite.h had been included) or not (which would
+ * indicate we were in FSG) but this is not done because a warning is
+ * desired if definitions here differ from the ones in composite.h.
+ *
+ * We want the definitions to match and be the same in File Storage
+ * Gadget as well as Mass Storage Function (and so composite gadgets
+ * using MSF). If someone changes them in composite.h it will produce
+ * a warning in this file when building MSF.
+ */
+
+#define DBG(d, fmt, args...) debug(fmt , ## args)
+#define VDBG(d, fmt, args...) debug(fmt , ## args)
+/* #define ERROR(d, fmt, args...) printf(fmt , ## args) */
+/* #define WARNING(d, fmt, args...) printf(fmt , ## args) */
+/* #define INFO(d, fmt, args...) printf(fmt , ## args) */
+
+/* #define DBG(d, fmt, args...) do { } while (0) */
+/* #define VDBG(d, fmt, args...) do { } while (0) */
+#define ERROR(d, fmt, args...) do { } while (0)
+#define WARNING(d, fmt, args...) do { } while (0)
+#define INFO(d, fmt, args...) do { } while (0)
+
+#ifdef DUMP_MSGS
+
+/* dump_msg(fsg, const char * label, const u8 * buf, unsigned length); */
+# define dump_msg(fsg, label, buf, 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
+
+/* Length of a SCSI Command Data Block */
+#define MAX_COMMAND_SIZE 16
+
+/* 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 device_attribute { int i; };
+struct rw_semaphore { int i; };
+#define down_write(...) do { } while (0)
+#define up_write(...) do { } while (0)
+#define down_read(...) do { } while (0)
+#define up_read(...) do { } while (0)
+#define ETOOSMALL 525
+
+#include <usb_mass_storage.h>
+extern struct ums_board_info *ums_info;
+
+/*-------------------------------------------------------------------------*/
+
+struct fsg_lun {
+ loff_t file_length;
+ loff_t num_sectors;
+
+ unsigned int initially_ro:1;
+ unsigned int ro:1;
+ unsigned int removable:1;
+ unsigned int cdrom:1;
+ unsigned int prevent_medium_removal:1;
+ unsigned int registered:1;
+ unsigned int info_valid:1;
+ unsigned int nofua:1;
+
+ u32 sense_data;
+ u32 sense_data_info;
+ u32 unit_attention_data;
+
+ struct device dev;
+};
+
+#define fsg_lun_is_open(curlun) ((curlun)->filp != NULL)
+#if 0
+static struct fsg_lun *fsg_lun_from_dev(struct device *dev)
+{
+ return container_of(dev, struct fsg_lun, dev);
+}
+#endif
+
+/* 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
+
+/* Default size of buffer length. */
+#define FSG_BUFLEN ((u32)16384)
+
+/* Maximal number of LUNs supported in mass storage function */
+#define FSG_MAX_LUNS 8
+
+enum fsg_buffer_state {
+ BUF_STATE_EMPTY = 0,
+ BUF_STATE_FULL,
+ BUF_STATE_BUSY
+};
+
+struct fsg_buffhd {
+#ifdef FSG_BUFFHD_STATIC_BUFFER
+ char buf[FSG_BUFLEN];
+#else
+ void *buf;
+#endif
+ 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 {
+ /* This one isn't used anywhere */
+ FSG_STATE_COMMAND_PHASE = -10,
+ 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 {
+#ifndef FSG_NO_DEVICE_STRINGS
+ FSG_STRING_MANUFACTURER = 1,
+ FSG_STRING_PRODUCT,
+ FSG_STRING_SERIAL,
+ FSG_STRING_CONFIG,
+#endif
+ FSG_STRING_INTERFACE
+};
+
+#ifndef FSG_NO_OTG
+static struct usb_otg_descriptor
+fsg_otg_desc = {
+ .bLength = sizeof fsg_otg_desc,
+ .bDescriptorType = USB_DT_OTG,
+
+ .bmAttributes = USB_OTG_SRP,
+};
+#endif
+
+/* 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 */
+};
+
+#ifndef FSG_NO_INTR_EP
+
+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 */
+};
+
+#ifndef FSG_NO_OTG
+# define FSG_FS_FUNCTION_PRE_EP_ENTRIES 2
+#else
+# define FSG_FS_FUNCTION_PRE_EP_ENTRIES 1
+#endif
+
+#endif
+
+static struct usb_descriptor_header *fsg_fs_function[] = {
+#ifndef FSG_NO_OTG
+ (struct usb_descriptor_header *) &fsg_otg_desc,
+#endif
+ (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,
+#ifndef FSG_NO_INTR_EP
+ (struct usb_descriptor_header *) &fsg_fs_intr_in_desc,
+#endif
+ NULL,
+};
+
+/*
+ * 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 configuration 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 */
+};
+
+#ifndef FSG_NO_INTR_EP
+
+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 */
+};
+
+#ifndef FSG_NO_OTG
+# define FSG_HS_FUNCTION_PRE_EP_ENTRIES 2
+#else
+# define FSG_HS_FUNCTION_PRE_EP_ENTRIES 1
+#endif
+
+#endif
+
+static struct usb_descriptor_header *fsg_hs_function[] = {
+#ifndef FSG_NO_OTG
+ (struct usb_descriptor_header *) &fsg_otg_desc,
+#endif
+ (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,
+#ifndef FSG_NO_INTR_EP
+ (struct usb_descriptor_header *) &fsg_hs_intr_in_desc,
+#endif
+ NULL,
+};
+
+/* 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[] = {
+#ifndef FSG_NO_DEVICE_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},
+#endif
+ {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;
+ int rc = -EINVAL;
+ loff_t size;
+ loff_t num_sectors;
+ loff_t min_sectors;
+
+ /* R/W if we can, R/O if we must */
+ ro = curlun->initially_ro;
+
+ ums_info->get_capacity(&(ums_info->ums_dev), &size);
+ if (size < 0) {
+ printf("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 (num_sectors < min_sectors) {
+ printf("file too small: %s\n", filename);
+ rc = -ETOOSMALL;
+ goto out;
+ }
+
+ curlun->ro = ro;
+ curlun->file_length = size;
+ curlun->num_sectors = num_sectors;
+ debug("open backing file: %s\n", filename);
+ rc = 0;
+
+out:
+ return rc;
+}
+
+#if 0
+static void fsg_lun_close(struct fsg_lun *curlun)
+{
+}
+#endif
+/*-------------------------------------------------------------------------*/
+
+/*
+ * 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)
+{
+ return 0;
+}
+
+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);
+ }
+}
+
+/*-------------------------------------------------------------------------*/
--
1.7.9.5