*
*/
+/*
+ * In the original out of kernel Digi dgap driver, firmware
+ * loading was done via user land to driver handshaking.
+ *
+ * For cards that support a concentrator (port expander),
+ * I believe the concentrator its self told the card which
+ * concentrator is actually attached and then that info
+ * was used to tell user land which concentrator firmware
+ * image was to be downloaded. I think even the BIOS or
+ * FEP images required could change with the connection
+ * of a particular concentrator.
+ *
+ * Since I have no access to any of these cards or
+ * concentrators, I cannot put the correct concentrator
+ * firmware file names into the firmware_info structure
+ * as is now done for the BIOS and FEP images.
+ *
+ * I think, but am not certain, that the cards supporting
+ * concentrators will function without them. So support
+ * of these cards has been left in this driver.
+ *
+ * In order to fully support those cards, they would
+ * either have to be acquired for dissection or maybe
+ * Digi International could provide some assistance.
+ */
+#undef DIGI_CONCENTRATORS_SUPPORTED
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/device.h>
#include <linux/kdev_t.h>
+#include <linux/firmware.h>
#include "dgap.h"
static char *dgap_ioctl_name(int cmd);
static void dgap_do_bios_load(struct board_t *brd, uchar __user *ubios, int len);
static void dgap_do_fep_load(struct board_t *brd, uchar __user *ufep, int len);
+#ifdef DIGI_CONCENTRATORS_SUPPORTED
static void dgap_do_conc_load(struct board_t *brd, uchar *uaddr, int len);
-static void dgap_do_config_load(uchar __user *uaddr, int len);
-static int dgap_after_config_loaded(void);
+#endif
+static int dgap_after_config_loaded(int board);
static int dgap_finalize_board_init(struct board_t *brd);
+static void dgap_get_vpd(struct board_t *brd);
+static void dgap_do_reset_board(struct board_t *brd);
+static void dgap_do_wait_for_bios(struct board_t *brd);
+static void dgap_do_wait_for_fep(struct board_t *brd);
+static void dgap_sysfs_create(struct board_t *brd);
+static int dgap_firmware_load(struct pci_dev *pdev, int card_type);
/* Driver load/unload functions */
int dgap_init_module(void);
static uint dgap_poll_stop; /* Used to tell poller to stop */
static struct timer_list dgap_poll_timer;
+/*
+ SUPPORTED PRODUCTS
+
+ Card Model Number of Ports Interface
+ ----------------------------------------------------------------
+ Acceleport Xem 4 - 64 (EIA232 & EIA422)
+ Acceleport Xr 4 & 8 (EIA232)
+ Acceleport Xr 920 4 & 8 (EIA232)
+ Acceleport C/X 8 - 128 (EIA232)
+ Acceleport EPC/X 8 - 224 (EIA232)
+ Acceleport Xr/422 4 & 8 (EIA422)
+ Acceleport 2r/920 2 (EIA232)
+ Acceleport 4r/920 4 (EIA232)
+ Acceleport 8r/920 8 (EIA232)
+
+ IBM 8-Port Asynchronous PCI Adapter (EIA232)
+ IBM 128-Port Asynchronous PCI Adapter (EIA232 & EIA422)
+*/
static struct pci_device_id dgap_pci_tbl[] = {
{ DIGI_VID, PCI_DEVICE_XEM_DID, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
.remove = dgap_remove_one,
};
+struct firmware_info {
+ uchar *conf_name; /* dgap.conf */
+ uchar *bios_name; /* BIOS filename */
+ uchar *fep_name; /* FEP filename */
+ uchar *con_name; /* Concentrator filename FIXME*/
+ int num; /* sequence number */
+};
+
+/*
+ * Firmware - BIOS, FEP, and CONC filenames
+ */
+static struct firmware_info fw_info[] = {
+ { "dgap/dgap.conf", "dgap/sxbios.bin", "dgap/sxfep.bin", 0, 0 },
+ { "dgap/dgap.conf", "dgap/cxpbios.bin", "dgap/cxpfep.bin", 0, 1 },
+ { "dgap/dgap.conf", "dgap/cxpbios.bin", "dgap/cxpfep.bin", 0, 2 },
+ { "dgap/dgap.conf", "dgap/pcibios.bin", "dgap/pcifep.bin", 0, 3 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 4 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 5 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 6 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 7 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 8 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 9 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 10 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 11 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 12 },
+ { "dgap/dgap.conf", "dgap/xrbios.bin", "dgap/xrfep.bin", 0, 13 },
+ { "dgap/dgap.conf", "dgap/sxbios.bin", "dgap/sxfep.bin", 0, 14 },
+ {0,}
+};
static char *dgap_state_text[] = {
"Board Failed",
APR(("%s, Digi International Part Number %s\n", DG_NAME, DG_PART));
+ dgap_driver_state = DRIVER_NEED_CONFIG_LOAD;
+
/*
* Initialize global stuff
*/
}
else {
dgap_create_driver_sysfiles(&dgap_driver);
+ dgap_driver_state = DRIVER_READY;
}
DPR_INIT(("Finished init_module. Returning %d\n", rc));
device_create(dgap_class, NULL,
MKDEV(DIGI_DGAP_MAJOR, 0),
NULL, "dgap_mgmt");
- device_create(dgap_class, NULL,
- MKDEV(DIGI_DGAP_MAJOR, 1),
- NULL, "dgap_downld");
dgap_Major_Control_Registered = TRUE;
}
if (rc == 0) {
dgap_NumBoards++;
DPR_INIT(("Incrementing numboards to %d\n", dgap_NumBoards));
+ rc = dgap_firmware_load(pdev, ent->driver_data);
}
}
return rc;
return(0);
}
+static int dgap_firmware_load(struct pci_dev *pdev, int card_type)
+{
+ struct board_t *brd = dgap_Board[dgap_NumBoards - 1];
+ const struct firmware *fw;
+ int ret;
+
+ dgap_get_vpd(brd);
+ dgap_do_reset_board(brd);
+
+ if ((fw_info[card_type].conf_name) &&
+ (dgap_driver_state == DRIVER_NEED_CONFIG_LOAD)) {
+ ret = request_firmware(&fw, fw_info[card_type].conf_name,
+ &pdev->dev);
+ if (ret) {
+ pr_err("dgap: config file %s not found\n",
+ fw_info[card_type].conf_name);
+ return ret;
+ }
+ if (!dgap_config_buf) {
+ dgap_config_buf = kmalloc(fw->size + 1, GFP_ATOMIC);
+ if (!dgap_config_buf) {
+ release_firmware(fw);
+ return -ENOMEM;
+ }
+ }
+
+ memcpy(dgap_config_buf, fw->data, fw->size);
+ release_firmware(fw);
+ dgap_config_buf[fw->size + 1] = '\0';
+
+ if (dgap_parsefile(&dgap_config_buf, TRUE) != 0)
+ return -EINVAL;
+
+ dgap_driver_state = -1;
+ }
+
+ ret = dgap_after_config_loaded(brd->boardnum);
+ if (ret)
+ return ret;
+ /*
+ * Match this board to a config the user created for us.
+ */
+ brd->bd_config =
+ dgap_find_config(brd->type, brd->pci_bus, brd->pci_slot);
+
+ /*
+ * Because the 4 port Xr products share the same PCI ID
+ * as the 8 port Xr products, if we receive a NULL config
+ * back, and this is a PAPORT8 board, retry with a
+ * PAPORT4 attempt as well.
+ */
+ if (brd->type == PAPORT8 && !brd->bd_config)
+ brd->bd_config =
+ dgap_find_config(PAPORT4, brd->pci_bus, brd->pci_slot);
+
+ if (!brd->bd_config) {
+ pr_err("dgap: No valid configuration found\n");
+ return -EINVAL;
+ }
+
+ dgap_tty_register(brd);
+ dgap_finalize_board_init(brd);
+
+ if (fw_info[card_type].bios_name) {
+ ret = request_firmware(&fw, fw_info[card_type].bios_name,
+ &pdev->dev);
+ if (ret) {
+ pr_err("dgap: bios file %s not found\n",
+ fw_info[card_type].bios_name);
+ return ret;
+ }
+ dgap_do_bios_load(brd, (char *)fw->data, fw->size);
+ release_firmware(fw);
+
+ /* Wait for BIOS to test board... */
+ dgap_do_wait_for_bios(brd);
+
+ if (brd->state != FINISHED_BIOS_LOAD)
+ return -ENXIO;
+ }
+
+ if (fw_info[card_type].fep_name) {
+ ret = request_firmware(&fw, fw_info[card_type].fep_name,
+ &pdev->dev);
+ if (ret) {
+ pr_err("dgap: fep file %s not found\n",
+ fw_info[card_type].fep_name);
+ return ret;
+ }
+ dgap_do_fep_load(brd, (char *)fw->data, fw->size);
+ release_firmware(fw);
+
+ /* Wait for FEP to load on board... */
+ dgap_do_wait_for_fep(brd);
+
+ if (brd->state != FINISHED_FEP_LOAD)
+ return -ENXIO;
+ }
+
+#ifdef DIGI_CONCENTRATORS_SUPPORTED
+ /*
+ * If this is a CX or EPCX, we need to see if the firmware
+ * is requesting a concentrator image from us.
+ */
+ if ((bd->type == PCX) || (bd->type == PEPC)) {
+ chk_addr = (u16 *) (vaddr + DOWNREQ);
+ /* Nonzero if FEP is requesting concentrator image. */
+ check = readw(chk_addr);
+ vaddr = brd->re_map_membase;
+ }
+
+ if (fw_info[card_type].con_name && check && vaddr) {
+ ret = request_firmware(&fw, fw_info[card_type].con_name,
+ &pdev->dev);
+ if (ret) {
+ pr_err("dgap: conc file %s not found\n",
+ fw_info[card_type].con_name);
+ return ret;
+ }
+ /* Put concentrator firmware loading code here */
+ offset = readw((u16 *) (vaddr + DOWNREQ));
+ memcpy_toio(offset, fw->data, fw->size);
+
+ dgap_do_conc_load(brd, (char *)fw->data, fw->size)
+ release_firmware(fw);
+ }
+#endif
+ /*
+ * Do tty device initialization.
+ */
+ ret = dgap_tty_init(brd);
+ if (ret < 0) {
+ dgap_tty_uninit(brd);
+ pr_err("dgap: Can't init tty devices (%d)\n", ret);
+ return ret;
+ }
+
+ dgap_sysfs_create(brd);
+
+ brd->state = BOARD_READY;
+ brd->dpastatus = BD_RUNNING;
+
+ return 0;
+}
/*
* Remap PCI memory.
int i;
struct board_t *brd;
unsigned long lock_flags;
- unsigned long lock_flags2;
ulong new_time;
dgap_poll_counter++;
- /*
- * If driver needs the config file still,
- * keep trying to wake up the downloader to
- * send us the file.
- */
- if (dgap_driver_state == DRIVER_NEED_CONFIG_LOAD) {
- /*
- * Signal downloader, its got some work to do.
- */
- DGAP_LOCK(dgap_dl_lock, lock_flags2);
- if (dgap_dl_action != 1) {
- dgap_dl_action = 1;
- wake_up_interruptible(&dgap_dl_wait);
- }
- DGAP_UNLOCK(dgap_dl_lock, lock_flags2);
- goto schedule_poller;
- }
/*
* Do not start the board state machine until
* driver tells us its up and running, and has
* everything it needs.
*/
- else if (dgap_driver_state != DRIVER_READY) {
+ if (dgap_driver_state != DRIVER_READY)
goto schedule_poller;
- }
/*
* If we have just 1 board, or the system is not SMP,
return(-ENOIOCTLCMD);
}
}
-/*
- * Loads the dgap.conf config file from the user.
- */
-static void dgap_do_config_load(uchar __user *uaddr, int len)
-{
- int orig_len = len;
- char *to_addr;
- uchar __user *from_addr = uaddr;
- char buf[U2BSIZE];
- int n;
-
- to_addr = dgap_config_buf = kzalloc(len + 1, GFP_ATOMIC);
- if (!dgap_config_buf) {
- DPR_INIT(("dgap_do_config_load - unable to allocate memory for file\n"));
- dgap_driver_state = DRIVER_NEED_CONFIG_LOAD;
- return;
- }
-
- n = U2BSIZE;
- while (len) {
-
- if (n > len)
- n = len;
-
- if (copy_from_user((char *) &buf, from_addr, n) == -1 )
- return;
-
- /* Copy data from buffer to kernel memory */
- memcpy(to_addr, buf, n);
-
- /* increment counts */
- len -= n;
- to_addr += n;
- from_addr += n;
- n = U2BSIZE;
- }
-
- dgap_config_buf[orig_len] = '\0';
-
- to_addr = dgap_config_buf;
- dgap_parsefile(&to_addr, TRUE);
-
- DPR_INIT(("dgap_config_load() finish\n"));
-
- return;
-}
-
-static int dgap_after_config_loaded(void)
+static int dgap_after_config_loaded(int board)
{
- int i = 0;
- int rc = 0;
-
/*
- * Register our ttys, now that we have the config loaded.
+ * Initialize KME waitqueues...
*/
- for (i = 0; i < dgap_NumBoards; ++i) {
+ init_waitqueue_head(&(dgap_Board[board]->kme_wait));
- /*
- * Initialize KME waitqueues...
- */
- init_waitqueue_head(&(dgap_Board[i]->kme_wait));
+ /*
+ * allocate flip buffer for board.
+ */
+ dgap_Board[board]->flipbuf = kmalloc(MYFLIPLEN, GFP_ATOMIC);
+ if (!dgap_Board[board]->flipbuf)
+ return -ENOMEM;
- /*
- * allocate flip buffer for board.
- */
- dgap_Board[i]->flipbuf = kzalloc(MYFLIPLEN, GFP_ATOMIC);
- dgap_Board[i]->flipflagbuf = kzalloc(MYFLIPLEN, GFP_ATOMIC);
+ dgap_Board[board]->flipflagbuf = kmalloc(MYFLIPLEN, GFP_ATOMIC);
+ if (!dgap_Board[board]->flipflagbuf) {
+ kfree(dgap_Board[board]->flipbuf);
+ return -ENOMEM;
}
- return rc;
+ return 0;
}
-/*=======================================================================
- *
- * usertoboard - copy from user space to board space.
- *
- *=======================================================================*/
-static int dgap_usertoboard(struct board_t *brd, char *to_addr, char __user *from_addr, int len)
+/*
+ * Create pr and tty device entries
+ */
+static void dgap_sysfs_create(struct board_t *brd)
{
- char buf[U2BSIZE];
- int n = U2BSIZE;
-
- if (!brd || brd->magic != DGAP_BOARD_MAGIC)
- return -EFAULT;
-
- while (len) {
- if (n > len)
- n = len;
-
- if (copy_from_user((char *) &buf, from_addr, n) == -1 ) {
- return -EFAULT;
- }
+ struct channel_t *ch;
+ int j = 0;
- /* Copy data from buffer to card memory */
- memcpy_toio(to_addr, buf, n);
+ ch = brd->channels[0];
+ for (j = 0; j < brd->nasync; j++, ch = brd->channels[j]) {
+ struct device *classp;
+ classp = tty_register_device(brd->SerialDriver, j,
+ &(ch->ch_bd->pdev->dev));
+ ch->ch_tun.un_sysfs = classp;
+ dgap_create_tty_sysfs(&ch->ch_tun, classp);
- /* increment counts */
- len -= n;
- to_addr += n;
- from_addr += n;
- n = U2BSIZE;
+ classp = tty_register_device(brd->PrintDriver, j,
+ &(ch->ch_bd->pdev->dev));
+ ch->ch_pun.un_sysfs = classp;
+ dgap_create_tty_sysfs(&ch->ch_pun, classp);
}
- return 0;
+ dgap_create_ports_sysfiles(brd);
}
* Download bios
*/
offset = 0x1000;
- if (dgap_usertoboard(brd, addr + offset, ubios, len) == -1 ) {
- brd->state = BOARD_FAILED;
- brd->dpastatus = BD_NOFEP;
- return;
- }
+ memcpy_toio(addr + offset, ubios, len);
writel(0x0bf00401, addr);
writel(0, (addr + 4));
/* Clear the reset, and change states. */
writeb(FEPCLR, brd->re_map_port);
- brd->state = WAIT_BIOS_LOAD;
}
{
uchar *addr;
u16 word;
+ u16 err1;
+ u16 err2;
if (!brd || (brd->magic != DGAP_BOARD_MAGIC) || !brd->re_map_membase)
return;
addr = brd->re_map_membase;
word = readw(addr + POSTAREA);
- /* Check to see if BIOS thinks board is good. (GD). */
- if (word == *(u16 *) "GD") {
- DPR_INIT(("GOT GD in memory, moving states.\n"));
- brd->state = FINISHED_BIOS_LOAD;
- return;
+ /*
+ * It can take 5-6 seconds for a board to
+ * pass the bios self test and post results.
+ * Give it 10 seconds.
+ */
+ brd->wait_for_bios = 0;
+ while (brd->wait_for_bios < 1000) {
+ /* Check to see if BIOS thinks board is good. (GD). */
+ if (word == *(u16 *) "GD") {
+ DPR_INIT(("GOT GD in memory, moving states.\n"));
+ brd->state = FINISHED_BIOS_LOAD;
+ return;
+ }
+ msleep_interruptible(10);
+ brd->wait_for_bios++;
+ word = readw(addr + POSTAREA);
}
- /* Give up on board after too long of time taken */
- if (brd->wait_for_bios++ > 5000) {
- u16 err1 = readw(addr + SEQUENCE);
- u16 err2 = readw(addr + ERROR);
- APR(("***WARNING*** %s failed diagnostics. Error #(%x,%x).\n",
- brd->name, err1, err2));
- brd->state = BOARD_FAILED;
- brd->dpastatus = BD_NOFEP;
- }
+ /* Gave up on board after too long of time taken */
+ err1 = readw(addr + SEQUENCE);
+ err2 = readw(addr + ERROR);
+ APR(("***WARNING*** %s failed diagnostics. Error #(%x,%x).\n",
+ brd->name, err1, err2));
+ brd->state = BOARD_FAILED;
+ brd->dpastatus = BD_NOBIOS;
}
* Copies the FEP code from the user to the board,
* and starts the FEP running.
*/
-static void dgap_do_fep_load(struct board_t *brd, uchar __user *ufep, int len)
+static void dgap_do_fep_load(struct board_t *brd, uchar *ufep, int len)
{
uchar *addr;
uint offset;
* Download FEP
*/
offset = 0x1000;
- if (dgap_usertoboard(brd, addr + offset, ufep, len) == -1 ) {
- brd->state = BOARD_FAILED;
- brd->dpastatus = BD_NOFEP;
- return;
- }
+ memcpy_toio(addr + offset, ufep, len);
/*
* If board is a concentrator product, we need to give
writel(0xbfc01004, (addr + 0xc34));
writel(0x3, (addr + 0xc30));
- /* change states. */
- brd->state = WAIT_FEP_LOAD;
-
DPR_INIT(("dgap_do_fep_load() for board %s : finish\n", brd->name));
}
{
uchar *addr;
u16 word;
+ u16 err1;
+ u16 err2;
if (!brd || (brd->magic != DGAP_BOARD_MAGIC) || !brd->re_map_membase)
return;
addr = brd->re_map_membase;
-
- DPR_INIT(("dgap_do_wait_for_fep() for board %s : start. addr: %p\n", brd->name, addr));
-
word = readw(addr + FEPSTAT);
- /* Check to see if FEP is up and running now. */
- if (word == *(u16 *) "OS") {
- DPR_INIT(("GOT OS in memory for board %s, moving states.\n", brd->name));
- brd->state = FINISHED_FEP_LOAD;
+ /*
+ * It can take 2-3 seconds for the FEP to
+ * be up and running. Give it 5 secs.
+ */
+ brd->wait_for_fep = 0;
+ while (brd->wait_for_fep < 500) {
+ /* Check to see if FEP is up and running now. */
+ if (word == *(u16 *) "OS") {
+ brd->state = FINISHED_FEP_LOAD;
+ /*
+ * Check to see if the board can support FEP5+ commands.
+ */
+ word = readw(addr + FEP5_PLUS);
+ if (word == *(u16 *) "5A")
+ brd->bd_flags |= BD_FEP5PLUS;
- /*
- * Check to see if the board can support FEP5+ commands.
- */
- word = readw(addr + FEP5_PLUS);
- if (word == *(u16 *) "5A") {
- DPR_INIT(("GOT 5A in memory for board %s, board supports extended FEP5 commands.\n", brd->name));
- brd->bd_flags |= BD_FEP5PLUS;
+ return;
}
-
- return;
+ msleep_interruptible(10);
+ brd->wait_for_fep++;
+ word = readw(addr + FEPSTAT);
}
- /* Give up on board after too long of time taken */
- if (brd->wait_for_fep++ > 5000) {
- u16 err1 = readw(addr + SEQUENCE);
- u16 err2 = readw(addr + ERROR);
- APR(("***WARNING*** FEPOS for %s not functioning. Error #(%x,%x).\n",
- brd->name, err1, err2));
- brd->state = BOARD_FAILED;
- brd->dpastatus = BD_NOFEP;
- }
+ /* Gave up on board after too long of time taken */
+ err1 = readw(addr + SEQUENCE);
+ err2 = readw(addr + ERROR);
+ APR(("***WARNING*** FEPOS for %s not functioning. Error #(%x,%x).\n",
+ brd->name, err1, err2));
+ brd->state = BOARD_FAILED;
+ brd->dpastatus = BD_NOFEP;
DPR_INIT(("dgap_do_wait_for_fep() for board %s : finish\n", brd->name));
}
}
+#ifdef DIGI_CONCENTRATORS_SUPPORTED
/*
* Sends a concentrator image into the FEP5 board.
*/
offset = readw((u16 *) (vaddr + DOWNREQ));
to_dp = (struct downld_t *) (vaddr + (int) offset);
-
- /*
- * The image was already read into kernel space,
- * we do NOT need a user space read here
- */
- memcpy_toio((char *) to_dp, uaddr, sizeof(struct downld_t));
+ memcpy_toio(to_dp, uaddr, len);
/* Tell card we have data for it */
writew(0, vaddr + (DOWNREQ));
brd->conc_dl_status = NO_PENDING_CONCENTRATOR_REQUESTS;
}
-
+#endif
#define EXPANSION_ROM_SIZE (64 * 1024)
#define FEP5_ROM_MAGIC (0xFEFFFFFF)
ulong lock_flags2;
char *vaddr;
u16 head, tail;
- u16 *chk_addr;
- u16 check = 0;
if (!bd || (bd->magic != DGAP_BOARD_MAGIC)) {
APR(("dgap_poll_tasklet() - NULL or bad bd.\n"));
goto out;
}
- /*
- * If this is a CX or EPCX, we need to see if the firmware
- * is requesting a concentrator image from us.
- */
- if ((bd->type == PCX) || (bd->type == PEPC)) {
- chk_addr = (u16 *) (vaddr + DOWNREQ);
- check = readw(chk_addr);
- /* Nonzero if FEP is requesting concentrator image. */
- if (check) {
- if (bd->conc_dl_status == NO_PENDING_CONCENTRATOR_REQUESTS)
- bd->conc_dl_status = NEED_CONCENTRATOR;
- /*
- * Signal downloader, its got some work to do.
- */
- DGAP_LOCK(dgap_dl_lock, lock_flags2);
- if (dgap_dl_action != 1) {
- dgap_dl_action = 1;
- wake_up_interruptible(&dgap_dl_wait);
- }
- DGAP_UNLOCK(dgap_dl_lock, lock_flags2);
-
- }
- }
-
eaddr = (struct ev_t *) (vaddr + EVBUF);
/* Get our head and tail */
projects / openwrt / staging / blogic.git / commitdiff