/*
* 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.
*
* Original driver code supplied by Multi-Tech
*
* Changes
* 1/9/98 alan@redhat.com Merge to 2.0.x kernel tree
* Obtain and use official major/minors
* Loader switched to a misc device
* (fixed range check bug as a side effect)
* Printk clean up
* 9/12/98 alan@redhat.com Rough port to 2.1.x
*
* 10/6/99 sameer Merged the ISA and PCI drivers to
* a new unified driver.
*
* 3/9/99 sameer Added support for ISI4616 cards.
*
* 16/9/99 sameer We do not force RTS low anymore.
* This is to prevent the firmware
* from getting confused.
*
* 26/10/99 sameer Cosmetic changes:The driver now
* dumps the Port Count information
* along with I/O address and IRQ.
*
* 13/12/99 sameer Fixed the problem with IRQ sharing.
*
* 10/5/00 sameer Fixed isicom_shutdown_board()
* to not lower DTR on all the ports
* when the last port on the card is
* closed.
*
* 10/5/00 sameer Signal mask setup command added
* to isicom_setup_port and
* isicom_shutdown_port.
*
* 24/5/00 sameer The driver is now SMP aware.
*
*
* 27/11/00 Vinayak P Risbud Fixed the Driver Crash Problem
*
*
* 03/01/01 anil .s Added support for resetting the
* internal modems on ISI cards.
*
* 08/02/01 anil .s Upgraded the driver for kernel
* 2.4.x
*
* 11/04/01 Kevin Fixed firmware load problem with
* ISIHP-4X card
*
* 30/04/01 anil .s Fixed the remote login through
* ISI port problem. Now the link
* does not go down before password
* prompt.
*
* 03/05/01 anil .s Fixed the problem with IRQ sharing
* among ISI-PCI cards.
*
* 03/05/01 anil .s Added support to display the version
* info during insmod as well as module
* listing by lsmod.
*
* 10/05/01 anil .s Done the modifications to the source
* file and Install script so that the
* same installation can be used for
* 2.2.x and 2.4.x kernel.
*
* 06/06/01 anil .s Now we drop both dtr and rts during
* shutdown_port as well as raise them
* during isicom_config_port.
*
* 09/06/01 acme@conectiva.com.br use capable, not suser, do
* restore_flags on failure in
* isicom_send_break, verify put_user
* result
*
* 11/02/03 ranjeeth Added support for 230 Kbps and 460 Kbps
* Baud index extended to 21
*
* 20/03/03 ranjeeth Made to work for Linux Advanced server.
* Taken care of license warning.
*
* 10/12/03 Ravindra Made to work for Fedora Core 1 of
* Red Hat Distribution
*
* 06/01/05 Alan Cox Merged the ISI and base kernel strands
* into a single 2.6 driver
*
* ***********************************************************
*
* To use this driver you also need the support package. You
* can find this in RPM format on
* ftp://ftp.linux.org.uk/pub/linux/alan
*
* You can find the original tools for this direct from Multitech
* ftp://ftp.multitech.com/ISI-Cards/
*
* Having installed the cards the module options (/etc/modprobe.conf)
*
* options isicom io=card1,card2,card3,card4 irq=card1,card2,card3,card4
*
* Omit those entries for boards you don't have installed.
*
* TODO
* Merge testing
* 64-bit verification
*/
#include <linux/module.h>
#include <linux/firmware.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/termios.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/serial.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <asm/system.h>
#include <linux/pci.h>
#include <linux/isicom.h>
#define InterruptTheCard(base) outw(0, (base) + 0xc)
#define ClearInterrupt(base) inw((base) + 0x0a)
#define pr_dbg(str...) pr_debug("ISICOM: " str)
#ifdef DEBUG
#define isicom_paranoia_check(a, b, c) __isicom_paranoia_check((a), (b), (c))
#else
#define isicom_paranoia_check(a, b, c) 0
#endif
static int isicom_probe(struct pci_dev *, const struct pci_device_id *);
static void __devexit isicom_remove(struct pci_dev *);
static struct pci_device_id isicom_pci_tbl[] = {
{ PCI_DEVICE(VENDOR_ID, 0x2028) },
{ PCI_DEVICE(VENDOR_ID, 0x2051) },
{ PCI_DEVICE(VENDOR_ID, 0x2052) },
{ PCI_DEVICE(VENDOR_ID, 0x2053) },
{ PCI_DEVICE(VENDOR_ID, 0x2054) },
{ PCI_DEVICE(VENDOR_ID, 0x2055) },
{ PCI_DEVICE(VENDOR_ID, 0x2056) },
{ PCI_DEVICE(VENDOR_ID, 0x2057) },
{ PCI_DEVICE(VENDOR_ID, 0x2058) },
{ 0 }
};
MODULE_DEVICE_TABLE(pci, isicom_pci_tbl);
static struct pci_driver isicom_driver = {
.name = "isicom",
.id_table = isicom_pci_tbl,
.probe = isicom_probe,
.remove = __devexit_p(isicom_remove)
};
static int prev_card = 3; /* start servicing isi_card[0] */
static struct tty_driver *isicom_normal;
static void isicom_tx(unsigned long _data);
static void isicom_start(struct tty_struct *tty);
static DEFINE_TIMER(tx, isicom_tx, 0, 0);
/* baud index mappings from linux defns to isi */
static signed char linuxb_to_isib[] = {
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 18, 19, 20, 21
};
struct isi_board {
unsigned long base;
int irq;
unsigned char port_count;
unsigned short status;
unsigned short port_status; /* each bit for each port */
unsigned short shift_count;
struct isi_port *ports;
signed char count;
spinlock_t card_lock; /* Card wide lock 11/5/00 -sameer */
unsigned long flags;
unsigned int index;
};
struct isi_port {
unsigned short magic;
struct tty_port port;
u16 channel;
u16 status;
struct isi_board *card;
unsigned char *xmit_buf;
int xmit_head;
int xmit_tail;
int xmit_cnt;
};
static struct isi_board isi_card[BOARD_COUNT];
static struct isi_port isi_ports[PORT_COUNT];
/*
* Locking functions for card level locking. We need to own both
* the kernel lock for the card and have the card in a position that
* it wants to talk.
*/
static inline int WaitTillCardIsFree(unsigned long base)
{
unsigned int count = 0;
unsigned int a = in_atomic(); /* do we run under spinlock? */
while (!(inw(base + 0xe) & 0x1) && count++ < 100)
if (a)
mdelay(1);
else
msleep(1);
return !(inw(base + 0xe) & 0x1);
}
static int lock_card(struct isi_board *card)
{
unsigned long base = card->base;
unsigned int retries, a;
for (retries = 0; retries < 10; retries++) {
spin_lock_irqsave(&card->card_lock, card->flags);
for (a = 0; a < 10; a++) {
if (inw(base + 0xe) & 0x1)
return 1;
udelay(10);
}
spin_unlock_irqrestore(&card->card_lock, card->flags);
msleep(10);
}
printk(KERN_WARNING "ISICOM: Failed to lock Card (0x%lx)\n",
card->base);
return 0; /* Failed to acquire the card! */
}
static void unlock_card(struct isi_board *card)
{
spin_unlock_irqrestore(&card->card_lock, card->flags);
}
/*
* ISI Card specific ops ...
*/
/* card->lock HAS to be held */
static void raise_dtr(struct isi_port *port)
{
struct isi_board *card = port->card;
unsigned long base = card->base;
u16 channel = port->channel;
if (WaitTillCardIsFree(base))
return;
outw(0x8000 | (channel << card->shift_count) | 0x02, base);
outw(0x0504, base);
InterruptTheCard(base);
port->status |= ISI_DTR;
}
/* card->lock HAS to be held */
static inline void drop_dtr(struct isi_port *port)
{
struct isi_board *card = port->card;
unsigned long base = card->base;
u16 channel = port->channel;
if (WaitTillCardIsFree(base))
return;
outw(0x8000 | (channel << card->shift_count) | 0x02, base);
outw(0x0404, base);
InterruptTheCard(base);
port->status &= ~ISI_DTR;
}
/* card->lock HAS to be held */
static inline void raise_rts(struct isi_port *port)
{
struct isi_board *card = port->card;
unsigned long base = card->base;
u16 channel = port->channel;
if (WaitTillCardIsFree(base))
return;
outw(0x8000 | (channel << card->shift_count) | 0x02, base);
outw(0x0a04, base);
InterruptTheCard(base);
port->status |= ISI_RTS;
}
/* card->lock HAS to be held */
static inline void drop_rts(struct isi_port *port)
{
struct isi_board *card = port->card;
unsigned long base = card->base;
u16 channel = port->channel;
if (WaitTillCardIsFree(base))
return;
outw(0x8000 | (channel << card->shift_count) | 0x02, base);
outw(0x0804, base);
InterruptTheCard(base);
port->status &= ~ISI_RTS;
}
/* card->lock MUST NOT be held */
static inline void raise_dtr_rts(struct isi_port *port)
{
struct isi_board *card = port->card;
unsigned long base = card->base;
u16 channel = port->channel;
if (!lock_card(card))
return;
outw(0x8000 | (channel << card->shift_count) | 0x02, base);
outw(0x0f04, base);
InterruptTheCard(base);
port->status |= (ISI_DTR | ISI_RTS);
unlock_card(card);
}
/* card->lock HAS to be held */
static void drop_dtr_rts(struct isi_port *port)
{
struct isi_board *card = port->card;
unsigned long base = card->base;
u16 channel = port->channel;
if (WaitTillCardIsFree(base))
return;
outw(0x8000 | (channel << card->shift_count) | 0x02, base);
outw(0x0c04, base);
InterruptTheCard(base);
port->status &= ~(ISI_RTS | ISI_DTR);
}
/*
* ISICOM Driver specific routines ...
*
*/
static inline int __isicom_paranoia_check(struct isi_port const *port,
char *name, const char *routine)
{
if (!port) {
printk(KERN_WARNING "ISICOM: Warning: bad isicom magic for "
"dev %s in %s.\n", name, routine);
return 1;
}
if (port->magic != ISICOM_MAGIC) {
printk(KERN_WARNING "ISICOM: Warning: NULL isicom port for "
"dev %s in %s.\n", name, routine);
return 1;
}
return 0;
}
/*
* Transmitter.
*
* We shovel data into the card buffers on a regular basis. The card
* will do the rest of the work for us.
*/
static void isicom_tx(unsigned long _data)
{
unsigned long flags, base;
unsigned int retries;
short count = (BOARD_COUNT-1), card;
short txcount, wrd, residue, word_count, cnt;
struct isi_port *port;
struct tty_struct *tty;
/* find next active board */
card = (prev_card + 1) & 0x0003;
while (count-- > 0) {
if (isi_card[card].status & BOARD_ACTIVE)
break;
card = (card + 1) & 0x0003;
}
if (!(isi_card[card].status & BOARD_ACTIVE))
goto sched_again;
prev_card = card;
count = isi_card[card].port_count;
port = isi_card[card].ports;
base = isi_card[card].base;
spin_lock_irqsave(&isi_card[card].card_lock, flags);
for (retries = 0; retries < 100; retries++) {
if (inw(base + 0xe) & 0x1)
break;
udelay(2);
}
if (retries >= 100)
goto unlock;
for (; count > 0; count--, port++) {
/* port not active or tx disabled to force flow control */
if (!(port->port.flags & ASYNC_INITIALIZED) ||
!(port->status & ISI_TXOK))
continue;
tty = port->port.tty;
if (tty == NULL)
continue;
txcount = min_t(short, TX_SIZE, port->xmit_cnt);
if (txcount <= 0 || tty->stopped || tty->hw_stopped)
continue;
if (!(inw(base + 0x02) & (1 << port->channel)))
continue;
pr_dbg("txing %d bytes, port%d.\n", txcount,
port->channel + 1);
outw((port->channel << isi_card[card].shift_count) | txcount,
base);
residue = NO;
wrd = 0;
while (1) {
cnt = min_t(int, txcount, (SERIAL_XMIT_SIZE
- port->xmit_tail));
if (residue == YES) {
residue = NO;
if (cnt > 0) {
wrd |= (port->port.xmit_buf[port->xmit_tail]
<< 8);
port->xmit_tail = (port->xmit_tail + 1)
& (SERIAL_XMIT_SIZE - 1);
port->xmit_cnt--;
txcount--;
cnt--;
outw(wrd, base);
} else {
outw(wrd, base);
break;
}
}
if (cnt <= 0)
break;
word_count = cnt >> 1;
outsw(base, port->port.xmit_buf+port->xmit_tail, word_count);
port->xmit_tail = (port->xmit_tail
+ (word_count << 1)) & (SERIAL_XMIT_SIZE - 1);
txcount -= (word_count << 1);
port->xmit_cnt -= (word_count << 1);
if (cnt & 0x0001) {
residue = YES;
wrd = port->port.xmit_buf[port->xmit_tail];
port->xmit_tail = (port->xmit_tail + 1)
& (SERIAL_XMIT_SIZE - 1);
port->xmit_cnt--;
txcount--;
}
}
InterruptTheCard(base);
if (port->xmit_cnt <= 0)
port->status &= ~ISI_TXOK;
if (port->xmit_cnt <= WAKEUP_CHARS)
tty_wakeup(tty);
}
unlock:
spin_unlock_irqrestore(&isi_card[card].card_lock, flags);
/* schedule another tx for hopefully in about 10ms */
sched_again:
mod_timer(&tx, jiffies + msecs_to_jiffies(10));
}
/*
* Main interrupt handler routine
*/
static irqreturn_t isicom_interrupt(int irq, void *dev_id)
{
struct isi_board *card = dev_id;
struct isi_port *port;
struct tty_struct *tty;
unsigned long base;
u16 header, word_count, count, channel;
short byte_count;
unsigned char *rp;
if (!card || !(card->status & FIRMWARE_LOADED))
return IRQ_NONE;
base = card->base;
/* did the card interrupt us? */
if (!(inw(base + 0x0e) & 0x02))
return IRQ_NONE;
spin_lock(&card->card_lock);
/*
* disable any interrupts from the PCI card and lower the
* interrupt line
*/
outw(0x8000, base+0x04);
ClearInterrupt(base);
inw(base); /* get the dummy word out */
header = inw(base);
channel = (header & 0x7800) >> card->shift_count;
byte_count = header & 0xff;
if (channel + 1 > card->port_count) {
printk(KERN_WARNING "ISICOM: isicom_interrupt(0x%lx): "
"%d(channel) > port_count.\n", base, channel+1);
outw(0x0000, base+0x04); /* enable interrupts */
spin_unlock(&card->card_lock);
return IRQ_HANDLED;
}
port = card->ports + channel;
if (!(port->port.flags & ASYNC_INITIALIZED)) {
outw(0x0000, base+0x04); /* enable interrupts */
spin_unlock(&card->card_lock);
return IRQ_HANDLED;
}
tty = port->port.tty;
if (tty == NULL) {
word_count = byte_count >> 1;
while (byte_count > 1) {
inw(base);
byte_count -= 2;
}
if (byte_count & 0x01)
inw(base);
outw(0x0000, base+0x04); /* enable interrupts */
spin_unlock(&card->card_lock);
return IRQ_HANDLED;
}
if (header & 0x8000) { /* Status Packet */
header = inw(base);
switch (header & 0xff) {
case 0: /* Change in EIA signals */
if (port->port.flags & ASYNC_CHECK_CD) {
if (port->status & ISI_DCD) {
if (!(header & ISI_DCD)) {
/* Carrier has been lost */
pr_dbg("interrupt: DCD->low.\n"
);
port->status &= ~ISI_DCD;
tty_hangup(tty);
}
} else if (header & ISI_DCD) {
/* Carrier has been detected */
pr_dbg("interrupt: DCD->high.\n");
port->status |= ISI_DCD;
wake_up_interruptible(&port->port.open_wait);
}
} else {
if (header & ISI_DCD)
port->status |= ISI_DCD;
else
port->status &= ~ISI_DCD;
}
if (port->port.flags & ASYNC_CTS_FLOW) {
if (port->port.tty->hw_stopped) {
if (header & ISI_CTS) {
port->port.tty->hw_stopped = 0;
/* start tx ing */
port->status |= (ISI_TXOK
| ISI_CTS);
tty_wakeup(tty);
}
} else if (!(header & ISI_CTS)) {
port->port.tty->hw_stopped = 1;
/* stop tx ing */
port->status &= ~(ISI_TXOK | ISI_CTS);
}
} else {
if (header & ISI_CTS)
port->status |= ISI_CTS;
else
port->status &= ~ISI_CTS;
}
if (header & ISI_DSR)
port->status |= ISI_DSR;
else
port->status &= ~ISI_DSR;
if (header & ISI_RI)
port->status |= ISI_RI;
else
port->status &= ~ISI_RI;
break;
case 1: /* Received Break !!! */
tty_insert_flip_char(tty, 0, TTY_BREAK);
if (port->port.flags & ASYNC_SAK)
do_SAK(tty);
tty_flip_buffer_push(tty);
break;
case 2: /* Statistics */
pr_dbg("isicom_interrupt: stats!!!.\n");
break;
default:
pr_dbg("Intr: Unknown code in status packet.\n");
break;
}
} else { /* Data Packet */
count = tty_prepare_flip_string(tty, &rp, byte_count & ~1);
pr_dbg("Intr: Can rx %d of %d bytes.\n", count, byte_count);
word_count = count >> 1;
insw(base, rp, word_count);
byte_count -= (word_count << 1);
if (count & 0x0001) {
tty_insert_flip_char(tty, inw(base) & 0xff,
TTY_NORMAL);
byte_count -= 2;
}
if (byte_count > 0) {
pr_dbg("Intr(0x%lx:%d): Flip buffer overflow! dropping "
"bytes...\n", base, channel + 1);
/* drain out unread xtra data */
while (byte_count > 0) {
inw(base);
byte_count -= 2;
}
}
tty_flip_buffer_push(tty);
}
outw(0x0000, base+0x04); /* enable interrupts */
spin_unlock(&card->card_lock);
return IRQ_HANDLED;
}
static void isicom_config_port(struct isi_port *port)
{
struct isi_board *card = port->card;
struct tty_struct *tty;
unsigned long baud;
unsigned long base = card->base;
u16 channel_setup, channel = port->channel,
shift_count = card->shift_count;
unsigned char flow_ctrl;
tty = port->port.tty;
if (tty == NULL)
return;
/* FIXME: Switch to new tty baud API */
baud = C_BAUD(tty);
if (baud & CBAUDEX) {
baud &= ~CBAUDEX;
/* if CBAUDEX bit is on and the baud is set to either 50 or 75
* then the card is programmed for 57.6Kbps or 115Kbps
* respectively.
*/
/* 1,2,3,4 => 57.6, 115.2, 230, 460 kbps resp. */
if (baud < 1 || baud > 4)
port->port.tty->termios->c_cflag &= ~CBAUDEX;
else
baud += 15;
}
if (baud == 15) {
/* the ASYNC_SPD_HI and ASYNC_SPD_VHI options are set
* by the set_serial_info ioctl ... this is done by
* the 'setserial' utility.
*/
if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
baud++; /* 57.6 Kbps */
if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
baud += 2; /* 115 Kbps */
if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
baud += 3; /* 230 kbps*/
if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
baud += 4; /* 460 kbps*/
}
if (linuxb_to_isib[baud] == -1) {
/* hang up */
drop_dtr(port);
return;
} else
raise_dtr(port);
if (WaitTillCardIsFree(base) == 0) {
outw(0x8000 | (channel << shift_count) | 0x03, base);
outw(linuxb_to_isib[baud] << 8 | 0x03, base);
channel_setup = 0;
switch (C_CSIZE(tty)) {
case CS5:
channel_setup |= ISICOM_CS5;
break;
case CS6:
channel_setup |= ISICOM_CS6;
break;
case CS7:
channel_setup |= ISICOM_CS7;
break;
case CS8:
channel_setup |= ISICOM_CS8;
break;
}
if (C_CSTOPB(tty))
channel_setup |= ISICOM_2SB;
if (C_PARENB(tty)) {
channel_setup |= ISICOM_EVPAR;
if (C_PARODD(tty))
channel_setup |= ISICOM_ODPAR;
}
outw(channel_setup, base);
InterruptTheCard(base);
}
if (C_CLOCAL(tty))
port->port.flags &= ~ASYNC_CHECK_CD;
else
port->port.flags |= ASYNC_CHECK_CD;
/* flow control settings ...*/
flow_ctrl = 0;
port->port.flags &= ~ASYNC_CTS_FLOW;
if (C_CRTSCTS(tty)) {
port->port.flags |= ASYNC_CTS_FLOW;
flow_ctrl |= ISICOM_CTSRTS;
}
if (I_IXON(tty))
flow_ctrl |= ISICOM_RESPOND_XONXOFF;
if (I_IXOFF(tty))
flow_ctrl |= ISICOM_INITIATE_XONXOFF;
if (WaitTillCardIsFree(base) == 0) {
outw(0x8000 | (channel << shift_count) | 0x04, base);
outw(flow_ctrl << 8 | 0x05, base);
outw((STOP_CHAR(tty)) << 8 | (START_CHAR(tty)), base);
InterruptTheCard(base);
}
/* rx enabled -> enable port for rx on the card */
if (C_CREAD(tty)) {
card->port_status |= (1 << channel);
outw(card->port_status, base + 0x02);
}
}
/* open et all */
static inline void isicom_setup_board(struct isi_board *bp)
{
int channel;
struct isi_port *port;
unsigned long flags;
spin_lock_irqsave(&bp->card_lock, flags);
if (bp->status & BOARD_ACTIVE) {
spin_unlock_irqrestore(&bp->card_lock, flags);
return;
}
port = bp->ports;
bp->status |= BOARD_ACTIVE;
for (channel = 0; channel < bp->port_count; channel++, port++)
drop_dtr_rts(port);
spin_unlock_irqrestore(&bp->card_lock, flags);
}
static int isicom_setup_port(struct isi_port *port)
{
struct isi_board *card = port->card;
unsigned long flags;
if (port->port.flags & ASYNC_INITIALIZED)
return 0;
if (tty_port_alloc_xmit_buf(&port->port) < 0)
return -ENOMEM;
spin_lock_irqsave(&card->card_lock, flags);
if (port->port.tty)
clear_bit(TTY_IO_ERROR, &port->port.tty->flags);
if (port->port.count == 1)
card->count++;
port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
/* discard any residual data */
if (WaitTillCardIsFree(card->base) == 0) {
outw(0x8000 | (port->channel << card->shift_count) | 0x02,
card->base);
outw(((ISICOM_KILLTX | ISICOM_KILLRX) << 8) | 0x06, card->base);
InterruptTheCard(card->base);
}
isicom_config_port(port);
port->port.flags |= ASYNC_INITIALIZED;
spin_unlock_irqrestore(&card->card_lock, flags);
return 0;
}
static int block_til_ready(struct tty_struct *tty, struct file *filp,
struct isi_port *port)
{
struct isi_board *card = port->card;
int do_clocal = 0, retval;
unsigned long flags;
DECLARE_WAITQUEUE(wait, current);
/* block if port is in the process of being closed */
if (tty_hung_up_p(filp) || port->port.flags & ASYNC_CLOSING) {
pr_dbg("block_til_ready: close in progress.\n");
interruptible_sleep_on(&port->port.close_wait);
if (port->port.flags & ASYNC_HUP_NOTIFY)
return -EAGAIN;
else
return -ERESTARTSYS;
}
/* if non-blocking mode is set ... */
if ((filp->f_flags & O_NONBLOCK) ||
(tty->flags & (1 << TTY_IO_ERROR))) {
pr_dbg("block_til_ready: non-block mode.\n");
port->port.flags |= ASYNC_NORMAL_ACTIVE;
return 0;
}
if (C_CLOCAL(tty))
do_clocal = 1;
/* block waiting for DCD to be asserted, and while
callout dev is busy */
retval = 0;
add_wait_queue(&port->port.open_wait, &wait);
spin_lock_irqsave(&card->card_lock, flags);
if (!tty_hung_up_p(filp))
port->port.count--;
port->port.blocked_open++;
spin_unlock_irqrestore(&card->card_lock, flags);
while (1) {
raise_dtr_rts(port);
set_current_state(TASK_INTERRUPTIBLE);
if (tty_hung_up_p(filp) || !(port->port.flags & ASYNC_INITIALIZED)) {