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usb_serial: API all change

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USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.

So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.

Longer term we need a proper tty as console abstraction

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alan Cox
2008-07-22 11:09:07 +01:00
committed by Linus Torvalds
parent 1aa3692da5
commit 95da310e66
42 changed files with 1819 additions and 1719 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
drivers/usb/serial/console.c
View File

@@ -145,12 +145,12 @@ static int usb_console_setup(struct console *co, char *options)
}
port = serial->port[0];
port->tty = NULL;
port->port.tty = NULL;
info->port = port;
++port->open_count;
if (port->open_count == 1) {
++port->port.count;
if (port->port.count == 1) {
if (serial->type->set_termios) {
/*
* allocate a fake tty so the driver can initialize
@@ -171,15 +171,15 @@ static int usb_console_setup(struct console *co, char *options)
}
memset(&dummy, 0, sizeof(struct ktermios));
tty->termios = termios;
port->tty = tty;
port->port.tty = tty;
}
/* only call the device specific open if this
* is the first time the port is opened */
if (serial->type->open)
retval = serial->type->open(port, NULL);
retval = serial->type->open(NULL, port, NULL);
else
retval = usb_serial_generic_open(port, NULL);
retval = usb_serial_generic_open(NULL, port, NULL);
if (retval) {
err("could not open USB console port");
@@ -188,9 +188,9 @@ static int usb_console_setup(struct console *co, char *options)
if (serial->type->set_termios) {
termios->c_cflag = cflag;
serial->type->set_termios(port, &dummy);
serial->type->set_termios(NULL, port, &dummy);
port->tty = NULL;
port->port.tty = NULL;
kfree(termios);
kfree(tty);
}
@@ -203,11 +203,11 @@ out:
return retval;
free_termios:
kfree(termios);
port->tty = NULL;
port->port.tty = NULL;
free_tty:
kfree(tty);
reset_open_count:
port->open_count = 0;
port->port.count = 0;
goto out;
}
@@ -227,7 +227,7 @@ static void usb_console_write(struct console *co, const char *buf, unsigned coun
dbg("%s - port %d, %d byte(s)", __func__, port->number, count);
if (!port->open_count) {
if (!port->port.count) {
dbg ("%s - port not opened", __func__);
return;
}
@@ -245,17 +245,17 @@ static void usb_console_write(struct console *co, const char *buf, unsigned coun
}
/* pass on to the driver specific version of this function if it is available */
if (serial->type->write)
retval = serial->type->write(port, buf, i);
retval = serial->type->write(NULL, port, buf, i);
else
retval = usb_serial_generic_write(port, buf, i);
retval = usb_serial_generic_write(NULL, port, buf, i);
dbg("%s - return value : %d", __func__, retval);
if (lf) {
/* append CR after LF */
unsigned char cr = 13;
if (serial->type->write)
retval = serial->type->write(port, &cr, 1);
retval = serial->type->write(NULL, port, &cr, 1);
else
retval = usb_serial_generic_write(port, &cr, 1);
retval = usb_serial_generic_write(NULL, port, &cr, 1);
dbg("%s - return value : %d", __func__, retval);
}
buf += i;
@@ -306,8 +306,8 @@ void usb_serial_console_exit (void)
{
if (usbcons_info.port) {
unregister_console(&usbcons);
if (usbcons_info.port->open_count)
usbcons_info.port->open_count--;
if (usbcons_info.port->port.count)
usbcons_info.port->port.count--;
usbcons_info.port = NULL;
}
}