kernel.git/drivers/usb/serial/generic.c, branch linux-2.6.32.y

USB: serial: handle Data Carrier Detect changes

2011-02-17T23:36:44Z

commit d14fc1a74e846d7851f24fc9519fe87dc12a1231 upstream. Alan's commit 335f8514f200e63d689113d29cb7253a5c282967 introduced .carrier_raised function in several drivers. That also means tty_port_block_til_ready can now suspend the process trying to open the serial port when Carrier Detect is low and put it into tty_port.open_wait queue. We need to wake up the process when Carrier Detect goes high and trigger TTY hangup when CD goes low. Some of the devices do not report modem status line changes, or at least we don't understand the status message, so for those we remove .carrier_raised again. Signed-off-by: Libor Pechacek Signed-off-by: Greg Kroah-Hartman

usb: serial: fix memory leak in generic driver

2010-01-25T18:49:29Z

commit 2591530204a76fecc843529ade56afe865dd2657 upstream. Fix a regression introduced by commit 715b1dc01fe44537e8fce9566e4bb48d6821d84b ("USB: usb_debug, usb_generic_serial: implement multi urb write"). URB transfer buffer was never freed when using multi-urb writes. Currently the only driver enabling multi-urb writes is usb_debug. Signed-off-by: Johan Hovold Cc: Greg KH Acked-by: Jason Wessel Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

USB: Fix throttling in generic usbserial driver

2009-10-09T20:52:08Z

The generic usbserial driver in Linux 2.6.31 halts its receiving channel in response to throttle requests from the line discipline. Unfortunately it drops the contents of the first URB received after throttling takes effect. This patch corrects that problem. Signed-off-by: Joris van Rantwijk Acked-by: Johan Hovold Cc: stable Signed-off-by: Greg Kroah-Hartman

USB: use kfifo to buffer usb-generic serial writes

2009-09-23T13:46:34Z

When do_output_char() attempts to write a carriage return/line feed sequence, it first checks to see how much buffer room is available. If there are at least two characters free, it will write the carriage return/line feed with two calls to tty_put_char(). It calls the tty_operation functions write() for devices that don't support the tty_operations function put_char(). If the USB generic serial device's write URB is not in use, it will return the buffer size when asked how much room is available. The write() of the carriage return will cause it to mark the write URB busy, so the subsequent write() of the line feed will be ignored. This patch uses the kfifo infrastructure to implement a write FIFO that accurately returns the amount of space available in the buffer. Signed-off-by: David VomLehn Signed-off-by: Greg Kroah-Hartman

tty: USB does not need the filp argument in the drivers

2009-09-19T20:13:26Z

And indeed none of them use it. Clean this up as it will make moving to a standard open method rather easier. Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

tty: Fix USB kref leak

2009-07-11T02:17:22Z

The sysrq code acquired a kref leak. Fix it by passing the tty separately from the caller (thus effectively using the callers kref which all the callers hold anyway) Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

tty: Sort out the USB sysrq changes that wrecked performance

2009-07-11T02:17:22Z

We can't go around calling all sorts of magic per character functions at full rate 3G data speed. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds

USB: usb-serial: replace shutdown with disconnect, release

2009-06-16T04:44:47Z

This patch (as1254) splits up the shutdown method of usb_serial_driver into a disconnect and a release method. The problem is that the usb-serial core was calling shutdown during disconnect handling, but drivers didn't expect it to be called until after all the open file references had been closed. The result was an oops when the close method tried to use memory that had been deallocated by shutdown. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: usb_serial: only allow sysrq on a console port

2009-06-16T04:44:47Z

The only time a sysrq should get processed is if the attached device is a console. This is intended to protect sysrq execution on a host connected with a terminal program. Here is the problem scenario: host A <-- rs232 link --> host B Host A is using mincom and a usb pl2303 device to connect to host b which is a linux system with a usb pl2303 device acting as the serial console. When host B is rebooted the pl2303 emits random junk characters on reset. These character sequences contain serial break signals most of the time and when translated to a sysrq have caused host A to get random processes killed, reboots or power down. It is true that in this setup with this patch host B might still have the same problem as host A if you reboot host A. In most cases host A is a development host which seldom gets rebooted, and you could turn off sysrq temporarily on host B if you need to reboot host A. Signed-off-by: Jason Wessel Signed-off-by: Greg Kroah-Hartman

USB: serial: usb_debug,usb_generic_serial: implement sysrq and serial break

2009-06-16T04:44:45Z

The usb_debug driver was modified to implement serial break handling by using a "magic" data packet comprised of the sequence: 0x00 0xff 0x01 0xfe 0x00 0xfe 0x01 0xff When the tty layer requests a serial break the usb_debug driver sends the magic packet. On the receiving side the magic packet is thrown away or a sysrq is activated depending on what kernel .config options have been set. The generic serial driver was modified as well as the usb serial headers to generically implement sysrq processing in the same way the non usb uart based drivers implement the sysrq handling. This will allow other usb serial devices to implement sysrq handling as desired. The new usb serial functions are named similarly and implemented similarly to the uart functions as follows: usb_serial_handle_break <-> uart_handle_break usb_serial_handle_sysrq_char <-> uart_handle_sysrq_char Signed-off-by: Jason Wessel Signed-off-by: Greg Kroah-Hartman