Hello. Johan Hovold wrote:
I ran the following test: while true; do echo -n "01234567890abcdefghij" >/dev/ttyUSB0; done The data is sent over the serial line with random loss. It occurs because 1. when echo closes ttyUSB0, there's a chance that it cancels the write URB. 2. MCT U232 buffers the last character and acks the USB data before the serial bits are completely sent out. This was originally reported in Red Hat Linux bug #170490. The fix relies on modern facilities drain_delay (approximately the number of bytes outstanding, see case #2 above) and chars_in_buffer. The latter did not account for the last buffer that was removed from the kfifo but not completed yet. I considered it a bug and changed it. The test above works as expected with this patch applied. Signed-off-by: Pete Zaitcev <zaitcev@xxxxxxxxxx> --- drivers/usb/serial/generic.c | 7 +++++-- drivers/usb/serial/mct_u232.c | 3 +++ 2 files changed, 8 insertions(+), 2 deletions(-) This is a resend due to misapplication. Should not fuzz this time! diff -urp -X dontdiff linux-2.6-gregkh/drivers/usb/serial/generic.c linux-2.6-tip/drivers/usb/serial/generic.c --- linux-2.6-gregkh/drivers/usb/serial/generic.c 2010-01-22 13:50:50.433875777 -0700 +++ linux-2.6-tip/drivers/usb/serial/generic.c 2010-01-05 11:32:02.346260069 -0700 @@ -387,10 +387,13 @@ int usb_serial_generic_chars_in_buffer(s dbg("%s - port %d", __func__, port->number);spin_lock_irqsave(&port->lock, flags);- if (serial->type->max_in_flight_urbs) + if (serial->type->max_in_flight_urbs) {Superfluous {.
It's not really. CodingStyle has it that if you have {} on one of the *if* branches, the other branch should also have it.
WBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
