4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tobias Herzog <t-herzog@xxxxxx> commit f976d0e5747ca65ccd0fb2a4118b193d70aa1836 upstream. The usb standard ("Universal Serial Bus Class Definitions for Communication Devices") distiguishes between "consistent signals" (DSR, DCD), and "irregular signals" (break, ring, parity error, framing error, overrun). The bits of "irregular signals" are set, if this error/event occurred on the device side and are immeadeatly unset, if the serial state notification was sent. Like other drivers of real serial ports do, just the occurence of those events should be counted in serial_icounter_struct (but no 1->0 transitions). Signed-off-by: Tobias Herzog <t-herzog@xxxxxx> Acked-by: Oliver Neukum <oneukum@xxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/class/cdc-acm.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -332,17 +332,17 @@ static void acm_ctrl_irq(struct urb *urb if (difference & ACM_CTRL_DSR) acm->iocount.dsr++; - if (difference & ACM_CTRL_BRK) - acm->iocount.brk++; - if (difference & ACM_CTRL_RI) - acm->iocount.rng++; if (difference & ACM_CTRL_DCD) acm->iocount.dcd++; - if (difference & ACM_CTRL_FRAMING) + if (newctrl & ACM_CTRL_BRK) + acm->iocount.brk++; + if (newctrl & ACM_CTRL_RI) + acm->iocount.rng++; + if (newctrl & ACM_CTRL_FRAMING) acm->iocount.frame++; - if (difference & ACM_CTRL_PARITY) + if (newctrl & ACM_CTRL_PARITY) acm->iocount.parity++; - if (difference & ACM_CTRL_OVERRUN) + if (newctrl & ACM_CTRL_OVERRUN) acm->iocount.overrun++; spin_unlock(&acm->read_lock);