Hi. This series enable the PPS reporting for USB serial devices. Patch 01 : change the interface of handle_dcd_change for usb serial in order to avoid duplicating code when calling this function and to be closer of the uart handle_dcd_change interface. Patch 02 : this patch depends on the previous one. It is optional. It restores the way the tty is retreived : the serial drivers used to call tty_port_tty_get as opposed to the uart handle_dcd_change implementation that simply get port->tty. As i don't know wich way you prefer... Patch 03 : this patch add the handling of dcd_change in the ftdi driver. Patch 04 : this patch add the callback to the line discipline dcd_change handler. Patch 05 : this patch is optional. While reading the code i've found that wake_up_interruptible was often called after status processing (ch341, 8250, ...). So i suggest to move this one. This patchset have been tested with a pl2303 device and ftdi device. These devices coupled to the usb serial stack introduce latencies. I think that the jitter may depend on devices, and I'm not even sure it is constant. But the PPS reporting works and allows to play with it. Thank for your comments. Cheers. Paul. Paul Chavent (5): USB : serial : remove tty arg of handle_dcd_change. USB : serial : get protected tty in handle_dcd_change. USB : serial : call handle_dcd_change in ftdi driver. USB : serial : invoke dcd_change ldisc's handler. USB : serial : pl2303 wake up after dcd status check. drivers/usb/serial/ch341.c | 7 ++----- drivers/usb/serial/ftdi_sio.c | 5 ++++- drivers/usb/serial/generic.c | 13 +++++++++++-- drivers/usb/serial/pl2303.c | 11 +++-------- include/linux/usb/serial.h | 1 - 5 files changed, 20 insertions(+), 17 deletions(-) -- 1.7.12.1 -- 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