[PATCH 0/7] USB: serial: add wait_until_sent-support

[Johan Hovold <jhovold@gmail.com>]

These patches add wait_until_sent-support to usb-serial, which removes
the need to check hardware buffers in chars_in_buffer.

This fixes a problem in ftdi_sio (since 3.7) where select or TIOCMOUTQ
would take much longer than before due the hardware buffers being
queried.

Hardware buffers are also currently checked in chars_in_buffer in io_ti
(since 3.8) and ti_usb_3410_5052 (in 3.10).

Note that simply removing the hardware-buffer checks (e.g. for the
stable trees) would break tty_wait_until_sent, which is used, for
instance, by tcdrain, tcsendbreak, and close.

Johan


Johan Hovold (7):
  USB: serial: add wait_until_sent operation
  USB: serial: add generic wait_until_sent implementation
  USB: ftdi_sio: clean up get_modem_status
  USB: ftdi_sio: fix chars_in_buffer overhead
  USB: io_ti: fix chars_in_buffer overhead
  USB: ti_usb_3410_5052: fix chars_in_buffer overhead
  USB: serial: clean up chars_in_buffer

 drivers/usb/serial/ftdi_sio.c         | 28 +++++++++-------------------
 drivers/usb/serial/generic.c          | 29 +++++++++++++++++++++++++++++
 drivers/usb/serial/io_ti.c            | 22 ++++++++++++++--------
 drivers/usb/serial/ti_usb_3410_5052.c | 23 +++++++++++++++--------
 drivers/usb/serial/usb-serial.c       | 30 +++++++++++++++++++++---------
 include/linux/usb/serial.h            |  4 ++++
 6 files changed, 92 insertions(+), 44 deletions(-)

-- 
1.8.2.1