1. 24 8月, 2011 3 次提交
    • J
      TTY: serial, remove BTM from wait_until_sent · 1f33a51d
      Jiri Slaby 提交于
      During the BKL removal process, the BKL was switched to tty_lock
      (BTM). Now we should start pruning the BTM further. Let's start with
      wait_until_sent of the serial layer. This will allow us to switch to
      the tty port helpers and thus clean it up much.
      
      In wait_until_sent there are some uport members accessed, but neither
      of them is protected by BTM at the location they are set ('=>' means
      function call):
      * uport->fifosize (set in tty_ioctl => uart_ioctl => uart_set_info)
      * uport->type (set in add_one_port prior to tty_register_device)
      * uport->timeout (set usually in tty_ioctl => tty_mode_ioctl =>
        tty_set_termios => uart_set_termios => uart_change_speed =>
        uport->ops->set_termios => uart_update_timeout)
      * call to uport->ops->tx_empty()
      
      If the tx_empty hook needs some lock to protect accesses to registers,
      it should take &uport->lock spinlock like 8250 does. Otherwise there
      still might be races e.g. with ISRs.
      
      This should also fix the issue Andreas is seeing (BTM in comparison to
      BKL doesn't have any hidden functionality like unlocking during
      sleeping).
      Signed-off-by: NJiri Slaby <jslaby@suse.cz>
      References: https://lkml.org/lkml/2011/5/25/562
      Cc: Alan Cox <alan@linux.intel.com>
      Acked-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Andreas Bombe <aeb@debian.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      1f33a51d
    • E
      drivers/tty/synclink: remove double comment · ae8dbd3e
      Edwin van Vliet 提交于
      Redundant comment line was removed
      Signed-off-by: NEdwin van Vliet <edwin@cheatah.nl>
      Reviewed-by: NJesper Juhl <jj@chaosbits.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      ae8dbd3e
    • T
      tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver · dcd83aaf
      Timur Tabi 提交于
      The ePAPR embedded hypervisor specification provides an API for "byte
      channels", which are serial-like virtual devices for sending and receiving
      streams of bytes.  This driver provides Linux kernel support for byte
      channels via three distinct interfaces:
      
      1) An early-console (udbg) driver.  This provides early console output
      through a byte channel.  The byte channel handle must be specified in a
      Kconfig option.
      
      2) A normal console driver.  Output is sent to the byte channel designated
      for stdout in the device tree.  The console driver is for handling kernel
      printk calls.
      
      3) A tty driver, which is used to handle user-space input and output.  The
      byte channel used for the console is designated as the default tty.
      Signed-off-by: NTimur Tabi <timur@freescale.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      dcd83aaf
  2. 23 8月, 2011 3 次提交
  3. 22 8月, 2011 3 次提交
  4. 21 8月, 2011 4 次提交
  5. 20 8月, 2011 8 次提交
  6. 19 8月, 2011 19 次提交