linux/drivers/tty
Rafael J. Wysocki 048be431e4 sh-sci / PM: Avoid deadlocking runtime PM
The runtime PM of sh-sci devices is enabled when sci_probe() returns,
so the pm_runtime_put_sync() executed by driver_probe_device()
attempts to suspend the device.  Then, in some situations, a
diagnostic message is printed to the console by one of the runtime
suspend routines handling the sh-sci device, which causes synchronous
runtime resume to be started from the device's own runtime suspend
callback.  This causes rpm_resume() to be run eventually, which sees
the RPM_SUSPENDING status set by rpm_suspend() and waits for it to
change.  However, the device's runtime PM status cannot change at
that point, because the routine that has set it waits for the
rpm_suspend() to return.  A deadlock occurs as a result.

To avoid that make sci_init_single() increment the device's
runtime PM usage counter, so that it cannot be suspended by
driver_probe_device().  That counter has to be decremented
eventually, so make sci_startup() do that before starting to
actually use the device and make sci_shutdown() increment it
again before returning to balance the incrementation carried out by
sci_startup().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-03-09 12:59:44 +09:00
..
hvc tty: hvc_dcc: Fix duplicate character inputs 2011-11-15 12:02:13 -08:00
ipwireless Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2011-05-24 13:28:35 -07:00
serial sh-sci / PM: Avoid deadlocking runtime PM 2012-03-09 12:59:44 +09:00
vt drivers/tty/vt/vt_ioctl.c: fix KDFONTOP 32bit compatibility layer 2012-02-02 16:11:23 -08:00
amiserial.c TTY: irq: Remove IRQF_DISABLED 2011-09-22 16:08:57 -07:00
bfin_jtag_comm.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
cyclades.c TTY: irq: Remove IRQF_DISABLED 2011-09-22 16:08:57 -07:00
ehv_bytechan.c drivers/tty: don't use the byte channel handle as a parameter in ehv_bytechan.c 2011-09-26 16:38:43 -07:00
isicom.c TTY: irq: Remove IRQF_DISABLED 2011-09-22 16:08:57 -07:00
Kconfig tty/powerpc: early udbg consoles can't be modules 2012-02-24 16:11:50 -08:00
Makefile tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver 2011-08-23 10:32:56 -07:00
moxa.c drivers/tty: use printk_ratelimited() instead of printk_ratelimit() 2011-07-01 15:35:45 -07:00
moxa.h
mxser.c TTY: mxser+cyclades remove wait_until_sent debug code 2011-08-23 10:34:07 -07:00
mxser.h Fix common misspellings 2011-03-31 11:26:23 -03:00
n_gsm.c n_gsm: Fix timings 2011-11-08 10:10:20 -08:00
n_hdlc.c tty: n_hdlc not atomic use tty->flags. 2011-11-30 21:30:49 +09:00
n_r3964.c Revert "tty: make receive_buf() return the amout of bytes received" 2011-06-04 06:33:24 +09:00
n_tracerouter.c n_tracerouter and n_tracesink ldisc additions. 2011-05-13 16:31:00 -07:00
n_tracesink.c n_tracerouter and n_tracesink ldisc additions. 2011-05-13 16:31:00 -07:00
n_tracesink.h n_tracerouter and n_tracesink ldisc additions. 2011-05-13 16:31:00 -07:00
n_tty.c drivers/tty: Remove unneeded spaces 2011-12-09 19:11:35 -08:00
nozomi.c Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2011-05-26 13:19:00 -07:00
pty.c TTY: pty, cleanup the pty counting 2011-11-17 11:42:09 -08:00
rocket.c module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
rocket.h
rocket_int.h
synclink.c module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
synclink_gt.c Fix common misspellings 2011-03-31 11:26:23 -03:00
synclinkmp.c module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
sysrq.c fs: move code out of buffer.c 2012-01-03 22:54:07 -05:00
tty_audit.c
tty_buffer.c tty_buffer: get rid of 'seen_tail' logic in flush_to_ldisc 2011-06-08 07:46:30 -07:00
tty_io.c Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty 2012-01-09 12:09:24 -08:00
tty_ioctl.c tty: Support compat_ioctl get/set termios_locked 2011-10-18 14:17:11 -07:00
tty_ldisc.c Merge 3.2-rc3 into tty-next to handle merge conflict in tty_ldisc.c 2011-11-26 20:07:25 -08:00
tty_mutex.c TTY: remove tty_locked 2011-08-23 10:34:07 -07:00
tty_port.c TTY: fix UV serial console regression 2012-01-24 12:55:37 -08:00