linux/drivers/tty
Paul Walmsley 197234520b tty: serial: omap-serial: wakeup latency constraint is in microseconds, not milliseconds
The receive FIFO wakeup latency estimate in the omap-serial driver is
three orders of magnitude too small.  This effectively prevents the
MPU from going to a low-power state when CONFIG_CPU_IDLE=y.  This is a
major power management regression and masks some other FIFO-related
bugs in the driver.

Fix by correcting the most egregious problem in the RX wakeup latency
estimate.  There are several other flaws in the estimator; these will
be fixed by a separate patch series intended for 3.4.

The difference in low-power states with this patch can be observed via
debugfs in pm_debug/count.

This estimate does not have any effect when CONFIG_CPU_IDLE=n.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-09 10:48:36 -08:00
..
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 tty: serial: omap-serial: wakeup latency constraint is in microseconds, not milliseconds 2012-02-09 10:48:36 -08:00
vt drivers/tty/vt/vt_ioctl.c: fix KDFONTOP 32bit compatibility layer 2012-02-02 16:11:23 -08:00
Kconfig Merge branch 'for-linus' of git://github.com/richardweinberger/linux 2011-11-02 09:45:39 -07:00
Makefile tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver 2011-08-23 10:32:56 -07:00
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
moxa.c drivers/tty: use printk_ratelimited() instead of printk_ratelimit() 2011-07-01 15:35:45 -07:00
moxa.h tty: move a number of tty drivers from drivers/char/ to drivers/tty/ 2011-02-22 16:14:56 -08:00
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 tty: move a number of tty drivers from drivers/char/ to drivers/tty/ 2011-02-22 16:14:56 -08:00
rocket_int.h tty: move a number of tty drivers from drivers/char/ to drivers/tty/ 2011-02-22 16:14:56 -08:00
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_audit: fix tty_audit_add_data live lock on audit disabled 2011-03-07 12:04:50 -08:00
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