[PATCH 0/2] ARM: shmobile: sh73a0 Suspend-to-RAM

Bastian Hecht hechtb at gmail.com
Thu Mar 21 09:31:35 EDT 2013


Here is a patch for shutting down the CPU0 to Power Off mode during
SUSPEND-to-RAM (in which case CPU1 is already shut down to Power Off mode
due to CPU hotplug).

While patch 2/2 implements this, we face some unresolved problems with the
interrupt controller code. See: "[PATCH] input: st1232: Add IRQF_NO_SUSPEND flag"
posted on 14th of February. This problem makes us unable to use the touchscreen
as a wakeup source. I consider patch 2/2 sane in itself though, and we
should consider merging it.

To test Suspend-to-RAM, patch 1/2 is supplied that is a workaround to the problem.

When I use the gpio keys in general (and as wakeup source), I get
------------[ cut here ]------------
WARNING: at drivers/tty/tty_buffer.c:428 flush_to_ldisc+0x44/0x1a0()
tty is NULL
I suppose this is another independent problem to this code.

Side note for future work: On the way to CPUIdle we might want to use
CPUIDLE_FLAG_COUPLED that enables us to coordinate the shutdown of both CPUs.

The patches are based on Simon's renesas/next branch.

Bastian Hecht (2):
  input: st1232: Add IRQF_NO_SUSPEND flag
  ARM: shmobile: sh73a0: Suspend-to-RAM Power Off mode

 arch/arm/mach-shmobile/Makefile              |    2 +-
 arch/arm/mach-shmobile/headsmp-sh73a0.S      |   72 ++++++++++++++++++++++++++
 arch/arm/mach-shmobile/include/mach/common.h |    1 +
 arch/arm/mach-shmobile/pm-sh73a0.c           |   32 ++++++++++--
 arch/arm/mach-shmobile/smp-sh73a0.c          |    2 +-
 drivers/input/touchscreen/st1232.c           |    2 +-
 6 files changed, 104 insertions(+), 7 deletions(-)
 create mode 100644 arch/arm/mach-shmobile/headsmp-sh73a0.S

-- 
1.7.9.5




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