[Gta04-owner] Further 3.17 kernel development for GTA04

[Dr. H. Nikolaus Schaller]

Hi Neil,

Am 09.11.2014 um 16:57 schrieb Neil Jerram <neil at ossau.homelinux.net>:

> Neil Jerram <neil at ossau.homelinux.net> writes:
> 
>> NeilBrown <neilb at suse.de> writes:
>> 
>>> On Wed, 05 Nov 2014 00:22:29 +0000 Neil Jerram <neil at ossau.homelinux.net>
>>> wrote:
>>> 
>>>> What config do you use when building your kernel for GTA04?  I've
>>>> checked out your 3.17-gta04, but don't see any obvious GTA04 configs
>>>> under arch/arm/configs.
>>> 
>>> See below.  I'm in two minds about including this.
>> 
>> Thanks.  After some entertaining diversions (*) I've built and booted
>> this kernel and can report that it seems to solve two other problems
>> that were afflicting my last experiments back in June/July [...]
>> 
>> Thank you!
> 
> Does suspending work correctly for you with this kernel?  I have a
> script that I use with xautolock to suspend automatically, and its log
> indicates an I/O error when it tries to suspend by writing 'mem' to
> /sys/power/state:
> 
>  + echo mem
>  sh: echo: I/O error
> 
> If I try to suspend explicitly from the command line, here's what
> happens:
> 
>  root at neo:~# cat /sys/power/state 
>  freeze mem
>  root at neo:~# echo mem > /sys/power/state 
> 
> The screen has gone blank, and so the phone now appears to have
> suspended.  However, if I just tap the screen, it comes on again, and
> then in the SSH session I see:
> 
>  -bash: echo: write error: Operation not permitted
>  root at neo:~# 
> 
> Are you seeing similar?

You made me curious. So I tried with the 3.18-rc3 kernel:

root at gta04:~# cat /sys/power/state 
freeze mem
root at gta04:~# echo mem >/sys/power/state
[   96.168182] PM: Syncing filesystems ... done.
[  101.833740] Freezing user space processes ... (elapsed 0.003 seconds) done.
[  101.845153] Freezing remaining freezable tasks ... (elapsed 0.003 seconds) done.
[  101.856872] Suspending console(s) (use no_console_suspend to debug)

— here the RS232 console pauses until I tap the screen —

[  101.924255] WWAN suspend
[  101.931518] PM: suspend of devices complete after 51.086 msecs
[  101.955444] PM: late suspend of devices complete after 23.834 msecs
[  101.980072] PM: noirq suspend of devices complete after 24.566 msecs
[  101.980102] Disabling non-boot CPUs ...
[  101.980133] Successfully put all powerdomains to target state
[  101.995391] PM: noirq resume of devices complete after 14.678 msecs
[  102.021606] PM: early resume of devices complete after 23.834 msecs
[  102.027404] GPS resuming 0 0 1
[  102.027496] WWAN resume
[  102.366119] mmc1: error -110 during resume (card was removed?)
[  102.366180] dpm_run_callback(): mmc_bus_resume+0x0/0x70 returns -110
[  102.366241] PM: Device mmc1:0001 failed to resume: error -110
[  102.366302] libertas_sdio mmc1:0001:1: mmc1:0001:1: resume: we're back
[  102.368072] PM: resume of devices complete after 346.313 msecs
[  102.460662] Restarting tasks ... done.
[  102.470001] omapdss DPI: Could not find exact pixel clock. Requested 22153000 Hz, got 22153846 Hz
root at gta04:~# 

The backlight and the red power LED stayed on during “suspend”.

What I don’t know is about the mmc1 errors (I have not checked if WLAN works).
In addition the time needed for syncing filesystems is quite long.

So I don’t see your issue. But this “suspend" may not be a good power down state.
Rather it appears to wake up some parts immediately (except for the console).

BR,
Nikolaus