power button doesn't work on Kindle Touch

[silverzhao]

I bought my Kindle Touch on April 2012, and it seems now that power button doesn't work any more on my Kindle Touch, no matter pressing it or holding it for a long time.

I run the command:

# showlog -f

and when I press power button, it is not detected, while pressing HOME button does.

Does this mean there is something wrong on the hardware level, so I have to repair it?

At the time, the main problem is that I can't resume from screensaver state by pressing power button, but have to plug it to a computer. It is so inconvenient.

I've tried running "~ds" in the search bar to disable the screensaver, but doing so would prevent Kindle from entering into suspend mode, which leads to consuming more power.

I get to know from here that command

# powerd_test -p

would simulate power button pressed event, so is it possible to set pressing HOME button to execute this command when in screensaver/suspend mode?

Thanks!

[knc1]

Hardware problem sounds like the best guess from your testing.

As to re-mapping the button ...
Might be possible, but that power button is connected to a special chip that detects the various "hold times" for the power button's special functions.
That (the hardware special functions) would be hard to emulate.

Might have to say it is time to send it to a "Kindle Shop".

[silverzhao]

Originally Posted by knc1

Hardware problem sounds like the best guess from your testing.

As to re-mapping the button ...
Might be possible, but that power button is connected to a special chip that detects the various "hold times" for the power button's special functions.
That (the hardware special functions) would be hard to emulate.

Might have to say it is time to send it to a "Kindle Shop".

Thanks for your reply. What I want is not to re-map Home button to power button, but to not disable it in some way when in screensaver state, and when pressing it this command could be executed:

# powerd_test -p          # simulate power button pressed event

I think eventHandler may be able to do something here in some way, but I don't know how.

So could anyone help?

[knc1]

Originally Posted by silverzhao

Thanks for your reply. What I want is not to re-map Home button to power button, but to not disable it in some way when in screensaver state, and when pressing it this command could be executed:

# powerd_test -p          # simulate power button pressed event

I think eventHandler may be able to do something here in some way, but I don't know how.

So could anyone help?

"When in screensaver state ..." the CPU is halted.
You need a running CPU to execute firmware/software commands.

Sorry, that is just the way it is with these electronic computers, you have to have the CPU running before they work.

You can read the kernel messages associated with it going into 'suspend' and coming out of 'suspend' in the dmseg log (there is a KUAL button for that).

Which, by the way, is one of the "hardware things" that special chip on the power button does - sends a hardware event signal to the SoC that makes it resume the CPU.

The only other, easily accessible, known hardware event the user can create, is a "USB event". Plug (or unplug) a USB device while the CPU is suspended. The change in the hardware configuration will cause the Linux kernel to resume operation.

Note There are some 'states' a Kindle can be put into that causes it to display the screensaver while the CPU is still running.
But in most cases of the screensaver being displayed, the CPU is in a "suspend to ram" state (I.E: shutdown).

[NiLuJe]

It's been a while since I checked how it works in recent devices, but basically, there used to be a two-step timeout process: first timeout => show screensaver, then second timeout => suspend.

[silverzhao]

Thanks for your reply. So I'll have to repair it sometime.

[xpressoz]

Any news on the power button fix?

Mine after a while stop working, i could activate it only by conecting it to a usb and for a while was working after i repeted push the power button and last push was longer then stop working again even with this method, then not wakeup even when i connect it to USB. After 6 month + when he sit in a drawer someone told me that might work if i blow some air in the button and clear the dust that might gather under it.

And now starts the funny part. It seems that the battery was totaly depleted and after a long charge the Kindle touch started to wake up when connected to USB. I say, ok how can blow some air under the button, not haveing some air spray or something like that i blow it with my mouth (jokes on me ) and after two long blows the button started to work normaly, for a while.

And the strange part, after a day i tried the button again and was dead. Blow it again and didnt work imediatley, only a couple of minutes after, again, worked like new. Let it to enter in standby mode and some times wasnt wakeup only after i blew it again.

What i think is that the air having umidity too is creating condensed on the surface of the button and can make normal contact again. Dont know, but is reminding me of those remote control buttons that has the metal dust clean off from the plastic membrane and couldnt make a bridge between the metal lines on the circuit board.

Anybody knows what kind of button it has in there? part number/ type or something.

Let me know if this stupid methond (Thank you Amazon!) works for you too or what could be that this metod triger the button to work normally.

Thank you.