Information is unavailable on "Clocks", "Sensors" and "Gpio" pages in powerdebug with Samsung Arndale Android.

[Botao]

On Samsung Arndale board with Linaro Android image:

https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.03-release/#build=1

The output realtime information is unavailable on "Clocks", "Sensors" and "Gpio" columns.

For the bug on ARM Versatile Express A9, please refer to:

https://bugs.launchpad.net/linaro-powerdebug/+bug/1229658

###########################################
This issue is observed on following images:
https://android-build.linaro.org/builds/~linaro-android/linux-linaro-arndale/#build=386
https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.03-release/#build=1
https://android-build.linaro.org/builds/~linaro-android/linux-linaro-arndale/#build=415
https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.04-release/#build=1
https://android-build.linaro.org/builds/~linaro-android/linux-linaro-arndale/#build=447
https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.05-release/#build=1
https://android-build.linaro.org/builds/~linaro-android/linux-linaro-arndale/#build=473
https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.06-release/#build=1
https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.07-release/#build=1

[Mohammad Merajul Islam Molla (meraj-enigma)]

I tested powerdebug version 0.7.1 using Linaro arndale-saucy_server 14.03. Gpio's information is missing in output. Error message on command prompt is as below -

error: unable to open directory /sys/class/gpio
failed to initialize gpios

$ ls /sys/class/gpio
ls: cannot access /sys/class/gpio: No such file or directory

I am using Samsung Arndale Board wih Exynos 5250 (Cortex-A15).

[Mohammad Merajul Islam Molla (meraj-enigma)]

I compiled the kernel with CONFIG_GPIO_SYSFS=y. This creates the entry /sys/class//gpio.

Now if I run 'sudo powerdebug' it does not display the error message above, but it still fails to show gpio information.

[sanjay singh rawat (sanjay-rawat)]

- The /sys/kernel/debug directory is missing, the debugfs support is missing in the arndale kernel i think.

[sanjay singh rawat (sanjay-rawat)]

- I checked in arndale android (4.4) kernel (3.9.1) directives needed for powerdebug are not enabled. Directives DEBUG_FS, GPIO_SYSFS and HWMON are needed.

[Amit Kucheria (amitk)]

Thanks for checking. In any case, powerdebug shouldn't error out if one or more of the information sources aren't present. Instead, on each tab, it should say which are the kernel config options typically required for information to be present for that tab.

e.g. on GPIO tab, if /sys/class/gpio is missing, just print "Typically, CONFIG_GPIO_SYSFS, CONFIG_FOO, etc. are need for this feature. Please ensure they are compiled into your kernel"

[Mohammad Merajul Islam Molla (meraj-enigma)]

In addition to my comment (#2), I further checked and noticed that for powerdebug to display gpio information, the GPIO first has to be exported to userspace by writing the GPIO number in /sys/class/gpio/export file.

May be some warning message can be added in addition to printing the message in comment (#5), to avoid user surprise.

[sanjay singh rawat (sanjay-rawat)]

On Wednesday 23 April 2014 12:56 AM, Soumya Basak wrote:
> ** Description changed:
>
> On Samsung Arndale board with Linaro Android image:
>
> https://android-build.linaro.org/builds/~linaro-android/arndale-
> linaro-14.03-release/#build=1
>
> The output realtime information is unavailable on "Clocks", "Sensors"
> and "Gpio" columns.
>
> For the bug on ARM Versatile Express A9, please refer to:
>
> https://bugs.launchpad.net/linaro-powerdebug/+bug/1229658
>
> #################################
> This issue is observed on following images:
> https://android-build.linaro.org/builds/~linaro-android/linux-linaro-arndale/#build=386
> https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.03-release/#build=1
> https://android-build.linaro.org/builds/~linaro-android/linux-linaro-arndale/#build=415
> + https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.04-release/#build=1
>

Botao & Soumya first the support needs to be enbaled in Arndale kernel,
powerdebug will not work untill support is there. Still from my side i
have updated the prerequisites in readme and sent a patch(under review)
to display error info. please reassign to Arndale kernel team. thanks

[Botao (botao-sun)]

On Samsung Arndale 5250 board with Linaro Android 14.06 release image:

https://android-build.linaro.org/builds/~linaro-android/arndale-linaro-14.06-release/#build=1

When run powerdebug, it shows:

Empty in Clock column;

error: path /sys/class/hwmon not found in Sensors column;

error: path /sys/class/gpio not found in Gpio column.

[Botao (botao-sun)]

Checked, those stuff doesn't exist under the /sys/class directory:

root@arndale:/sys/class # ls
ata_device
ata_link
ata_port
bdi
block
dma
firmware
graphics
i2c-adapter
input
mdio_bus
mem
misc
mmc_host
net
regulator
scsi_device
scsi_disk
scsi_generic
scsi_host
thermal
timed_output
tty
udc
vc
video4linux
vtconsole