drivers: iio: Adding channels to the simple_dummy module

Hey everyone,

I am trying to get started with the IIO subsystem by doing the following tasks:

https://kernelnewbies.org/IIO_tasks

In task 3, which requires us to add 3 channels to the dummy_device, I have added the structures in the dummy_channels array(which is of type struct chan_spec), similar to the other channels in the dummy_channels array.(in file drivers/iio/dummy/iio_simple_dummy.c)

I also added elements to the enum iio_simple_dummy_scan_elements for the scan_index val.(in iio_simple_dummy.h)

I recompiled the kernel and loaded the modules iio_dummy and iio_dummy_evgen using modprobe.

is the right approach. I am not able to see any new channels being added to my /sys/bus/iio/devices/iio:device0/ directory?

printk is not printing to dmesg. I put printk in the probe function

Quoted 11 lines · Bharath Vedartham

Hey everyone,

I am trying to get started with the IIO subsystem by doing the following tasks:

https://kernelnewbies.org/IIO_tasks

In task 3, which requires us to add 3 channels to the dummy_device, I have added the structures in the dummy_channels array(which is of type struct chan_spec), similar to the other channels in the dummy_channels array.(in file drivers/iio/dummy/iio_simple_dummy.c)

Quoted 8 lines

I also added elements to the enum iio_simple_dummy_scan_elements for the scan_index val.(in iio_simple_dummy.h)

I recompiled the kernel and loaded the modules iio_dummy and iio_dummy_evgen using modprobe.

is the right approach. I am not able to see any new channels being added to my /sys/bus/iio/devices/iio:device0/ directory?

Did you followed the configfs setup as illustrated in the aforementioned link ?

Did the modules got loaded correctly ?

And if you're doing Task 3, I'd assume that the previous tasks were done correctly ?

Quoted 1 line

printk is not printing to dmesg. I put printk in the probe function

Without any logs or diffs, it's hard to predict about where exactly you're doing wrong.

Btw, we do have a IIO mailing list as well:
[email protected]

Signature · 4 lines

Himanshu Jha
Undergraduate Student
Department of Electronics & Communication
Guru Tegh Bahadur Institute of Technology

Thank you for your time. I have started another thread where i have added a diff. I am really not used to using mutt to add diffs,logs in it etc. Please bear with me.

Quoted 3 lines

Thank you for your time. I have started another thread where i have added a diff. I am really not used to using mutt to add diffs,logs in it etc. Please bear with me.

Well, you can try other email clients such as Evolution, Claws ...

There is no rule saying to use Mutt exclusively.

Signature · 4 lines

Himanshu Jha
Undergraduate Student
Department of Electronics & Communication
Guru Tegh Bahadur Institute of Technology

Quoted 3 lines · Himanshu Jha

Well, you can try other email clients such as Evolution, Claws ...

There is no rule saying to use Mutt exclusively.

VM has low RAM. Need to adjust :)

Quoted 6 lines · Bharath Vedartham

Quoted 3 lines · Himanshu Jha

Well, you can try other email clients such as Evolution, Claws ...

There is no rule saying to use Mutt exclusively.

VM has low RAM. Need to adjust :)

Upgrade the hypervisor system so the VM can be properly configured :)

(As a side note, few people send their diffs from inside their test VM. They usually build outside the VM and copy the needed pieces into a shared area that the build environment and the VM can both see.)

Quoted 5 lines · On Fri, Jan 25, 2019 at 11:24:33AM -0500, [email protected] wrote:

Quoted 1 line · Bharath Vedartham

VM has low RAM. Need to adjust :)

Upgrade the hypervisor system so the VM can be properly configured :)

I think I ll rather build a native version. The reason I chose a VM was cause I was told that if I break the kernel it would be much safer. But I think GRUB will save my life if I screw things up. Thanks for your time!

Quoted 3 lines

(As a side note, few people send their diffs from inside their test VM. They usually build outside the VM and copy the needed pieces into a shared area that the build environment and the VM can both see.)

That is an interesting usecase. I wonder why they need to do that?