10.1 USB OTG accessories with 7? sorta.. but need help

[rustyshack3]

I am playing around with the Samsung 30-pin to USB female adapter and the 30-pin to SDHC adapter that my friend bought for her 10.1.

When I plug either of them in, dmesg indicates that an accessory-unknown is connected and online. When I unplug it, dmesg says accessory-unknown is offline.

Now I know from experience in the past with using cell phones as modems back in the good ol' days when there was no such support for Linux, I was able to instantiate the device using some sort of ID and creating a /dev/something for it. Does anyone know about this kind of experimentation? I believe, if I can figure this out, I can make a script for mounting storage connected via these adapters (at least for rooted tabs).



Sent from my Galaxy Cubed tab using Tapatalk.

 

[PBL1]

Do you mean this?

http://forum.xda-developers.com/showthread.php?t=1233072

P

 

[rustyshack3]

Yeah, that's along the same lines, but I am thinking that the GB kernel already basically supports it.

 

[DenimTornado]

I think you are right! USB host is works in 2.3

 

[rustyshack3]

USB OTG actually goes way back. My old Eclair tablet supports it! I think even my Cupcake one before that did too. Just depends on how the kernel is compiled. I think I will try seeing how the dev gets set with the Samsung keyboard, and go from there.

 

[rustyshack3]

Here is a snippet from another forum that shows what I am looking for:

You can look up the specific attributes to match in “/sys/bus/scsi/devices/[devicenumber]/”

When I connect the adapter, dmesg says ... ACCESSORY_ID : ADC value = 2741.
I believe this is the "devicenumber" from above, but I can't find a file with that name anywhere in /sys/bus/*

Still digging. If anyone else wants to join me, this may help.

 

[lardman]

Have you plugged something into the female usb port to get that value?

The message in question comes from Kernel/drivers/misc/30pin_con.c

One interesting line or two in there is the following:

#ifdef CONFIG_USB_S3C_OTG_HOST
		// check USB OTG Host ADC range...
		if(adc_val > 2700 && adc_val < 2799) {
			s3c_usb_cable(USB_OTGHOST_ATTACHED);
		}
#endif

 

[rustyshack3]

Have you plugged something into the female usb port to get that value?

The message in question comes from Kernel/drivers/misc/30pin_con.c

One interesting line or two in there is the following:

#ifdef CONFIG_USB_S3C_OTG_HOST
		// check USB OTG Host ADC range...
		if(adc_val > 2700 && adc_val < 2799) {
			s3c_usb_cable(USB_OTGHOST_ATTACHED);
		}
#endif

Yeah, the value is different if it is just the adapter vs the adapter with a usb device. I have a usb to microSD that I am plugging into the 30-pin to usb adapter.