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geekmaster · 05-27-2012, 10:47 AM

Here is a relevant comment:
http://imxcommunity.org/profiles/blo...-kernel-config
"You may need to customize mx50_arm2_usb_set_vbus(bool enable) in arch/arm/mach-mx5/mx50_rdp.c, so that the OTG driver can turn on the VBUS when the peripheral is attached to the OTG port."

And another related thread:
https://www.mobileread.com/forums/showthread.php?t=47432

They mention a "self-powered hub" (with batteries) to connect multiple USB devices to the OTG port.

It looks like for the nook OTG hack, they flash a custom uImage file (linux kernel). Instead, we could use kexec to boot a uImage custom kernel file from the USB drive.

Here is a list of devices that work (and do not work) on the nook OTG:
https://docs.google.com/spreadsheet/...0OHFhSkE#gid=0

It seems that without external power, you cannot draw more than 100mA from the USB port, and some USB flash sticks need more than that.

The kindle would probably have the same limitations as the nook.

We might be able to add a USB sound dongle to a K4 with the OTG port.

05-27-2012, 10:47 AM	#7
geekmaster Carpe diem, c'est la vie. Posts: 6,433 Karma: 10773670 Join Date: Nov 2011 Location: Multiverse 6627A Device: K1 to PW3	Here is a relevant comment: http://imxcommunity.org/profiles/blo...-kernel-config "You may need to customize mx50_arm2_usb_set_vbus(bool enable) in arch/arm/mach-mx5/mx50_rdp.c, so that the OTG driver can turn on the VBUS when the peripheral is attached to the OTG port." And another related thread: https://www.mobileread.com/forums/showthread.php?t=47432 They mention a "self-powered hub" (with batteries) to connect multiple USB devices to the OTG port. It looks like for the nook OTG hack, they flash a custom uImage file (linux kernel). Instead, we could use kexec to boot a uImage custom kernel file from the USB drive. Here is a list of devices that work (and do not work) on the nook OTG: https://docs.google.com/spreadsheet/...0OHFhSkE#gid=0 It seems that without external power, you cannot draw more than 100mA from the USB port, and some USB flash sticks need more than that. The kindle would probably have the same limitations as the nook. We might be able to add a USB sound dongle to a K4 with the OTG port. Last edited by geekmaster; 05-27-2012 at 11:07 AM.