08-12-2012, 04:06 PM | #1 |
Basculocolpic
Posts: 4,356
Karma: 20181319
Join Date: Jul 2010
Location: Sweden
Device: Kindle 3 WiFi, Kindle 4SO, Kindle for Android, Sony PRS-350 and PRS-T1
|
OTG support
This is one of the fora I don't visit often because it flies right above my scalp. But i was hoping someone here could tell me if it is possible to get host capabilities for the USB connector on a K3.
I am thinking that by connecting an OTG to the micro USB with a regular female USB connector on the other end I might be able to connect a keyboard or Bluetooth dongle. Probably overly optimistic, but maybe there is some hack that can be applied. |
08-12-2012, 04:54 PM | #2 | |
Going Viral
Posts: 17,212
Karma: 18210809
Join Date: Feb 2012
Location: Central Texas
Device: No K1, PW2, KV, KOA
|
Quote:
You should be able to use a OTG **HOST** micro USB cable and manually do the remove and install of the kernel modules required to switch from device to host operation. Amazon does sell such an adapter - listed for the K4 and the K5, without mention of the K3. Another note - The power available from the Kindle's OTG port may be less (maybe much less) than what can be expected from a standard USB port - since they did not build the hardware to by used this way. Translation: Use a powered hub to provide power to the external devices. Let us know how you get on with this - This subject has come up here before. |
|
Advert | |
|
08-12-2012, 05:13 PM | #3 |
Basculocolpic
Posts: 4,356
Karma: 20181319
Join Date: Jul 2010
Location: Sweden
Device: Kindle 3 WiFi, Kindle 4SO, Kindle for Android, Sony PRS-350 and PRS-T1
|
I did a search but nothing i could see seemed relevant. Sorry if I'm regurgitating something that is already established. Another reason why a silly girl is reluctant to approach this fora.
|
08-12-2012, 05:19 PM | #4 |
Official Lurker
Posts: 1,050
Karma: 7096675
Join Date: Apr 2012
Device: Kindle 3.4
|
I think what heis trying to say is that this subject has comup before, but it will be interesting to see what you come up with. I, for one, are very interested to see if this could work.
|
08-12-2012, 05:36 PM | #5 |
Going Viral
Posts: 17,212
Karma: 18210809
Join Date: Feb 2012
Location: Central Texas
Device: No K1, PW2, KV, KOA
|
|
Advert | |
|
08-12-2012, 06:47 PM | #6 |
Carpe diem, c'est la vie.
Posts: 6,433
Karma: 10773668
Join Date: Nov 2011
Location: Multiverse 6627A
Device: K1 to PW3
|
The Nook Simple Touch has similar hardware and has a forum here. Perhaps the OTG tools from it could be used here too. For the NST they use a custom kernel I think, but we can also load one using kexec (from a thread here).
You also need to port device drivers for the various devices you plan to install, such as USB mass storage, USB keyboard, USB sound (for K4), USB mouse, USB bluetooth, etc. You may also need to write code that knows how to traverse a USB hub. Some of this may be portable from android or debian linux repositories, but some may need custom drivers. It just takes somebody with enough interest and time to dedicate to it. Last edited by geekmaster; 08-12-2012 at 07:01 PM. |
08-12-2012, 06:51 PM | #7 |
Official Lurker
Posts: 1,050
Karma: 7096675
Join Date: Apr 2012
Device: Kindle 3.4
|
I believe seaniko7's kernel does kexec.(sorry, i can't find you a link, 'm posting from my kindle 3)
|
08-13-2012, 02:44 AM | #8 | |
Basculocolpic
Posts: 4,356
Karma: 20181319
Join Date: Jul 2010
Location: Sweden
Device: Kindle 3 WiFi, Kindle 4SO, Kindle for Android, Sony PRS-350 and PRS-T1
|
Quote:
I'd post here what I'd be willing to do to anyone who came up with a solution, but then I'd be banned from the board. |
|
08-13-2012, 04:38 AM | #9 | |
Going Viral
Posts: 17,212
Karma: 18210809
Join Date: Feb 2012
Location: Central Texas
Device: No K1, PW2, KV, KOA
|
Quote:
I even ordered (from Amazon) the adapter cable to do it with when cscat and I posted about doing this a few months ago. |
|
08-13-2012, 04:45 AM | #10 |
Basculocolpic
Posts: 4,356
Karma: 20181319
Join Date: Jul 2010
Location: Sweden
Device: Kindle 3 WiFi, Kindle 4SO, Kindle for Android, Sony PRS-350 and PRS-T1
|
Forgive my ignorance but the Kindle runs some flavor of Linux as its kernel, right ? To me that sounds like there is a lot of flexibility in customization.
|
08-13-2012, 06:25 AM | #11 |
Wizard
Posts: 1,379
Karma: 2155307
Join Date: Nov 2010
Location: Goettingen, Germany
Device: Kindle Paperwhite, Kobo Mini
|
Indeed it is. And I partly agree with knc1 about nearly all things already present. However, with USB OTG the important bit is - besides of course a HCI (host controller interface) - the correct switching logic. I short skimming through the kernel source seems to indicate that some (probably untested) support is already in place.
Also, Hardware will play a role. While the data lines might be driven by a charge pump on 5V levels, I doubt so for the VCC line. But then, this is highly untested grounds. A USB hub (self-powered) might rectify the voltage/current parts here, as was mentioned in this thread before. However, it's not just some end-user config option in the kernel, I think. That's also due to the platform: The kernel was patched to fit it and when patching a kernel to fit a platform like the Kindle, it is highly uncommon to bring in more - including more options - than the developers need to. Unfortunately. |
08-13-2012, 06:50 AM | #12 |
Basculocolpic
Posts: 4,356
Karma: 20181319
Join Date: Jul 2010
Location: Sweden
Device: Kindle 3 WiFi, Kindle 4SO, Kindle for Android, Sony PRS-350 and PRS-T1
|
You don't think the developers might have thought "it'd be nice if I could type with an external keyboard on this device“?
|
08-13-2012, 07:13 AM | #13 |
Wizard
Posts: 1,379
Karma: 2155307
Join Date: Nov 2010
Location: Goettingen, Germany
Device: Kindle Paperwhite, Kobo Mini
|
Nah, I think they thought "well, what were the guys over at Freescale thinking?!?". For which the answer probably is "well, when is the contractor finally done with the last missing bits so we can sell that stuff?!?".
|
08-13-2012, 07:17 AM | #14 |
Basculocolpic
Posts: 4,356
Karma: 20181319
Join Date: Jul 2010
Location: Sweden
Device: Kindle 3 WiFi, Kindle 4SO, Kindle for Android, Sony PRS-350 and PRS-T1
|
Yeah, that's probably closer to the mundane reality of code creating, guess I'm a tad naive and optimistic.
|
08-13-2012, 09:51 AM | #15 | |
Carpe diem, c'est la vie.
Posts: 6,433
Karma: 10773668
Join Date: Nov 2011
Location: Multiverse 6627A
Device: K1 to PW3
|
Quote:
Here is a little test I just did on my K5: [root@kindle root]# modprobe ehci-hcd otg [root@kindle root]# dmesg|tail usbcore: registered new device driver usb ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver fsl-ehci fsl-ehci.1: Freescale On-Chip EHCI Host Controller fsl-ehci fsl-ehci.1: new USB bus registered, assigned bus number 1 fsl-ehci fsl-ehci.1: irq 14, io base 0x53f80200 fsl-ehci fsl-ehci.1: USB 2.0 started, EHCI 1.00 usb usb1: configuration #1 chosen from 1 choice hub 1-0:1.0: USB hub found hub 1-0:1.0: 1 port detected [root@kindle root]# According to "FreescaleUSBDrivers.pdf", the next step is to plug in a USB drive and check dmesg again. I plugged in a USB stick, but the power LED did not turn on and no now message was added to dmesg. It would be interesting to see if it is detected when external power is supplied. This would be easier to test by using an onscreen console or a wifi SSH connection, to avoid switching between USB ethernet gadget and other USB gadgets. Later in the manual is says to do "modprobe g_file_storage file=/dev/ram0" to mount a USB drive. Searching for it on my K5 found this: ./lib/modules/2.6.31-rt11-lab126/kernel/drivers/usb/gadget/g_file_storage.ko So like I said, it just takes SOMEBODY who is interested enough to devote the time to do this research. I did not say that it was HARD. I just provided a list of things that need to be taken into account, and may need to be added IF any of them are missing. The little extra research I just did shows that the K5 appears to have built-in support for USB storage devices over OTG. Cool. It is easier to to tell others they are wrong without providing useful information to support that claim, than it is to do a little research to provide the information. It is not hard. I never said it was. I just provided a list of possibilities to be researched, and now I started a path of research others can follow. Although a bit old, here is the document I used: FreescaleUSBDrivers.pdf: http://www.mobileread.mobi/forums/at...9&d=1256815731 Also, traversing USB hubs is not necessarily supported by all OTG devices, and would also require software support. Not all USB devices work when attached to a hub (from lack of software support). I just stripped the outer insulation from part of one of my USB OTG host cables, and I plan to attach the power wires from another USB cable to it so I can borrow power from a USB wall charger or host computer. I do not have time to continue this now -- TTYL... Last edited by geekmaster; 08-13-2012 at 10:19 AM. |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
USB OTG on Sony PRS-T1? scam? | bercoo | Sony Reader | 15 | 04-04-2013 09:58 AM |
Experiments with USB-OTG | HarryT | Android Devices | 13 | 07-03-2012 03:55 PM |
Support officially outsourced to Phillippines (paid support) | larka | enTourage eDGe | 5 | 06-08-2011 12:48 AM |
Is Astak support on vacation or just stopped support? | dmikov | Astak EZReader | 9 | 01-22-2010 01:43 PM |
USB OTG | Mythic | Bookeen | 7 | 11-11-2007 12:39 PM |