[U-Boot] repurposing uboot's console UART after booting

Hi Everybody.
I'm fooling around with a Kindle 3G. I have it setup so I can SSH to it via Wifi, and I can also get a shell through the "accessory port" which happens to be the UART (ttymxc0) that U-Boot uses for console IO.
After booting, I would like to use this UART for other things besides shells and U-Boot status. I want to attach custom peripherals to it instead.
I tried killing the ttymxc0's shell process from my ssh session, but another one pops right up.
In case its not obvious, I'm new to linux, but eager to learn. If possible, I'd rather not rebuild/reinstall U-boot on this device. Instead, I would like to try to make U-Boot release the UART programatically after booting.
Any tips?
Thanks in advance for your help, Craig

On Sat, Apr 23, 2011 at 9:03 PM, CAIannello wrote:
I'm fooling around with a Kindle 3G. I have it setup so I can SSH to it via Wifi, and I can also get a shell through the "accessory port" which happens to be the UART (ttymxc0) that U-Boot uses for console IO.
After booting, I would like to use this UART for other things besides shells and U-Boot status. I want to attach custom peripherals to it instead.
I tried killing the ttymxc0's shell process from my ssh session, but another one pops right up.
In case its not obvious, I'm new to linux, but eager to learn. If possible, I'd rather not rebuild/reinstall U-boot on this device. Instead, I would like to try to make U-Boot release the UART programatically after booting.
this isnt a u-boot issue. once linux boots, u-boot has nothing to do with things. post your question to whoever your distro maker is. -mike

On Sat, Apr 23, 2011 at 06:03:46PM -0700, CAIannello wrote:
After booting, I would like to use this UART for other things besides shells and U-Boot status. I want to attach custom peripherals to it instead.
I tried killing the ttymxc0's shell process from my ssh session, but another one pops right up.
This has nothing to do with U-Boot. Linux typically uses the file /etc/inittab to specify whether to spawn login processes on serial lines. Look at that, along with the Linux man page for "init".

Dear CAIannello,
In message 31463780.post@talk.nabble.com you wrote:
After booting, I would like to use this UART for other things besides shells and U-Boot status. I want to attach custom peripherals to it instead.
I tried killing the ttymxc0's shell process from my ssh session, but another one pops right up.
CXheck /etc/inittab ...
In case its not obvious, I'm new to linux, but eager to learn. If possible, I'd rather not rebuild/reinstall U-boot on this device. Instead, I would like to try to make U-Boot release the UART programatically after booting.
Any tips?
Well, try posting on a mailing list that deals with Linux questions. This issue is in no way related to U-Boot.
Best regards,
Wolfgang Denk
participants (4)
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CAIannello
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Eric Cooper
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Mike Frysinger
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Wolfgang Denk