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Based on kernel version 3.15.4. Page generated on 2014-07-07 08:59 EST.

1	The SA1100 serial port had its major/minor numbers officially assigned:
2	
3	> Date: Sun, 24 Sep 2000 21:40:27 -0700
4	> From: H. Peter Anvin <hpa@transmeta.com>
5	> To: Nicolas Pitre <nico@CAM.ORG>
6	> Cc: Device List Maintainer <device@lanana.org>
7	> Subject: Re: device
8	> 
9	> Okay.  Note that device numbers 204 and 205 are used for "low density
10	> serial devices", so you will have a range of minors on those majors (the
11	> tty device layer handles this just fine, so you don't have to worry about
12	> doing anything special.)
13	> 
14	> So your assignments are:
15	> 
16	> 204 char        Low-density serial ports
17	>                   5 = /dev/ttySA0               SA1100 builtin serial port 0
18	>                   6 = /dev/ttySA1               SA1100 builtin serial port 1
19	>                   7 = /dev/ttySA2               SA1100 builtin serial port 2
20	> 
21	> 205 char        Low-density serial ports (alternate device)
22	>                   5 = /dev/cusa0                Callout device for ttySA0
23	>                   6 = /dev/cusa1                Callout device for ttySA1
24	>                   7 = /dev/cusa2                Callout device for ttySA2
25	>
26	
27	You must create those inodes in /dev on the root filesystem used
28	by your SA1100-based device:
29	
30		mknod ttySA0 c 204 5
31		mknod ttySA1 c 204 6
32		mknod ttySA2 c 204 7
33		mknod cusa0 c 205 5
34		mknod cusa1 c 205 6
35		mknod cusa2 c 205 7
36	
37	In addition to the creation of the appropriate device nodes above, you
38	must ensure your user space applications make use of the correct device
39	name. The classic example is the content of the /etc/inittab file where
40	you might have a getty process started on ttyS0.  In this case:
41	
42	- replace occurrences of ttyS0 with ttySA0, ttyS1 with ttySA1, etc.
43	
44	- don't forget to add 'ttySA0', 'console', or the appropriate tty name
45	  in /etc/securetty for root to be allowed to login as well.
46	
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