serial_uart.rst (1932B)
1================== 2SA1100 serial port 3================== 4 5The SA1100 serial port had its major/minor numbers officially assigned:: 6 7 > Date: Sun, 24 Sep 2000 21:40:27 -0700 8 > From: H. Peter Anvin <hpa@transmeta.com> 9 > To: Nicolas Pitre <nico@CAM.ORG> 10 > Cc: Device List Maintainer <device@lanana.org> 11 > Subject: Re: device 12 > 13 > Okay. Note that device numbers 204 and 205 are used for "low density 14 > serial devices", so you will have a range of minors on those majors (the 15 > tty device layer handles this just fine, so you don't have to worry about 16 > doing anything special.) 17 > 18 > So your assignments are: 19 > 20 > 204 char Low-density serial ports 21 > 5 = /dev/ttySA0 SA1100 builtin serial port 0 22 > 6 = /dev/ttySA1 SA1100 builtin serial port 1 23 > 7 = /dev/ttySA2 SA1100 builtin serial port 2 24 > 25 > 205 char Low-density serial ports (alternate device) 26 > 5 = /dev/cusa0 Callout device for ttySA0 27 > 6 = /dev/cusa1 Callout device for ttySA1 28 > 7 = /dev/cusa2 Callout device for ttySA2 29 > 30 31You must create those inodes in /dev on the root filesystem used 32by your SA1100-based device:: 33 34 mknod ttySA0 c 204 5 35 mknod ttySA1 c 204 6 36 mknod ttySA2 c 204 7 37 mknod cusa0 c 205 5 38 mknod cusa1 c 205 6 39 mknod cusa2 c 205 7 40 41In addition to the creation of the appropriate device nodes above, you 42must ensure your user space applications make use of the correct device 43name. The classic example is the content of the /etc/inittab file where 44you might have a getty process started on ttyS0. 45 46In this case: 47 48- replace occurrences of ttyS0 with ttySA0, ttyS1 with ttySA1, etc. 49 50- don't forget to add 'ttySA0', 'console', or the appropriate tty name 51 in /etc/securetty for root to be allowed to login as well.