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Diffstat (limited to 'Documentation/arm/SA1100/serial_UART')
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diff --git a/Documentation/arm/SA1100/serial_UART b/Documentation/arm/SA1100/serial_UART new file mode 100644 index 000000000000..aea2e91ca0ef --- /dev/null +++ b/Documentation/arm/SA1100/serial_UART | |||
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| 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 | If you're not using devfs, you must create those inodes in /dev | ||
| 28 | on the root filesystem used 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 | |||
| 47 | |||