| Mauro Carvalho Chehab | dc7a12b | 2019-04-14 15:51:10 -0300 | [diff] [blame] | 1 | ================== |
| 2 | SA1100 serial port |
| 3 | ================== |
| 4 | |
| 5 | The 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 | |
| 31 | You must create those inodes in /dev on the root filesystem used |
| 32 | by 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 | |
| 41 | In addition to the creation of the appropriate device nodes above, you |
| 42 | must ensure your user space applications make use of the correct device |
| 43 | name. The classic example is the content of the /etc/inittab file where |
| 44 | you might have a getty process started on ttyS0. |
| 45 | |
| 46 | In 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. |