projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| cc2a2d19 MCC |
1 | =================================== |
| 2 | Berkshire Products PC Watchdog Card | |
| 3 | =================================== | |
| 4 | ||
| 4d389dce AC |
5 | Last reviewed: 10/05/2007 |
| 6 | ||
| cc2a2d19 MCC |
7 | Support for ISA Cards Revision A and C |
| 8 | ======================================= | |
| 9 | ||
| 10 | Documentation and Driver by Ken Hollis <kenji@bitgate.com> | |
| 1da177e4 LT |
11 | |
| 12 | The PC Watchdog is a card that offers the same type of functionality that | |
| 13 | the WDT card does, only it doesn't require an IRQ to run. Furthermore, | |
| 14 | the Revision C card allows you to monitor any IO Port to automatically | |
| 15 | trigger the card into being reset. This way you can make the card | |
| 16 | monitor hard drive status, or anything else you need. | |
| 17 | ||
| 18 | The Watchdog Driver has one basic role: to talk to the card and send | |
| 19 | signals to it so it doesn't reset your computer ... at least during | |
| 20 | normal operation. | |
| 21 | ||
| 22 | The Watchdog Driver will automatically find your watchdog card, and will | |
| 23 | attach a running driver for use with that card. After the watchdog | |
| 4d389dce AC |
24 | drivers have initialized, you can then talk to the card using a PC |
| 25 | Watchdog program. | |
| 1da177e4 LT |
26 | |
| 27 | I suggest putting a "watchdog -d" before the beginning of an fsck, and | |
| 28 | a "watchdog -e -t 1" immediately after the end of an fsck. (Remember | |
| 29 | to run the program with an "&" to run it in the background!) | |
| 30 | ||
| 31 | If you want to write a program to be compatible with the PC Watchdog | |
| 56fb9e53 | 32 | driver, simply use of modify the watchdog test program: |
| 718d50ec | 33 | tools/testing/selftests/watchdog/watchdog-test.c |
| 1da177e4 | 34 | |
| 1da177e4 LT |
35 | |
| 36 | Other IOCTL functions include: | |
| 37 | ||
| 38 | WDIOC_GETSUPPORT | |
| 39 | This returns the support of the card itself. This | |
| 40 | returns in structure "PCWDS" which returns: | |
| cc2a2d19 | 41 | |
| 1da177e4 LT |
42 | options = WDIOS_TEMPPANIC |
| 43 | (This card supports temperature) | |
| 44 | firmware_version = xxxx | |
| 45 | (Firmware version of the card) | |
| 46 | ||
| 47 | WDIOC_GETSTATUS | |
| 48 | This returns the status of the card, with the bits of | |
| 49 | WDIOF_* bitwise-anded into the value. (The comments | |
| 37826187 | 50 | are in include/uapi/linux/watchdog.h) |
| 1da177e4 LT |
51 | |
| 52 | WDIOC_GETBOOTSTATUS | |
| 53 | This returns the status of the card that was reported | |
| 54 | at bootup. | |
| 55 | ||
| 56 | WDIOC_GETTEMP | |
| 57 | This returns the temperature of the card. (You can also | |
| 58 | read /dev/watchdog, which gives a temperature update | |
| 59 | every second.) | |
| 60 | ||
| 61 | WDIOC_SETOPTIONS | |
| 62 | This lets you set the options of the card. You can either | |
| 63 | enable or disable the card this way. | |
| 64 | ||
| 65 | WDIOC_KEEPALIVE | |
| 66 | This pings the card to tell it not to reset your computer. | |
| 67 | ||
| 68 | And that's all she wrote! | |
| 69 | ||
| 70 | -- Ken Hollis | |
| 71 | (kenji@bitgate.com) |