diff options
Diffstat (limited to 'device')
| -rw-r--r-- | device/pnp_raw.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/device/pnp_raw.c b/device/pnp_raw.c index 1fd7b3bea6b9..653c467ad45f 100644 --- a/device/pnp_raw.c +++ b/device/pnp_raw.c @@ -52,7 +52,8 @@ void rawpnp_exit_ext_func_mode(u16 port) * * This is done by writing the register number to the port, and the value * into port + 1. This code assumes that the data port is always the - * config-port plus 1, but luckily this is true for pretty much all devices. + * config-port plus 1, but luckily this is true for pretty much all devices, since + * it is part of the standard. * * @param port The device I/O port. * @param reg The register number. @@ -65,6 +66,24 @@ void rawpnp_write_config(u16 port, u8 reg, u8 value) } /** + * Read an 8-bit pnp config value + * + * This is done by writing the register number to the port, and the value + * into port + 1. This code assumes that the data port is always the + * config-port plus 1, but luckily this is true for pretty much all devices, since + * it is part of the standard. + * + * @param port The device I/O port. + * @param reg The register number. + * @returns value of the register + */ +u8 rawpnp_read_config(u16 port, u8 reg) +{ + outb(reg, port); + return inb(port + 1); +} + +/** * Select a logical device. * * PNP has up to 16 logical devices. They are selected by writing the |