[LinuxBIOS] MCP55 LinuxBIOS with USB debug

Lu, Yinghai yinghai.lu at amd.com
Wed Jan 24 02:16:50 CET 2007

Maybe Nvidia fixed the bug in mcp55. AMD8111 is using DAT0...


It should use SMBHDTCMD for val with send/receive byte.


Serverworks chipset already use CMD.






From: linuxbios-bounces at linuxbios.org
[mailto:linuxbios-bounces at linuxbios.org] On Behalf Of bxshi
Sent: Tuesday, January 23, 2007 5:08 PM
To: Lu, Yinghai
Cc: linuxbios at linuxbios.org
Subject: Re: [LinuxBIOS] MCP55 LinuxBIOS with USB debug



	You may need to use

	smbus_send_byte(hub_address, hub_channel);


	smbus_write_byte(hub_address, hub_channel);



smbus_write_byte may need three parametres, smbus_write_byte(device
,address ,val).

for PCA9545 to enable one channel need four steps ,


1. outb(hub_address, base_io+02)

2. outb(hub_channel, base_io +03)

3. outb(0x04, base_io + 00)

4. test  inb(base_io+01)   


it is a little different from PCA9556/PCA9557. as I look at the code ,
use smbus_write_byte may not make pca9545 work . 

use smbus_send_byte(device,val) , I get the output:


No memory for this cpu

No memory


so I change below

outb(val, smbus_io_base + SMBHSTCMD);

then everything works fine.

so I think smbus_send_byte(device,val) ,device should be the HUB_ADDRESS
, and val is the HUB_CHANNEL. is it right?




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