Hi Gary,

On Sat, 19 Jan 2008 15:55:42 -0500 (EST), Gary Chambers wrote:
> > i2c_smbus_read_word_data() does exist, isn't it what you are looking
> > for? It corresponds to a "read word" transaction in SMBus terminology.
> 
> i2c_smbus_read_word_data() implies (to me, anyway) a required 
> data/command in the transaction.

That's correct, the "read word" SMBus transaction first writes a
"command" byte to the device (typically a register address in the
device) before reading two bytes from it.

>                                   Some of the devices with which we deal 
> apparently cannot tolerate this extra 8 bits on the bus when attempting 
> to read a word from them.  The bus analyzer also indicates those extra 
> bits are present.  I'm doing my work through the dev interface, and our 
> functionality matrix seems to indicate that I cannot use pure I2C.  Any 
> thoughts or insight?  Thanks very much!

Well, reading two bytes from a device directly doesn't correspond to any
SMBus transaction, so if your bus controller doesn't support I2C
messaging, I fear that you're pretty much stuck. What adapter is this?
And what chip are you trying to talk to?

-- 
Jean Delvare

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