Do I need a driver to remotely access I2C device on PCIe card?

[Greg KH]

On Sun, Jun 18, 2017 at 07:46:38PM +0000, Nisha Miller wrote:
> Email bounced, so I'm posting again....
> 
> Hi,
> 
> I'm positing this after spending a lot of time googling for a solution and coming up with zilch.
> 
> I have a NVMe SSD PCIe card with an I2C chip on it. I want to read/write to this I2C chip from a remote machine using IPMI (ability to read/write to it locally would be an added bonus but not required).
> 
> When I try to access my card remotely using IPMI (MasterWriteRead) or locally using i2cdetect, I find that SMCLK/SMDAT signals are not generated on these two PCIe pins. For local access, i2c-dev driver is already loaded.
> 
> Do I need a linux driver for my card for remote access via IPMI? Are there are any sample drives I can use as a template?
> 
> I was under the impression that since I2C is a bus, the BMC on the motherboard would talk directly to my I2C device without the need for a driver.

Are you sure that the BMC i2c bus is connected to the i2c bus on your
PCIe card?  I would be _very_ surprised if it really was.

Check your motherboard schematic, odds are what you are trying to do
isn't going to be possible, sorry.

good luck!

greg k-h