Re: [PATCH v5 0/6] drivers/i2c: Add FSI-attached I2C master algorithm

[Joel Stanley]

On Tue, Aug 15, 2017 at 4:06 PM, Peter Rosin <peda@xxxxxxxxxx> wrote:
> On 2017-07-26 19:13, Eddie James wrote:
>> From: "Edward A. James" <eajames@xxxxxxxxxx>
>>
>> This series adds an algorithm for an I2C master physically located on an FSI
>> slave device. The I2C master has multiple ports, each of which may be connected
>> to an I2C slave. Access to the I2C master registers is achieved over FSI bus.
>>
>> Due to the multi-port nature of the I2C master, the driver instantiates a new
>> I2C adapter for each port connected to a slave. The connected ports should be
>> defined in the device tree under the I2C master device.
>
> Hmmm, AFAIU fsi is a bus, and on this bus you have some "client" device that
> happens to be an i2c master, and this is a driver for that "client". Is it
> totally inconceivable to have some other client device in the future that is
> implementing an i2c master differently, but still using the fsi bus?
>
> With that in mind, is it wise to pick the driver name from the bus that the
> device is connected to, and nothing else without further qualification?
>
> I don't see any "i2c-usb" driver, but I think there are a couple of i2c master
> drivers that communicate via usb.

You make a fair point. When I did a prototype of this driver I called
it i2c-cfam, as it is part of the CFAM hardware unit inside of the
Power8/Power9 processors.

The documentation does call it FSI_I2CM, so that's an argument for the
current name.

I'm not sure how accurate that name is. Chris, Eddie, do you have any
other suggestions?

Cheers,

Joel