On 8/15/17 3:10 AM, Joel Stanley wrote:
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?
The I2C engine up to now has been always accessed via the FSI bus so
historically I assume that's why its labelled as FSI_I2CM in the p8/p9
specs. There isn't any reason this I2C device couldn't be implemented
in some other topology independent of FSI / CFAMs. In other words there
are no FSI details internal to this I2C engine, an argument for removing
the 'FSI' tag.
Thanks,
Chris
Cheers,
Joel
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
