Re: [PATCH 00/10] spi: Add driver to support AMD eSPI controller

[Rangoju, Raju]

On 3/26/2025 4:35 PM, Mark Brown wrote:
> On Wed, Mar 26, 2025 at 03:25:21PM +0530, Rangoju, Raju wrote:
> > On 3/17/2025 7:44 PM, Mark Brown wrote:
>
> > > I see nothing in this series that registers a SPI controller with the
> > > SPI core.  You need to use the standard frameworks the kernel offers to
> > > provide standard functionality.
>
> > The AMD SPI controller hardware has only the chip select line enabled, which
> > is connected to the EC slave in AMD EMB platforms. Currently, there is no
> > support from the slave device to register as an SPI slave device with the
> > SPI framework and provide SPI communication.
>
> > For this reason, the AMD eSPI driver is designed to handle device
> > initialization itself and provide a character device file as an interface
> > with user space for dynamic interaction and configurations.
>
> If you want to ignore the SPI subsystem and just write a driver for your
> embedded controller then you should put the driver in the subsystem or
> subsystems for that embedded controller (possibly MFD if it does a bunch
> of things), not SPI.  Even if there is no flexibility you may still want
> to have the controller side in the SPI subsystem in order to help with
> reuse with different controller/EC combinations but if you're going that
> way you need to use the SPI subsystem.

Thanks for the suggestions Mark. We will rework on this.