On 02/06/2015 at 19:04:35 +0200, Boris Brezillon wrote :

Hi Cyrille,

On Tue, 2 Jun 2015 18:57:19 +0200
Cyrille Pitchen [off-list ref] wrote:

quoted

This driver supports the new Atmel Flexcom. The Flexcom is a wrapper which
integrates one SPI controller, one I2C controller and one USART. Only one
function can be enabled at a time. This driver selects the function once for
all, when the Flexcom is probed, according to the value of the new
"atmel,flexcom-mode" device tree property.

This driver has chosen to present the Flexcom to the system as a clock so the
implementation is seamless for the existing Atmel SPI, I2C and USART drivers.

Could detail a bit more why you chose to represent this flexcom IP as
a clock device ?

I don't like to use this 'DT should represent real hardware' argument,
but to me, it looks like you're trying to use a false hardware
representation to avoid changing the peripheral drivers code, which is
wrong since the DT is supposed to represent the hardware blocks.

How about representing the flexcom as an MFD instead ?

It should probably be represented as an MFD. The MFD driver will parse
the chosen configuration and the probe the correct driver. You can have
a look at the recent ST LPC driver from Lee.


-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com