Re: [PATCH v1 1/5] siox: new driver framework for eckelmann SIOX

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, Dec 07, 2017 at 10:30:04AM +0100, Uwe Kleine-König wrote:
> SIOX is a bus system invented at Eckelmann AG to control their building
> management and refrigeration systems. Traditionally the bus was
> implemented on custom microcontrollers, today Linux based machines are
> in use, too.
> 
> The topology on a SIOX bus looks as follows:
> 
>       ,------->--DCLK-->---------------+----------------------.
>       ^                                v                      v
>  ,--------.                ,----------------------.       ,------
>  |        |                |   ,--------------.   |       |
>  |        |--->--DOUT-->---|->-|shift register|->-|--->---|
>  |        |                |   `--------------'   |       |
>  | master |                |        device        |       |  device
>  |        |                |   ,--------------.   |       |
>  |        |---<--DIN---<---|-<-|shift register|-<-|---<---|
>  |        |                |   `--------------'   |       |
>  `--------'                `----------------------'       `------
>       v                                ^                      ^
>       `----------DLD-------------------+----------------------'
> 
> There are two control lines (DCLK and DLD) driven from the bus master to
> all devices in parallel and two daisy chained data lines, one for input
> and one for output. DCLK is the clock to shift both chains by a single
> bit. On an edge of DLD the devices latch both their input and output
> shift registers.
> 
> This patch adds a framework for this bus type.

Oops, you forgot a Documentation/ABI/ patch for all of the new sysfs
files you are creating here.

Also, why use kernfs direct nodes?  That feels "odd" to me.

thanks,

greg k-h