[PATCH 09/19] ARM: ux500: Enable SSP (SPI) for HREF when booting Device Tree

Roland Stigge stigge at antcom.de
Mon Sep 17 13:03:20 EDT 2012


Hi!

On 09/10/2012 01:11 PM, Linus Walleij wrote:
> +SPI slave nodes must be children of the SPI master node and can
> +contain the following properties.
> +
> +- pl022,interface : interface type:
> +       0: SPI
> +       1: Texas Instruments Synchronous Serial Frame Format
> +       2: Microwire (Half Duplex)
> +- pl022,com-mode : polling, interrupt or dma
> +- pl022,rx-level-trig : Rx FIFO watermark level
> +- pl022,tx-level-trig : Tx FIFO watermark level
> +- pl022,ctrl-len : Microwire interface: Control length
> +- pl022,wait-state : Microwire interface: Wait state
> +- pl022,duplex : Microwire interface: Full/Half duplex
> 
> Currently this is defined as auxdata in board-mop500.c
> but notanly cs-gpios (num chipselects) should come from
> device tree instead.
> 
> It appears Roland has written his bindings such that DT
> data augments platform data (yes, I am also getting crazy
> about this prioritization, mea culpa for ACKing this without
> proper discussion) so it appears that you could actually
> use AUXDATA and some stuff in the DT at the same
> time.

Sorry for the incompleteness of the devicetree conversion. I'm sending a
patch (separately) that makes it possible to specify everything via
devicetree, so you can choose between dt and platform data.

Except in case of callback specification (dma_filter()), you need to
provide platform data.

Interestingly, when I removed the actual platform data from the board
file, I noticed that I still needed to specify a device name (like
dev:ssp0) to make it work. But this seems to be expected according to
the documentation of OF_DEV_AUXDATA(). Are there any plans or ideas how
to fix this?

When we have sorted out this driver change (please check the new pl022
specific dt property names!), I will provide patches for arm-soc to
actually use this new interface via dts files.

Thanks in advance,

Roland



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