[PATCH v4 0/5] bcm2835: auxiliar device support for spi

Martin Sperl kernel at martin.sperl.org
Wed Aug 26 03:28:29 PDT 2015


On 24.08.2015 10:40, kernel at martin.sperl.org wrote:
> From: Martin Sperl <kernel at martin.sperl.org>
>
> This patch-series implements:
> * the bcm2835-auxiliar device enable/disable api in soc.
> * the bcm2835-auxiliar spi device driver
>
> The uart1 device driver (ns16550 based) is not implemented so far
> but should be using the same API.

As I need to implement another version (see reviews by Stephen)
here a question related to the uart1 and device-tree (as I now got
a compute module to test it)

The uart1 is register-wise compatible with a ns16550, so the
8250 driver can get used almost directly.

Looking at implementations for different platforms I often find:
	compatible = "xlnx,axi-uart16550-1.01.a",
			 "xlnx,xps-uart16550-2.00.a",
			 "ns16550";

Also the foundation kernel does something similar.

The question here is: Would the following device-tree be acceptable?
uart1: uart at 7e215040 {
	...
	compatible = "bcrm,bcm2835-aux-uart", "ns16550";
	brcm,aux-enable = <&aux_enable 1>;
	...
};

So that the driver for "bcrm,bcm2835-aux-uart" would only need to
contain the "probe" and "release" code to enable/disable the HW block.

Is this acceptable or would I need to implement a "more" in depth
driver (so that "ns16550" is not needed in compatiblity) to be accepted
on the device-tree side?

Thanks,
	Martin



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