Re: [PATCH v2 2/2] spi: octeon: Add thunderx driver

From: David Daney
Date: Mon Aug 01 2016 - 18:38:56 EST


On 08/01/2016 11:49 AM, Mark Brown wrote:
On Mon, Aug 01, 2016 at 11:31:43AM -0700, David Daney wrote:
On 08/01/2016 10:28 AM, Mark Brown wrote:
On Thu, Jul 28, 2016 at 10:31:44AM +0200, Jan Glauber wrote:

+ p->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(p->clk))
+ goto out_unmap;

We're now just using the normal clock API which is good but I'm now
unclear what is going to ensure that the clock is there - is there some
other change elsewhere that I'm not aware of?

The clock is an integral part of the SoC and is always running, so it will
always be there. All we want to know is the frequency, which is supplied by
the device tree clock-bindings framework

So there's something there that registers the clock?

Yes, when using OF device tree, standard device probing registers the clock.

What is that thing on ACPI systems?

I don't know if it works ACPI, or if ACPI even has support for the clock framework. But does it matter? We are not currently using ACPI on systems where this driver is used.

In the future, if we ever need ACPI support, we will add support for it.

David.