Re: [PATCH v2 2/5] reset: socfpga: use the reset-simple driver

From: Philipp Zabel
Date: Fri Aug 11 2017 - 12:50:50 EST


Hi Alexandru,

thank you for the comments.

On Fri, 2017-08-11 at 09:28 -0700, Alexandru Gagniuc wrote:
> Hi Phillip,
>
> On 08/11/2017 06:06 AM, Philipp Zabel wrote:
> [snip]
>
> > @@ -113,8 +137,33 @@ static int reset_simple_probe(struct platform_device *pdev)
> > > > Â data->rcdev.ops = &reset_simple_ops;
> > > > Â data->rcdev.of_node = dev->of_node;
> >
> > > > - if (devdata)
> > + if (devdata == &reset_simple_socfpga) {
>
> This sort of special-case handling opens the gate to adding special-caseÂ
> handling for any new device, which somewhat defeats the purpose of aÂ
> generic driver.

That is why I initially only unified the reset ops and not the whole
platorm driver.

I could partially revert this latest change and keep the reset-socfpga
driver, just reusing the reset-simple ops to avoid potential "quirk
creep" in the reset-simple driver.

Or I could drop the #reset-cells warning below and just read the
altr,modrst-offset property for any reset controller, to avoid the
special-case.

> > + u32 modrst_offset;
> > +
> > > > + /*
> > > > + Â* The binding was mainlined without the required property.
> > > > + Â* Do not continue, when we encounter an old DT.
> > > > + Â*/
> > > > + if (!of_find_property(dev->of_node, "#reset-cells", NULL)) {
> > > > + dev_err(dev, "%pOF missing #reset-cells property\n",
> > > > + dev->of_node);
> > > > + return -EINVAL;
> > > > + }
>
> Is the check still required in this context, sinceÂ
> (devm_)reset_control_get() complains really loudly if #reset-cells isÂ
> missing?

I'm fine with removing this. Ideally, this is something that the device
tree compiler should check already.

> > +
> > > > + if (of_property_read_u32(dev->of_node, "altr,modrst-offset",
> > > > + Â&modrst_offset)) {
> > > > + dev_warn(dev, "missing altr,modrst-offset property, assuming 0x10!\n");
> > > > + modrst_offset = 0x10;
> > + }
>
> This can be a generic "reg-offset" property. If and until theÂ
> devicetrees are updated, "altr,modrst-offset" would also have to be readÂ
> as an alternative.

Possibly. Adding new device tree bindings is a separate discussion.

> Since a platform data already exists,Âreset_simple_devdata could be a
> better place to store the default offsetÂof 0x10 for socfpga.

I'll change this as you suggest.

regards
Philipp