Re: [PATCH 1/4] iommu: Resolve fwspec ops automatically

From: Andy Shevchenko
Date: Mon Apr 22 2024 - 01:01:39 EST


Fri, Apr 19, 2024 at 05:55:59PM +0100, Robin Murphy kirjoitti:
> There's no real need for callers to resolve ops from a fwnode in order
> to then pass both to iommu_fwspec_init() - it's simpler and more sensible
> for that to resolve the ops itself. This in turn means we can centralise
> the notion of checking for a present driver, and enforce that fwspecs
> aren't allocated unless and until we know they will be usable.
>
> Also we've grown a generic fwnode_handle_get() since this code was first
> written, so may as well clear up that ugly mismatch while we're in here.

..

> +++ b/drivers/iommu/mtk_iommu_v1.c

> if (!fwspec) {
> - ret = iommu_fwspec_init(dev, &args->np->fwnode, &mtk_iommu_v1_ops);
> + ret = iommu_fwspec_init(dev, &args->np->fwnode);

I'm wondering, while at it, if can avoid direct dereference of fwnode by using of_fwnode_handle().

> if (ret)
> return ret;

..

> +++ b/drivers/iommu/of_iommu.c

> - ret = iommu_fwspec_init(dev, fwnode, ops);
> + ret = iommu_fwspec_init(dev, &iommu_spec->np->fwnode);

Ditto.

> + if (ret == -EPROBE_DEFER)
> + return driver_deferred_probe_check_state(dev);
> if (ret)
> return ret;

..

> --- a/drivers/iommu/tegra-smmu.c
> +++ b/drivers/iommu/tegra-smmu.c

> - err = iommu_fwspec_init(dev, &dev->of_node->fwnode, ops);
> + err = iommu_fwspec_init(dev, &dev->of_node->fwnode);

Ditto.

> if (err < 0) {
> dev_err(dev, "failed to initialize fwspec: %d\n", err);
> return err;

--
With Best Regards,
Andy Shevchenko