Re: [PATCH v2 17/18] fpga: dfl: fme: add global error reporting support

[Alan Tull <atull@kernel.org>]

On Mon, Apr 29, 2019 at 4:13 AM Wu Hao <hao.wu@intel.com> wrote:

Hi Hao,

The changes look good.  There's one easy to fix thing that Greg has
pointed out recently on another patch (below).

>
> This patch adds support for global error reporting for FPGA
> Management Engine (FME), it introduces sysfs interfaces to
> report different error detected by the hardware, and allow
> user to clear errors or inject error for testing purpose.
>
> Signed-off-by: Luwei Kang <luwei.kang@intel.com>
> Signed-off-by: Ananda Ravuri <ananda.ravuri@intel.com>
> Signed-off-by: Xu Yilun <yilun.xu@intel.com>
> Signed-off-by: Wu Hao <hao.wu@intel.com>

Acked-by: Alan Tull <atull@kernel.org>

> ---
> v2: fix issues found in sysfs doc.
>     fix returned error code issues for writable sysfs interfaces.
>     (use -EINVAL if input doesn't match error code)
>     reorder the sysfs groups in code.

> +static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
> +                            char *buf)
> +{
> +       struct device *err_dev = dev->parent;
> +       void __iomem *base;
> +
> +       base = dfl_get_feature_ioaddr_by_id(err_dev, FME_FEATURE_ID_GLOBAL_ERR);
> +
> +       return scnprintf(buf, PAGE_SIZE, "%u\n", dfl_feature_revision(base));

Greg is discouraging use of scnprintf for sysfs attributes where it's
not needed [1].

Please fix this up the attributes added in this patchset.  Besides
that, looks good, I added my Ack.

Alan

> +}
> +static DEVICE_ATTR_RO(revision);

[1] https://lkml.org/lkml/2019/4/25/1050