Re: [PATCH v2 2/4] dfl: add dfl bus support to MODULE_DEVICE_TABLE()

From: Xu Yilun
Date: Tue Sep 15 2020 - 01:24:04 EST


On Tue, Sep 15, 2020 at 12:08:38PM +0800, Wu, Hao wrote:
> > On Tue, Sep 15, 2020 at 11:27:51AM +0800, Xu Yilun wrote:
> > > Device Feature List (DFL) is a linked list of feature headers within the
> > > device MMIO space. It is used by FPGA to enumerate multiple sub features
> > > within it. Each feature can be uniquely identified by DFL type and
> > > feature id, which can be read out from feature headers.
> > >
> > > A dfl bus helps DFL framework modularize DFL device drivers for different
> > > sub features. The dfl bus matches its devices and drivers by DFL type and
> > > feature id.
> > >
> > > This patch add dfl bus support to MODULE_DEVICE_TABLE() by adding info
> > > about struct dfl_device_id in devicetable-offsets.c and add a dfl entry
> > > point in file2alias.c.
> > >
> > > Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
> > > Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx>
> > > Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
> > > Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> > > Acked-by: Wu Hao <hao.wu@xxxxxxxxx>
>
> Yilun,
>
> I haven't acked-by this patch as it doesn't modify any dfl files, ideally you

Sorry, I misunderstood your comments "Acked-by: xxx for DFL related changes after
this fix".

> need acked-by from real maintainer of scripts/mod code, right?

Ideally yes. From the MAINTAINERS it is Masahiro Yamada, I added him on the "to"
list. But I see some other patches (also for devtable entries) in kernel
don't have his acked-by.

Hi Moritz:

Do you have any ideas on that?

Thanks,
Yilun.

>
> Thanks
> Hao
>
> > > ---
> > > v2: add comments for the format of modalias
> > > ---
> > > scripts/mod/devicetable-offsets.c | 4 ++++
> > > scripts/mod/file2alias.c | 17 +++++++++++++++++
> > > 2 files changed, 21 insertions(+)
> > >
> > > diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-
> > offsets.c
> > > index 27007c1..d8350ee 100644
> > > --- a/scripts/mod/devicetable-offsets.c
> > > +++ b/scripts/mod/devicetable-offsets.c
> > > @@ -243,5 +243,9 @@ int main(void)
> > > DEVID(mhi_device_id);
> > > DEVID_FIELD(mhi_device_id, chan);
> > >
> > > +DEVID(dfl_device_id);
> > > +DEVID_FIELD(dfl_device_id, type);
> > > +DEVID_FIELD(dfl_device_id, feature_id);
> > > +
> > > return 0;
> > > }
> > > diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
> > > index 2417dd1..9fd2e60 100644
> > > --- a/scripts/mod/file2alias.c
> > > +++ b/scripts/mod/file2alias.c
> > > @@ -1368,6 +1368,22 @@ static int do_mhi_entry(const char *filename,
> > void *symval, char *alias)
> > > return 1;
> > > }
> > >
> > > +/* Looks like: dfl:tNfN */
> > > +static int do_dfl_entry(const char *filename, void *symval, char *alias)
> > > +{
> > > +DEF_FIELD(symval, dfl_device_id, type);
> > > +DEF_FIELD(symval, dfl_device_id, feature_id);
> > > +
> > > +/*
> > > + * type contains 4 valid bits and feature_id contains 12 valid bits
> > > + * according to DFL specification.
> > > + */
> > > +sprintf(alias, "dfl:t%01Xf%03X", type, feature_id);
> > > +
> > > +add_wildcard(alias);
> > > +return 1;
> > > +}
> > > +
> > > /* Does namelen bytes of name exactly match the symbol? */
> > > static bool sym_is(const char *name, unsigned namelen, const char
> > *symbol)
> > > {
> > > @@ -1442,6 +1458,7 @@ static const struct devtable devtable[] = {
> > > {"tee", SIZE_tee_client_device_id, do_tee_entry},
> > > {"wmi", SIZE_wmi_device_id, do_wmi_entry},
> > > {"mhi", SIZE_mhi_device_id, do_mhi_entry},
> > > +{"dfl", SIZE_dfl_device_id, do_dfl_entry},
> > > };
> > >
> > > /* Create MODULE_ALIAS() statements.
> > > --
> > > 2.7.4
> > >
> > Applied to for-next,
> >
> > Thanks