Re: [PATCH net-next v6 8/8] mfd: zl3073x: Register DPLL sub-device during init

[Ivan Vecera]

On 01. 05. 25 3:22 odp., Lee Jones wrote:
> On Wed, 30 Apr 2025, Ivan Vecera wrote:
>
> > Register DPLL sub-devices to expose the functionality provided
> > by ZL3073x chip family. Each sub-device represents one of
> > the available DPLL channels.
> >
> > Signed-off-by: Ivan Vecera <ivecera@xxxxxxxxxx>
> > ---
> > v4->v6:
> > * no change
> > v3->v4:
> > * use static mfd cells
> > ---
> >   drivers/mfd/zl3073x-core.c | 19 +++++++++++++++++++
> >   1 file changed, 19 insertions(+)
> >
> > diff --git a/drivers/mfd/zl3073x-core.c b/drivers/mfd/zl3073x-core.c
> > index 050dc57c90c3..3e665cdf228f 100644
> > --- a/drivers/mfd/zl3073x-core.c
> > +++ b/drivers/mfd/zl3073x-core.c
> > @@ -7,6 +7,7 @@
> >   #include <linux/device.h>
> >   #include <linux/export.h>
> >   #include <linux/math64.h>
> > +#include <linux/mfd/core.h>
> >   #include <linux/mfd/zl3073x.h>
> >   #include <linux/module.h>
> >   #include <linux/netlink.h>
> > @@ -755,6 +756,14 @@ static void zl3073x_devlink_unregister(void *ptr)
> >   	devlink_unregister(ptr);
> >   }
> >   
> > +static const struct mfd_cell zl3073x_dpll_cells[] = {
> > +	MFD_CELL_BASIC("zl3073x-dpll", NULL, NULL, 0, 0),
> > +	MFD_CELL_BASIC("zl3073x-dpll", NULL, NULL, 0, 1),
> > +	MFD_CELL_BASIC("zl3073x-dpll", NULL, NULL, 0, 2),
> > +	MFD_CELL_BASIC("zl3073x-dpll", NULL, NULL, 0, 3),
> > +	MFD_CELL_BASIC("zl3073x-dpll", NULL, NULL, 0, 4),
> > +};
>
> What other devices / subsystems will be involved when this is finished?

Lee, btw. I noticed from another discussion that you mentioned that
mfd_cell->id should not be used outside MFD.

My sub-drivers uses this to get DPLL channel number that should be used
for the particular sub-device.

E.g.
1) MFD_CELL_BASIC("zl3073x-dpll", NULL, NULL, 0, 2);
2) MFD_CELL_BASIC("zl3073x-phc", NULL, NULL, 0, 3);

In these cases dpll_zl3073x sub-driver will use DPLL channel 2 for this
DPLL sub-device and ptp_zl3073x sub-driver will use DPLL channel 3 for
this PHC sub-device.

platform_device->id cannot be used for this purpose in conjunction with
PLATFORM_DEVID_AUTO as that ->id can be arbitrary.

So if I cannot use mfd_cell->id what should I use for that case?
Platform data per cell with e.g. the DPLL channel number?

Thanks for advices...

Ivan