Re: [PATCH V3 2/2] nvmem: add generic driver for devices with MMIO access

[Rafał Miłecki]

On 2023-02-20 20:55, Randy Dunlap wrote:
> On 2/20/23 09:49, Rafał Miłecki wrote:
> > +static int mmio_nvmem_write(void *context, unsigned int offset, void 
> > *val, size_t bytes)
> > +{
> > +	struct mmio_nvmem *priv = context;
> > +
> > +	switch (priv->io_width) {
> > +	case 1:
> > +	case 2:
> > +	case 4:
> > +		return -EOPNOTSUPP;
>
> I'm just curious: (since read supports those cases)
>
> what size writes are typically used here?
> And what value for priv->io_width?

Sorry, I really don't have any statistics on this or any real overview
of hardware that supports MMIO writes. It's probably a minority of
devices that allows it.