Re: [PATCH v2 13/20] nvmem: core: drop priv pointer in post process callback

[Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>]

On 09/09/2022 09:58, Michael Walle wrote:
> Am 2022-09-09 10:52, schrieb Srinivas Kandagatla:
> > On 01/09/2022 23:18, Michael Walle wrote:
> > > It doesn't make any more sense to have a opaque pointer set up by the
> > > nvmem device. Usually, the layout isn't associated with a particular
> > > nvmem device.
> > This is really not a good idea to remove the context pointer, as this
> > is the only way for callback to get context which it can make use of.
>
> In which case? As I mentioned it's the priv to the nvmem driver and all
> the "normal" callbacks can do very little with it. If there will be a
> future need, then there should be a proper opaque pointer associated
> with the layout and not the nvmem driver.

Yes, the opaque object here is the layout priv which I agree with, but 
removing the context totally from the callback is not a good idea.

We should have some context to callbacks to be able to allow them to 
deal with some private info.


--srini

> -michael
>
> > I would prefer this to be left as it is.
> >
> > --srini
> >
> > > Signed-off-by: Michael Walle <michael@xxxxxxxx>
> > > ---
> > > changes since v1:
> > >   - new patch
> > >
> > >   drivers/nvmem/core.c           | 4 ++--
> > >   drivers/nvmem/imx-ocotp.c      | 4 ++--
> > >   include/linux/nvmem-provider.h | 5 +++--
> > >   3 files changed, 7 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
> > > index d31d3f0ab517..6910796937f9 100644
> > > --- a/drivers/nvmem/core.c
> > > +++ b/drivers/nvmem/core.c
> > > @@ -1523,8 +1523,8 @@ static int __nvmem_cell_read(struct 
> > > nvmem_device *nvmem,
> > >           nvmem_shift_read_buffer_in_place(cell, buf);
> > >         if (cell->read_post_process) {
> > > -        rc = cell->read_post_process(nvmem->priv, id, index,
> > > -                         cell->offset, buf, cell->bytes);
> > > +        rc = cell->read_post_process(id, index, cell->offset, buf,
> > > +                         cell->bytes);
> > >           if (rc)
> > >               return rc;
> > >       }
> > > diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c
> > > index ac0edb6398f1..5e869d4a81c5 100644
> > > --- a/drivers/nvmem/imx-ocotp.c
> > > +++ b/drivers/nvmem/imx-ocotp.c
> > > @@ -222,8 +222,8 @@ static int imx_ocotp_read(void *context, unsigned 
> > > int offset,
> > >       return ret;
> > >   }
> > >   -static int imx_ocotp_cell_pp(void *context, const char *id, int 
> > > index,
> > > -                 unsigned int offset, void *data, size_t bytes)
> > > +static int imx_ocotp_cell_pp(const char *id, int index, unsigned int 
> > > offset,
> > > +                 void *data, size_t bytes)
> > >   {
> > >       u8 *buf = data;
> > >       int i;
> > > diff --git a/include/linux/nvmem-provider.h 
> > > b/include/linux/nvmem-provider.h
> > > index 9d22dc5a3fa5..46067a6a0395 100644
> > > --- a/include/linux/nvmem-provider.h
> > > +++ b/include/linux/nvmem-provider.h
> > > @@ -19,8 +19,9 @@ typedef int (*nvmem_reg_read_t)(void *priv, 
> > > unsigned int offset,
> > >   typedef int (*nvmem_reg_write_t)(void *priv, unsigned int offset,
> > >                    void *val, size_t bytes);
> > >   /* used for vendor specific post processing of cell data */
> > > -typedef int (*nvmem_cell_post_process_t)(void *priv, const char *id, 
> > > int index,
> > > -                     unsigned int offset, void *buf, size_t bytes);
> > > +typedef int (*nvmem_cell_post_process_t)(const char *id, int index,
> > > +                     unsigned int offset, void *buf,
> > > +                     size_t bytes);
> > >     enum nvmem_type {
> > >       NVMEM_TYPE_UNKNOWN = 0,