Re: [PATCH] i3c: remove 'const' from FIFO helpers

[Geert Uytterhoeven]

CC sparclinux, arnd

On Fri, 8 Aug 2025 at 01:09, Alexandre Belloni
<alexandre.belloni@xxxxxxxxxxx> wrote:
> On 07/08/2025 06:31:24+0200, Wolfram Sang wrote:
> > As buildbot reports, some architectures do not want const pointers.
> >
> > Fixes: 733b439375b4 ("i3c: master: Add inline i3c_readl_fifo() and i3c_writel_fifo()")
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > Closes: https://lore.kernel.org/oe-kbuild-all/202508070438.TZZA3f2S-lkp@xxxxxxxxx/
> > Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> > ---
> >
> > I still wonder why SPARC discards the const but since nobody seems to be
> > commenting on that, I guess the fastest way to get the build error out
> > of Linus' tree is to adapt the usage in I3C.
>
> My plan was to let sparc people handle their mess, there is no reason
> const should be discarded.

Fully agreed.

Note that it is not just the const keyword that is missing from the
SPARC implementation, but also the volatile keyword.

> > --- a/drivers/i3c/internals.h
> > +++ b/drivers/i3c/internals.h
> > @@ -30,8 +30,7 @@ void i3c_dev_free_ibi_locked(struct i3c_dev_desc *dev);
> >   * @buf: Pointer to the data bytes to write
> >   * @nbytes: Number of bytes to write
> >   */
> > -static inline void i3c_writel_fifo(void __iomem *addr, const void *buf,
> > -                                int nbytes)
> > +static inline void i3c_writel_fifo(void __iomem *addr, void *buf, int nbytes)
> >  {
> >       writesl(addr, buf, nbytes / 4);
> >       if (nbytes & 3) {
> > @@ -48,8 +47,7 @@ static inline void i3c_writel_fifo(void __iomem *addr, const void *buf,
> >   * @buf: Pointer to the buffer to store read bytes
> >   * @nbytes: Number of bytes to read
> >   */
> > -static inline void i3c_readl_fifo(const void __iomem *addr, void *buf,
> > -                               int nbytes)
> > +static inline void i3c_readl_fifo(void __iomem *addr, void *buf, int nbytes)
> >  {
> >       readsl(addr, buf, nbytes / 4);
> >       if (nbytes & 3) {
> > --
> > 2.47.2

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds