[PATCH 3/5] MTD: chips/map_rom.c: implement point and unpoint methods

[Nicolas Pitre]

On Wed, 11 Oct 2017, Richard Weinberger wrote:

> On Wed, Oct 11, 2017 at 5:26 AM, Nicolas Pitre <nicolas.pitre at linaro.org> wrote:
> > Signed-off-by: Nicolas Pitre <nico at linaro.org>
> > ---
> >  drivers/mtd/chips/map_rom.c | 24 ++++++++++++++++++++++++
> >  1 file changed, 24 insertions(+)
> >
> > diff --git a/drivers/mtd/chips/map_rom.c b/drivers/mtd/chips/map_rom.c
> > index e67f73ab44..722afb1cf4 100644
> > --- a/drivers/mtd/chips/map_rom.c
> > +++ b/drivers/mtd/chips/map_rom.c
> > @@ -22,6 +22,10 @@ static struct mtd_info *map_rom_probe(struct map_info *map);
> >  static int maprom_erase (struct mtd_info *mtd, struct erase_info *info);
> >  static unsigned long maprom_unmapped_area(struct mtd_info *, unsigned long,
> >                                           unsigned long, unsigned long);
> > +static int maprom_point (struct mtd_info *mtd, loff_t from, size_t len,
> > +                        size_t *retlen, void **virt, resource_size_t *phys);
> > +static int maprom_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
> > +
> >
> >  static struct mtd_chip_driver maprom_chipdrv = {
> >         .probe  = map_rom_probe,
> > @@ -52,6 +56,8 @@ static struct mtd_info *map_rom_probe(struct map_info *map)
> >         mtd->type = MTD_ROM;
> >         mtd->size = map->size;
> >         mtd->_get_unmapped_area = maprom_unmapped_area;
> > +       mtd->_point = maprom_point;
> > +       mtd->_unpoint = maprom_unpoint;
> >         mtd->_read = maprom_read;
> >         mtd->_write = maprom_write;
> >         mtd->_sync = maprom_nop;
> > @@ -78,6 +84,24 @@ static unsigned long maprom_unmapped_area(struct mtd_info *mtd,
> >  {
> >         struct map_info *map = mtd->priv;
> >         return (unsigned long) map->virt + offset;
> > +
> > +static int maprom_point(struct mtd_info *mtd, loff_t from, size_t len,
> > +                       size_t *retlen, void **virt, resource_size_t *phys)
> > +{
> > +       struct map_info *map = mtd->priv;
> > +
> > +       if (!map->virt)
> > +               return -EINVAL;
> > +       *virt = map->virt + from;
> > +       if (phys)
> > +               *phys = map->phys + from;
> > +       *retlen = len;
> > +       return 0;
> > +}
> > +
> > +static int maprom_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> > +{
> > +       return 0;
> >  }
> 
> Can we please have a generic helper function for un/point instead of
> copy&pasting?

I'd prefer not. In this case (and the mapram case) the point/unpoint 
code is unusuably simple.  I don't want people to think that such 
simpleness is expected by making this into a common or generic function. 
Normally this ought to be more involved (see cfi_cmdset_0001 for 
a real example).


Nicolas