[RFC][PATCH] Add NAND lock/unlock routines

[Artem Bityutskiy]

On Mon, 2009-12-07 at 12:18 +0530, Vimal Singh wrote:
> On Fri, Dec 4, 2009 at 2:08 PM, Artem Bityutskiy <dedekind1 at gmail.com> wrote:
> > Hi, some cosmetic comments:
> >
> > On Wed, 2009-12-02 at 19:54 +0530, Vimal Singh wrote:
> >> I am not sure how useful it will be, but still here is a patch for review.
> >> -vimal
> >>
> >> From: Vimal Singh <vimalsingh at ti.com>
> >> Date: Tue, 24 Nov 2009 18:26:43 +0530
> >> Subject: [PATCH] Add NAND lock/unlock routines
> >>
> >> At least 'Micron' NAND parts have lock/unlock feature.
> >> Adding routines for this.
> >>
> >> Signed-off-by: Vimal Singh <vimalsingh at ti.com>
> >> ---
> >>  drivers/mtd/nand/nand_base.c |  217 +++++++++++++++++++++++++++++++++++++++++-
> >>  include/linux/mtd/nand.h     |    6 +
> >>  2 files changed, 221 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
> >> index 2957cc7..e447c24 100644
> >> --- a/drivers/mtd/nand/nand_base.c
> >> +++ b/drivers/mtd/nand/nand_base.c
> >> @@ -757,6 +757,218 @@ static int nand_wait(struct mtd_info *mtd,
> >> struct nand_chip *chip)
> >>  }
> >>
> >>  /**
> >> + * __nand_unlock - [REPLACABLE] unlocks specified locked blockes
> >> + *
> >> + * @param mtd - mtd info
> >> + * @param ofs - offset to start unlock from
> >> + * @param len - length to unlock
> >> + * @invert -  when = 0, unlock the range of blocks within the lower and
> >> + *                      upper boundary address
> >> + *            whne = 1, unlock the range of blocks outside the boundaries
> >> + *                      of the lower and upper boundary address
> >> + *
> >> + * @return - unlock status
> >> + */
> >> +static int __nand_unlock(struct mtd_info *mtd, loff_t ofs,
> >> +                                     uint64_t len, int invert)
> >> +{
> >> +     int ret = 0;
> >> +     int status, page;
> >> +     struct nand_chip *chip = mtd->priv;
> >> +
> >> +     DEBUG(MTD_DEBUG_LEVEL3, "%s: start = 0x%012llx, len = %llu\n",
> >> +                     __func__, (unsigned long long)ofs, len);
> >> +
> >> +     /* Submit address of first page to unlock */
> >> +     page = (int)(ofs >> chip->page_shift);
> >
> > The compiler will automatically cast the result to int I believe.
> 
> I just copied this line from erase functions.
> I believe its better to cast here as otherwise we may see compiler warnings.

Good point. Could you please create a validation checking helper instead
of duplicating code?

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)