mmc: add wp_grp_size node

From: "lin.gui" <lin.gui@mediatek.com>

Detail:
Add node "wp_grp_size", corresponding to WP_GRP_SIZE
(write protect group size) of eMMC's CSD register.

Scenario:
The eMMC card can be set into write-protected mode to
prevent data from being accidentally modified or deleted.
Wp_grp_size (Write Protect Group Size) refers to an
attribute of the eMMC card, used to manage write protection,
and is the CSD register  [36:32] of the eMMC device.
Wp_grp_size (Write Protect Group Size) indicates how many
eMMC blocks are contained in each write protection group on the eMMC card.

Final rendered file:
"/sys/class/mmc_host/mmc0/mmc0:0001/wp_grp_size"

Signed-off-by: lin.gui <lin.gui@mediatek.com>
Change-Id: I73952dbde2db375ba918daadb3264380b7863096
---
 drivers/mmc/core/mmc.c   | 16 +++++++++++++++-
 include/linux/mmc/card.h |  2 ++
 2 files changed, 17 insertions(+), 1 deletion(-)

On Fri, 2023-11-03 at 09:27 +0100, AngeloGioacchino Del Regno wrote:
> Il 01/11/23 16:49, Bo Ye ha scritto:
> > From: "lin.gui" <lin.gui@mediatek.com>
> > 
> > Detail:
> > Add node "wp_grp_size", corresponding to WP_GRP_SIZE
> > (write protect group size) of eMMC's CSD register.
> > 
> > Scenario:
> > The eMMC card can be set into write-protected mode to
> > prevent data from being accidentally modified or deleted.
> > Wp_grp_size (Write Protect Group Size) refers to an
> > attribute of the eMMC card, used to manage write protection,
> > and is the CSD register  [36:32] of the eMMC device.
> > Wp_grp_size (Write Protect Group Size) indicates how many
> > eMMC blocks are contained in each write protection group on the
> > eMMC card.
> > 
> > Final rendered file:
> > "/sys/class/mmc_host/mmc0/mmc0:0001/wp_grp_size"
> > 
> > Signed-off-by: lin.gui <lin.gui@mediatek.com>
> 
> The change-id tag means nothing upstream. Please remove.
  Removed change-id, thanks for your patience. I will run
scripts/check-patch.pl before uploading patch next time.
> 
> Also, the recipients list doesn't look right. Please use
> scripts/get_maintainer.pl
> to get the right recipients list, or your patch will be ignored.
  Could you help share who is the maintainers of mmc. The recipients
list was generated by scripts/get_maintainer.pl.
> 
> > ---
> >   drivers/mmc/core/mmc.c   | 16 +++++++++++++++-
> >   include/linux/mmc/card.h |  2 ++
> >   2 files changed, 17 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> > index 4a4bab9aa726..9b67e49a9e63 100644
> > --- a/drivers/mmc/core/mmc.c
> > +++ b/drivers/mmc/core/mmc.c
> > @@ -136,6 +136,17 @@ static void mmc_set_erase_size(struct mmc_card
> > *card)
> >   	mmc_init_erase(card);
> >   }
> > 
> > +static void mmc_set_wp_grp_size(struct mmc_card *card)
> > +{
> > +	if (card->ext_csd.erase_group_def & 1)
> > +		card->wp_grp_size = card->ext_csd.hc_erase_size *
> > +			card->ext_csd.raw_hc_erase_gap_size;
> > +	else
> > +		card->wp_grp_size = card->csd.erase_size *
> > +			(card->csd.wp_grp_size + 1);
> > +}
> > +
> >   /*
> >    * Given a 128-bit response, decode to our card CSD structure.
> >    */
> > @@ -186,6 +197,7 @@ static int mmc_decode_csd(struct mmc_card
> > *card)
> >   		b = UNSTUFF_BITS(resp, 37, 5);
> >   		csd->erase_size = (a + 1) * (b + 1);
> >   		csd->erase_size <<= csd->write_blkbits - 9;
> > +		csd->wp_grp_size = UNSTUFF_BITS(resp, 32, 5);
> >   	}
> >   
> >   	return 0;
> > @@ -791,6 +803,7 @@ MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card-
> > >raw_csd[0], card->raw_csd[1],
> >   MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card-
> > >cid.year);
> >   MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
> >   MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase <<
> > 9);
> > +MMC_DEV_ATTR(wp_grp_size, "%u\n", card->wp_grp_size << 9);
> >   MMC_DEV_ATTR(ffu_capable, "%d\n", card->ext_csd.ffu_capable);
> >   MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
> >   MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
> > @@ -851,6 +864,7 @@ static struct attribute *mmc_std_attrs[] = {
> >   	&dev_attr_date.attr,
> >   	&dev_attr_erase_size.attr,
> >   	&dev_attr_preferred_erase_size.attr,
> > +	&dev_attr_wp_grp_size.attr,
> >   	&dev_attr_fwrev.attr,
> >   	&dev_attr_ffu_capable.attr,
> >   	&dev_attr_hwrev.attr,
> > @@ -1759,7 +1773,7 @@ static int mmc_init_card(struct mmc_host
> > *host, u32 ocr,
> >   			mmc_set_erase_size(card);
> >   		}
> >   	}
> > -
> > +	mmc_set_wp_grp_size(card);
> >   	/*
> >   	 * Ensure eMMC user default partition is enabled
> >   	 */
> > diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
> > index daa2f40d9ce6..62873ecc52f1 100644
> > --- a/include/linux/mmc/card.h
> > +++ b/include/linux/mmc/card.h
> > @@ -32,6 +32,7 @@ struct mmc_csd {
> >   	unsigned int		r2w_factor;
> >   	unsigned int		max_dtr;
> >   	unsigned int		erase_size;		/* In
> > sectors */
> > +	unsigned int		wp_grp_size;
> >   	unsigned int		read_blkbits;
> >   	unsigned int		write_blkbits;
> >   	unsigned int		capacity;
> > @@ -304,6 +305,7 @@ struct mmc_card {
> >   	unsigned int		eg_boundary;	/* don't cross
> > erase-group boundaries */
> >   	unsigned int		erase_arg;	/* erase / trim /
> > discard */
> >    	u8			erased_byte;	/* value of erased bytes */
> > +	unsigned int		wp_grp_size;	/* write group size in
> > sectors */
> 
> There should be a tabulation before the comment, not a space.
  Done: replaced space with tabulation. I will run scripts/check-
patch.pl before uploading patch next time to avoid code style
violation.
> 
> Regards,
> Angelo
>