RE: [PATCH 2/2] mmc: core: add reliable write setting to sysfs and update on read

[Avri Altman]

> The mmc reliable write setting (from ext_csd) was not available on the sysfs.
> Thus, added rel_param and rel_write_set to sysfs and added the update of
> rel_write_set on sysfs read.
Here also - why adding ABI when its already available via mmc-utils?

Thanks,
Avri

> 
> Signed-off-by: Marc Mattmueller <marc.mattmueller@xxxxxxxxxxxxx>
> ---
>  drivers/mmc/core/mmc.c   | 29 +++++++++++++++++++++++++++++
>  include/linux/mmc/card.h |  1 +
>  include/linux/mmc/mmc.h  |  1 +
>  3 files changed, 31 insertions(+)
> 
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index
> d9537c894e33..a64d1ecb0de9 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -364,6 +364,10 @@ static int
> mmc_update_ext_csd_runtime_params(struct mmc_card *card, u8
> *ext_csd)  {
>         int err = 0;
> 
> +       /* eMMC v4.41 or later */
> +       if (card->ext_csd.rev >= 5)
> +               card->ext_csd.rel_wr_set = ext_csd[EXT_CSD_WR_REL_SET];
> +
>         /* eMMC v5 or later */
>         if (card->ext_csd.rev >= 7) {
>                 card->ext_csd.pre_eol_info = ext_csd[EXT_CSD_PRE_EOL_INFO];
> @@ -587,6 +591,7 @@ static int mmc_decode_ext_csd(struct mmc_card
> *card, u8 *ext_csd)
>                 }
> 
>                 card->ext_csd.rel_param = ext_csd[EXT_CSD_WR_REL_PARAM];
> +               card->ext_csd.rel_wr_set = ext_csd[EXT_CSD_WR_REL_SET];
>                 card->ext_csd.rst_n_function =
> ext_csd[EXT_CSD_RST_N_FUNCTION];
> 
>                 /*
> @@ -820,6 +825,7 @@ MMC_DEV_ATTR(name, "%s\n", card-
> >cid.prod_name);  MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
> MMC_DEV_ATTR(prv, "0x%x\n", card->cid.prv);  MMC_DEV_ATTR(rev,
> "0x%x\n", card->ext_csd.rev);
> +MMC_DEV_ATTR(rel_param, "0x%02x\n", card->ext_csd.rel_param);
>  MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
> MMC_DEV_ATTR(enhanced_area_offset, "%llu\n",
>                 card->ext_csd.enhanced_area_offset);
> @@ -886,6 +892,27 @@ static ssize_t pre_eol_info_show(struct device
> *dev,
> 
>  static DEVICE_ATTR_RO(pre_eol_info);
> 
> +static ssize_t rel_write_set_show(struct device *dev,
> +                                 struct device_attribute *attr,
> +                                 char *buf) {
> +       int err = 0;
> +       struct mmc_card *card = mmc_dev_to_card(dev);
> +
> +       /* before eMMC v4.41 */
> +       if (card->ext_csd.rev < 5)
> +               return sprintf(buf, "%s\n", "-");
> +
> +       /* eMMC v4.41 or later */
> +       err = mmc_update_csd(card);
> +       if (err)
> +               return (ssize_t)err;
> +
> +       return sprintf(buf, "0x%02x\n", card->ext_csd.rel_wr_set); }
> +
> +static DEVICE_ATTR_RO(rel_write_set);
> +
>  static ssize_t mmc_fwrev_show(struct device *dev,
>                               struct device_attribute *attr,
>                               char *buf) @@ -931,6 +958,8 @@ static struct attribute
> *mmc_std_attrs[] = {
>         &dev_attr_oemid.attr,
>         &dev_attr_prv.attr,
>         &dev_attr_rev.attr,
> +       &dev_attr_rel_param.attr,
> +       &dev_attr_rel_write_set.attr,
>         &dev_attr_pre_eol_info.attr,
>         &dev_attr_life_time.attr,
>         &dev_attr_serial.attr,
> diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index
> 37f975875102..21c47893fcb4 100644
> --- a/include/linux/mmc/card.h
> +++ b/include/linux/mmc/card.h
> @@ -48,6 +48,7 @@ struct mmc_ext_csd {
>         u8                      sec_feature_support;
>         u8                      rel_sectors;
>         u8                      rel_param;
> +       u8                      rel_wr_set;
>         bool                    enhanced_rpmb_supported;
>         u8                      part_config;
>         u8                      cache_ctrl;
> diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h index
> d9a65c6a8816..42afd442a70a 100644
> --- a/include/linux/mmc/mmc.h
> +++ b/include/linux/mmc/mmc.h
> @@ -266,6 +266,7 @@ static inline bool mmc_ready_for_data(u32 status)
>  #define EXT_CSD_BKOPS_START            164     /* W */
>  #define EXT_CSD_SANITIZE_START         165     /* W */
>  #define EXT_CSD_WR_REL_PARAM           166     /* RO */
> +#define EXT_CSD_WR_REL_SET             167     /* R/W */
>  #define EXT_CSD_RPMB_MULT              168     /* RO */
>  #define EXT_CSD_FW_CONFIG              169     /* R/W */
>  #define EXT_CSD_BOOT_WP                        173     /* R/W */
> --
> 2.20.1