Re: [PATCH 2/2] mmc: core: Export device/vendor ids from Common CIS for SDIO cards

[Ulf Hansson <ulf.hansson@linaro.org>]

On Tue, 26 May 2020 at 17:43, Pali Rohár <pali@kernel.org> wrote:
>
> Device/vendor ids from Common CIS (Card Information Structure) may be
> different as device/vendor ids from CIS on particular SDIO function.
>
> Export these "main" device/vendor ids for SDIO and SD combo cards at top
> level mmc device in sysfs so userspace can do better identification of
> connected SDIO and SD combo cards.

What would userspace do with this information, more exactly?

Isn't it just sufficient to give events per SDIO func, as we already
do in sdio_bus_uevent()?

Kind regards
Uffe

>
> Signed-off-by: Pali Rohár <pali@kernel.org>
> Reviewed-by: Marek Behún <marek.behun@nic.cz>
> ---
>  drivers/mmc/core/bus.c  |  7 +++++++
>  drivers/mmc/core/sd.c   | 26 +++++++++++++++++++++++++-
>  drivers/mmc/core/sdio.c | 20 +++++++++++++++++++-
>  3 files changed, 51 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
> index 103eea7cd..5d4b28b29 100644
> --- a/drivers/mmc/core/bus.c
> +++ b/drivers/mmc/core/bus.c
> @@ -93,6 +93,13 @@ mmc_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
>                         return retval;
>         }
>
> +       if (card->type == MMC_TYPE_SDIO || card->type == MMC_TYPE_SD_COMBO) {
> +               retval = add_uevent_var(env, "SDIO_ID=%04X:%04X",
> +                                       card->cis.vendor, card->cis.device);
> +               if (retval)
> +                       return retval;
> +       }
> +
>         if (card->type != MMC_TYPE_SDIO) {
>                 retval = add_uevent_var(env, "MMC_NAME=%s", mmc_card_name(card));
>                 if (retval)
> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> index 76c7add36..ee1a51ff6 100644
> --- a/drivers/mmc/core/sd.c
> +++ b/drivers/mmc/core/sd.c
> @@ -707,7 +707,12 @@ static ssize_t mmc_dsr_show(struct device *dev,
>
>  static DEVICE_ATTR(dsr, S_IRUGO, mmc_dsr_show, NULL);
>
> +MMC_DEV_ATTR(vendor, "0x%04x\n", card->cis.vendor);
> +MMC_DEV_ATTR(device, "0x%04x\n", card->cis.device);
> +
>  static struct attribute *sd_std_attrs[] = {
> +       &dev_attr_vendor.attr,
> +       &dev_attr_device.attr,
>         &dev_attr_cid.attr,
>         &dev_attr_csd.attr,
>         &dev_attr_scr.attr,
> @@ -726,7 +731,26 @@ static struct attribute *sd_std_attrs[] = {
>         &dev_attr_dsr.attr,
>         NULL,
>  };
> -ATTRIBUTE_GROUPS(sd_std);
> +
> +static umode_t sd_std_is_visible(struct kobject *kobj, struct attribute *attr,
> +                                int index)
> +{
> +       struct device *dev = container_of(kobj, struct device, kobj);
> +       struct mmc_card *card = mmc_dev_to_card(dev);
> +
> +       /* CIS vendor and device ids are available only for Combo cards */
> +       if ((attr == &dev_attr_vendor.attr || attr == &dev_attr_device.attr) &&
> +           card->type != MMC_TYPE_SD_COMBO)
> +               return 0;
> +
> +       return attr->mode;
> +}
> +
> +static const struct attribute_group sd_std_group = {
> +       .attrs = sd_std_attrs,
> +       .is_visible = sd_std_is_visible,
> +};
> +__ATTRIBUTE_GROUPS(sd_std);
>
>  struct device_type sd_type = {
>         .groups = sd_std_groups,
> diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
> index ebb387aa5..d708e0fbc 100644
> --- a/drivers/mmc/core/sdio.c
> +++ b/drivers/mmc/core/sdio.c
> @@ -27,6 +27,24 @@
>  #include "sdio_ops.h"
>  #include "sdio_cis.h"
>
> +MMC_DEV_ATTR(vendor, "0x%04x\n", card->cis.vendor);
> +MMC_DEV_ATTR(device, "0x%04x\n", card->cis.device);
> +MMC_DEV_ATTR(ocr, "0x%08x\n", card->ocr);
> +MMC_DEV_ATTR(rca, "0x%04x\n", card->rca);
> +
> +static struct attribute *sdio_std_attrs[] = {
> +       &dev_attr_vendor.attr,
> +       &dev_attr_device.attr,
> +       &dev_attr_ocr.attr,
> +       &dev_attr_rca.attr,
> +       NULL,
> +};
> +ATTRIBUTE_GROUPS(sdio_std);
> +
> +struct device_type sdio_type = {
> +       .groups = sdio_std_groups,
> +};
> +
>  static int sdio_read_fbr(struct sdio_func *func)
>  {
>         int ret;
> @@ -598,7 +616,7 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
>         /*
>          * Allocate card structure.
>          */
> -       card = mmc_alloc_card(host, NULL);
> +       card = mmc_alloc_card(host, &sdio_type);
>         if (IS_ERR(card)) {
>                 err = PTR_ERR(card);
>                 goto err;
> --
> 2.20.1
>