[PATCH v2 2/2] mmc: core: Export device/vendor ids from Common CIS for SDIO cards

["Pali Rohár" <pali@kernel.org>]

Device/vendor ids from Common CIS (Card Information Structure) may be
different as device/vendor ids from CIS on particular SDIO function.

Kernel currently exports only device/vendor ids from SDIO functions and not
"main" device/vendor ids from Common CIS.

This patch exports "main" device/vendor ids for SDIO and SD combo cards at
top level mmc device in sysfs hierarchy.

Userspace can use e.g. udev rules to correctly match whole SDIO card based
on Common CIS device/vendor id and not only one particular SDIO function.
Having this information in userspace also helps developers to debug whole
SDIO card as e.g. kernel mmc quirks use device/vendor ids from Common CIS
and not from particular SDIO function. Also it allows to write userspace
applications which list all connected SDIO cards based on CIS ids.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>

---
Changes in V2:
* Make sd_std_group static
* Put more information into commit message
---
 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 b1cb447da..70207f11a 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;
+	}
+
 	/*
 	 * SDIO (non-combo) cards are not handled by mmc_block driver and do not
 	 * have accessible CID register which used by mmc_card_name() function.
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..2d86a9db5 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);
+
+static 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