mmc: export the speed class info of SD card to sysfs

BZ: 5474

This patch exports the SD status register's speed class info to sysfs

Change-Id: I847ced0d3a632c706c0f7ab93b0dac2f7d6c8d00
Signed-off-by: Hao Ying <hao.ying@intel.com>
Reviewed-on: http://android.intel.com:8080/23129
Reviewed-by: Gross, Mark <mark.gross@intel.com>
Tested-by: Gross, Mark <mark.gross@intel.com>

diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 35fcc0e..a6a43bf 100644 (file)
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -213,7 +213,7 @@ static int mmc_decode_scr(struct mmc_card *card)
  */
 static int mmc_read_ssr(struct mmc_card *card)
 {
-       unsigned int au, es, et, eo;
+       unsigned int sc, au, es, et, eo;
        int err, i;
        u32 *ssr;
 
@@ -242,6 +242,26 @@ static int mmc_read_ssr(struct mmc_card *card)
         * UNSTUFF_BITS only works with four u32s so we have to offset the
         * bitfield positions accordingly.
         */
+       sc = UNSTUFF_BITS(ssr, 440 - 384, 8);
+       switch (sc) {
+       case 0:
+               card->ssr.speed_class = 0;
+               break;
+       case 1:
+               card->ssr.speed_class = 2;
+               break;
+       case 2:
+               card->ssr.speed_class = 4;
+               break;
+       case 3:
+               card->ssr.speed_class = 6;
+               break;
+       case 4:
+               card->ssr.speed_class = 10;
+               break;
+       default:
+               card->ssr.speed_class = -1;
+       }
        au = UNSTUFF_BITS(ssr, 428 - 384, 4);
        if (au > 0 || au <= 9) {
                card->ssr.au = 1 << (au + 4);
@@ -657,7 +677,7 @@ MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
-
+MMC_DEV_ATTR(speed_class, "%u\n", card->ssr.speed_class);
 
 static struct attribute *sd_std_attrs[] = {
        &dev_attr_cid.attr,
@@ -672,6 +692,7 @@ static struct attribute *sd_std_attrs[] = {
        &dev_attr_name.attr,
        &dev_attr_oemid.attr,
        &dev_attr_serial.attr,
+       &dev_attr_speed_class.attr,
        NULL,
 };
 

diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index a45c5b8..58ffd35 100644 (file)
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -92,6 +92,7 @@ struct sd_scr {
 };
 
 struct sd_ssr {
+       unsigned short          speed_class;
        unsigned int            au;                     /* In sectors */
        unsigned int            erase_timeout;          /* In milliseconds */
        unsigned int            erase_offset;           /* In milliseconds */