mmc: block: Update ext_csd.cache_ctrl if it was written

BugLink: https://bugs.launchpad.net/bugs/1928825
commit aea0440ad023ab0662299326f941214b0d7480bd upstream.

The cache function can be turned ON and OFF by writing to the CACHE_CTRL
byte (EXT_CSD byte [33]).  However,  card->ext_csd.cache_ctrl is only
set on init if cache size > 0.

Fix that by explicitly setting ext_csd.cache_ctrl on ext-csd write.

Signed-off-by: Avri Altman <avri.altman@wdc.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210420134641.57343-3-avri.altman@wdc.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 63e838ec8af84fb767ab7aadf2f9772f57043784..e5e6ea7bffc44f472df68d04c025a85235dc5c1c 100644 (file)
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -621,6 +621,18 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md,
                main_md->part_curr = value & EXT_CSD_PART_CONFIG_ACC_MASK;
        }
 
+       /*
+        * Make sure to update CACHE_CTRL in case it was changed. The cache
+        * will get turned back on if the card is re-initialized, e.g.
+        * suspend/resume or hw reset in recovery.
+        */
+       if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_CACHE_CTRL) &&
+           (cmd.opcode == MMC_SWITCH)) {
+               u8 value = MMC_EXTRACT_VALUE_FROM_ARG(cmd.arg) & 1;
+
+               card->ext_csd.cache_ctrl = value;
+       }
+
        /*
         * According to the SD specs, some commands require a delay after
         * issuing the command.