mmc: core: Fix partition switch time for eMMC

Avoid the following warning by always defining partition switch time:

 [    3.209874] mmc1: unspecified timeout for CMD6 - use generic
 [    3.222780] ------------[ cut here ]------------
 [    3.233363] WARNING: CPU: 1 PID: 111 at drivers/mmc/core/mmc_ops.c:575 __mmc_switch+0x200/0x204

Reported-by: Paul Fertser <fercerpav@gmail.com>
Fixes: 1c447116d017 ("mmc: mmc: Fix partition switch timeout for some eMMCs")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/168bbfd6-0c5b-5ace-ab41-402e7937c46e@intel.com
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 0d80b72..8741271 100644 (file)
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -423,10 +423,6 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
 
                /* EXT_CSD value is in units of 10ms, but we store in ms */
                card->ext_csd.part_time = 10 * ext_csd[EXT_CSD_PART_SWITCH_TIME];
-               /* Some eMMC set the value too low so set a minimum */
-               if (card->ext_csd.part_time &&
-                   card->ext_csd.part_time < MMC_MIN_PART_SWITCH_TIME)
-                       card->ext_csd.part_time = MMC_MIN_PART_SWITCH_TIME;
 
                /* Sleep / awake timeout in 100ns units */
                if (sa_shift > 0 && sa_shift <= 0x17)
@@ -616,6 +612,17 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
                card->ext_csd.data_sector_size = 512;
        }
 
+       /*
+        * GENERIC_CMD6_TIME is to be used "unless a specific timeout is defined
+        * when accessing a specific field", so use it here if there is no
+        * PARTITION_SWITCH_TIME.
+        */
+       if (!card->ext_csd.part_time)
+               card->ext_csd.part_time = card->ext_csd.generic_cmd6_time;
+       /* Some eMMC set the value too low so set a minimum */
+       if (card->ext_csd.part_time < MMC_MIN_PART_SWITCH_TIME)
+               card->ext_csd.part_time = MMC_MIN_PART_SWITCH_TIME;
+
        /* eMMC v5 or later */
        if (card->ext_csd.rev >= 7) {
                memcpy(card->ext_csd.fwrev, &ext_csd[EXT_CSD_FIRMWARE_VERSION],