mmc: sdhci: only set 200mA support for 1.8v if 200mA is available

max_current_caps can return 0 if not available from the sd controller.
If no regulator is present or the regulator specifies a current
less then 200ma, we no longer still set the 200mA caps bit anyway.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Reviewed-by: Aaron Lu <aaron_lu@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 12 insertions, 11 deletions

diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index b2b43f624b9..b0b9e372f5d 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -553,13 +553,13 @@ static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status)
 
 static int sd_set_current_limit(struct mmc_card *card, u8 *status)
 {
-        int current_limit = 0;
+        int current_limit = SD_SET_CURRENT_NO_CHANGE;
         int err;
 
         /*
          * Current limit switch is only defined for SDR50, SDR104, and DDR50
-         * bus speed modes. For other bus speed modes, we set the default
-         * current limit of 200mA.
+         * bus speed modes. For other bus speed modes, we do not change the
+         * current limit.
          */
         if ((card->sd_bus_speed == UHS_SDR50_BUS_SPEED) ||
             (card->sd_bus_speed == UHS_SDR104_BUS_SPEED) ||
@@ -595,17 +595,18 @@ static int sd_set_current_limit(struct mmc_card *card, u8 *status)
                         if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_200)
                                 current_limit = SD_SET_CURRENT_LIMIT_200;
                 }
-        } else
-                current_limit = SD_SET_CURRENT_LIMIT_200;
+        }
 
-        err = mmc_sd_switch(card, 1, 3, current_limit, status);
-        if (err)
-                return err;
+        if (current_limit != SD_SET_CURRENT_NO_CHANGE) {
+                err = mmc_sd_switch(card, 1, 3, current_limit, status);
+                if (err)
+                        return err;
 
-        if (((status[15] >> 4) & 0x0F) != current_limit)
-                pr_warning("%s: Problem setting current limit!\n",
-                        mmc_hostname(card->host));
+                if (((status[15] >> 4) & 0x0F) != current_limit)
+                        pr_warning("%s: Problem setting current limit!\n",
+                                mmc_hostname(card->host));
 
+        }
         return 0;
 }