mmc: dw_mmc: Check return value of regulator_enable

regulator_enable() is declared with __must_check attribute.
Hence check the return value to ensure that the regulator is enabled.

Fixes the following warning:

drivers/mmc/host/dw_mmc.c:2461:19: warning:
ignoring return value of ‘regulator_enable’, declared with attribute
warn_unused_result [-Wunused-result]
drivers/mmc/host/dw_mmc.c: In function ‘dw_mci_init_slot’:
drivers/mmc/host/dw_mmc.c:1994:19: warning:
ignoring return value of ‘regulator_enable’, declared with attribute
warn_unused_result [-Wunused-result]

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 16 insertions, 4 deletions

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index c6caedc2e847..a63766a0bfcd 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1997,8 +1997,14 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
         if (IS_ERR(host->vmmc)) {
                 pr_info("%s: no vmmc regulator found\n", mmc_hostname(mmc));
                 host->vmmc = NULL;
-        } else
-                regulator_enable(host->vmmc);
+        } else {
+                ret = regulator_enable(host->vmmc);
+                if (ret) {
+                        dev_err(host->dev,
+                                "failed to enable regulator: %d\n", ret);
+                        goto err_setup_bus;
+                }
+        }
 
         if (dw_mci_get_cd(mmc))
                 set_bit(DW_MMC_CARD_PRESENT, &slot->flags);
@@ -2464,8 +2470,14 @@ int dw_mci_resume(struct dw_mci *host)
 {
         int i, ret;
 
-        if (host->vmmc)
-                regulator_enable(host->vmmc);
+        if (host->vmmc) {
+                ret = regulator_enable(host->vmmc);
+                if (ret) {
+                        dev_err(host->dev,
+                                "failed to enable regulator: %d\n", ret);
+                        return ret;
+                }
+        }
 
         if (!mci_wait_reset(host->dev, host)) {
                 ret = -ENODEV;