regulator: ab8500: Update info->update_val only when successfully update register

Don't update info->update_val if write to the register fails.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 19 insertions, 8 deletions

diff --git a/drivers/regulator/ab8500.c b/drivers/regulator/ab8500.c
index bf34c4cd6631..c7b433a2a3a9 100644
--- a/drivers/regulator/ab8500.c
+++ b/drivers/regulator/ab8500.c
@@ -184,8 +184,8 @@ static unsigned int ab8500_regulator_get_optimum_mode(
 static int ab8500_regulator_set_mode(struct regulator_dev *rdev,
                                      unsigned int mode)
 {
-        int ret = 0;
-
+        int ret;
+        u8 update_val;
         struct ab8500_regulator_info *info = rdev_get_drvdata(rdev);
 
         if (info == NULL) {
@@ -195,31 +195,42 @@ static int ab8500_regulator_set_mode(struct regulator_dev *rdev,
 
         switch (mode) {
         case REGULATOR_MODE_NORMAL:
-                info->update_val = info->update_val_normal;
+                update_val = info->update_val_normal;
                 break;
         case REGULATOR_MODE_IDLE:
-                info->update_val = info->update_val_idle;
+                update_val = info->update_val_idle;
                 break;
         default:
                 return -EINVAL;
         }
 
+        /* ab8500 regulators share mode and enable in the same register bits.
+           off = 0b00
+           low power mode= 0b11
+           full powermode = 0b01
+           (HW control mode = 0b10)
+           Thus we don't write to the register when regulator is disabled.
+        */
         if (info->is_enabled) {
                 ret = abx500_mask_and_set_register_interruptible(info->dev,
                         info->update_bank, info->update_reg,
-                        info->update_mask, info->update_val);
-                if (ret < 0)
+                        info->update_mask, update_val);
+                if (ret < 0) {
                         dev_err(rdev_get_dev(rdev),
                                 "couldn't set regulator mode\n");
+                        return ret;
+                }
 
                 dev_vdbg(rdev_get_dev(rdev),
                         "%s-set_mode (bank, reg, mask, value): "
                         "0x%x, 0x%x, 0x%x, 0x%x\n",
                         info->desc.name, info->update_bank, info->update_reg,
-                        info->update_mask, info->update_val);
+                        info->update_mask, update_val);
         }
 
-        return ret;
+        info->update_val = update_val;
+
+        return 0;
 }
 
 static unsigned int ab8500_regulator_get_mode(struct regulator_dev *rdev)