ARM: OMAP3: mmc-twl4030 fix for vmmc = 0

Resolve longstanding issue noted by Adrian Hunter:  confusion
between settting VSEL=0 (which is 1.8V on MMC1) and poweroff.

Also, leave VSEL alone if we're just powering the regulator off.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>

1 files changed, 10 insertions, 8 deletions

diff --git a/arch/arm/mach-omap2/mmc-twl4030.c b/arch/arm/mach-omap2/mmc-twl4030.c
index d9fad8dda152..d43421400e9d 100644
--- a/arch/arm/mach-omap2/mmc-twl4030.c
+++ b/arch/arm/mach-omap2/mmc-twl4030.c
@@ -178,7 +178,10 @@ static int twl_mmc_resume(struct device *dev, int slot)
 static int twl_mmc_set_voltage(struct twl_mmc_controller *c, int vdd)
 {
         int ret;
-        u8 vmmc, dev_grp_val;
+        u8 vmmc = 0, dev_grp_val;
+
+        if (!vdd)
+                goto doit;
 
         if (c->twl_vmmc_dev_grp == VMMC1_DEV_GRP) {
                 /* VMMC1:  max 220 mA.  And for 8-bit mode,
@@ -203,8 +206,7 @@ static int twl_mmc_set_voltage(struct twl_mmc_controller *c, int vdd)
                         /* error if VSIM needed */
                         break;
                 default:
-                        vmmc = 0;
-                        break;
+                        return -EINVAL;
                 }
         } else if (c->twl_vmmc_dev_grp == VMMC2_DEV_GRP) {
                 /* VMMC2:  max 100 mA */
@@ -230,21 +232,21 @@ static int twl_mmc_set_voltage(struct twl_mmc_controller *c, int vdd)
                         vmmc = VMMC2_315V;
                         break;
                 default:
-                        vmmc = 0;
-                        break;
+                        return -EINVAL;
                 }
         } else {
-                return 0;
+                return -EINVAL;
         }
 
-        if (vmmc)
+doit:
+        if (vdd)
                 dev_grp_val = VMMC_DEV_GRP_P1;  /* Power up */
         else
                 dev_grp_val = LDO_CLR;          /* Power down */
 
         ret = twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER,
                                         dev_grp_val, c->twl_vmmc_dev_grp);
-        if (ret)
+        if (ret || !vdd)
                 return ret;
 
         ret = twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER,