mfd: Fix twl4030 boot with twl4030 usb transceiver enabled

The usb regulator supplies (usb1v5, usb1v8 & usb3v1) must be available
before adding the twl4030_usb child, else twl4030_usb_ldo_init() will
always fail thus causing boot lock-up.

This patch fixes boot on OMAP systems using the twl4030 usb transceiver.
CONFIG_TWL4030_USB=y

Signed-off-by: Roger Quadros <ext-roger.quadros@nokia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 46 insertions, 43 deletions

diff --git a/drivers/mfd/twl4030-core.c b/drivers/mfd/twl4030-core.c
index e424cf6d8e9e..e832e975da60 100644
--- a/drivers/mfd/twl4030-core.c
+++ b/drivers/mfd/twl4030-core.c
@@ -480,7 +480,6 @@ static int
 add_children(struct twl4030_platform_data *pdata, unsigned long features)
 {
         struct device   *child;
-        struct device   *usb_transceiver = NULL;
 
         if (twl_has_bci() && pdata->bci && !(features & TPS_SUBSET)) {
                 child = add_child(3, "twl4030_bci",
@@ -532,16 +531,61 @@ add_children(struct twl4030_platform_data *pdata, unsigned long features)
         }
 
         if (twl_has_usb() && pdata->usb) {
+
+                static struct regulator_consumer_supply usb1v5 = {
+                        .supply =       "usb1v5",
+                };
+                static struct regulator_consumer_supply usb1v8 = {
+                        .supply =       "usb1v8",
+                };
+                static struct regulator_consumer_supply usb3v1 = {
+                        .supply =       "usb3v1",
+                };
+
+        /* First add the regulators so that they can be used by transceiver */
+                if (twl_has_regulator()) {
+                        /* this is a template that gets copied */
+                        struct regulator_init_data usb_fixed = {
+                                .constraints.valid_modes_mask =
+                                        REGULATOR_MODE_NORMAL
+                                        | REGULATOR_MODE_STANDBY,
+                                .constraints.valid_ops_mask =
+                                        REGULATOR_CHANGE_MODE
+                                        | REGULATOR_CHANGE_STATUS,
+                        };
+
+                        child = add_regulator_linked(TWL4030_REG_VUSB1V5,
+                                                      &usb_fixed, &usb1v5, 1);
+                        if (IS_ERR(child))
+                                return PTR_ERR(child);
+
+                        child = add_regulator_linked(TWL4030_REG_VUSB1V8,
+                                                      &usb_fixed, &usb1v8, 1);
+                        if (IS_ERR(child))
+                                return PTR_ERR(child);
+
+                        child = add_regulator_linked(TWL4030_REG_VUSB3V1,
+                                                      &usb_fixed, &usb3v1, 1);
+                        if (IS_ERR(child))
+                                return PTR_ERR(child);
+
+                }
+
                 child = add_child(0, "twl4030_usb",
                                 pdata->usb, sizeof(*pdata->usb),
                                 true,
                                 /* irq0 = USB_PRES, irq1 = USB */
                                 pdata->irq_base + 8 + 2, pdata->irq_base + 4);
+
                 if (IS_ERR(child))
                         return PTR_ERR(child);
 
                 /* we need to connect regulators to this transceiver */
-                usb_transceiver = child;
+                if (twl_has_regulator() && child) {
+                        usb1v5.dev = child;
+                        usb1v8.dev = child;
+                        usb3v1.dev = child;
+                }
         }
 
         if (twl_has_watchdog()) {
@@ -580,47 +624,6 @@ add_children(struct twl4030_platform_data *pdata, unsigned long features)
                         return PTR_ERR(child);
         }
 
-        if (twl_has_regulator() && usb_transceiver) {
-                static struct regulator_consumer_supply usb1v5 = {
-                        .supply =       "usb1v5",
-                };
-                static struct regulator_consumer_supply usb1v8 = {
-                        .supply =       "usb1v8",
-                };
-                static struct regulator_consumer_supply usb3v1 = {
-                        .supply =       "usb3v1",
-                };
-
-                /* this is a template that gets copied */
-                struct regulator_init_data usb_fixed = {
-                        .constraints.valid_modes_mask =
-                                  REGULATOR_MODE_NORMAL
-                                | REGULATOR_MODE_STANDBY,
-                        .constraints.valid_ops_mask =
-                                  REGULATOR_CHANGE_MODE
-                                | REGULATOR_CHANGE_STATUS,
-                };
-
-                usb1v5.dev = usb_transceiver;
-                usb1v8.dev = usb_transceiver;
-                usb3v1.dev = usb_transceiver;
-
-                child = add_regulator_linked(TWL4030_REG_VUSB1V5, &usb_fixed,
-                                &usb1v5, 1);
-                if (IS_ERR(child))
-                        return PTR_ERR(child);
-
-                child = add_regulator_linked(TWL4030_REG_VUSB1V8, &usb_fixed,
-                                &usb1v8, 1);
-                if (IS_ERR(child))
-                        return PTR_ERR(child);
-
-                child = add_regulator_linked(TWL4030_REG_VUSB3V1, &usb_fixed,
-                                &usb3v1, 1);
-                if (IS_ERR(child))
-                        return PTR_ERR(child);
-        }
-
         /* maybe add LDOs that are omitted on cost-reduced parts */
         if (twl_has_regulator() && !(features & TPS_SUBSET)) {
                 child = add_regulator(TWL4030_REG_VPLL2, pdata->vpll2);