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>

diff --git a/drivers/mfd/twl4030-core.c b/drivers/mfd/twl4030-core.c
index e424cf6..e832e97 100644 (file)
--- 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);