Re: [PATCH v2] twl4030: Fix boot with twl4030 usb transceiver enabled

From: Roger Quadros
Date: Fri Oct 09 2009 - 11:58:12 EST


Hi,

I just observed that this patch does not work as intended with 2.6.31.3

It seems that twl4030_usb_probe() and hence twl4030_usb_ldo_init() is called before the required regulators have been 'linked' to the device in twl4030-core.c, thus causing regulator_get(twl->dev, "usb3v1"); to fail, and the boot lockup

Isn't there a better way to avoid such a situation?

cheers,
-roger

ext Roger Quadros wrote:
Hi Samuel,

What is the status of this patch?
Without this patch we are unable to boot on systems using musb usb controller.

cheers,
-roger.

On Thu, Oct 1, 2009 at 11:25 AM, Roger Quadros
<ext-roger.quadros@xxxxxxxxx> wrote:
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@xxxxxxxxx>
---
drivers/mfd/twl4030-core.c | 89 ++++++++++++++++++++++---------------------
1 files changed, 46 insertions(+), 43 deletions(-)

diff --git a/drivers/mfd/twl4030-core.c b/drivers/mfd/twl4030-core.c
index e424cf6..e832e97 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);
--
1.6.0.4

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