by Kishon Vijay Abraham I

[permalink] [raw]

Subject: [PATCH v5] usb: dwc3: use extcon fwrk to receive connect/disconnect

Modified dwc3-omap to receive connect and disconnect notification using
extcon framework. Also did the necessary cleanups required after
adapting to extcon framework.

Signed-off-by: Kishon Vijay Abraham I <[email protected]>
Acked-by: Felipe Balbi <[email protected]>
Acked-by: Chanwoo Choi <[email protected]>
---
This patch should be applied after all of the extcon patchset will be applied
because this patch has dependency of extcon patch related to DT.
http://goo.gl/Tu3qW

Changes from v4:
* checked the return values of extcon_register_interest and print an error
message. Note that I dint do return since there might be cases where
one of USB (device mode) or USB-HOST (host mode) might succeed.
* Added depends on of EXTCON in usb_dwc3. Only some platforms might
be using EXTCON, but inorder to avoid compilation errors, added
depends on
Changes from v3:
* did #include of of_extcon.h after Chanwoo resent the patch separating
extcon-class.c from of_extcon.c
Changes from v2:
* updated the Documentation with dwc3 dt binding information.
* used of_extcon_get_extcon_dev to get extcon device from device tree data.
Changes from v1:
* regulator enable/disable is now done here instead of palmas-usb as some users
of palmas-usb wont need regulator.

Documentation/devicetree/bindings/usb/omap-usb.txt | 5 +
drivers/usb/dwc3/Kconfig | 1 +
drivers/usb/dwc3/dwc3-omap.c | 125 +++++++++++++++++---
include/linux/usb/dwc3-omap.h | 30 -----
4 files changed, 112 insertions(+), 49 deletions(-)
delete mode 100644 include/linux/usb/dwc3-omap.h

diff --git a/Documentation/devicetree/bindings/usb/omap-usb.txt b/Documentation/devicetree/bindings/usb/omap-usb.txt
index d4769f3..f1c15f3 100644
--- a/Documentation/devicetree/bindings/usb/omap-usb.txt
+++ b/Documentation/devicetree/bindings/usb/omap-usb.txt
@@ -53,6 +53,11 @@ OMAP DWC3 GLUE
It should be set to "1" for HW mode and "2" for SW mode.
- ranges: the child address space are mapped 1:1 onto the parent address space

+Optional Properties:
+ - extcon : phandle for the extcon device omap dwc3 uses to detect
+ connect/disconnect events.
+ - vbus-supply : phandle to the regulator device tree node if needed.
+
Sub-nodes:
The dwc3 core should be added as subnode to omap dwc3 glue.
- dwc3 :
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index 757aa18..08a9fab 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -1,6 +1,7 @@
config USB_DWC3
tristate "DesignWare USB3 DRD Core Support"
depends on (USB || USB_GADGET) && GENERIC_HARDIRQS
+ depends on EXTCON
select USB_XHCI_PLATFORM if USB_SUPPORT && USB_XHCI_HCD
help
Say Y or M here if your system has a Dual Role SuperSpeed
diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
index f8f76e6..80b5780 100644
--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -43,13 +43,15 @@
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/platform_data/dwc3-omap.h>
-#include <linux/usb/dwc3-omap.h>
#include <linux/pm_runtime.h>
#include <linux/dma-mapping.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_platform.h>
+#include <linux/extcon.h>
+#include <linux/extcon/of_extcon.h>
+#include <linux/regulator/consumer.h>

#include <linux/usb/otg.h>

@@ -124,9 +126,21 @@ struct dwc3_omap {
u32 utmi_otg_status;

u32 dma_status:1;
+
+ struct extcon_specific_cable_nb extcon_vbus_dev;
+ struct extcon_specific_cable_nb extcon_id_dev;
+ struct notifier_block vbus_nb;
+ struct notifier_block id_nb;
+
+ struct regulator *vbus_reg;
};

-static struct dwc3_omap *_omap;
+enum omap_dwc3_vbus_id_status {
+ OMAP_DWC3_ID_FLOAT,
+ OMAP_DWC3_ID_GROUND,
+ OMAP_DWC3_VBUS_OFF,
+ OMAP_DWC3_VBUS_VALID,
+};

static inline u32 dwc3_omap_readl(void __iomem *base, u32 offset)
{
@@ -138,18 +152,23 @@ static inline void dwc3_omap_writel(void __iomem *base, u32 offset, u32 value)
writel(value, base + offset);
}

-int dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
+static void dwc3_omap_set_mailbox(struct dwc3_omap *omap,
+ enum omap_dwc3_vbus_id_status status)
{
- u32 val;
- struct dwc3_omap *omap = _omap;
-
- if (!omap)
- return -EPROBE_DEFER;
+ int ret;
+ u32 val;

switch (status) {
case OMAP_DWC3_ID_GROUND:
dev_dbg(omap->dev, "ID GND\n");

+ if (omap->vbus_reg) {
+ ret = regulator_enable(omap->vbus_reg);
+ if (ret) {
+ dev_dbg(omap->dev, "regulator enable failed\n");
+ return;
+ }
+ }
val = dwc3_omap_readl(omap->base, USBOTGSS_UTMI_OTG_STATUS);
val &= ~(USBOTGSS_UTMI_OTG_STATUS_IDDIG
| USBOTGSS_UTMI_OTG_STATUS_VBUSVALID
@@ -172,6 +191,9 @@ int dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
break;

case OMAP_DWC3_ID_FLOAT:
+ if (omap->vbus_reg)
+ regulator_disable(omap->vbus_reg);
+
case OMAP_DWC3_VBUS_OFF:
dev_dbg(omap->dev, "VBUS Disconnect\n");

@@ -185,12 +207,9 @@ int dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
break;

default:
- dev_dbg(omap->dev, "ID float\n");
+ dev_dbg(omap->dev, "invalid state\n");
}
-
- return 0;
}
-EXPORT_SYMBOL_GPL(dwc3_omap_mailbox);

static irqreturn_t dwc3_omap_interrupt(int irq, void *_omap)
{
@@ -282,6 +301,32 @@ static void dwc3_omap_disable_irqs(struct dwc3_omap *omap)

static u64 dwc3_omap_dma_mask = DMA_BIT_MASK(32);

+static int dwc3_omap_id_notifier(struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ struct dwc3_omap *omap = container_of(nb, struct dwc3_omap, id_nb);
+
+ if (event)
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_GROUND);
+ else
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_FLOAT);
+
+ return NOTIFY_DONE;
+}
+
+static int dwc3_omap_vbus_notifier(struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ struct dwc3_omap *omap = container_of(nb, struct dwc3_omap, vbus_nb);
+
+ if (event)
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_VALID);
+ else
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_OFF);
+
+ return NOTIFY_DONE;
+}
+
static int dwc3_omap_probe(struct platform_device *pdev)
{
struct device_node *node = pdev->dev.of_node;
@@ -289,6 +334,8 @@ static int dwc3_omap_probe(struct platform_device *pdev)
struct dwc3_omap *omap;
struct resource *res;
struct device *dev = &pdev->dev;
+ struct extcon_dev *edev;
+ struct regulator *vbus_reg = NULL;

int ret = -ENOMEM;
int irq;
@@ -330,19 +377,22 @@ static int dwc3_omap_probe(struct platform_device *pdev)
return -ENOMEM;
}

+ if (of_property_read_bool(node, "vbus-supply")) {
+ vbus_reg = devm_regulator_get(dev, "vbus");
+ if (IS_ERR(vbus_reg)) {
+ dev_err(dev, "vbus init failed\n");
+ return PTR_ERR(vbus_reg);
+ }
+ }
+
spin_lock_init(&omap->lock);

omap->dev = dev;
omap->irq = irq;
omap->base = base;
+ omap->vbus_reg = vbus_reg;
dev->dma_mask = &dwc3_omap_dma_mask;

- /*
- * REVISIT if we ever have two instances of the wrapper, we will be
- * in big trouble
- */
- _omap = omap;
-
pm_runtime_enable(dev);
ret = pm_runtime_get_sync(dev);
if (ret < 0) {
@@ -381,14 +431,47 @@ static int dwc3_omap_probe(struct platform_device *pdev)

dwc3_omap_enable_irqs(omap);

+ if (of_property_read_bool(node, "extcon")) {
+ edev = of_extcon_get_extcon_dev(dev, 0);
+ if (IS_ERR(edev)) {
+ dev_vdbg(dev, "couldn't get extcon device\n");
+ ret = PTR_ERR(edev);
+ goto err2;
+ }
+
+ omap->vbus_nb.notifier_call = dwc3_omap_vbus_notifier;
+ ret = extcon_register_interest(&omap->extcon_vbus_dev,
+ edev->name, "USB", &omap->vbus_nb);
+ if (ret < 0)
+ dev_vdbg(dev,
+ "extcon register interest of *USB* failed\n");
+ omap->id_nb.notifier_call = dwc3_omap_id_notifier;
+ ret = extcon_register_interest(&omap->extcon_id_dev, edev->name,
+ "USB-HOST", &omap->id_nb);
+ if (ret < 0)
+ dev_vdbg(dev,
+ "extcon register interest of *USB-HOST* failed\n");
+
+ if (extcon_get_cable_state(edev, "USB") == true)
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_VALID);
+ if (extcon_get_cable_state(edev, "USB-HOST") == true)
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_GROUND);
+ }
+
ret = of_platform_populate(node, NULL, NULL, dev);
if (ret) {
dev_err(&pdev->dev, "failed to create dwc3 core\n");
- goto err2;
+ goto err3;
}

return 0;

+err3:
+ if (omap->extcon_vbus_dev.edev)
+ extcon_unregister_interest(&omap->extcon_vbus_dev);
+ if (omap->extcon_id_dev.edev)
+ extcon_unregister_interest(&omap->extcon_id_dev);
+
err2:
dwc3_omap_disable_irqs(omap);

@@ -405,6 +488,10 @@ static int dwc3_omap_remove(struct platform_device *pdev)
{
struct dwc3_omap *omap = platform_get_drvdata(pdev);

+ if (omap->extcon_vbus_dev.edev)
+ extcon_unregister_interest(&omap->extcon_vbus_dev);
+ if (omap->extcon_id_dev.edev)
+ extcon_unregister_interest(&omap->extcon_id_dev);
dwc3_omap_disable_irqs(omap);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
diff --git a/include/linux/usb/dwc3-omap.h b/include/linux/usb/dwc3-omap.h
deleted file mode 100644
index 5615f4d..0000000
--
1.7.10.4

2013-06-24 11:12:51

by Chanwoo Choi

[permalink] [raw]

Subject: Re: [PATCH v5] usb: dwc3: use extcon fwrk to receive connect/disconnect

On 06/21/2013 08:58 PM, Kishon Vijay Abraham I wrote:
> Modified dwc3-omap to receive connect and disconnect notification using
> extcon framework. Also did the necessary cleanups required after
> adapting to extcon framework.
>
> Signed-off-by: Kishon Vijay Abraham I <[email protected]>
> Acked-by: Felipe Balbi <[email protected]>
> Acked-by: Chanwoo Choi <[email protected]>
> ---
> This patch should be applied after all of the extcon patchset will be applied
> because this patch has dependency of extcon patch related to DT.
> http://goo.gl/Tu3qW
>
> Changes from v4:
> * checked the return values of extcon_register_interest and print an error
> message. Note that I dint do return since there might be cases where
> one of USB (device mode) or USB-HOST (host mode) might succeed.
> * Added depends on of EXTCON in usb_dwc3. Only some platforms might
> be using EXTCON, but inorder to avoid compilation errors, added
> depends on
> Changes from v3:
> * did #include of of_extcon.h after Chanwoo resent the patch separating
> extcon-class.c from of_extcon.c
> Changes from v2:
> * updated the Documentation with dwc3 dt binding information.
> * used of_extcon_get_extcon_dev to get extcon device from device tree data.
> Changes from v1:
> * regulator enable/disable is now done here instead of palmas-usb as some users
> of palmas-usb wont need regulator.
>
> Documentation/devicetree/bindings/usb/omap-usb.txt | 5 +
> drivers/usb/dwc3/Kconfig | 1 +
> drivers/usb/dwc3/dwc3-omap.c | 125 +++++++++++++++++---
> include/linux/usb/dwc3-omap.h | 30 -----
> 4 files changed, 112 insertions(+), 49 deletions(-)
> delete mode 100644 include/linux/usb/dwc3-omap.h
>
> diff --git a/Documentation/devicetree/bindings/usb/omap-usb.txt b/Documentation/devicetree/bindings/usb/omap-usb.txt
> index d4769f3..f1c15f3 100644
> --- a/Documentation/devicetree/bindings/usb/omap-usb.txt
> +++ b/Documentation/devicetree/bindings/usb/omap-usb.txt
> @@ -53,6 +53,11 @@ OMAP DWC3 GLUE
> It should be set to "1" for HW mode and "2" for SW mode.
> - ranges: the child address space are mapped 1:1 onto the parent address space
>
> +Optional Properties:
> + - extcon : phandle for the extcon device omap dwc3 uses to detect
> + connect/disconnect events.
> + - vbus-supply : phandle to the regulator device tree node if needed.
> +
> Sub-nodes:
> The dwc3 core should be added as subnode to omap dwc3 glue.
> - dwc3 :
> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
> index 757aa18..08a9fab 100644
> --- a/drivers/usb/dwc3/Kconfig
> +++ b/drivers/usb/dwc3/Kconfig
> @@ -1,6 +1,7 @@
> config USB_DWC3
> tristate "DesignWare USB3 DRD Core Support"
> depends on (USB || USB_GADGET) && GENERIC_HARDIRQS
> + depends on EXTCON
> select USB_XHCI_PLATFORM if USB_SUPPORT && USB_XHCI_HCD
> help
> Say Y or M here if your system has a Dual Role SuperSpeed
> diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
> index f8f76e6..80b5780 100644
> --- a/drivers/usb/dwc3/dwc3-omap.c
> +++ b/drivers/usb/dwc3/dwc3-omap.c
> @@ -43,13 +43,15 @@
> #include <linux/spinlock.h>
> #include <linux/platform_device.h>
> #include <linux/platform_data/dwc3-omap.h>
> -#include <linux/usb/dwc3-omap.h>
> #include <linux/pm_runtime.h>
> #include <linux/dma-mapping.h>
> #include <linux/ioport.h>
> #include <linux/io.h>
> #include <linux/of.h>
> #include <linux/of_platform.h>
> +#include <linux/extcon.h>
> +#include <linux/extcon/of_extcon.h>
> +#include <linux/regulator/consumer.h>
>
> #include <linux/usb/otg.h>
>
> @@ -124,9 +126,21 @@ struct dwc3_omap {
> u32 utmi_otg_status;
>
> u32 dma_status:1;
> +
> + struct extcon_specific_cable_nb extcon_vbus_dev;
> + struct extcon_specific_cable_nb extcon_id_dev;
> + struct notifier_block vbus_nb;
> + struct notifier_block id_nb;
> +
> + struct regulator *vbus_reg;
> };
>
> -static struct dwc3_omap *_omap;
> +enum omap_dwc3_vbus_id_status {
> + OMAP_DWC3_ID_FLOAT,
> + OMAP_DWC3_ID_GROUND,
> + OMAP_DWC3_VBUS_OFF,
> + OMAP_DWC3_VBUS_VALID,
> +};
>
> static inline u32 dwc3_omap_readl(void __iomem *base, u32 offset)
> {
> @@ -138,18 +152,23 @@ static inline void dwc3_omap_writel(void __iomem *base, u32 offset, u32 value)
> writel(value, base + offset);
> }
>
> -int dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
> +static void dwc3_omap_set_mailbox(struct dwc3_omap *omap,
> + enum omap_dwc3_vbus_id_status status)
> {
> - u32 val;
> - struct dwc3_omap *omap = _omap;
> -
> - if (!omap)
> - return -EPROBE_DEFER;
> + int ret;
> + u32 val;
>
> switch (status) {
> case OMAP_DWC3_ID_GROUND:
> dev_dbg(omap->dev, "ID GND\n");
>
> + if (omap->vbus_reg) {
> + ret = regulator_enable(omap->vbus_reg);
> + if (ret) {
> + dev_dbg(omap->dev, "regulator enable failed\n");
> + return;
> + }
> + }
> val = dwc3_omap_readl(omap->base, USBOTGSS_UTMI_OTG_STATUS);
> val &= ~(USBOTGSS_UTMI_OTG_STATUS_IDDIG
> | USBOTGSS_UTMI_OTG_STATUS_VBUSVALID
> @@ -172,6 +191,9 @@ int dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
> break;
>
> case OMAP_DWC3_ID_FLOAT:
> + if (omap->vbus_reg)
> + regulator_disable(omap->vbus_reg);
> +
> case OMAP_DWC3_VBUS_OFF:
> dev_dbg(omap->dev, "VBUS Disconnect\n");
>
> @@ -185,12 +207,9 @@ int dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
> break;
>
> default:
> - dev_dbg(omap->dev, "ID float\n");
> + dev_dbg(omap->dev, "invalid state\n");
> }
> -
> - return 0;
> }
> -EXPORT_SYMBOL_GPL(dwc3_omap_mailbox);
>
> static irqreturn_t dwc3_omap_interrupt(int irq, void *_omap)
> {
> @@ -282,6 +301,32 @@ static void dwc3_omap_disable_irqs(struct dwc3_omap *omap)
>
> static u64 dwc3_omap_dma_mask = DMA_BIT_MASK(32);
>
> +static int dwc3_omap_id_notifier(struct notifier_block *nb,
> + unsigned long event, void *ptr)
> +{
> + struct dwc3_omap *omap = container_of(nb, struct dwc3_omap, id_nb);
> +
> + if (event)
> + dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_GROUND);
> + else
> + dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_FLOAT);
> +
> + return NOTIFY_DONE;
> +}
> +
> +static int dwc3_omap_vbus_notifier(struct notifier_block *nb,
> + unsigned long event, void *ptr)
> +{
> + struct dwc3_omap *omap = container_of(nb, struct dwc3_omap, vbus_nb);
> +
> + if (event)
> + dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_VALID);
> + else
> + dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_OFF);
> +
> + return NOTIFY_DONE;
> +}
> +
> static int dwc3_omap_probe(struct platform_device *pdev)
> {
> struct device_node *node = pdev->dev.of_node;
> @@ -289,6 +334,8 @@ static int dwc3_omap_probe(struct platform_device *pdev)
> struct dwc3_omap *omap;
> struct resource *res;
> struct device *dev = &pdev->dev;
> + struct extcon_dev *edev;
> + struct regulator *vbus_reg = NULL;
>
> int ret = -ENOMEM;
> int irq;
> @@ -330,19 +377,22 @@ static int dwc3_omap_probe(struct platform_device *pdev)
> return -ENOMEM;
> }
>
> + if (of_property_read_bool(node, "vbus-supply")) {
> + vbus_reg = devm_regulator_get(dev, "vbus");
> + if (IS_ERR(vbus_reg)) {
> + dev_err(dev, "vbus init failed\n");
> + return PTR_ERR(vbus_reg);
> + }
> + }
> +
> spin_lock_init(&omap->lock);
>
> omap->dev = dev;
> omap->irq = irq;
> omap->base = base;
> + omap->vbus_reg = vbus_reg;
> dev->dma_mask = &dwc3_omap_dma_mask;
>
> - /*
> - * REVISIT if we ever have two instances of the wrapper, we will be
> - * in big trouble
> - */
> - _omap = omap;
> -
> pm_runtime_enable(dev);
> ret = pm_runtime_get_sync(dev);
> if (ret < 0) {
> @@ -381,14 +431,47 @@ static int dwc3_omap_probe(struct platform_device *pdev)
>
> dwc3_omap_enable_irqs(omap);
>
> + if (of_property_read_bool(node, "extcon")) {
> + edev = of_extcon_get_extcon_dev(dev, 0);
> + if (IS_ERR(edev)) {
> + dev_vdbg(dev, "couldn't get extcon device\n");
> + ret = PTR_ERR(edev);
> + goto err2;
> + }
> +
> + omap->vbus_nb.notifier_call = dwc3_omap_vbus_notifier;
> + ret = extcon_register_interest(&omap->extcon_vbus_dev,
> + edev->name, "USB", &omap->vbus_nb);
> + if (ret < 0)
> + dev_vdbg(dev,
> + "extcon register interest of *USB* failed\n");
> + omap->id_nb.notifier_call = dwc3_omap_id_notifier;
> + ret = extcon_register_interest(&omap->extcon_id_dev, edev->name,
> + "USB-HOST", &omap->id_nb);
> + if (ret < 0)
> + dev_vdbg(dev,
> + "extcon register interest of *USB-HOST* failed\n");
> +
> + if (extcon_get_cable_state(edev, "USB") == true)
> + dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_VALID);
> + if (extcon_get_cable_state(edev, "USB-HOST") == true)
> + dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_GROUND);
> + }
> +
> ret = of_platform_populate(node, NULL, NULL, dev);
> if (ret) {
> dev_err(&pdev->dev, "failed to create dwc3 core\n");
> - goto err2;
> + goto err3;
> }
>
> return 0;
>
> +err3:
> + if (omap->extcon_vbus_dev.edev)
> + extcon_unregister_interest(&omap->extcon_vbus_dev);
> + if (omap->extcon_id_dev.edev)
> + extcon_unregister_interest(&omap->extcon_id_dev);
> +
> err2:
> dwc3_omap_disable_irqs(omap);
>
> @@ -405,6 +488,10 @@ static int dwc3_omap_remove(struct platform_device *pdev)
> {
> struct dwc3_omap *omap = platform_get_drvdata(pdev);
>
> + if (omap->extcon_vbus_dev.edev)
> + extcon_unregister_interest(&omap->extcon_vbus_dev);
> + if (omap->extcon_id_dev.edev)
> + extcon_unregister_interest(&omap->extcon_id_dev);
> dwc3_omap_disable_irqs(omap);
> pm_runtime_put_sync(&pdev->dev);
> pm_runtime_disable(&pdev->dev);
> diff --git a/include/linux/usb/dwc3-omap.h b/include/linux/usb/dwc3-omap.h
> deleted file mode 100644
> index 5615f4d..0000000
>

I have below some fixes for indentation and applied it (extcon-for-palmas branch).
- dev_vdbg(dev,
- "extcon register interest of *USB* failed\n");
+ dev_vdbg(dev, "failed to register notifier for USB\n");
omap->id_nb.notifier_call = dwc3_omap_id_notifier;
ret = extcon_register_interest(&omap->extcon_id_dev, edev->name,
"USB-HOST", &omap->id_nb);
if (ret < 0)
dev_vdbg(dev,
- "extcon register interest of *USB-HOST* failed\n");
+ "failed to register notifier for USB-HOST\n");

if (extcon_get_cable_state(edev, "USB") == true)
dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_VALID);

You can check it on following git repository.
- http://git.kernel.org/cgit/linux/kernel/git/chanwoo/extcon.git/commit/?h=extcon-for-palmas&id=bd84f70d42b867dfce61f961fb1c50d22e3ab4a8

And, I have plan to move your patch from extcon-for-palmas to extcon-next branch
after below patch on usb.git is applied on v3.11

usb: dwc3: omap: improve error handling of dwc3_omap_probe
- https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?h=next&id=594daba1bcb0510cdc9dccfbab9e6fd5d9cc94e6
- git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git (next branch)

Thanks,
Chanwoo Choi