[RFC v4 4/7] extcon: usb-gpio: Add support for VBUS detection

From: Krzysztof Kozlowski
Date: Wed Jun 08 2016 - 09:50:50 EST


Add VBUS pin detection support to extcon-usb-gpio driver for boards
which have both VBUS and ID pins, or only one of them.

The logic behind reporting USB and USB-HOST extcon cables is not
affected. The driver however will report extcon changes for USB-VBUS and
USB-ID.

Signed-off-by: Robert Baldyga <r.baldyga@xxxxxxxxxxx>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>

---

Some parts base on old Robert's patchset.
---
drivers/extcon/extcon-usb-gpio.c | 125 +++++++++++++++++++++++++++++++--------
1 file changed, 99 insertions(+), 26 deletions(-)

diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c
index a36aab007022..85b8a0ce5731 100644
--- a/drivers/extcon/extcon-usb-gpio.c
+++ b/drivers/extcon/extcon-usb-gpio.c
@@ -35,7 +35,9 @@ struct usb_extcon_info {
struct extcon_dev *edev;

struct gpio_desc *id_gpiod;
+ struct gpio_desc *vbus_gpiod;
int id_irq;
+ int vbus_irq;

unsigned long debounce_jiffies;
struct delayed_work wq_detcable;
@@ -44,6 +46,8 @@ struct usb_extcon_info {
static const unsigned int usb_extcon_cable[] = {
EXTCON_USB,
EXTCON_USB_HOST,
+ EXTCON_USB_ID,
+ EXTCON_USB_VBUS,
EXTCON_NONE,
};

@@ -55,7 +59,8 @@ static void usb_extcon_detect_cable(struct work_struct *work)
wq_detcable);

/* check ID and update cable state */
- id = gpiod_get_value_cansleep(info->id_gpiod);
+ id = info->id_gpiod ? gpiod_get_value_cansleep(info->id_gpiod) : 1;
+
if (id) {
/*
* ID = 1 means USB HOST cable detached.
@@ -73,6 +78,14 @@ static void usb_extcon_detect_cable(struct work_struct *work)
extcon_set_cable_state_(info->edev, EXTCON_USB, false);
extcon_set_cable_state_(info->edev, EXTCON_USB_HOST, true);
}
+
+ if (info->id_gpiod)
+ extcon_set_cable_state_(info->edev, EXTCON_USB_ID, id);
+ if (info->vbus_gpiod) {
+ int vbus = gpiod_get_value_cansleep(info->vbus_gpiod);
+
+ extcon_set_cable_state_(info->edev, EXTCON_USB_VBUS, vbus);
+ }
}

static irqreturn_t usb_irq_handler(int irq, void *dev_id)
@@ -100,9 +113,11 @@ static int usb_extcon_probe(struct platform_device *pdev)
return -ENOMEM;

info->dev = dev;
- info->id_gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);
- if (IS_ERR(info->id_gpiod)) {
- dev_err(dev, "failed to get ID GPIO\n");
+ info->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id", GPIOD_IN);
+ info->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",
+ GPIOD_IN);
+ if (!info->id_gpiod && !info->vbus_gpiod) {
+ dev_err(dev, "failed to get GPIOs\n");
return PTR_ERR(info->id_gpiod);
}

@@ -118,27 +133,54 @@ static int usb_extcon_probe(struct platform_device *pdev)
return ret;
}

- ret = gpiod_set_debounce(info->id_gpiod,
- USB_GPIO_DEBOUNCE_MS * 1000);
+ if (info->id_gpiod)
+ ret = gpiod_set_debounce(info->id_gpiod,
+ USB_GPIO_DEBOUNCE_MS * 1000);
+ if (!ret && info->vbus_gpiod) {
+ ret = gpiod_set_debounce(info->vbus_gpiod,
+ USB_GPIO_DEBOUNCE_MS * 1000);
+ if (ret < 0 && info->id_gpiod)
+ gpiod_set_debounce(info->vbus_gpiod, 0);
+ }
if (ret < 0)
info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS);

INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable);

- info->id_irq = gpiod_to_irq(info->id_gpiod);
- if (info->id_irq < 0) {
- dev_err(dev, "failed to get ID IRQ\n");
- return info->id_irq;
+ if (info->id_gpiod) {
+ info->id_irq = gpiod_to_irq(info->id_gpiod);
+ if (info->id_irq < 0) {
+ dev_err(dev, "failed to get ID IRQ\n");
+ return info->id_irq;
+ }
+ ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
+ usb_irq_handler,
+ IRQF_TRIGGER_RISING |
+ IRQF_TRIGGER_FALLING |
+ IRQF_ONESHOT,
+ pdev->name, info);
+ if (ret < 0) {
+ dev_err(dev, "failed to request handler for ID IRQ\n");
+ return ret;
+ }
}

- ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
- usb_irq_handler,
- IRQF_TRIGGER_RISING |
- IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
- pdev->name, info);
- if (ret < 0) {
- dev_err(dev, "failed to request handler for ID IRQ\n");
- return ret;
+ if (info->vbus_gpiod) {
+ info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
+ if (info->vbus_irq < 0) {
+ dev_err(dev, "failed to get VBUS IRQ\n");
+ return info->vbus_irq;
+ }
+ ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
+ usb_irq_handler,
+ IRQF_TRIGGER_RISING |
+ IRQF_TRIGGER_FALLING |
+ IRQF_ONESHOT,
+ pdev->name, info);
+ if (ret < 0) {
+ dev_err(dev, "failed to request handler for VBUS IRQ\n");
+ return ret;
+ }
}

platform_set_drvdata(pdev, info);
@@ -166,9 +208,16 @@ static int usb_extcon_suspend(struct device *dev)
int ret = 0;

if (device_may_wakeup(dev)) {
- ret = enable_irq_wake(info->id_irq);
- if (ret)
- return ret;
+ if (info->id_gpiod) {
+ ret = enable_irq_wake(info->id_irq);
+ if (ret)
+ return ret;
+ }
+ if (info->vbus_gpiod) {
+ ret = enable_irq_wake(info->vbus_irq);
+ if (ret)
+ goto err;
+ }
}

/*
@@ -176,8 +225,16 @@ static int usb_extcon_suspend(struct device *dev)
* as GPIOs used behind I2C subsystem might not be
* accessible until resume completes. So disable IRQ.
*/
- disable_irq(info->id_irq);
+ if (info->id_gpiod)
+ disable_irq(info->id_irq);
+ if (info->vbus_gpiod)
+ disable_irq(info->vbus_irq);
+
+ return ret;

+err:
+ if (info->id_gpiod)
+ disable_irq_wake(info->id_irq);
return ret;
}

@@ -187,17 +244,33 @@ static int usb_extcon_resume(struct device *dev)
int ret = 0;

if (device_may_wakeup(dev)) {
- ret = disable_irq_wake(info->id_irq);
- if (ret)
- return ret;
+ if (info->id_gpiod) {
+ ret = disable_irq_wake(info->id_irq);
+ if (ret)
+ return ret;
+ }
+ if (info->vbus_gpiod) {
+ ret = disable_irq_wake(info->vbus_irq);
+ if (ret)
+ goto err;
+ }
}

- enable_irq(info->id_irq);
+ if (info->id_gpiod)
+ enable_irq(info->id_irq);
+ if (info->vbus_gpiod)
+ enable_irq(info->vbus_irq);
+
if (!device_may_wakeup(dev))
queue_delayed_work(system_power_efficient_wq,
&info->wq_detcable, 0);

return ret;
+
+err:
+ if (info->id_gpiod)
+ enable_irq_wake(info->id_irq);
+ return ret;
}
#endif

--
1.9.1