Driver can now work with both ID and VBUS pins or either one of
them.
There can be the following 3 cases
1) Both ID and VBUS GPIOs are available:
ID = LOW -> USB_HOST active, USB inactive
ID = HIGH -> USB_HOST inactive, USB state is same as VBUS.
2) Only ID GPIO is available:
ID = LOW -> USB_HOST active, USB inactive
ID = HIGH -> USB_HOST inactive, USB active
3) Only VBUS GPIO is available:
VBUS = LOW -> USB_HOST inactive, USB inactive
VBUS = HIGH -> USB_HOST inactive, USB active
Signed-off-by: Roger Quadros <rog...@ti.com>
---
.../devicetree/bindings/extcon/extcon-usb-gpio.txt | 3 +
drivers/extcon/extcon-usb-gpio.c | 169 ++++++++++++++++-----
2 files changed, 132 insertions(+), 40 deletions(-)
diff --git a/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt
b/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt
index af0b903..dfc14f7 100644
--- a/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt
+++ b/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt
@@ -5,7 +5,10 @@ connected to a GPIO pin.
Required properties:
- compatible: Should be "linux,extcon-usb-gpio"
+
+Either one of id-gpio or vbus-gpio must be present. Both can be present as
well.
- id-gpio: gpio for USB ID pin. See gpio binding.
+- vbus-gpio: gpio for USB VBUS pin.
Example: Examples of extcon-usb-gpio node in dra7-evm.dts as listed below:
extcon_usb1 {
diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c
index a27d350..d589c5f 100644
--- a/drivers/extcon/extcon-usb-gpio.c
+++ b/drivers/extcon/extcon-usb-gpio.c
@@ -24,7 +24,6 @@
#include <linux/module.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
-#include <linux/pm_wakeirq.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/acpi.h>
@@ -36,7 +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;
@@ -48,31 +49,47 @@ static const unsigned int usb_extcon_cable[] = {
EXTCON_NONE,
};
+/*
+ * "USB" = VBUS and "USB-HOST" = !ID, so we have:
+ * Both "USB" and "USB-HOST" can't be set as active at the
+ * same time so if "USB-HOST" is active (i.e. ID is 0) we keep "USB" inactive
+ * even if VBUS is on.
+ *
+ * State | ID | VBUS
+ * ----------------------------------------
+ * [1] USB | H | H
+ * [2] none | H | L
+ * [3] USB-HOST | L | H
+ * [4] USB-HOST | L | L
+ *
+ * In case we have only one of these signals:
+ * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1.
+ * - ID only - we want to distinguish between [1] and [4], so VBUS = ID.
+*/
static void usb_extcon_detect_cable(struct work_struct *work)
{
- int id;
+ int id, vbus;
struct usb_extcon_info *info = container_of(to_delayed_work(work),
struct usb_extcon_info,
wq_detcable);
- /* check ID and update cable state */
- id = gpiod_get_value_cansleep(info->id_gpiod);
- if (id) {
- /*
- * ID = 1 means USB HOST cable detached.
- * As we don't have event for USB peripheral cable attached,
- * we simulate USB peripheral attach here.
- */
+ /* check ID and VBUS and update cable state */
+ id = info->id_gpiod ?
+ gpiod_get_value_cansleep(info->id_gpiod) : 1;
+ vbus = info->vbus_gpiod ?
+ gpiod_get_value_cansleep(info->vbus_gpiod) : id;
+
+ /* at first we clean states which are no longer active */
+ if (id)
extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
- extcon_set_state_sync(info->edev, EXTCON_USB, true);
- } else {
- /*
- * ID = 0 means USB HOST cable attached.
- * As we don't have event for USB peripheral cable detached,
- * we simulate USB peripheral detach here.
- */
+ if (!vbus)
extcon_set_state_sync(info->edev, EXTCON_USB, false);
+
+ if (!id) {
extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
+ } else {
+ if (vbus)
+ extcon_set_state_sync(info->edev, EXTCON_USB, true);
}
}
@@ -101,12 +118,21 @@ 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");
- return PTR_ERR(info->id_gpiod);
+ 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 -ENODEV;
}
+ if (IS_ERR(info->id_gpiod))
+ return PTR_ERR(info->id_gpiod);
+
+ if (IS_ERR(info->vbus_gpiod))
+ return PTR_ERR(info->vbus_gpiod);
+
info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
if (IS_ERR(info->edev)) {
dev_err(dev, "failed to allocate extcon device\n");
@@ -119,32 +145,56 @@ 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->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);
device_init_wakeup(dev, true);
- dev_pm_set_wake_irq(dev, info->id_irq);
/* Perform initial detection */
usb_extcon_detect_cable(&info->wq_detcable.work);
@@ -157,8 +207,6 @@ static int usb_extcon_remove(struct platform_device *pdev)
struct usb_extcon_info *info = platform_get_drvdata(pdev);
cancel_delayed_work_sync(&info->wq_detcable);
-
- dev_pm_clear_wake_irq(&pdev->dev);
device_init_wakeup(&pdev->dev, false);
return 0;
@@ -170,12 +218,32 @@ static int usb_extcon_suspend(struct device *dev)
struct usb_extcon_info *info = dev_get_drvdata(dev);
int ret = 0;
+ if (device_may_wakeup(dev)) {
+ 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) {
+ if (info->id_gpiod)
+ disable_irq_wake(info->id_irq);
+
+ return ret;
+ }
+ }
+ }
+
/*
* We don't want to process any IRQs after this point
* 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;
}
@@ -185,7 +253,28 @@ static int usb_extcon_resume(struct device *dev)
struct usb_extcon_info *info = dev_get_drvdata(dev);
int ret = 0;
- enable_irq(info->id_irq);
+ if (device_may_wakeup(dev)) {
+ 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) {
+ if (info->id_gpiod)
+ enable_irq_wake(info->id_irq);
+
+ return ret;
+ }
+ }
+ }
+
+ 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);
--
2.7.4
