Re: [PATCH] extcon: usb-gpio: Add VBUS detection support

From: Roger Quadros
Date: Fri Oct 07 2016 - 05:19:11 EST


Hi Chanwoo,


On 27/09/16 08:48, Peter Chen wrote:
> On Tue, Sep 20, 2016 at 05:53:55PM +0300, Roger Quadros wrote:
>> 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 <rogerq@xxxxxx>

Can you please pick this one for v4.9? Thanks.

cheers,
-roger

>> ---
>> .../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);
>> --
>
> Reviewed-by: Peter Chen <peter.chen@xxxxxxx>
>