[RFC v4 4/7] extcon: usb-gpio: Add support for VBUS detection
Roger Quadros
rogerq at ti.com
Thu Jun 9 01:38:26 PDT 2016
Hi,
On 08/06/16 16:48, Krzysztof Kozlowski wrote:
> 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 at samsung.com>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
>
> ---
>
> 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);
> + }
What happens if either id_gpiod or vbus_gpiod is present?
As per the DT binding document
"In general we have three cases:
1. If VBUS and ID gpios are present we pass them as is
USB-HOST = !ID, USB = VBUS
2. If only VBUS gpio is present we assume that ID pin is always High.
USB-HOST = false, USB = VBUS.
3. If only ID pin is available we infer the VBUS pin states based on ID.
USB-HOST = !ID, USB = ID"
So do you want to be consistent and infer VBUS and ID states based on the other?
> }
>
> 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
>
>
--
cheers,
-roger
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