Re: [PATCH v4 1/2] extcon: palmas: Support GPIO based USB ID detection
From: Lee Jones
Date: Mon Aug 10 2015 - 04:36:05 EST
On Mon, 03 Aug 2015, Roger Quadros wrote:
> Some palmas based chip variants do not have OTG based ID logic.
> For these variants we rely on GPIO based USB ID detection.
>
> These chips do have VBUS comparator for VBUS detection so we
> continue to use the old way of detecting VBUS.
>
> Acked-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> ---
> v4: updated gpio debounce logic to use delayed_workqueue.
>
> .../devicetree/bindings/extcon/extcon-palmas.txt | 5 +-
> drivers/extcon/extcon-palmas.c | 129 ++++++++++++++++++---
> drivers/extcon/extcon-usb-gpio.c | 1 +
> include/linux/mfd/palmas.h | 7 ++
> 4 files changed, 126 insertions(+), 16 deletions(-)
Acked-by: Lee Jones <lee.jones@xxxxxxxxxx>
> diff --git a/Documentation/devicetree/bindings/extcon/extcon-palmas.txt b/Documentation/devicetree/bindings/extcon/extcon-palmas.txt
> index 45414bb..f61d5af 100644
> --- a/Documentation/devicetree/bindings/extcon/extcon-palmas.txt
> +++ b/Documentation/devicetree/bindings/extcon/extcon-palmas.txt
> @@ -10,8 +10,11 @@ Required Properties:
>
> Optional Properties:
> - ti,wakeup : To enable the wakeup comparator in probe
> - - ti,enable-id-detection: Perform ID detection.
> + - ti,enable-id-detection: Perform ID detection. If id-gpio is specified
> + it performs id-detection using GPIO else using OTG core.
> - ti,enable-vbus-detection: Perform VBUS detection.
> + - id-gpio: gpio for GPIO ID detection. See gpio binding.
> + - debounce-delay-ms: debounce delay for GPIO ID pin in milliseconds.
>
> palmas-usb {
> compatible = "ti,twl6035-usb", "ti,palmas-usb";
> diff --git a/drivers/extcon/extcon-palmas.c b/drivers/extcon/extcon-palmas.c
> index 8933e7e..662e917 100644
> --- a/drivers/extcon/extcon-palmas.c
> +++ b/drivers/extcon/extcon-palmas.c
> @@ -28,6 +28,10 @@
> #include <linux/mfd/palmas.h>
> #include <linux/of.h>
> #include <linux/of_platform.h>
> +#include <linux/of_gpio.h>
> +#include <linux/workqueue.h>
> +
> +#define USB_GPIO_DEBOUNCE_MS 20 /* ms */
>
> static const unsigned int palmas_extcon_cable[] = {
> EXTCON_USB,
> @@ -118,19 +122,54 @@ static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
> return IRQ_HANDLED;
> }
>
> +static void palmas_gpio_id_detect(struct work_struct *work)
> +{
> + int id;
> + struct palmas_usb *palmas_usb = container_of(to_delayed_work(work),
> + struct palmas_usb,
> + wq_detectid);
> + struct extcon_dev *edev = palmas_usb->edev;
> +
> + if (!palmas_usb->id_gpiod)
> + return;
> +
> + id = gpiod_get_value_cansleep(palmas_usb->id_gpiod);
> +
> + if (id) {
> + extcon_set_cable_state_(edev, EXTCON_USB_HOST, false);
> + dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
> + } else {
> + extcon_set_cable_state_(edev, EXTCON_USB_HOST, true);
> + dev_info(palmas_usb->dev, "USB-HOST cable is attached\n");
> + }
> +}
> +
> +static irqreturn_t palmas_gpio_id_irq_handler(int irq, void *_palmas_usb)
> +{
> + struct palmas_usb *palmas_usb = _palmas_usb;
> +
> + queue_delayed_work(system_power_efficient_wq, &palmas_usb->wq_detectid,
> + palmas_usb->sw_debounce_jiffies);
> +
> + return IRQ_HANDLED;
> +}
> +
> static void palmas_enable_irq(struct palmas_usb *palmas_usb)
> {
> palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
> PALMAS_USB_VBUS_CTRL_SET,
> PALMAS_USB_VBUS_CTRL_SET_VBUS_ACT_COMP);
>
> - palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
> - PALMAS_USB_ID_CTRL_SET, PALMAS_USB_ID_CTRL_SET_ID_ACT_COMP);
> + if (palmas_usb->enable_id_detection) {
> + palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
> + PALMAS_USB_ID_CTRL_SET,
> + PALMAS_USB_ID_CTRL_SET_ID_ACT_COMP);
>
> - palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
> - PALMAS_USB_ID_INT_EN_HI_SET,
> - PALMAS_USB_ID_INT_EN_HI_SET_ID_GND |
> - PALMAS_USB_ID_INT_EN_HI_SET_ID_FLOAT);
> + palmas_write(palmas_usb->palmas, PALMAS_USB_OTG_BASE,
> + PALMAS_USB_ID_INT_EN_HI_SET,
> + PALMAS_USB_ID_INT_EN_HI_SET_ID_GND |
> + PALMAS_USB_ID_INT_EN_HI_SET_ID_FLOAT);
> + }
>
> if (palmas_usb->enable_vbus_detection)
> palmas_vbus_irq_handler(palmas_usb->vbus_irq, palmas_usb);
> @@ -169,20 +208,36 @@ static int palmas_usb_probe(struct platform_device *pdev)
> palmas_usb->wakeup = pdata->wakeup;
> }
>
> + palmas_usb->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id");
> + if (IS_ERR(palmas_usb->id_gpiod)) {
> + dev_err(&pdev->dev, "failed to get id gpio\n");
> + return PTR_ERR(palmas_usb->id_gpiod);
> + }
> +
> + if (palmas_usb->enable_id_detection && palmas_usb->id_gpiod) {
> + palmas_usb->enable_id_detection = false;
> + palmas_usb->enable_gpio_id_detection = true;
> + }
> +
> + if (palmas_usb->enable_gpio_id_detection) {
> + u32 debounce;
> +
> + if (of_property_read_u32(node, "debounce-delay-ms", &debounce))
> + debounce = USB_GPIO_DEBOUNCE_MS;
> +
> + status = gpiod_set_debounce(palmas_usb->id_gpiod,
> + debounce * 1000);
> + if (status < 0)
> + palmas_usb->sw_debounce_jiffies = msecs_to_jiffies(debounce);
> + }
> +
> + INIT_DELAYED_WORK(&palmas_usb->wq_detectid, palmas_gpio_id_detect);
> +
> palmas->usb = palmas_usb;
> palmas_usb->palmas = palmas;
>
> palmas_usb->dev = &pdev->dev;
>
> - palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
> - PALMAS_ID_OTG_IRQ);
> - palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
> - PALMAS_ID_IRQ);
> - palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
> - PALMAS_VBUS_OTG_IRQ);
> - palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
> - PALMAS_VBUS_IRQ);
> -
> palmas_usb_wakeup(palmas, palmas_usb->wakeup);
>
> platform_set_drvdata(pdev, palmas_usb);
> @@ -201,6 +256,10 @@ static int palmas_usb_probe(struct platform_device *pdev)
> }
>
> if (palmas_usb->enable_id_detection) {
> + palmas_usb->id_otg_irq = regmap_irq_get_virq(palmas->irq_data,
> + PALMAS_ID_OTG_IRQ);
> + palmas_usb->id_irq = regmap_irq_get_virq(palmas->irq_data,
> + PALMAS_ID_IRQ);
> status = devm_request_threaded_irq(palmas_usb->dev,
> palmas_usb->id_irq,
> NULL, palmas_id_irq_handler,
> @@ -212,9 +271,33 @@ static int palmas_usb_probe(struct platform_device *pdev)
> palmas_usb->id_irq, status);
> return status;
> }
> + } else if (palmas_usb->enable_gpio_id_detection) {
> + palmas_usb->gpio_id_irq = gpiod_to_irq(palmas_usb->id_gpiod);
> + if (palmas_usb->gpio_id_irq < 0) {
> + dev_err(&pdev->dev, "failed to get id irq\n");
> + return palmas_usb->gpio_id_irq;
> + }
> + status = devm_request_threaded_irq(&pdev->dev,
> + palmas_usb->gpio_id_irq,
> + NULL,
> + palmas_gpio_id_irq_handler,
> + IRQF_TRIGGER_RISING |
> + IRQF_TRIGGER_FALLING |
> + IRQF_ONESHOT,
> + "palmas_usb_id",
> + palmas_usb);
> + if (status < 0) {
> + dev_err(&pdev->dev,
> + "failed to request handler for id irq\n");
> + return status;
> + }
> }
>
> if (palmas_usb->enable_vbus_detection) {
> + palmas_usb->vbus_otg_irq = regmap_irq_get_virq(palmas->irq_data,
> + PALMAS_VBUS_OTG_IRQ);
> + palmas_usb->vbus_irq = regmap_irq_get_virq(palmas->irq_data,
> + PALMAS_VBUS_IRQ);
> status = devm_request_threaded_irq(palmas_usb->dev,
> palmas_usb->vbus_irq, NULL,
> palmas_vbus_irq_handler,
> @@ -229,10 +312,21 @@ static int palmas_usb_probe(struct platform_device *pdev)
> }
>
> palmas_enable_irq(palmas_usb);
> + /* perform initial detection */
> + palmas_gpio_id_detect(&palmas_usb->wq_detectid.work);
> device_set_wakeup_capable(&pdev->dev, true);
> return 0;
> }
>
> +static int palmas_usb_remove(struct platform_device *pdev)
> +{
> + struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
> +
> + cancel_delayed_work_sync(&palmas_usb->wq_detectid);
> +
> + return 0;
> +}
> +
> #ifdef CONFIG_PM_SLEEP
> static int palmas_usb_suspend(struct device *dev)
> {
> @@ -243,6 +337,8 @@ static int palmas_usb_suspend(struct device *dev)
> enable_irq_wake(palmas_usb->vbus_irq);
> if (palmas_usb->enable_id_detection)
> enable_irq_wake(palmas_usb->id_irq);
> + if (palmas_usb->enable_gpio_id_detection)
> + enable_irq_wake(palmas_usb->gpio_id_irq);
> }
> return 0;
> }
> @@ -256,6 +352,8 @@ static int palmas_usb_resume(struct device *dev)
> disable_irq_wake(palmas_usb->vbus_irq);
> if (palmas_usb->enable_id_detection)
> disable_irq_wake(palmas_usb->id_irq);
> + if (palmas_usb->enable_gpio_id_detection)
> + disable_irq_wake(palmas_usb->gpio_id_irq);
> }
> return 0;
> };
> @@ -273,6 +371,7 @@ static const struct of_device_id of_palmas_match_tbl[] = {
>
> static struct platform_driver palmas_usb_driver = {
> .probe = palmas_usb_probe,
> + .remove = palmas_usb_remove,
> .driver = {
> .name = "palmas-usb",
> .of_match_table = of_palmas_match_tbl,
> diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c
> index a2a4453..2b2fecf 100644
> --- a/drivers/extcon/extcon-usb-gpio.c
> +++ b/drivers/extcon/extcon-usb-gpio.c
> @@ -15,6 +15,7 @@
> */
>
> #include <linux/extcon.h>
> +#include <linux/gpio.h>
> #include <linux/gpio/consumer.h>
> #include <linux/init.h>
> #include <linux/interrupt.h>
> diff --git a/include/linux/mfd/palmas.h b/include/linux/mfd/palmas.h
> index bb270bd..13e1d96 100644
> --- a/include/linux/mfd/palmas.h
> +++ b/include/linux/mfd/palmas.h
> @@ -21,6 +21,7 @@
> #include <linux/regmap.h>
> #include <linux/regulator/driver.h>
> #include <linux/extcon.h>
> +#include <linux/of_gpio.h>
> #include <linux/usb/phy_companion.h>
>
> #define PALMAS_NUM_CLIENTS 3
> @@ -551,10 +552,16 @@ struct palmas_usb {
> int vbus_otg_irq;
> int vbus_irq;
>
> + int gpio_id_irq;
> + struct gpio_desc *id_gpiod;
> + unsigned long sw_debounce_jiffies;
> + struct delayed_work wq_detectid;
> +
> enum palmas_usb_state linkstat;
> int wakeup;
> bool enable_vbus_detection;
> bool enable_id_detection;
> + bool enable_gpio_id_detection;
> };
>
> #define comparator_to_palmas(x) container_of((x), struct palmas_usb, comparator)
--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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