Re: [PATCH v2] extcon: int3496: Add Intel INT3496 ACPI device extcon driver

From: Chanwoo Choi
Date: Fri Dec 23 2016 - 12:39:16 EST

Hi Hans,

I have two minor comment on below.
But, after fixing it by myself, Applied it on extcon-next branch for v4.11.

2016-12-21 20:20 GMT+09:00 Hans de Goede <hdegoede@xxxxxxxxxx>:
> From: David Cohen <david.a.cohen@xxxxxxxxx>
>
> Add an extcon driver for USB OTG ports controlled by an Intel INT3496
> ACPI device (e.g. Baytrail, Cherrytrail devices).
>
> Signed-off-by: David Cohen <david.a.cohen@xxxxxxxxx>
> [hdgoede@xxxxxxxxxx: Port to current kernel, cleanup, submit upstream]
> [hdgoede@xxxxxxxxxx: Add Documentation/extcon/intel-int3496.txt]
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> ---
> Changes in v2:
> -Rename to extcon-intel-int3496
> -Add documentation: Documentation/extcon/intel-int3496.txt
> -Fold usb_otg_set_port() into usb_otg_do_usb_id()
> -Unify / cleanup error messages
> ---
> Documentation/extcon/intel-int3496.txt | 22 ++++
> drivers/extcon/Kconfig | 10 ++
> drivers/extcon/Makefile | 1 +
> drivers/extcon/extcon-intel-int3496.c | 179 +++++++++++++++++++++++++++++++++
> 4 files changed, 212 insertions(+)
> create mode 100644 Documentation/extcon/intel-int3496.txt
> create mode 100644 drivers/extcon/extcon-intel-int3496.c
>
> diff --git a/Documentation/extcon/intel-int3496.txt b/Documentation/extcon/intel-int3496.txt
> new file mode 100644
> index 0000000..af0b366
> --- /dev/null
> +++ b/Documentation/extcon/intel-int3496.txt
> @@ -0,0 +1,22 @@
> +Intel INT3496 ACPI device extcon driver documentation
> +-----------------------------------------------------
> +
> +The Intel INT3496 ACPI device extcon driver is a driver for ACPI
> +devices with an acpi-id of INT3496, such as found for example on
> +Intel Baytrail and Cherrytrail tablets.
> +
> +This ACPI device describes how the OS can read the id-pin of the devices'
> +USB-otg port, as well as how it optionally can enable Vbus output on the
> +otg port and how it can optionally control the muxing of the data pins
> +between an USB host and an USB peripheral controller.
> +
> +The ACPI devices exposes this functionality by returning an array with up
> +to 3 gpio descriptors from its ACPI _CRS (Current Resource Settings) call:
> +
> +Index 0: The input gpio for the id-pin, this is always present and valid
> +Index 1: The output gpio for enabling Vbus output from the device to the otg
> + port, write 1 to enable the Vbus output (this gpio descriptor may
> + be absent or invalid)
> +Index 2: The output gpio for muxing of the data pins between the USB host and
> + the USB peripheral controller, write 1 to mux to the peripheral
> + controller
> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
> index 04788d9..1ed3860 100644
> --- a/drivers/extcon/Kconfig
> +++ b/drivers/extcon/Kconfig
> @@ -35,6 +35,16 @@ config EXTCON_AXP288
> Say Y here to enable support for USB peripheral detection
> and USB MUX switching by X-Power AXP288 PMIC.
>
> +config EXTCON_INTEL_INT3496

Need to reorder alphabetically. EXTCON_INTEL_INT3496 should be
positioned on below EXTCON_GPIO.

> + tristate "Intel INT3496 ACPI device extcon driver"
> + depends on GPIOLIB && ACPI
> + help
> + Say Y here to enable extcon support for USB OTG ports controlled by
> + an Intel INT3496 ACPI device.
> +
> + This ACPI device is typically found on Intel Baytrail or Cherrytrail
> + based tablets, or other Baytrail / Cherrytrail devices.

The upper two line used the 'space' without 'tab'.

> +
> config EXTCON_GPIO
> tristate "GPIO extcon support"
> depends on GPIOLIB || COMPILE_TEST
> diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
> index 31a0a99..237ac3f 100644
> --- a/drivers/extcon/Makefile
> +++ b/drivers/extcon/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_EXTCON_ADC_JACK) += extcon-adc-jack.o
> obj-$(CONFIG_EXTCON_ARIZONA) += extcon-arizona.o
> obj-$(CONFIG_EXTCON_AXP288) += extcon-axp288.o
> obj-$(CONFIG_EXTCON_GPIO) += extcon-gpio.o
> +obj-$(CONFIG_EXTCON_INTEL_INT3496) += extcon-intel-int3496.o
> obj-$(CONFIG_EXTCON_MAX14577) += extcon-max14577.o
> obj-$(CONFIG_EXTCON_MAX3355) += extcon-max3355.o
> obj-$(CONFIG_EXTCON_MAX77693) += extcon-max77693.o
> diff --git a/drivers/extcon/extcon-intel-int3496.c b/drivers/extcon/extcon-intel-int3496.c
> new file mode 100644
> index 0000000..a3131b0
> --- /dev/null
> +++ b/drivers/extcon/extcon-intel-int3496.c
> @@ -0,0 +1,179 @@
> +/*
> + * Intel INT3496 ACPI device extcon driver
> + *
> + * Copyright (c) 2016 Hans de Goede <hdegoede@xxxxxxxxxx>
> + *
> + * Based on android x86 kernel code which is:
> + *
> + * Copyright (c) 2014, Intel Corporation.
> + * Author: David Cohen <david.a.cohen@xxxxxxxxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/extcon.h>
> +#include <linux/gpio.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#define INT3496_GPIO_USB_ID 0
> +#define INT3496_GPIO_VBUS_EN 1
> +#define INT3496_GPIO_USB_MUX 2
> +#define DEBOUNCE_TIME msecs_to_jiffies(50)
> +
> +struct int3496_data {
> + struct device *dev;
> + struct extcon_dev *edev;
> + struct delayed_work work;
> + struct gpio_desc *gpio_usb_id;
> + struct gpio_desc *gpio_vbus_en;
> + struct gpio_desc *gpio_usb_mux;
> + int usb_id_irq;
> +};
> +
> +static const unsigned int int3496_cable[] = {
> + EXTCON_USB_HOST,
> + EXTCON_NONE,
> +};
> +
> +static void int3496_do_usb_id(struct work_struct *work)
> +{
> + struct int3496_data *data =
> + container_of(work, struct int3496_data, work.work);
> + int id = gpiod_get_value_cansleep(data->gpio_usb_id);
> +
> + /* id == 1: PERIPHERAL, id == 0: HOST */
> + dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
> +
> + /*
> + * Peripheral: set USB mux to peripheral and disable VBUS
> + * Host: set USB mux to host and enable VBUS
> + */
> + if (!IS_ERR(data->gpio_usb_mux))
> + gpiod_direction_output(data->gpio_usb_mux, id);
> +
> + if (!IS_ERR(data->gpio_vbus_en))
> + gpiod_direction_output(data->gpio_vbus_en, !id);
> +
> + extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
> +}
> +
> +static irqreturn_t int3496_thread_isr(int irq, void *priv)
> +{
> + struct int3496_data *data = priv;
> +
> + /* Let the pin settle before processing it */
> + mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int int3496_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct int3496_data *data;
> + int ret;
> +
> + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->dev = dev;
> + INIT_DELAYED_WORK(&data->work, int3496_do_usb_id);
> +
> + data->gpio_usb_id = devm_gpiod_get_index(dev, "id",
> + INT3496_GPIO_USB_ID,
> + GPIOD_IN);
> + if (IS_ERR(data->gpio_usb_id)) {
> + ret = PTR_ERR(data->gpio_usb_id);
> + dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
> + return ret;
> + }
> +
> + data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
> + if (data->usb_id_irq <= 0) {
> + dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
> + return -EINVAL;
> + }
> +
> + data->gpio_vbus_en = devm_gpiod_get_index(dev, "vbus en",
> + INT3496_GPIO_VBUS_EN,
> + GPIOD_ASIS);
> + if (IS_ERR(data->gpio_vbus_en))
> + dev_info(dev, "can't request VBUS EN GPIO\n");
> +
> + data->gpio_usb_mux = devm_gpiod_get_index(dev, "usb mux",
> + INT3496_GPIO_USB_MUX,
> + GPIOD_ASIS);
> + if (IS_ERR(data->gpio_usb_mux))
> + dev_info(dev, "can't request USB MUX GPIO\n");
> +
> + /* register extcon device */
> + data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
> + if (IS_ERR(data->edev))
> + return -ENOMEM;
> +
> + ret = devm_extcon_dev_register(dev, data->edev);
> + if (ret < 0) {
> + dev_err(dev, "can't register extcon device: %d\n", ret);
> + return ret;
> + }
> +
> + ret = devm_request_threaded_irq(dev, data->usb_id_irq,
> + NULL, int3496_thread_isr,
> + IRQF_SHARED | IRQF_ONESHOT |
> + IRQF_TRIGGER_RISING |
> + IRQF_TRIGGER_FALLING,
> + dev_name(dev), data);
> + if (ret < 0) {
> + dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
> + return ret;
> + }
> +
> + /* queue initial processing of id-pin */
> + queue_delayed_work(system_wq, &data->work, 0);
> +
> + platform_set_drvdata(pdev, data);
> +
> + return 0;
> +}
> +
> +static int int3496_remove(struct platform_device *pdev)
> +{
> + struct int3496_data *data = platform_get_drvdata(pdev);
> +
> + devm_free_irq(&pdev->dev, data->usb_id_irq, data);
> + cancel_delayed_work_sync(&data->work);
> +
> + return 0;
> +}
> +
> +static struct acpi_device_id int3496_acpi_match[] = {
> + { "INT3496" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
> +
> +static struct platform_driver int3496_driver = {
> + .driver = {
> + .name = "intel-int3496",
> + .acpi_match_table = int3496_acpi_match,
> + },
> + .probe = int3496_probe,
> + .remove = int3496_remove,
> +};
> +
> +module_platform_driver(int3496_driver);
> +
> +MODULE_AUTHOR("Hans de Goede <hdegoede@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
> +MODULE_LICENSE("GPL");
> --
> 2.9.3
>



--
Best Regards,
Chanwoo Choi