/* * Intel INT3496 ACPI device extcon driver * * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com> * * Based on android x86 kernel code which is: * * Copyright (c) 2014, Intel Corporation. * Author: David Cohen <david.a.cohen@linux.intel.com> * * 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-provider.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 const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false }; static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false }; static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false }; static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = { /* * Some platforms have a bug in ACPI GPIO description making IRQ * GPIO to be output only. Ask the GPIO core to ignore this limit. */ { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION }, { "vbus-gpios", &vbus_gpios, 1 }, { "mux-gpios", &mux_gpios, 1 }, { }, }; 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; ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios); if (ret) { dev_err(dev, "can't add GPIO ACPI mapping\n"); return 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(dev, "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 data->usb_id_irq; } data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", 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(dev, "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; } /* process id-pin so that we start with the right status */ queue_delayed_work(system_wq, &data->work, 0); flush_delayed_work(&data->work); 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 const 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@redhat.com>"); MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver"); MODULE_LICENSE("GPL");