drivers/extcon/extcon-intel-int3496.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Intel INT3496 ACPI device extcon driver
0004  *
0005  * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
0006  *
0007  * Based on android x86 kernel code which is:
0008  *
0009  * Copyright (c) 2014, Intel Corporation.
0010  * Author: David Cohen <david.a.cohen@linux.intel.com>
0011  */
0012
0013 #include <linux/acpi.h>
0014 #include <linux/devm-helpers.h>
0015 #include <linux/extcon-provider.h>
0016 #include <linux/gpio/consumer.h>
0017 #include <linux/interrupt.h>
0018 #include <linux/module.h>
0019 #include <linux/platform_device.h>
0020 #include <linux/regulator/consumer.h>
0021
0022 #define INT3496_GPIO_USB_ID 0
0023 #define INT3496_GPIO_VBUS_EN    1
0024 #define INT3496_GPIO_USB_MUX    2
0025 #define DEBOUNCE_TIME       msecs_to_jiffies(50)
0026
0027 struct int3496_data {
0028     struct device *dev;
0029     struct extcon_dev *edev;
0030     struct delayed_work work;
0031     struct gpio_desc *gpio_usb_id;
0032     struct gpio_desc *gpio_vbus_en;
0033     struct gpio_desc *gpio_usb_mux;
0034     struct regulator *vbus_boost;
0035     int usb_id_irq;
0036     bool vbus_boost_enabled;
0037 };
0038
0039 static const unsigned int int3496_cable[] = {
0040     EXTCON_USB_HOST,
0041     EXTCON_NONE,
0042 };
0043
0044 static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false };
0045 static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false };
0046 static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false };
0047
0048 static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = {
0049     /*
0050      * Some platforms have a bug in ACPI GPIO description making IRQ
0051      * GPIO to be output only. Ask the GPIO core to ignore this limit.
0052      */
0053     { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
0054     { "vbus-gpios", &vbus_gpios, 1 },
0055     { "mux-gpios", &mux_gpios, 1 },
0056     { },
0057 };
0058
0059 static void int3496_set_vbus_boost(struct int3496_data *data, bool enable)
0060 {
0061     int ret;
0062
0063     if (IS_ERR_OR_NULL(data->vbus_boost))
0064         return;
0065
0066     if (data->vbus_boost_enabled == enable)
0067         return;
0068
0069     if (enable)
0070         ret = regulator_enable(data->vbus_boost);
0071     else
0072         ret = regulator_disable(data->vbus_boost);
0073
0074     if (ret == 0)
0075         data->vbus_boost_enabled = enable;
0076     else
0077         dev_err(data->dev, "Error updating Vbus boost regulator: %d\n", ret);
0078 }
0079
0080 static void int3496_do_usb_id(struct work_struct *work)
0081 {
0082     struct int3496_data *data =
0083         container_of(work, struct int3496_data, work.work);
0084     int id = gpiod_get_value_cansleep(data->gpio_usb_id);
0085
0086     /* id == 1: PERIPHERAL, id == 0: HOST */
0087     dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
0088
0089     /*
0090      * Peripheral: set USB mux to peripheral and disable VBUS
0091      * Host: set USB mux to host and enable VBUS
0092      */
0093     if (!IS_ERR(data->gpio_usb_mux))
0094         gpiod_direction_output(data->gpio_usb_mux, id);
0095
0096     if (!IS_ERR(data->gpio_vbus_en))
0097         gpiod_direction_output(data->gpio_vbus_en, !id);
0098     else
0099         int3496_set_vbus_boost(data, !id);
0100
0101     extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
0102 }
0103
0104 static irqreturn_t int3496_thread_isr(int irq, void *priv)
0105 {
0106     struct int3496_data *data = priv;
0107
0108     /* Let the pin settle before processing it */
0109     mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
0110
0111     return IRQ_HANDLED;
0112 }
0113
0114 static int int3496_probe(struct platform_device *pdev)
0115 {
0116     struct device *dev = &pdev->dev;
0117     struct int3496_data *data;
0118     int ret;
0119
0120     if (has_acpi_companion(dev)) {
0121         ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios);
0122         if (ret) {
0123             dev_err(dev, "can't add GPIO ACPI mapping\n");
0124             return ret;
0125         }
0126     }
0127
0128     data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
0129     if (!data)
0130         return -ENOMEM;
0131
0132     data->dev = dev;
0133     ret = devm_delayed_work_autocancel(dev, &data->work, int3496_do_usb_id);
0134     if (ret)
0135         return ret;
0136
0137     data->gpio_usb_id =
0138         devm_gpiod_get(dev, "id", GPIOD_IN | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
0139     if (IS_ERR(data->gpio_usb_id)) {
0140         ret = PTR_ERR(data->gpio_usb_id);
0141         dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
0142         return ret;
0143     }
0144
0145     data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
0146     if (data->usb_id_irq < 0) {
0147         dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
0148         return data->usb_id_irq;
0149     }
0150
0151     data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS);
0152     if (IS_ERR(data->gpio_vbus_en)) {
0153         dev_dbg(dev, "can't request VBUS EN GPIO\n");
0154         data->vbus_boost = devm_regulator_get_optional(dev, "vbus");
0155     }
0156
0157     data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS);
0158     if (IS_ERR(data->gpio_usb_mux))
0159         dev_dbg(dev, "can't request USB MUX GPIO\n");
0160
0161     /* register extcon device */
0162     data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
0163     if (IS_ERR(data->edev))
0164         return -ENOMEM;
0165
0166     ret = devm_extcon_dev_register(dev, data->edev);
0167     if (ret < 0) {
0168         dev_err(dev, "can't register extcon device: %d\n", ret);
0169         return ret;
0170     }
0171
0172     ret = devm_request_threaded_irq(dev, data->usb_id_irq,
0173                     NULL, int3496_thread_isr,
0174                     IRQF_SHARED | IRQF_ONESHOT |
0175                     IRQF_TRIGGER_RISING |
0176                     IRQF_TRIGGER_FALLING,
0177                     dev_name(dev), data);
0178     if (ret < 0) {
0179         dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
0180         return ret;
0181     }
0182
0183     /* process id-pin so that we start with the right status */
0184     queue_delayed_work(system_wq, &data->work, 0);
0185     flush_delayed_work(&data->work);
0186
0187     platform_set_drvdata(pdev, data);
0188
0189     return 0;
0190 }
0191
0192 static const struct acpi_device_id int3496_acpi_match[] = {
0193     { "INT3496" },
0194     { }
0195 };
0196 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
0197
0198 static const struct platform_device_id int3496_ids[] = {
0199     { .name = "intel-int3496" },
0200     {},
0201 };
0202 MODULE_DEVICE_TABLE(platform, int3496_ids);
0203
0204 static struct platform_driver int3496_driver = {
0205     .driver = {
0206         .name = "intel-int3496",
0207         .acpi_match_table = int3496_acpi_match,
0208     },
0209     .probe = int3496_probe,
0210     .id_table = int3496_ids,
0211 };
0212
0213 module_platform_driver(int3496_driver);
0214
0215 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
0216 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
0217 MODULE_LICENSE("GPL v2");