drivers/extcon/extcon-intel-int3496.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Intel INT3496 ACPI device extcon driver
   4  *
   5  * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
   6  *
   7  * Based on android x86 kernel code which is:
   8  *
   9  * Copyright (c) 2014, Intel Corporation.
  10  * Author: David Cohen <david.a.cohen@linux.intel.com>
  11  */
  12
  13 #include <linux/acpi.h>
  14 #include <linux/devm-helpers.h>
  15 #include <linux/extcon-provider.h>
  16 #include <linux/gpio/consumer.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/module.h>
  19 #include <linux/platform_device.h>
  20
  21 #define INT3496_GPIO_USB_ID     0
  22 #define INT3496_GPIO_VBUS_EN    1
  23 #define INT3496_GPIO_USB_MUX    2
  24 #define DEBOUNCE_TIME           msecs_to_jiffies(50)
  25
  26 struct int3496_data {
  27         struct device *dev;
  28         struct extcon_dev *edev;
  29         struct delayed_work work;
  30         struct gpio_desc *gpio_usb_id;
  31         struct gpio_desc *gpio_vbus_en;
  32         struct gpio_desc *gpio_usb_mux;
  33         int usb_id_irq;
  34 };
  35
  36 static const unsigned int int3496_cable[] = {
  37         EXTCON_USB_HOST,
  38         EXTCON_NONE,
  39 };
  40
  41 static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false };
  42 static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false };
  43 static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false };
  44
  45 static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = {
  46         /*
  47          * Some platforms have a bug in ACPI GPIO description making IRQ
  48          * GPIO to be output only. Ask the GPIO core to ignore this limit.
  49          */
  50         { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
  51         { "vbus-gpios", &vbus_gpios, 1 },
  52         { "mux-gpios", &mux_gpios, 1 },
  53         { },
  54 };
  55
  56 static void int3496_do_usb_id(struct work_struct *work)
  57 {
  58         struct int3496_data *data =
  59                 container_of(work, struct int3496_data, work.work);
  60         int id = gpiod_get_value_cansleep(data->gpio_usb_id);
  61
  62         /* id == 1: PERIPHERAL, id == 0: HOST */
  63         dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
  64
  65         /*
  66          * Peripheral: set USB mux to peripheral and disable VBUS
  67          * Host: set USB mux to host and enable VBUS
  68          */
  69         if (!IS_ERR(data->gpio_usb_mux))
  70                 gpiod_direction_output(data->gpio_usb_mux, id);
  71
  72         if (!IS_ERR(data->gpio_vbus_en))
  73                 gpiod_direction_output(data->gpio_vbus_en, !id);
  74
  75         extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
  76 }
  77
  78 static irqreturn_t int3496_thread_isr(int irq, void *priv)
  79 {
  80         struct int3496_data *data = priv;
  81
  82         /* Let the pin settle before processing it */
  83         mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
  84
  85         return IRQ_HANDLED;
  86 }
  87
  88 static int int3496_probe(struct platform_device *pdev)
  89 {
  90         struct device *dev = &pdev->dev;
  91         struct int3496_data *data;
  92         int ret;
  93
  94         ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios);
  95         if (ret) {
  96                 dev_err(dev, "can't add GPIO ACPI mapping\n");
  97                 return ret;
  98         }
  99
 100         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 101         if (!data)
 102                 return -ENOMEM;
 103
 104         data->dev = dev;
 105         ret = devm_delayed_work_autocancel(dev, &data->work, int3496_do_usb_id);
 106         if (ret)
 107                 return ret;
 108
 109         data->gpio_usb_id = devm_gpiod_get(dev, "id", GPIOD_IN);
 110         if (IS_ERR(data->gpio_usb_id)) {
 111                 ret = PTR_ERR(data->gpio_usb_id);
 112                 dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
 113                 return ret;
 114         }
 115
 116         data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
 117         if (data->usb_id_irq < 0) {
 118                 dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
 119                 return data->usb_id_irq;
 120         }
 121
 122         data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS);
 123         if (IS_ERR(data->gpio_vbus_en))
 124                 dev_info(dev, "can't request VBUS EN GPIO\n");
 125
 126         data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS);
 127         if (IS_ERR(data->gpio_usb_mux))
 128                 dev_info(dev, "can't request USB MUX GPIO\n");
 129
 130         /* register extcon device */
 131         data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
 132         if (IS_ERR(data->edev))
 133                 return -ENOMEM;
 134
 135         ret = devm_extcon_dev_register(dev, data->edev);
 136         if (ret < 0) {
 137                 dev_err(dev, "can't register extcon device: %d\n", ret);
 138                 return ret;
 139         }
 140
 141         ret = devm_request_threaded_irq(dev, data->usb_id_irq,
 142                                         NULL, int3496_thread_isr,
 143                                         IRQF_SHARED | IRQF_ONESHOT |
 144                                         IRQF_TRIGGER_RISING |
 145                                         IRQF_TRIGGER_FALLING,
 146                                         dev_name(dev), data);
 147         if (ret < 0) {
 148                 dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
 149                 return ret;
 150         }
 151
 152         /* process id-pin so that we start with the right status */
 153         queue_delayed_work(system_wq, &data->work, 0);
 154         flush_delayed_work(&data->work);
 155
 156         platform_set_drvdata(pdev, data);
 157
 158         return 0;
 159 }
 160
 161 static const struct acpi_device_id int3496_acpi_match[] = {
 162         { "INT3496" },
 163         { }
 164 };
 165 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
 166
 167 static struct platform_driver int3496_driver = {
 168         .driver = {
 169                 .name = "intel-int3496",
 170                 .acpi_match_table = int3496_acpi_match,
 171         },
 172         .probe = int3496_probe,
 173 };
 174
 175 module_platform_driver(int3496_driver);
 176
 177 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 178 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
 179 MODULE_LICENSE("GPL v2");