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/extcon-provider.h>
  15 #include <linux/gpio/consumer.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/module.h>
  18 #include <linux/platform_device.h>
  19
  20 #define INT3496_GPIO_USB_ID     0
  21 #define INT3496_GPIO_VBUS_EN    1
  22 #define INT3496_GPIO_USB_MUX    2
  23 #define DEBOUNCE_TIME           msecs_to_jiffies(50)
  24
  25 struct int3496_data {
  26         struct device *dev;
  27         struct extcon_dev *edev;
  28         struct delayed_work work;
  29         struct gpio_desc *gpio_usb_id;
  30         struct gpio_desc *gpio_vbus_en;
  31         struct gpio_desc *gpio_usb_mux;
  32         int usb_id_irq;
  33 };
  34
  35 static const unsigned int int3496_cable[] = {
  36         EXTCON_USB_HOST,
  37         EXTCON_NONE,
  38 };
  39
  40 static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false };
  41 static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false };
  42 static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false };
  43
  44 static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = {
  45         /*
  46          * Some platforms have a bug in ACPI GPIO description making IRQ
  47          * GPIO to be output only. Ask the GPIO core to ignore this limit.
  48          */
  49         { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
  50         { "vbus-gpios", &vbus_gpios, 1 },
  51         { "mux-gpios", &mux_gpios, 1 },
  52         { },
  53 };
  54
  55 static void int3496_do_usb_id(struct work_struct *work)
  56 {
  57         struct int3496_data *data =
  58                 container_of(work, struct int3496_data, work.work);
  59         int id = gpiod_get_value_cansleep(data->gpio_usb_id);
  60
  61         /* id == 1: PERIPHERAL, id == 0: HOST */
  62         dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
  63
  64         /*
  65          * Peripheral: set USB mux to peripheral and disable VBUS
  66          * Host: set USB mux to host and enable VBUS
  67          */
  68         if (!IS_ERR(data->gpio_usb_mux))
  69                 gpiod_direction_output(data->gpio_usb_mux, id);
  70
  71         if (!IS_ERR(data->gpio_vbus_en))
  72                 gpiod_direction_output(data->gpio_vbus_en, !id);
  73
  74         extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
  75 }
  76
  77 static irqreturn_t int3496_thread_isr(int irq, void *priv)
  78 {
  79         struct int3496_data *data = priv;
  80
  81         /* Let the pin settle before processing it */
  82         mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
  83
  84         return IRQ_HANDLED;
  85 }
  86
  87 static int int3496_probe(struct platform_device *pdev)
  88 {
  89         struct device *dev = &pdev->dev;
  90         struct int3496_data *data;
  91         int ret;
  92
  93         ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios);
  94         if (ret) {
  95                 dev_err(dev, "can't add GPIO ACPI mapping\n");
  96                 return ret;
  97         }
  98
  99         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 100         if (!data)
 101                 return -ENOMEM;
 102
 103         data->dev = dev;
 104         INIT_DELAYED_WORK(&data->work, int3496_do_usb_id);
 105
 106         data->gpio_usb_id = devm_gpiod_get(dev, "id", GPIOD_IN);
 107         if (IS_ERR(data->gpio_usb_id)) {
 108                 ret = PTR_ERR(data->gpio_usb_id);
 109                 dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
 110                 return ret;
 111         }
 112
 113         data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
 114         if (data->usb_id_irq < 0) {
 115                 dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
 116                 return data->usb_id_irq;
 117         }
 118
 119         data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS);
 120         if (IS_ERR(data->gpio_vbus_en))
 121                 dev_info(dev, "can't request VBUS EN GPIO\n");
 122
 123         data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS);
 124         if (IS_ERR(data->gpio_usb_mux))
 125                 dev_info(dev, "can't request USB MUX GPIO\n");
 126
 127         /* register extcon device */
 128         data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
 129         if (IS_ERR(data->edev))
 130                 return -ENOMEM;
 131
 132         ret = devm_extcon_dev_register(dev, data->edev);
 133         if (ret < 0) {
 134                 dev_err(dev, "can't register extcon device: %d\n", ret);
 135                 return ret;
 136         }
 137
 138         ret = devm_request_threaded_irq(dev, data->usb_id_irq,
 139                                         NULL, int3496_thread_isr,
 140                                         IRQF_SHARED | IRQF_ONESHOT |
 141                                         IRQF_TRIGGER_RISING |
 142                                         IRQF_TRIGGER_FALLING,
 143                                         dev_name(dev), data);
 144         if (ret < 0) {
 145                 dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
 146                 return ret;
 147         }
 148
 149         /* process id-pin so that we start with the right status */
 150         queue_delayed_work(system_wq, &data->work, 0);
 151         flush_delayed_work(&data->work);
 152
 153         platform_set_drvdata(pdev, data);
 154
 155         return 0;
 156 }
 157
 158 static int int3496_remove(struct platform_device *pdev)
 159 {
 160         struct int3496_data *data = platform_get_drvdata(pdev);
 161
 162         devm_free_irq(&pdev->dev, data->usb_id_irq, data);
 163         cancel_delayed_work_sync(&data->work);
 164
 165         return 0;
 166 }
 167
 168 static const struct acpi_device_id int3496_acpi_match[] = {
 169         { "INT3496" },
 170         { }
 171 };
 172 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
 173
 174 static struct platform_driver int3496_driver = {
 175         .driver = {
 176                 .name = "intel-int3496",
 177                 .acpi_match_table = int3496_acpi_match,
 178         },
 179         .probe = int3496_probe,
 180         .remove = int3496_remove,
 181 };
 182
 183 module_platform_driver(int3496_driver);
 184
 185 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 186 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
 187 MODULE_LICENSE("GPL v2");