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 #include <linux/regulator/consumer.h>
  21
  22 #define INT3496_GPIO_USB_ID     0
  23 #define INT3496_GPIO_VBUS_EN    1
  24 #define INT3496_GPIO_USB_MUX    2
  25 #define DEBOUNCE_TIME           msecs_to_jiffies(50)
  26
  27 struct int3496_data {
  28         struct device *dev;
  29         struct extcon_dev *edev;
  30         struct delayed_work work;
  31         struct gpio_desc *gpio_usb_id;
  32         struct gpio_desc *gpio_vbus_en;
  33         struct gpio_desc *gpio_usb_mux;
  34         struct regulator *vbus_boost;
  35         int usb_id_irq;
  36         bool vbus_boost_enabled;
  37 };
  38
  39 static const unsigned int int3496_cable[] = {
  40         EXTCON_USB_HOST,
  41         EXTCON_NONE,
  42 };
  43
  44 static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false };
  45 static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false };
  46 static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false };
  47
  48 static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = {
  49         /*
  50          * Some platforms have a bug in ACPI GPIO description making IRQ
  51          * GPIO to be output only. Ask the GPIO core to ignore this limit.
  52          */
  53         { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
  54         { "vbus-gpios", &vbus_gpios, 1 },
  55         { "mux-gpios", &mux_gpios, 1 },
  56         { },
  57 };
  58
  59 static void int3496_set_vbus_boost(struct int3496_data *data, bool enable)
  60 {
  61         int ret;
  62
  63         if (IS_ERR_OR_NULL(data->vbus_boost))
  64                 return;
  65
  66         if (data->vbus_boost_enabled == enable)
  67                 return;
  68
  69         if (enable)
  70                 ret = regulator_enable(data->vbus_boost);
  71         else
  72                 ret = regulator_disable(data->vbus_boost);
  73
  74         if (ret == 0)
  75                 data->vbus_boost_enabled = enable;
  76         else
  77                 dev_err(data->dev, "Error updating Vbus boost regulator: %d\n", ret);
  78 }
  79
  80 static void int3496_do_usb_id(struct work_struct *work)
  81 {
  82         struct int3496_data *data =
  83                 container_of(work, struct int3496_data, work.work);
  84         int id = gpiod_get_value_cansleep(data->gpio_usb_id);
  85
  86         /* id == 1: PERIPHERAL, id == 0: HOST */
  87         dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
  88
  89         /*
  90          * Peripheral: set USB mux to peripheral and disable VBUS
  91          * Host: set USB mux to host and enable VBUS
  92          */
  93         if (!IS_ERR(data->gpio_usb_mux))
  94                 gpiod_direction_output(data->gpio_usb_mux, id);
  95
  96         if (!IS_ERR(data->gpio_vbus_en))
  97                 gpiod_direction_output(data->gpio_vbus_en, !id);
  98         else
  99                 int3496_set_vbus_boost(data, !id);
 100
 101         extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
 102 }
 103
 104 static irqreturn_t int3496_thread_isr(int irq, void *priv)
 105 {
 106         struct int3496_data *data = priv;
 107
 108         /* Let the pin settle before processing it */
 109         mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
 110
 111         return IRQ_HANDLED;
 112 }
 113
 114 static int int3496_probe(struct platform_device *pdev)
 115 {
 116         struct device *dev = &pdev->dev;
 117         struct int3496_data *data;
 118         int ret;
 119
 120         if (has_acpi_companion(dev)) {
 121                 ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios);
 122                 if (ret) {
 123                         dev_err(dev, "can't add GPIO ACPI mapping\n");
 124                         return ret;
 125                 }
 126         }
 127
 128         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 129         if (!data)
 130                 return -ENOMEM;
 131
 132         data->dev = dev;
 133         ret = devm_delayed_work_autocancel(dev, &data->work, int3496_do_usb_id);
 134         if (ret)
 135                 return ret;
 136
 137         data->gpio_usb_id =
 138                 devm_gpiod_get(dev, "id", GPIOD_IN | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
 139         if (IS_ERR(data->gpio_usb_id)) {
 140                 ret = PTR_ERR(data->gpio_usb_id);
 141                 dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
 142                 return ret;
 143         }
 144
 145         data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
 146         if (data->usb_id_irq < 0) {
 147                 dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
 148                 return data->usb_id_irq;
 149         }
 150
 151         data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS);
 152         if (IS_ERR(data->gpio_vbus_en)) {
 153                 dev_dbg(dev, "can't request VBUS EN GPIO\n");
 154                 data->vbus_boost = devm_regulator_get_optional(dev, "vbus");
 155         }
 156
 157         data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS);
 158         if (IS_ERR(data->gpio_usb_mux))
 159                 dev_dbg(dev, "can't request USB MUX GPIO\n");
 160
 161         /* register extcon device */
 162         data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
 163         if (IS_ERR(data->edev))
 164                 return -ENOMEM;
 165
 166         ret = devm_extcon_dev_register(dev, data->edev);
 167         if (ret < 0) {
 168                 dev_err(dev, "can't register extcon device: %d\n", ret);
 169                 return ret;
 170         }
 171
 172         ret = devm_request_threaded_irq(dev, data->usb_id_irq,
 173                                         NULL, int3496_thread_isr,
 174                                         IRQF_SHARED | IRQF_ONESHOT |
 175                                         IRQF_TRIGGER_RISING |
 176                                         IRQF_TRIGGER_FALLING,
 177                                         dev_name(dev), data);
 178         if (ret < 0) {
 179                 dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
 180                 return ret;
 181         }
 182
 183         /* process id-pin so that we start with the right status */
 184         queue_delayed_work(system_wq, &data->work, 0);
 185         flush_delayed_work(&data->work);
 186
 187         platform_set_drvdata(pdev, data);
 188
 189         return 0;
 190 }
 191
 192 static const struct acpi_device_id int3496_acpi_match[] = {
 193         { "INT3496" },
 194         { }
 195 };
 196 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
 197
 198 static const struct platform_device_id int3496_ids[] = {
 199         { .name = "intel-int3496" },
 200         {},
 201 };
 202 MODULE_DEVICE_TABLE(platform, int3496_ids);
 203
 204 static struct platform_driver int3496_driver = {
 205         .driver = {
 206                 .name = "intel-int3496",
 207                 .acpi_match_table = int3496_acpi_match,
 208         },
 209         .probe = int3496_probe,
 210         .id_table = int3496_ids,
 211 };
 212
 213 module_platform_driver(int3496_driver);
 214
 215 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 216 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
 217 MODULE_LICENSE("GPL v2");