1 /* 2 * Intel INT3496 ACPI device extcon driver 3 * 4 * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com> 5 * 6 * Based on android x86 kernel code which is: 7 * 8 * Copyright (c) 2014, Intel Corporation. 9 * Author: David Cohen <david.a.cohen@linux.intel.com> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License version 2 as 13 * published by the Free Software Foundation. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 */ 20 21 #include <linux/acpi.h> 22 #include <linux/extcon-provider.h> 23 #include <linux/gpio.h> 24 #include <linux/interrupt.h> 25 #include <linux/module.h> 26 #include <linux/platform_device.h> 27 28 #define INT3496_GPIO_USB_ID 0 29 #define INT3496_GPIO_VBUS_EN 1 30 #define INT3496_GPIO_USB_MUX 2 31 #define DEBOUNCE_TIME msecs_to_jiffies(50) 32 33 struct int3496_data { 34 struct device *dev; 35 struct extcon_dev *edev; 36 struct delayed_work work; 37 struct gpio_desc *gpio_usb_id; 38 struct gpio_desc *gpio_vbus_en; 39 struct gpio_desc *gpio_usb_mux; 40 int usb_id_irq; 41 }; 42 43 static const unsigned int int3496_cable[] = { 44 EXTCON_USB_HOST, 45 EXTCON_NONE, 46 }; 47 48 static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false }; 49 static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false }; 50 static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false }; 51 52 static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = { 53 { "id-gpios", &id_gpios, 1 }, 54 { "vbus-gpios", &vbus_gpios, 1 }, 55 { "mux-gpios", &mux_gpios, 1 }, 56 { }, 57 }; 58 59 static void int3496_do_usb_id(struct work_struct *work) 60 { 61 struct int3496_data *data = 62 container_of(work, struct int3496_data, work.work); 63 int id = gpiod_get_value_cansleep(data->gpio_usb_id); 64 65 /* id == 1: PERIPHERAL, id == 0: HOST */ 66 dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST"); 67 68 /* 69 * Peripheral: set USB mux to peripheral and disable VBUS 70 * Host: set USB mux to host and enable VBUS 71 */ 72 if (!IS_ERR(data->gpio_usb_mux)) 73 gpiod_direction_output(data->gpio_usb_mux, id); 74 75 if (!IS_ERR(data->gpio_vbus_en)) 76 gpiod_direction_output(data->gpio_vbus_en, !id); 77 78 extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id); 79 } 80 81 static irqreturn_t int3496_thread_isr(int irq, void *priv) 82 { 83 struct int3496_data *data = priv; 84 85 /* Let the pin settle before processing it */ 86 mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME); 87 88 return IRQ_HANDLED; 89 } 90 91 static int int3496_probe(struct platform_device *pdev) 92 { 93 struct device *dev = &pdev->dev; 94 struct int3496_data *data; 95 int ret; 96 97 ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios); 98 if (ret) { 99 dev_err(dev, "can't add GPIO ACPI mapping\n"); 100 return ret; 101 } 102 103 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 104 if (!data) 105 return -ENOMEM; 106 107 data->dev = dev; 108 INIT_DELAYED_WORK(&data->work, int3496_do_usb_id); 109 110 data->gpio_usb_id = devm_gpiod_get(dev, "id", GPIOD_IN); 111 if (IS_ERR(data->gpio_usb_id)) { 112 ret = PTR_ERR(data->gpio_usb_id); 113 dev_err(dev, "can't request USB ID GPIO: %d\n", ret); 114 return ret; 115 } else if (gpiod_get_direction(data->gpio_usb_id) != GPIOF_DIR_IN) { 116 dev_warn(dev, FW_BUG "USB ID GPIO not in input mode, fixing\n"); 117 gpiod_direction_input(data->gpio_usb_id); 118 } 119 120 data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id); 121 if (data->usb_id_irq < 0) { 122 dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq); 123 return data->usb_id_irq; 124 } 125 126 data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS); 127 if (IS_ERR(data->gpio_vbus_en)) 128 dev_info(dev, "can't request VBUS EN GPIO\n"); 129 130 data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS); 131 if (IS_ERR(data->gpio_usb_mux)) 132 dev_info(dev, "can't request USB MUX GPIO\n"); 133 134 /* register extcon device */ 135 data->edev = devm_extcon_dev_allocate(dev, int3496_cable); 136 if (IS_ERR(data->edev)) 137 return -ENOMEM; 138 139 ret = devm_extcon_dev_register(dev, data->edev); 140 if (ret < 0) { 141 dev_err(dev, "can't register extcon device: %d\n", ret); 142 return ret; 143 } 144 145 ret = devm_request_threaded_irq(dev, data->usb_id_irq, 146 NULL, int3496_thread_isr, 147 IRQF_SHARED | IRQF_ONESHOT | 148 IRQF_TRIGGER_RISING | 149 IRQF_TRIGGER_FALLING, 150 dev_name(dev), data); 151 if (ret < 0) { 152 dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret); 153 return ret; 154 } 155 156 /* queue initial processing of id-pin */ 157 queue_delayed_work(system_wq, &data->work, 0); 158 159 platform_set_drvdata(pdev, data); 160 161 return 0; 162 } 163 164 static int int3496_remove(struct platform_device *pdev) 165 { 166 struct int3496_data *data = platform_get_drvdata(pdev); 167 168 devm_free_irq(&pdev->dev, data->usb_id_irq, data); 169 cancel_delayed_work_sync(&data->work); 170 171 return 0; 172 } 173 174 static const struct acpi_device_id int3496_acpi_match[] = { 175 { "INT3496" }, 176 { } 177 }; 178 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match); 179 180 static struct platform_driver int3496_driver = { 181 .driver = { 182 .name = "intel-int3496", 183 .acpi_match_table = int3496_acpi_match, 184 }, 185 .probe = int3496_probe, 186 .remove = int3496_remove, 187 }; 188 189 module_platform_driver(int3496_driver); 190 191 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 192 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver"); 193 MODULE_LICENSE("GPL"); 194