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 /* 54 * Some platforms have a bug in ACPI GPIO description making IRQ 55 * GPIO to be output only. Ask the GPIO core to ignore this limit. 56 */ 57 { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION }, 58 { "vbus-gpios", &vbus_gpios, 1 }, 59 { "mux-gpios", &mux_gpios, 1 }, 60 { }, 61 }; 62 63 static void int3496_do_usb_id(struct work_struct *work) 64 { 65 struct int3496_data *data = 66 container_of(work, struct int3496_data, work.work); 67 int id = gpiod_get_value_cansleep(data->gpio_usb_id); 68 69 /* id == 1: PERIPHERAL, id == 0: HOST */ 70 dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST"); 71 72 /* 73 * Peripheral: set USB mux to peripheral and disable VBUS 74 * Host: set USB mux to host and enable VBUS 75 */ 76 if (!IS_ERR(data->gpio_usb_mux)) 77 gpiod_direction_output(data->gpio_usb_mux, id); 78 79 if (!IS_ERR(data->gpio_vbus_en)) 80 gpiod_direction_output(data->gpio_vbus_en, !id); 81 82 extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id); 83 } 84 85 static irqreturn_t int3496_thread_isr(int irq, void *priv) 86 { 87 struct int3496_data *data = priv; 88 89 /* Let the pin settle before processing it */ 90 mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME); 91 92 return IRQ_HANDLED; 93 } 94 95 static int int3496_probe(struct platform_device *pdev) 96 { 97 struct device *dev = &pdev->dev; 98 struct int3496_data *data; 99 int ret; 100 101 ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios); 102 if (ret) { 103 dev_err(dev, "can't add GPIO ACPI mapping\n"); 104 return ret; 105 } 106 107 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 108 if (!data) 109 return -ENOMEM; 110 111 data->dev = dev; 112 INIT_DELAYED_WORK(&data->work, int3496_do_usb_id); 113 114 data->gpio_usb_id = devm_gpiod_get(dev, "id", GPIOD_IN); 115 if (IS_ERR(data->gpio_usb_id)) { 116 ret = PTR_ERR(data->gpio_usb_id); 117 dev_err(dev, "can't request USB ID GPIO: %d\n", ret); 118 return ret; 119 } 120 121 data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id); 122 if (data->usb_id_irq < 0) { 123 dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq); 124 return data->usb_id_irq; 125 } 126 127 data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS); 128 if (IS_ERR(data->gpio_vbus_en)) 129 dev_info(dev, "can't request VBUS EN GPIO\n"); 130 131 data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS); 132 if (IS_ERR(data->gpio_usb_mux)) 133 dev_info(dev, "can't request USB MUX GPIO\n"); 134 135 /* register extcon device */ 136 data->edev = devm_extcon_dev_allocate(dev, int3496_cable); 137 if (IS_ERR(data->edev)) 138 return -ENOMEM; 139 140 ret = devm_extcon_dev_register(dev, data->edev); 141 if (ret < 0) { 142 dev_err(dev, "can't register extcon device: %d\n", ret); 143 return ret; 144 } 145 146 ret = devm_request_threaded_irq(dev, data->usb_id_irq, 147 NULL, int3496_thread_isr, 148 IRQF_SHARED | IRQF_ONESHOT | 149 IRQF_TRIGGER_RISING | 150 IRQF_TRIGGER_FALLING, 151 dev_name(dev), data); 152 if (ret < 0) { 153 dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret); 154 return ret; 155 } 156 157 /* process id-pin so that we start with the right status */ 158 queue_delayed_work(system_wq, &data->work, 0); 159 flush_delayed_work(&data->work); 160 161 platform_set_drvdata(pdev, data); 162 163 return 0; 164 } 165 166 static int int3496_remove(struct platform_device *pdev) 167 { 168 struct int3496_data *data = platform_get_drvdata(pdev); 169 170 devm_free_irq(&pdev->dev, data->usb_id_irq, data); 171 cancel_delayed_work_sync(&data->work); 172 173 return 0; 174 } 175 176 static const struct acpi_device_id int3496_acpi_match[] = { 177 { "INT3496" }, 178 { } 179 }; 180 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match); 181 182 static struct platform_driver int3496_driver = { 183 .driver = { 184 .name = "intel-int3496", 185 .acpi_match_table = int3496_acpi_match, 186 }, 187 .probe = int3496_probe, 188 .remove = int3496_remove, 189 }; 190 191 module_platform_driver(int3496_driver); 192 193 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 194 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver"); 195 MODULE_LICENSE("GPL"); 196