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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * drivers/extcon/extcon-usb-gpio.c - USB GPIO extcon driver4 *5 * Copyright (C) 2015 Texas Instruments Incorporated - https://www.ti.com6 * Author: Roger Quadros <rogerq@ti.com>7 */8 9#include <linux/extcon-provider.h>10#include <linux/gpio/consumer.h>11#include <linux/init.h>12#include <linux/interrupt.h>13#include <linux/irq.h>14#include <linux/kernel.h>15#include <linux/module.h>16#include <linux/platform_device.h>17#include <linux/slab.h>18#include <linux/workqueue.h>19#include <linux/pinctrl/consumer.h>20#include <linux/mod_devicetable.h>21 22#define USB_GPIO_DEBOUNCE_MS 20 /* ms */23 24struct usb_extcon_info {25 struct device *dev;26 struct extcon_dev *edev;27 28 struct gpio_desc *id_gpiod;29 struct gpio_desc *vbus_gpiod;30 int id_irq;31 int vbus_irq;32 33 unsigned long debounce_jiffies;34 struct delayed_work wq_detcable;35};36 37static const unsigned int usb_extcon_cable[] = {38 EXTCON_USB,39 EXTCON_USB_HOST,40 EXTCON_NONE,41};42 43/*44 * "USB" = VBUS and "USB-HOST" = !ID, so we have:45 * Both "USB" and "USB-HOST" can't be set as active at the46 * same time so if "USB-HOST" is active (i.e. ID is 0) we keep "USB" inactive47 * even if VBUS is on.48 *49 * State | ID | VBUS50 * ----------------------------------------51 * [1] USB | H | H52 * [2] none | H | L53 * [3] USB-HOST | L | H54 * [4] USB-HOST | L | L55 *56 * In case we have only one of these signals:57 * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1.58 * - ID only - we want to distinguish between [1] and [4], so VBUS = ID.59*/60static void usb_extcon_detect_cable(struct work_struct *work)61{62 int id, vbus;63 struct usb_extcon_info *info = container_of(to_delayed_work(work),64 struct usb_extcon_info,65 wq_detcable);66 67 /* check ID and VBUS and update cable state */68 id = info->id_gpiod ?69 gpiod_get_value_cansleep(info->id_gpiod) : 1;70 vbus = info->vbus_gpiod ?71 gpiod_get_value_cansleep(info->vbus_gpiod) : id;72 73 /* at first we clean states which are no longer active */74 if (id)75 extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);76 if (!vbus)77 extcon_set_state_sync(info->edev, EXTCON_USB, false);78 79 if (!id) {80 extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);81 } else {82 if (vbus)83 extcon_set_state_sync(info->edev, EXTCON_USB, true);84 }85}86 87static irqreturn_t usb_irq_handler(int irq, void *dev_id)88{89 struct usb_extcon_info *info = dev_id;90 91 queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,92 info->debounce_jiffies);93 94 return IRQ_HANDLED;95}96 97static int usb_extcon_probe(struct platform_device *pdev)98{99 struct device *dev = &pdev->dev;100 struct device_node *np = dev->of_node;101 struct usb_extcon_info *info;102 int ret;103 104 if (!np)105 return -EINVAL;106 107 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);108 if (!info)109 return -ENOMEM;110 111 info->dev = dev;112 info->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id", GPIOD_IN);113 info->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",114 GPIOD_IN);115 116 if (!info->id_gpiod && !info->vbus_gpiod) {117 dev_err(dev, "failed to get gpios\n");118 return -ENODEV;119 }120 121 if (IS_ERR(info->id_gpiod))122 return PTR_ERR(info->id_gpiod);123 124 if (IS_ERR(info->vbus_gpiod))125 return PTR_ERR(info->vbus_gpiod);126 127 info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);128 if (IS_ERR(info->edev)) {129 dev_err(dev, "failed to allocate extcon device\n");130 return -ENOMEM;131 }132 133 ret = devm_extcon_dev_register(dev, info->edev);134 if (ret < 0) {135 dev_err(dev, "failed to register extcon device\n");136 return ret;137 }138 139 if (info->id_gpiod)140 ret = gpiod_set_debounce(info->id_gpiod,141 USB_GPIO_DEBOUNCE_MS * 1000);142 if (!ret && info->vbus_gpiod)143 ret = gpiod_set_debounce(info->vbus_gpiod,144 USB_GPIO_DEBOUNCE_MS * 1000);145 146 if (ret < 0)147 info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS);148 149 INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable);150 151 if (info->id_gpiod) {152 info->id_irq = gpiod_to_irq(info->id_gpiod);153 if (info->id_irq < 0) {154 dev_err(dev, "failed to get ID IRQ\n");155 return info->id_irq;156 }157 158 ret = devm_request_threaded_irq(dev, info->id_irq, NULL,159 usb_irq_handler,160 IRQF_TRIGGER_RISING |161 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,162 pdev->name, info);163 if (ret < 0) {164 dev_err(dev, "failed to request handler for ID IRQ\n");165 return ret;166 }167 }168 169 if (info->vbus_gpiod) {170 info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);171 if (info->vbus_irq < 0) {172 dev_err(dev, "failed to get VBUS IRQ\n");173 return info->vbus_irq;174 }175 176 ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,177 usb_irq_handler,178 IRQF_TRIGGER_RISING |179 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,180 pdev->name, info);181 if (ret < 0) {182 dev_err(dev, "failed to request handler for VBUS IRQ\n");183 return ret;184 }185 }186 187 platform_set_drvdata(pdev, info);188 device_set_wakeup_capable(&pdev->dev, true);189 190 /* Perform initial detection */191 usb_extcon_detect_cable(&info->wq_detcable.work);192 193 return 0;194}195 196static void usb_extcon_remove(struct platform_device *pdev)197{198 struct usb_extcon_info *info = platform_get_drvdata(pdev);199 200 cancel_delayed_work_sync(&info->wq_detcable);201 device_init_wakeup(&pdev->dev, false);202}203 204#ifdef CONFIG_PM_SLEEP205static int usb_extcon_suspend(struct device *dev)206{207 struct usb_extcon_info *info = dev_get_drvdata(dev);208 int ret = 0;209 210 if (device_may_wakeup(dev)) {211 if (info->id_gpiod) {212 ret = enable_irq_wake(info->id_irq);213 if (ret)214 return ret;215 }216 if (info->vbus_gpiod) {217 ret = enable_irq_wake(info->vbus_irq);218 if (ret) {219 if (info->id_gpiod)220 disable_irq_wake(info->id_irq);221 222 return ret;223 }224 }225 }226 227 if (!device_may_wakeup(dev))228 pinctrl_pm_select_sleep_state(dev);229 230 return ret;231}232 233static int usb_extcon_resume(struct device *dev)234{235 struct usb_extcon_info *info = dev_get_drvdata(dev);236 int ret = 0;237 238 if (!device_may_wakeup(dev))239 pinctrl_pm_select_default_state(dev);240 241 if (device_may_wakeup(dev)) {242 if (info->id_gpiod) {243 ret = disable_irq_wake(info->id_irq);244 if (ret)245 return ret;246 }247 if (info->vbus_gpiod) {248 ret = disable_irq_wake(info->vbus_irq);249 if (ret) {250 if (info->id_gpiod)251 enable_irq_wake(info->id_irq);252 253 return ret;254 }255 }256 }257 258 queue_delayed_work(system_power_efficient_wq,259 &info->wq_detcable, 0);260 261 return ret;262}263#endif264 265static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops,266 usb_extcon_suspend, usb_extcon_resume);267 268static const struct of_device_id usb_extcon_dt_match[] = {269 { .compatible = "linux,extcon-usb-gpio", },270 { /* sentinel */ }271};272MODULE_DEVICE_TABLE(of, usb_extcon_dt_match);273 274static const struct platform_device_id usb_extcon_platform_ids[] = {275 { .name = "extcon-usb-gpio", },276 { /* sentinel */ }277};278MODULE_DEVICE_TABLE(platform, usb_extcon_platform_ids);279 280static struct platform_driver usb_extcon_driver = {281 .probe = usb_extcon_probe,282 .remove_new = usb_extcon_remove,283 .driver = {284 .name = "extcon-usb-gpio",285 .pm = &usb_extcon_pm_ops,286 .of_match_table = usb_extcon_dt_match,287 },288 .id_table = usb_extcon_platform_ids,289};290 291module_platform_driver(usb_extcon_driver);292 293MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");294MODULE_DESCRIPTION("USB GPIO extcon driver");295MODULE_LICENSE("GPL v2");296