1 // SPDX-License-Identifier: GPL-2.0-only 2 /** 3 * extcon-qcom-spmi-misc.c - Qualcomm USB extcon driver to support USB ID 4 * detection based on extcon-usb-gpio.c. 5 * 6 * Copyright (C) 2016 Linaro, Ltd. 7 * Stephen Boyd <stephen.boyd@linaro.org> 8 */ 9 10 #include <linux/extcon-provider.h> 11 #include <linux/init.h> 12 #include <linux/interrupt.h> 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 #include <linux/mod_devicetable.h> 16 #include <linux/platform_device.h> 17 #include <linux/slab.h> 18 #include <linux/workqueue.h> 19 20 #define USB_ID_DEBOUNCE_MS 5 /* ms */ 21 22 struct qcom_usb_extcon_info { 23 struct extcon_dev *edev; 24 int irq; 25 struct delayed_work wq_detcable; 26 unsigned long debounce_jiffies; 27 }; 28 29 static const unsigned int qcom_usb_extcon_cable[] = { 30 EXTCON_USB_HOST, 31 EXTCON_NONE, 32 }; 33 34 static void qcom_usb_extcon_detect_cable(struct work_struct *work) 35 { 36 bool id; 37 int ret; 38 struct qcom_usb_extcon_info *info = container_of(to_delayed_work(work), 39 struct qcom_usb_extcon_info, 40 wq_detcable); 41 42 /* check ID and update cable state */ 43 ret = irq_get_irqchip_state(info->irq, IRQCHIP_STATE_LINE_LEVEL, &id); 44 if (ret) 45 return; 46 47 extcon_set_state_sync(info->edev, EXTCON_USB_HOST, !id); 48 } 49 50 static irqreturn_t qcom_usb_irq_handler(int irq, void *dev_id) 51 { 52 struct qcom_usb_extcon_info *info = dev_id; 53 54 queue_delayed_work(system_power_efficient_wq, &info->wq_detcable, 55 info->debounce_jiffies); 56 57 return IRQ_HANDLED; 58 } 59 60 static int qcom_usb_extcon_probe(struct platform_device *pdev) 61 { 62 struct device *dev = &pdev->dev; 63 struct qcom_usb_extcon_info *info; 64 int ret; 65 66 info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); 67 if (!info) 68 return -ENOMEM; 69 70 info->edev = devm_extcon_dev_allocate(dev, qcom_usb_extcon_cable); 71 if (IS_ERR(info->edev)) { 72 dev_err(dev, "failed to allocate extcon device\n"); 73 return -ENOMEM; 74 } 75 76 ret = devm_extcon_dev_register(dev, info->edev); 77 if (ret < 0) { 78 dev_err(dev, "failed to register extcon device\n"); 79 return ret; 80 } 81 82 info->debounce_jiffies = msecs_to_jiffies(USB_ID_DEBOUNCE_MS); 83 INIT_DELAYED_WORK(&info->wq_detcable, qcom_usb_extcon_detect_cable); 84 85 info->irq = platform_get_irq_byname(pdev, "usb_id"); 86 if (info->irq < 0) 87 return info->irq; 88 89 ret = devm_request_threaded_irq(dev, info->irq, NULL, 90 qcom_usb_irq_handler, 91 IRQF_TRIGGER_RISING | 92 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 93 pdev->name, info); 94 if (ret < 0) { 95 dev_err(dev, "failed to request handler for ID IRQ\n"); 96 return ret; 97 } 98 99 platform_set_drvdata(pdev, info); 100 device_init_wakeup(dev, 1); 101 102 /* Perform initial detection */ 103 qcom_usb_extcon_detect_cable(&info->wq_detcable.work); 104 105 return 0; 106 } 107 108 static int qcom_usb_extcon_remove(struct platform_device *pdev) 109 { 110 struct qcom_usb_extcon_info *info = platform_get_drvdata(pdev); 111 112 cancel_delayed_work_sync(&info->wq_detcable); 113 114 return 0; 115 } 116 117 #ifdef CONFIG_PM_SLEEP 118 static int qcom_usb_extcon_suspend(struct device *dev) 119 { 120 struct qcom_usb_extcon_info *info = dev_get_drvdata(dev); 121 int ret = 0; 122 123 if (device_may_wakeup(dev)) 124 ret = enable_irq_wake(info->irq); 125 126 return ret; 127 } 128 129 static int qcom_usb_extcon_resume(struct device *dev) 130 { 131 struct qcom_usb_extcon_info *info = dev_get_drvdata(dev); 132 int ret = 0; 133 134 if (device_may_wakeup(dev)) 135 ret = disable_irq_wake(info->irq); 136 137 return ret; 138 } 139 #endif 140 141 static SIMPLE_DEV_PM_OPS(qcom_usb_extcon_pm_ops, 142 qcom_usb_extcon_suspend, qcom_usb_extcon_resume); 143 144 static const struct of_device_id qcom_usb_extcon_dt_match[] = { 145 { .compatible = "qcom,pm8941-misc", }, 146 { } 147 }; 148 MODULE_DEVICE_TABLE(of, qcom_usb_extcon_dt_match); 149 150 static struct platform_driver qcom_usb_extcon_driver = { 151 .probe = qcom_usb_extcon_probe, 152 .remove = qcom_usb_extcon_remove, 153 .driver = { 154 .name = "extcon-pm8941-misc", 155 .pm = &qcom_usb_extcon_pm_ops, 156 .of_match_table = qcom_usb_extcon_dt_match, 157 }, 158 }; 159 module_platform_driver(qcom_usb_extcon_driver); 160 161 MODULE_DESCRIPTION("QCOM USB ID extcon driver"); 162 MODULE_AUTHOR("Stephen Boyd <stephen.boyd@linaro.org>"); 163 MODULE_LICENSE("GPL v2"); 164