Stephen Boyd | 38085c9 | 2016-09-09 14:48:47 -0700 | [diff] [blame] | 1 | /** |
| 2 | * extcon-qcom-spmi-misc.c - Qualcomm USB extcon driver to support USB ID |
| 3 | * detection based on extcon-usb-gpio.c. |
| 4 | * |
| 5 | * Copyright (C) 2016 Linaro, Ltd. |
| 6 | * Stephen Boyd <stephen.boyd@linaro.org> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License version 2 as |
| 10 | * published by the Free Software Foundation. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | */ |
| 17 | |
| 18 | #include <linux/extcon.h> |
| 19 | #include <linux/init.h> |
| 20 | #include <linux/interrupt.h> |
| 21 | #include <linux/kernel.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/platform_device.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <linux/workqueue.h> |
| 26 | |
| 27 | #define USB_ID_DEBOUNCE_MS 5 /* ms */ |
| 28 | |
| 29 | struct qcom_usb_extcon_info { |
| 30 | struct extcon_dev *edev; |
| 31 | int irq; |
| 32 | struct delayed_work wq_detcable; |
| 33 | unsigned long debounce_jiffies; |
| 34 | }; |
| 35 | |
| 36 | static const unsigned int qcom_usb_extcon_cable[] = { |
| 37 | EXTCON_USB_HOST, |
| 38 | EXTCON_NONE, |
| 39 | }; |
| 40 | |
| 41 | static void qcom_usb_extcon_detect_cable(struct work_struct *work) |
| 42 | { |
| 43 | bool id; |
| 44 | int ret; |
| 45 | struct qcom_usb_extcon_info *info = container_of(to_delayed_work(work), |
| 46 | struct qcom_usb_extcon_info, |
| 47 | wq_detcable); |
| 48 | |
| 49 | /* check ID and update cable state */ |
| 50 | ret = irq_get_irqchip_state(info->irq, IRQCHIP_STATE_LINE_LEVEL, &id); |
| 51 | if (ret) |
| 52 | return; |
| 53 | |
Stephen Boyd | 2925d36 | 2016-10-17 17:16:02 -0700 | [diff] [blame] | 54 | extcon_set_state_sync(info->edev, EXTCON_USB_HOST, !id); |
Stephen Boyd | 38085c9 | 2016-09-09 14:48:47 -0700 | [diff] [blame] | 55 | } |
| 56 | |
| 57 | static irqreturn_t qcom_usb_irq_handler(int irq, void *dev_id) |
| 58 | { |
| 59 | struct qcom_usb_extcon_info *info = dev_id; |
| 60 | |
| 61 | queue_delayed_work(system_power_efficient_wq, &info->wq_detcable, |
| 62 | info->debounce_jiffies); |
| 63 | |
| 64 | return IRQ_HANDLED; |
| 65 | } |
| 66 | |
| 67 | static int qcom_usb_extcon_probe(struct platform_device *pdev) |
| 68 | { |
| 69 | struct device *dev = &pdev->dev; |
| 70 | struct qcom_usb_extcon_info *info; |
| 71 | int ret; |
| 72 | |
| 73 | info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); |
| 74 | if (!info) |
| 75 | return -ENOMEM; |
| 76 | |
| 77 | info->edev = devm_extcon_dev_allocate(dev, qcom_usb_extcon_cable); |
| 78 | if (IS_ERR(info->edev)) { |
| 79 | dev_err(dev, "failed to allocate extcon device\n"); |
| 80 | return -ENOMEM; |
| 81 | } |
| 82 | |
| 83 | ret = devm_extcon_dev_register(dev, info->edev); |
| 84 | if (ret < 0) { |
| 85 | dev_err(dev, "failed to register extcon device\n"); |
| 86 | return ret; |
| 87 | } |
| 88 | |
| 89 | info->debounce_jiffies = msecs_to_jiffies(USB_ID_DEBOUNCE_MS); |
| 90 | INIT_DELAYED_WORK(&info->wq_detcable, qcom_usb_extcon_detect_cable); |
| 91 | |
| 92 | info->irq = platform_get_irq_byname(pdev, "usb_id"); |
| 93 | if (info->irq < 0) |
| 94 | return info->irq; |
| 95 | |
| 96 | ret = devm_request_threaded_irq(dev, info->irq, NULL, |
| 97 | qcom_usb_irq_handler, |
| 98 | IRQF_TRIGGER_RISING | |
| 99 | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, |
| 100 | pdev->name, info); |
| 101 | if (ret < 0) { |
| 102 | dev_err(dev, "failed to request handler for ID IRQ\n"); |
| 103 | return ret; |
| 104 | } |
| 105 | |
| 106 | platform_set_drvdata(pdev, info); |
| 107 | device_init_wakeup(dev, 1); |
| 108 | |
| 109 | /* Perform initial detection */ |
| 110 | qcom_usb_extcon_detect_cable(&info->wq_detcable.work); |
| 111 | |
| 112 | return 0; |
| 113 | } |
| 114 | |
| 115 | static int qcom_usb_extcon_remove(struct platform_device *pdev) |
| 116 | { |
| 117 | struct qcom_usb_extcon_info *info = platform_get_drvdata(pdev); |
| 118 | |
| 119 | cancel_delayed_work_sync(&info->wq_detcable); |
| 120 | |
| 121 | return 0; |
| 122 | } |
| 123 | |
| 124 | #ifdef CONFIG_PM_SLEEP |
| 125 | static int qcom_usb_extcon_suspend(struct device *dev) |
| 126 | { |
| 127 | struct qcom_usb_extcon_info *info = dev_get_drvdata(dev); |
| 128 | int ret = 0; |
| 129 | |
| 130 | if (device_may_wakeup(dev)) |
| 131 | ret = enable_irq_wake(info->irq); |
| 132 | |
| 133 | return ret; |
| 134 | } |
| 135 | |
| 136 | static int qcom_usb_extcon_resume(struct device *dev) |
| 137 | { |
| 138 | struct qcom_usb_extcon_info *info = dev_get_drvdata(dev); |
| 139 | int ret = 0; |
| 140 | |
| 141 | if (device_may_wakeup(dev)) |
| 142 | ret = disable_irq_wake(info->irq); |
| 143 | |
| 144 | return ret; |
| 145 | } |
| 146 | #endif |
| 147 | |
| 148 | static SIMPLE_DEV_PM_OPS(qcom_usb_extcon_pm_ops, |
| 149 | qcom_usb_extcon_suspend, qcom_usb_extcon_resume); |
| 150 | |
| 151 | static const struct of_device_id qcom_usb_extcon_dt_match[] = { |
| 152 | { .compatible = "qcom,pm8941-misc", }, |
| 153 | { } |
| 154 | }; |
| 155 | MODULE_DEVICE_TABLE(of, qcom_usb_extcon_dt_match); |
| 156 | |
| 157 | static struct platform_driver qcom_usb_extcon_driver = { |
| 158 | .probe = qcom_usb_extcon_probe, |
| 159 | .remove = qcom_usb_extcon_remove, |
| 160 | .driver = { |
| 161 | .name = "extcon-pm8941-misc", |
| 162 | .pm = &qcom_usb_extcon_pm_ops, |
| 163 | .of_match_table = qcom_usb_extcon_dt_match, |
| 164 | }, |
| 165 | }; |
| 166 | module_platform_driver(qcom_usb_extcon_driver); |
| 167 | |
| 168 | MODULE_DESCRIPTION("QCOM USB ID extcon driver"); |
| 169 | MODULE_AUTHOR("Stephen Boyd <stephen.boyd@linaro.org>"); |
| 170 | MODULE_LICENSE("GPL v2"); |