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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Maxim Integrated MAX3355 USB OTG chip extcon driver4 *5 * Copyright (C) 2014-2015 Cogent Embedded, Inc.6 * Author: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>7 */8 9#include <linux/extcon-provider.h>10#include <linux/gpio/consumer.h>11#include <linux/interrupt.h>12#include <linux/module.h>13#include <linux/mod_devicetable.h>14#include <linux/platform_device.h>15 16struct max3355_data {17 struct extcon_dev *edev;18 struct gpio_desc *id_gpiod;19 struct gpio_desc *shdn_gpiod;20};21 22static const unsigned int max3355_cable[] = {23 EXTCON_USB,24 EXTCON_USB_HOST,25 EXTCON_NONE,26};27 28static irqreturn_t max3355_id_irq(int irq, void *dev_id)29{30 struct max3355_data *data = dev_id;31 int id = gpiod_get_value_cansleep(data->id_gpiod);32 33 if (id) {34 /*35 * ID = 1 means USB HOST cable detached.36 * As we don't have event for USB peripheral cable attached,37 * we simulate USB peripheral attach here.38 */39 extcon_set_state_sync(data->edev, EXTCON_USB_HOST, false);40 extcon_set_state_sync(data->edev, EXTCON_USB, true);41 } else {42 /*43 * ID = 0 means USB HOST cable attached.44 * As we don't have event for USB peripheral cable detached,45 * we simulate USB peripheral detach here.46 */47 extcon_set_state_sync(data->edev, EXTCON_USB, false);48 extcon_set_state_sync(data->edev, EXTCON_USB_HOST, true);49 }50 51 return IRQ_HANDLED;52}53 54static int max3355_probe(struct platform_device *pdev)55{56 struct max3355_data *data;57 struct gpio_desc *gpiod;58 int irq, err;59 60 data = devm_kzalloc(&pdev->dev, sizeof(struct max3355_data),61 GFP_KERNEL);62 if (!data)63 return -ENOMEM;64 65 gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);66 if (IS_ERR(gpiod)) {67 dev_err(&pdev->dev, "failed to get ID_OUT GPIO\n");68 return PTR_ERR(gpiod);69 }70 data->id_gpiod = gpiod;71 72 gpiod = devm_gpiod_get(&pdev->dev, "maxim,shdn", GPIOD_OUT_HIGH);73 if (IS_ERR(gpiod)) {74 dev_err(&pdev->dev, "failed to get SHDN# GPIO\n");75 return PTR_ERR(gpiod);76 }77 data->shdn_gpiod = gpiod;78 79 data->edev = devm_extcon_dev_allocate(&pdev->dev, max3355_cable);80 if (IS_ERR(data->edev)) {81 dev_err(&pdev->dev, "failed to allocate extcon device\n");82 return PTR_ERR(data->edev);83 }84 85 err = devm_extcon_dev_register(&pdev->dev, data->edev);86 if (err < 0) {87 dev_err(&pdev->dev, "failed to register extcon device\n");88 return err;89 }90 91 irq = gpiod_to_irq(data->id_gpiod);92 if (irq < 0) {93 dev_err(&pdev->dev, "failed to translate ID_OUT GPIO to IRQ\n");94 return irq;95 }96 97 err = devm_request_threaded_irq(&pdev->dev, irq, NULL, max3355_id_irq,98 IRQF_ONESHOT | IRQF_NO_SUSPEND |99 IRQF_TRIGGER_RISING |100 IRQF_TRIGGER_FALLING,101 pdev->name, data);102 if (err < 0) {103 dev_err(&pdev->dev, "failed to request ID_OUT IRQ\n");104 return err;105 }106 107 platform_set_drvdata(pdev, data);108 109 /* Perform initial detection */110 max3355_id_irq(irq, data);111 112 return 0;113}114 115static void max3355_remove(struct platform_device *pdev)116{117 struct max3355_data *data = platform_get_drvdata(pdev);118 119 gpiod_set_value_cansleep(data->shdn_gpiod, 0);120}121 122static const struct of_device_id max3355_match_table[] = {123 { .compatible = "maxim,max3355", },124 { }125};126MODULE_DEVICE_TABLE(of, max3355_match_table);127 128static struct platform_driver max3355_driver = {129 .probe = max3355_probe,130 .remove_new = max3355_remove,131 .driver = {132 .name = "extcon-max3355",133 .of_match_table = max3355_match_table,134 },135};136 137module_platform_driver(max3355_driver);138 139MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");140MODULE_DESCRIPTION("Maxim MAX3355 extcon driver");141MODULE_LICENSE("GPL v2");142