1 /** 2 * drd.c - DesignWare USB3 DRD Controller Dual-role support 3 * 4 * Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com 5 * 6 * Authors: Roger Quadros <rogerq@ti.com> 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 of 10 * the License as 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 * You should have received a copy of the GNU General Public License 18 * along with this program. If not, see <http://www.gnu.org/licenses/>. 19 */ 20 21 #include <linux/extcon.h> 22 23 #include "debug.h" 24 #include "core.h" 25 #include "gadget.h" 26 27 static void dwc3_drd_update(struct dwc3 *dwc) 28 { 29 int id; 30 31 id = extcon_get_state(dwc->edev, EXTCON_USB_HOST); 32 if (id < 0) 33 id = 0; 34 35 dwc3_set_mode(dwc, id ? 36 DWC3_GCTL_PRTCAP_HOST : 37 DWC3_GCTL_PRTCAP_DEVICE); 38 } 39 40 static int dwc3_drd_notifier(struct notifier_block *nb, 41 unsigned long event, void *ptr) 42 { 43 struct dwc3 *dwc = container_of(nb, struct dwc3, edev_nb); 44 45 dwc3_set_mode(dwc, event ? 46 DWC3_GCTL_PRTCAP_HOST : 47 DWC3_GCTL_PRTCAP_DEVICE); 48 49 return NOTIFY_DONE; 50 } 51 52 int dwc3_drd_init(struct dwc3 *dwc) 53 { 54 int ret; 55 56 if (dwc->dev->of_node) { 57 if (of_property_read_bool(dwc->dev->of_node, "extcon")) 58 dwc->edev = extcon_get_edev_by_phandle(dwc->dev, 0); 59 60 if (IS_ERR(dwc->edev)) 61 return PTR_ERR(dwc->edev); 62 63 dwc->edev_nb.notifier_call = dwc3_drd_notifier; 64 ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST, 65 &dwc->edev_nb); 66 if (ret < 0) { 67 dev_err(dwc->dev, "couldn't register cable notifier\n"); 68 return ret; 69 } 70 } 71 72 dwc3_drd_update(dwc); 73 74 return 0; 75 } 76 77 void dwc3_drd_exit(struct dwc3 *dwc) 78 { 79 extcon_unregister_notifier(dwc->edev, EXTCON_USB_HOST, 80 &dwc->edev_nb); 81 82 dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE); 83 flush_work(&dwc->drd_work); 84 dwc3_gadget_exit(dwc); 85 } 86