1/* 2 * drivers/usb/otg/nop-usb-xceiv.c 3 * 4 * NOP USB transceiver for all USB transceiver which are either built-in 5 * into USB IP or which are mostly autonomous. 6 * 7 * Copyright (C) 2009 Texas Instruments Inc 8 * Author: Ajay Kumar Gupta <ajay.gupta@ti.com> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 23 * 24 * Current status: 25 * This provides a "nop" transceiver for PHYs which are 26 * autonomous such as isp1504, isp1707, etc. 27 */ 28 29#include <linux/module.h> 30#include <linux/platform_device.h> 31#include <linux/dma-mapping.h> 32#include <linux/usb/otg.h> 33#include <linux/slab.h> 34 35struct nop_usb_xceiv { 36 struct usb_phy phy; 37 struct device *dev; 38}; 39 40static struct platform_device *pd; 41 42void usb_nop_xceiv_register(void) 43{ 44 if (pd) 45 return; 46 pd = platform_device_register_simple("nop_usb_xceiv", -1, NULL, 0); 47 if (!pd) { 48 printk(KERN_ERR "Unable to register usb nop transceiver\n"); 49 return; 50 } 51} 52EXPORT_SYMBOL(usb_nop_xceiv_register); 53 54void usb_nop_xceiv_unregister(void) 55{ 56 platform_device_unregister(pd); 57 pd = NULL; 58} 59EXPORT_SYMBOL(usb_nop_xceiv_unregister); 60 61static int nop_set_suspend(struct usb_phy *x, int suspend) 62{ 63 return 0; 64} 65 66static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget) 67{ 68 if (!otg) 69 return -ENODEV; 70 71 if (!gadget) { 72 otg->gadget = NULL; 73 return -ENODEV; 74 } 75 76 otg->gadget = gadget; 77 otg->phy->state = OTG_STATE_B_IDLE; 78 return 0; 79} 80 81static int nop_set_host(struct usb_otg *otg, struct usb_bus *host) 82{ 83 if (!otg) 84 return -ENODEV; 85 86 if (!host) { 87 otg->host = NULL; 88 return -ENODEV; 89 } 90 91 otg->host = host; 92 return 0; 93} 94 95static int __devinit nop_usb_xceiv_probe(struct platform_device *pdev) 96{ 97 struct nop_usb_xceiv *nop; 98 int err; 99 100 nop = kzalloc(sizeof *nop, GFP_KERNEL); 101 if (!nop) 102 return -ENOMEM; 103 104 nop->phy.otg = kzalloc(sizeof *nop->phy.otg, GFP_KERNEL); 105 if (!nop->phy.otg) { 106 kfree(nop); 107 return -ENOMEM; 108 } 109 110 nop->dev = &pdev->dev; 111 nop->phy.dev = nop->dev; 112 nop->phy.label = "nop-xceiv"; 113 nop->phy.set_suspend = nop_set_suspend; 114 nop->phy.state = OTG_STATE_UNDEFINED; 115 116 nop->phy.otg->phy = &nop->phy; 117 nop->phy.otg->set_host = nop_set_host; 118 nop->phy.otg->set_peripheral = nop_set_peripheral; 119 120 err = usb_set_transceiver(&nop->phy); 121 if (err) { 122 dev_err(&pdev->dev, "can't register transceiver, err: %d\n", 123 err); 124 goto exit; 125 } 126 127 platform_set_drvdata(pdev, nop); 128 129 ATOMIC_INIT_NOTIFIER_HEAD(&nop->phy.notifier); 130 131 return 0; 132exit: 133 kfree(nop->phy.otg); 134 kfree(nop); 135 return err; 136} 137 138static int __devexit nop_usb_xceiv_remove(struct platform_device *pdev) 139{ 140 struct nop_usb_xceiv *nop = platform_get_drvdata(pdev); 141 142 usb_set_transceiver(NULL); 143 144 platform_set_drvdata(pdev, NULL); 145 kfree(nop->phy.otg); 146 kfree(nop); 147 148 return 0; 149} 150 151static struct platform_driver nop_usb_xceiv_driver = { 152 .probe = nop_usb_xceiv_probe, 153 .remove = __devexit_p(nop_usb_xceiv_remove), 154 .driver = { 155 .name = "nop_usb_xceiv", 156 .owner = THIS_MODULE, 157 }, 158}; 159 160static int __init nop_usb_xceiv_init(void) 161{ 162 return platform_driver_register(&nop_usb_xceiv_driver); 163} 164subsys_initcall(nop_usb_xceiv_init); 165 166static void __exit nop_usb_xceiv_exit(void) 167{ 168 platform_driver_unregister(&nop_usb_xceiv_driver); 169} 170module_exit(nop_usb_xceiv_exit); 171 172MODULE_ALIAS("platform:nop_usb_xceiv"); 173MODULE_AUTHOR("Texas Instruments Inc"); 174MODULE_DESCRIPTION("NOP USB Transceiver driver"); 175MODULE_LICENSE("GPL"); 176