136e56a34SAlan Stern /* 236e56a34SAlan Stern * drivers/usb/generic.c - generic driver for USB devices (not interfaces) 336e56a34SAlan Stern * 436e56a34SAlan Stern * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de> 536e56a34SAlan Stern * 636e56a34SAlan Stern * based on drivers/usb/usb.c which had the following copyrights: 736e56a34SAlan Stern * (C) Copyright Linus Torvalds 1999 836e56a34SAlan Stern * (C) Copyright Johannes Erdfelt 1999-2001 936e56a34SAlan Stern * (C) Copyright Andreas Gal 1999 1036e56a34SAlan Stern * (C) Copyright Gregory P. Smith 1999 1136e56a34SAlan Stern * (C) Copyright Deti Fliegl 1999 (new USB architecture) 1236e56a34SAlan Stern * (C) Copyright Randy Dunlap 2000 1336e56a34SAlan Stern * (C) Copyright David Brownell 2000-2004 1436e56a34SAlan Stern * (C) Copyright Yggdrasil Computing, Inc. 2000 1536e56a34SAlan Stern * (usb_device_id matching changes by Adam J. Richter) 1636e56a34SAlan Stern * (C) Copyright Greg Kroah-Hartman 2002-2003 1736e56a34SAlan Stern * 1836e56a34SAlan Stern */ 1936e56a34SAlan Stern 2036e56a34SAlan Stern #include <linux/usb.h> 2136e56a34SAlan Stern #include "usb.h" 22b6f6436dSAlan Stern #include "hcd.h" 2336e56a34SAlan Stern 24782da727SAlan Stern static inline const char *plural(int n) 25782da727SAlan Stern { 26782da727SAlan Stern return (n == 1 ? "" : "s"); 27782da727SAlan Stern } 28782da727SAlan Stern 29ad55d71aSOle Andre Vadla Ravnas static int is_rndis(struct usb_interface_descriptor *desc) 30ad55d71aSOle Andre Vadla Ravnas { 31ad55d71aSOle Andre Vadla Ravnas return desc->bInterfaceClass == USB_CLASS_COMM 32ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceSubClass == 2 33ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceProtocol == 0xff; 34ad55d71aSOle Andre Vadla Ravnas } 35ad55d71aSOle Andre Vadla Ravnas 36ad55d71aSOle Andre Vadla Ravnas static int is_activesync(struct usb_interface_descriptor *desc) 37ad55d71aSOle Andre Vadla Ravnas { 38ad55d71aSOle Andre Vadla Ravnas return desc->bInterfaceClass == USB_CLASS_MISC 39ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceSubClass == 1 40ad55d71aSOle Andre Vadla Ravnas && desc->bInterfaceProtocol == 1; 41ad55d71aSOle Andre Vadla Ravnas } 42ad55d71aSOle Andre Vadla Ravnas 43b5ea060fSGreg Kroah-Hartman int usb_choose_configuration(struct usb_device *udev) 44782da727SAlan Stern { 45782da727SAlan Stern int i; 46782da727SAlan Stern int num_configs; 47782da727SAlan Stern int insufficient_power = 0; 48782da727SAlan Stern struct usb_host_config *c, *best; 49782da727SAlan Stern 50782da727SAlan Stern best = NULL; 51782da727SAlan Stern c = udev->config; 52782da727SAlan Stern num_configs = udev->descriptor.bNumConfigurations; 53782da727SAlan Stern for (i = 0; i < num_configs; (i++, c++)) { 54782da727SAlan Stern struct usb_interface_descriptor *desc = NULL; 55782da727SAlan Stern 56782da727SAlan Stern /* It's possible that a config has no interfaces! */ 57782da727SAlan Stern if (c->desc.bNumInterfaces > 0) 58782da727SAlan Stern desc = &c->intf_cache[0]->altsetting->desc; 59782da727SAlan Stern 60782da727SAlan Stern /* 61782da727SAlan Stern * HP's USB bus-powered keyboard has only one configuration 62782da727SAlan Stern * and it claims to be self-powered; other devices may have 63782da727SAlan Stern * similar errors in their descriptors. If the next test 64782da727SAlan Stern * were allowed to execute, such configurations would always 65782da727SAlan Stern * be rejected and the devices would not work as expected. 66782da727SAlan Stern * In the meantime, we run the risk of selecting a config 67782da727SAlan Stern * that requires external power at a time when that power 68782da727SAlan Stern * isn't available. It seems to be the lesser of two evils. 69782da727SAlan Stern * 70782da727SAlan Stern * Bugzilla #6448 reports a device that appears to crash 71782da727SAlan Stern * when it receives a GET_DEVICE_STATUS request! We don't 72782da727SAlan Stern * have any other way to tell whether a device is self-powered, 73782da727SAlan Stern * but since we don't use that information anywhere but here, 74782da727SAlan Stern * the call has been removed. 75782da727SAlan Stern * 76782da727SAlan Stern * Maybe the GET_DEVICE_STATUS call and the test below can 77782da727SAlan Stern * be reinstated when device firmwares become more reliable. 78782da727SAlan Stern * Don't hold your breath. 79782da727SAlan Stern */ 80782da727SAlan Stern #if 0 81782da727SAlan Stern /* Rule out self-powered configs for a bus-powered device */ 82782da727SAlan Stern if (bus_powered && (c->desc.bmAttributes & 83782da727SAlan Stern USB_CONFIG_ATT_SELFPOWER)) 84782da727SAlan Stern continue; 85782da727SAlan Stern #endif 86782da727SAlan Stern 87782da727SAlan Stern /* 88782da727SAlan Stern * The next test may not be as effective as it should be. 89782da727SAlan Stern * Some hubs have errors in their descriptor, claiming 90782da727SAlan Stern * to be self-powered when they are really bus-powered. 91782da727SAlan Stern * We will overestimate the amount of current such hubs 92782da727SAlan Stern * make available for each port. 93782da727SAlan Stern * 94782da727SAlan Stern * This is a fairly benign sort of failure. It won't 95782da727SAlan Stern * cause us to reject configurations that we should have 96782da727SAlan Stern * accepted. 97782da727SAlan Stern */ 98782da727SAlan Stern 99782da727SAlan Stern /* Rule out configs that draw too much bus current */ 100782da727SAlan Stern if (c->desc.bMaxPower * 2 > udev->bus_mA) { 101782da727SAlan Stern insufficient_power++; 102782da727SAlan Stern continue; 103782da727SAlan Stern } 104782da727SAlan Stern 105ad55d71aSOle Andre Vadla Ravnas /* When the first config's first interface is one of Microsoft's 106ad55d71aSOle Andre Vadla Ravnas * pet nonstandard Ethernet-over-USB protocols, ignore it unless 107ad55d71aSOle Andre Vadla Ravnas * this kernel has enabled the necessary host side driver. 108ad55d71aSOle Andre Vadla Ravnas */ 109ad55d71aSOle Andre Vadla Ravnas if (i == 0 && desc && (is_rndis(desc) || is_activesync(desc))) { 110ad55d71aSOle Andre Vadla Ravnas #if !defined(CONFIG_USB_NET_RNDIS_HOST) && !defined(CONFIG_USB_NET_RNDIS_HOST_MODULE) 111782da727SAlan Stern continue; 112782da727SAlan Stern #else 113782da727SAlan Stern best = c; 114782da727SAlan Stern #endif 115782da727SAlan Stern } 116782da727SAlan Stern 117782da727SAlan Stern /* From the remaining configs, choose the first one whose 118782da727SAlan Stern * first interface is for a non-vendor-specific class. 119782da727SAlan Stern * Reason: Linux is more likely to have a class driver 120782da727SAlan Stern * than a vendor-specific driver. */ 121782da727SAlan Stern else if (udev->descriptor.bDeviceClass != 122782da727SAlan Stern USB_CLASS_VENDOR_SPEC && 123782da727SAlan Stern (!desc || desc->bInterfaceClass != 124782da727SAlan Stern USB_CLASS_VENDOR_SPEC)) { 125782da727SAlan Stern best = c; 126782da727SAlan Stern break; 127782da727SAlan Stern } 128782da727SAlan Stern 129782da727SAlan Stern /* If all the remaining configs are vendor-specific, 130782da727SAlan Stern * choose the first one. */ 131782da727SAlan Stern else if (!best) 132782da727SAlan Stern best = c; 133782da727SAlan Stern } 134782da727SAlan Stern 135782da727SAlan Stern if (insufficient_power > 0) 136782da727SAlan Stern dev_info(&udev->dev, "rejected %d configuration%s " 137782da727SAlan Stern "due to insufficient available bus power\n", 138782da727SAlan Stern insufficient_power, plural(insufficient_power)); 139782da727SAlan Stern 140782da727SAlan Stern if (best) { 141782da727SAlan Stern i = best->desc.bConfigurationValue; 142782da727SAlan Stern dev_info(&udev->dev, 143782da727SAlan Stern "configuration #%d chosen from %d choice%s\n", 144782da727SAlan Stern i, num_configs, plural(num_configs)); 145782da727SAlan Stern } else { 146782da727SAlan Stern i = -1; 147782da727SAlan Stern dev_warn(&udev->dev, 148782da727SAlan Stern "no configuration chosen from %d choice%s\n", 149782da727SAlan Stern num_configs, plural(num_configs)); 150782da727SAlan Stern } 151782da727SAlan Stern return i; 152782da727SAlan Stern } 153782da727SAlan Stern 1548bb54ab5SAlan Stern static int generic_probe(struct usb_device *udev) 15536e56a34SAlan Stern { 156782da727SAlan Stern int err, c; 157782da727SAlan Stern 158782da727SAlan Stern /* Choose and set the configuration. This registers the interfaces 159782da727SAlan Stern * with the driver core and lets interface drivers bind to them. 160782da727SAlan Stern */ 161f8a37464SInaky Perez-Gonzalez if (udev->authorized == 0) 162f8a37464SInaky Perez-Gonzalez dev_err(&udev->dev, "Device is not authorized for usage\n"); 163f8a37464SInaky Perez-Gonzalez else { 164b5ea060fSGreg Kroah-Hartman c = usb_choose_configuration(udev); 165782da727SAlan Stern if (c >= 0) { 166782da727SAlan Stern err = usb_set_configuration(udev, c); 167782da727SAlan Stern if (err) { 168782da727SAlan Stern dev_err(&udev->dev, "can't set config #%d, error %d\n", 169782da727SAlan Stern c, err); 170782da727SAlan Stern /* This need not be fatal. The user can try to 171782da727SAlan Stern * set other configurations. */ 172782da727SAlan Stern } 173782da727SAlan Stern } 174f8a37464SInaky Perez-Gonzalez } 175782da727SAlan Stern /* USB device state == configured ... usable */ 176782da727SAlan Stern usb_notify_add_device(udev); 177782da727SAlan Stern 17836e56a34SAlan Stern return 0; 17936e56a34SAlan Stern } 180782da727SAlan Stern 1818bb54ab5SAlan Stern static void generic_disconnect(struct usb_device *udev) 18236e56a34SAlan Stern { 183782da727SAlan Stern usb_notify_remove_device(udev); 184782da727SAlan Stern 18536e56a34SAlan Stern /* if this is only an unbind, not a physical disconnect, then 18636e56a34SAlan Stern * unconfigure the device */ 18701d883d4SAlan Stern if (udev->actconfig) 1883f141e2aSAlan Stern usb_set_configuration(udev, -1); 18936e56a34SAlan Stern } 19036e56a34SAlan Stern 191782da727SAlan Stern #ifdef CONFIG_PM 192782da727SAlan Stern 193782da727SAlan Stern static int generic_suspend(struct usb_device *udev, pm_message_t msg) 194782da727SAlan Stern { 195b6f6436dSAlan Stern int rc; 196b6f6436dSAlan Stern 197686314cfSAlan Stern /* Normal USB devices suspend through their upstream port. 198686314cfSAlan Stern * Root hubs don't have upstream ports to suspend, 199686314cfSAlan Stern * so we have to shut down their downstream HC-to-USB 200686314cfSAlan Stern * interfaces manually by doing a bus (or "global") suspend. 201b6f6436dSAlan Stern */ 202686314cfSAlan Stern if (!udev->parent) 20365bfd296SAlan Stern rc = hcd_bus_suspend(udev, msg); 2045ad4f71eSAlan Stern 2055ad4f71eSAlan Stern /* Non-root devices don't need to do anything for FREEZE or PRETHAW */ 2065ad4f71eSAlan Stern else if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_PRETHAW) 2075ad4f71eSAlan Stern rc = 0; 208686314cfSAlan Stern else 20965bfd296SAlan Stern rc = usb_port_suspend(udev, msg); 2105ad4f71eSAlan Stern 211b6f6436dSAlan Stern return rc; 212782da727SAlan Stern } 213782da727SAlan Stern 21465bfd296SAlan Stern static int generic_resume(struct usb_device *udev, pm_message_t msg) 215782da727SAlan Stern { 216b6f6436dSAlan Stern int rc; 217b6f6436dSAlan Stern 218686314cfSAlan Stern /* Normal USB devices resume/reset through their upstream port. 219686314cfSAlan Stern * Root hubs don't have upstream ports to resume or reset, 220686314cfSAlan Stern * so we have to start up their downstream HC-to-USB 221686314cfSAlan Stern * interfaces manually by doing a bus (or "global") resume. 222686314cfSAlan Stern */ 223686314cfSAlan Stern if (!udev->parent) 22465bfd296SAlan Stern rc = hcd_bus_resume(udev, msg); 2250458d5b4SAlan Stern else 22665bfd296SAlan Stern rc = usb_port_resume(udev, msg); 227b6f6436dSAlan Stern return rc; 228782da727SAlan Stern } 229782da727SAlan Stern 230782da727SAlan Stern #endif /* CONFIG_PM */ 231782da727SAlan Stern 2328bb54ab5SAlan Stern struct usb_device_driver usb_generic_driver = { 23336e56a34SAlan Stern .name = "usb", 23436e56a34SAlan Stern .probe = generic_probe, 2358bb54ab5SAlan Stern .disconnect = generic_disconnect, 236782da727SAlan Stern #ifdef CONFIG_PM 237782da727SAlan Stern .suspend = generic_suspend, 238782da727SAlan Stern .resume = generic_resume, 239782da727SAlan Stern #endif 24001d883d4SAlan Stern .supports_autosuspend = 1, 24136e56a34SAlan Stern }; 242