246 lines
6.9 KiB
C
246 lines
6.9 KiB
C
/*
|
|
* drivers/usb/generic.c - generic driver for USB devices (not interfaces)
|
|
*
|
|
* (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
|
|
*
|
|
* based on drivers/usb/usb.c which had the following copyrights:
|
|
* (C) Copyright Linus Torvalds 1999
|
|
* (C) Copyright Johannes Erdfelt 1999-2001
|
|
* (C) Copyright Andreas Gal 1999
|
|
* (C) Copyright Gregory P. Smith 1999
|
|
* (C) Copyright Deti Fliegl 1999 (new USB architecture)
|
|
* (C) Copyright Randy Dunlap 2000
|
|
* (C) Copyright David Brownell 2000-2004
|
|
* (C) Copyright Yggdrasil Computing, Inc. 2000
|
|
* (usb_device_id matching changes by Adam J. Richter)
|
|
* (C) Copyright Greg Kroah-Hartman 2002-2003
|
|
*
|
|
*/
|
|
|
|
#include <linux/usb.h>
|
|
#include <linux/usb/hcd.h>
|
|
#include "usb.h"
|
|
|
|
static inline const char *plural(int n)
|
|
{
|
|
return (n == 1 ? "" : "s");
|
|
}
|
|
|
|
static int is_rndis(struct usb_interface_descriptor *desc)
|
|
{
|
|
return desc->bInterfaceClass == USB_CLASS_COMM
|
|
&& desc->bInterfaceSubClass == 2
|
|
&& desc->bInterfaceProtocol == 0xff;
|
|
}
|
|
|
|
static int is_activesync(struct usb_interface_descriptor *desc)
|
|
{
|
|
return desc->bInterfaceClass == USB_CLASS_MISC
|
|
&& desc->bInterfaceSubClass == 1
|
|
&& desc->bInterfaceProtocol == 1;
|
|
}
|
|
|
|
int usb_choose_configuration(struct usb_device *udev)
|
|
{
|
|
int i;
|
|
int num_configs;
|
|
int insufficient_power = 0;
|
|
struct usb_host_config *c, *best;
|
|
|
|
best = NULL;
|
|
c = udev->config;
|
|
num_configs = udev->descriptor.bNumConfigurations;
|
|
for (i = 0; i < num_configs; (i++, c++)) {
|
|
struct usb_interface_descriptor *desc = NULL;
|
|
|
|
/* It's possible that a config has no interfaces! */
|
|
if (c->desc.bNumInterfaces > 0)
|
|
desc = &c->intf_cache[0]->altsetting->desc;
|
|
|
|
/*
|
|
* HP's USB bus-powered keyboard has only one configuration
|
|
* and it claims to be self-powered; other devices may have
|
|
* similar errors in their descriptors. If the next test
|
|
* were allowed to execute, such configurations would always
|
|
* be rejected and the devices would not work as expected.
|
|
* In the meantime, we run the risk of selecting a config
|
|
* that requires external power at a time when that power
|
|
* isn't available. It seems to be the lesser of two evils.
|
|
*
|
|
* Bugzilla #6448 reports a device that appears to crash
|
|
* when it receives a GET_DEVICE_STATUS request! We don't
|
|
* have any other way to tell whether a device is self-powered,
|
|
* but since we don't use that information anywhere but here,
|
|
* the call has been removed.
|
|
*
|
|
* Maybe the GET_DEVICE_STATUS call and the test below can
|
|
* be reinstated when device firmwares become more reliable.
|
|
* Don't hold your breath.
|
|
*/
|
|
#if 0
|
|
/* Rule out self-powered configs for a bus-powered device */
|
|
if (bus_powered && (c->desc.bmAttributes &
|
|
USB_CONFIG_ATT_SELFPOWER))
|
|
continue;
|
|
#endif
|
|
|
|
/*
|
|
* The next test may not be as effective as it should be.
|
|
* Some hubs have errors in their descriptor, claiming
|
|
* to be self-powered when they are really bus-powered.
|
|
* We will overestimate the amount of current such hubs
|
|
* make available for each port.
|
|
*
|
|
* This is a fairly benign sort of failure. It won't
|
|
* cause us to reject configurations that we should have
|
|
* accepted.
|
|
*/
|
|
|
|
/* Rule out configs that draw too much bus current */
|
|
if (c->desc.bMaxPower * 2 > udev->bus_mA) {
|
|
insufficient_power++;
|
|
continue;
|
|
}
|
|
|
|
/* When the first config's first interface is one of Microsoft's
|
|
* pet nonstandard Ethernet-over-USB protocols, ignore it unless
|
|
* this kernel has enabled the necessary host side driver.
|
|
* But: Don't ignore it if it's the only config.
|
|
*/
|
|
if (i == 0 && num_configs > 1 && desc &&
|
|
(is_rndis(desc) || is_activesync(desc))) {
|
|
#if !defined(CONFIG_USB_NET_RNDIS_HOST) && !defined(CONFIG_USB_NET_RNDIS_HOST_MODULE)
|
|
continue;
|
|
#else
|
|
best = c;
|
|
#endif
|
|
}
|
|
|
|
/* From the remaining configs, choose the first one whose
|
|
* first interface is for a non-vendor-specific class.
|
|
* Reason: Linux is more likely to have a class driver
|
|
* than a vendor-specific driver. */
|
|
else if (udev->descriptor.bDeviceClass !=
|
|
USB_CLASS_VENDOR_SPEC &&
|
|
(desc && desc->bInterfaceClass !=
|
|
USB_CLASS_VENDOR_SPEC)) {
|
|
best = c;
|
|
break;
|
|
}
|
|
|
|
/* If all the remaining configs are vendor-specific,
|
|
* choose the first one. */
|
|
else if (!best)
|
|
best = c;
|
|
}
|
|
|
|
if (insufficient_power > 0)
|
|
dev_info(&udev->dev, "rejected %d configuration%s "
|
|
"due to insufficient available bus power\n",
|
|
insufficient_power, plural(insufficient_power));
|
|
|
|
if (best) {
|
|
i = best->desc.bConfigurationValue;
|
|
dev_dbg(&udev->dev,
|
|
"configuration #%d chosen from %d choice%s\n",
|
|
i, num_configs, plural(num_configs));
|
|
} else {
|
|
i = -1;
|
|
dev_warn(&udev->dev,
|
|
"no configuration chosen from %d choice%s\n",
|
|
num_configs, plural(num_configs));
|
|
}
|
|
return i;
|
|
}
|
|
|
|
static int generic_probe(struct usb_device *udev)
|
|
{
|
|
int err, c;
|
|
|
|
/* Choose and set the configuration. This registers the interfaces
|
|
* with the driver core and lets interface drivers bind to them.
|
|
*/
|
|
if (usb_device_is_owned(udev))
|
|
; /* Don't configure if the device is owned */
|
|
else if (udev->authorized == 0)
|
|
dev_err(&udev->dev, "Device is not authorized for usage\n");
|
|
else {
|
|
c = usb_choose_configuration(udev);
|
|
if (c >= 0) {
|
|
err = usb_set_configuration(udev, c);
|
|
if (err) {
|
|
dev_err(&udev->dev, "can't set config #%d, error %d\n",
|
|
c, err);
|
|
/* This need not be fatal. The user can try to
|
|
* set other configurations. */
|
|
}
|
|
}
|
|
}
|
|
/* USB device state == configured ... usable */
|
|
usb_notify_add_device(udev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void generic_disconnect(struct usb_device *udev)
|
|
{
|
|
usb_notify_remove_device(udev);
|
|
|
|
/* if this is only an unbind, not a physical disconnect, then
|
|
* unconfigure the device */
|
|
if (udev->actconfig)
|
|
usb_set_configuration(udev, -1);
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
|
|
static int generic_suspend(struct usb_device *udev, pm_message_t msg)
|
|
{
|
|
int rc;
|
|
|
|
/* Normal USB devices suspend through their upstream port.
|
|
* Root hubs don't have upstream ports to suspend,
|
|
* so we have to shut down their downstream HC-to-USB
|
|
* interfaces manually by doing a bus (or "global") suspend.
|
|
*/
|
|
if (!udev->parent)
|
|
rc = hcd_bus_suspend(udev, msg);
|
|
|
|
/* Non-root devices don't need to do anything for FREEZE or PRETHAW */
|
|
else if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_PRETHAW)
|
|
rc = 0;
|
|
else
|
|
rc = usb_port_suspend(udev, msg);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int generic_resume(struct usb_device *udev, pm_message_t msg)
|
|
{
|
|
int rc;
|
|
|
|
/* Normal USB devices resume/reset through their upstream port.
|
|
* Root hubs don't have upstream ports to resume or reset,
|
|
* so we have to start up their downstream HC-to-USB
|
|
* interfaces manually by doing a bus (or "global") resume.
|
|
*/
|
|
if (!udev->parent)
|
|
rc = hcd_bus_resume(udev, msg);
|
|
else
|
|
rc = usb_port_resume(udev, msg);
|
|
return rc;
|
|
}
|
|
|
|
#endif /* CONFIG_PM */
|
|
|
|
struct usb_device_driver usb_generic_driver = {
|
|
.name = "usb",
|
|
.probe = generic_probe,
|
|
.disconnect = generic_disconnect,
|
|
#ifdef CONFIG_PM
|
|
.suspend = generic_suspend,
|
|
.resume = generic_resume,
|
|
#endif
|
|
.supports_autosuspend = 1,
|
|
};
|