Commit 37b05b17 authored by Linus Torvalds's avatar Linus Torvalds

Merge git://

* git:// (120 commits)
  usb: don't update devnum for wusb devices
  wusb: make ep0_reinit available for modules
  wusb: devices dont use a set address
  wusb: teach choose_address() about wireless devices
  wusb: add link wusb-usb device
  wusb: add authenticathed bit to usb_dev
  USB: remove unnecessary type casting of urb->context
  usb serial: more fixes and groundwork for tty changes
  USB: replace remaining __FUNCTION__ occurrences
  USB: usbfs: export the URB_NO_INTERRUPT flag to userspace
  USB: fix compile problems in ehci-hcd
  USB: ehci: qh_completions cleanup and bugfix
  USB: cdc-acm: signedness fix
  USB: add documentation about callbacks
  USB: don't explicitly reenable root-hub status interrupts
  USB: OHCI: turn off RD when remote wakeup is disabled
  USB: HCDs use the do_remote_wakeup flag
  USB: g_file_storage: ignore bulk-out data after invalid CBW
  USB: serial: remove endpoints setting checks from core and header
  USB: serial: remove unneeded number endpoints settings
parents ce1d5b23 4953d141
What is anchor?
A USB driver needs to support some callbacks requiring
a driver to cease all IO to an interface. To do so, a
driver has to keep track of the URBs it has submitted
to know they've all completed or to call usb_kill_urb
for them. The anchor is a data structure takes care of
keeping track of URBs and provides methods to deal with
multiple URBs.
Allocation and Initialisation
There's no API to allocate an anchor. It is simply declared
as struct usb_anchor. init_usb_anchor() must be called to
initialise the data structure.
Once it has no more URBs associated with it, the anchor can be
freed with normal memory management operations.
Association and disassociation of URBs with anchors
An association of URBs to an anchor is made by an explicit
call to usb_anchor_urb(). The association is maintained until
an URB is finished by (successfull) completion. Thus disassociation
is automatic. A function is provided to forcibly finish (kill)
all URBs associated with an anchor.
Furthermore, disassociation can be made with usb_unanchor_urb()
Operations on multitudes of URBs
This function kills all URBs associated with an anchor. The URBs
are called in the reverse temporal order they were submitted.
This way no data can be reordered.
This function waits for all URBs associated with an anchor to finish
or a timeout, whichever comes first. Its return value will tell you
whether the timeout was reached.
What callbacks will usbcore do?
Usbcore will call into a driver through callbacks defined in the driver
structure and through the completion handler of URBs a driver submits.
Only the former are in the scope of this document. These two kinds of
callbacks are completely independent of each other. Information on the
completion callback can be found in Documentation/usb/URB.txt.
The callbacks defined in the driver structure are:
1. Hotplugging callbacks:
* @probe: Called to see if the driver is willing to manage a particular
* interface on a device.
* @disconnect: Called when the interface is no longer accessible, usually
* because its device has been (or is being) disconnected or the
* driver module is being unloaded.
2. Odd backdoor through usbfs:
* @ioctl: Used for drivers that want to talk to userspace through
* the "usbfs" filesystem. This lets devices provide ways to
* expose information to user space regardless of where they
* do (or don't) show up otherwise in the filesystem.
3. Power management (PM) callbacks:
* @suspend: Called when the device is going to be suspended.
* @resume: Called when the device is being resumed.
* @reset_resume: Called when the suspended device has been reset instead
* of being resumed.
4. Device level operations:
* @pre_reset: Called when the device is about to be reset.
* @post_reset: Called after the device has been reset
The ioctl interface (2) should be used only if you have a very good
reason. Sysfs is preferred these days. The PM callbacks are covered
separately in Documentation/usb/power-management.txt.
Calling conventions
All callbacks are mutually exclusive. There's no need for locking
against other USB callbacks. All callbacks are called from a task
context. You may sleep. However, it is important that all sleeps have a
small fixed upper limit in time. In particular you must not call out to
user space and await results.
Hotplugging callbacks
These callbacks are intended to associate and disassociate a driver with
an interface. A driver's bond to an interface is exclusive.
The probe() callback
int (*probe) (struct usb_interface *intf,
const struct usb_device_id *id);
Accept or decline an interface. If you accept the device return 0,
otherwise -ENODEV or -ENXIO. Other error codes should be used only if a
genuine error occurred during initialisation which prevented a driver
from accepting a device that would else have been accepted.
You are strongly encouraged to use usbcore'sfacility,
usb_set_intfdata(), to associate a data structure with an interface, so
that you know which internal state and identity you associate with a
particular interface. The device will not be suspended and you may do IO
to the interface you are called for and endpoint 0 of the device. Device
initialisation that doesn't take too long is a good idea here.
The disconnect() callback
void (*disconnect) (struct usb_interface *intf);
This callback is a signal to break any connection with an interface.
You are not allowed any IO to a device after returning from this
callback. You also may not do any other operation that may interfere
with another driver bound the interface, eg. a power management
If you are called due to a physical disconnection, all your URBs will be
killed by usbcore. Note that in this case disconnect will be called some
time after the physical disconnection. Thus your driver must be prepared
to deal with failing IO even prior to the callback.
Device level callbacks
int (*pre_reset)(struct usb_interface *intf);
Another driver or user space is triggering a reset on the device which
contains the interface passed as an argument. Cease IO and save any
device state you need to restore.
If you need to allocate memory here, use GFP_NOIO or GFP_ATOMIC, if you
are in atomic context.
int (*post_reset)(struct usb_interface *intf);
The reset has completed. Restore any saved device state and begin
using the device again.
If you need to allocate memory here, use GFP_NOIO or GFP_ATOMIC, if you
are in atomic context.
Call sequences
No callbacks other than probe will be invoked for an interface
that isn't bound to your driver.
Probe will never be called for an interface bound to a driver.
Hence following a successful probe, disconnect will be called
before there is another probe for the same interface.
Once your driver is bound to an interface, disconnect can be
called at any time except in between pre_reset and post_reset.
pre_reset is always followed by post_reset, even if the reset
failed or the device has been unplugged.
suspend is always followed by one of: resume, reset_resume, or
......@@ -2,7 +2,7 @@
Alan Stern <>
September 2, 2006 (Updated May 29, 2007)
September 2, 2006 (Updated February 25, 2008)
What is the problem?
......@@ -65,9 +65,10 @@ much better.)
What is the solution?
Setting CONFIG_USB_PERSIST will cause the kernel to work around these
issues. It enables a mode in which the core USB device data
structures are allowed to persist across a power-session disruption.
The kernel includes a feature called USB-persist. It tries to work
around these issues by allowing the core USB device data structures to
persist across a power-session disruption.
It works like this. If the kernel sees that a USB host controller is
not in the expected state during resume (i.e., if the controller was
reset or otherwise had lost power) then it applies a persistence check
......@@ -80,28 +81,30 @@ re-enumeration shows that the device now attached to that port has the
same descriptors as before, including the Vendor and Product IDs, then
the kernel continues to use the same device structure. In effect, the
kernel treats the device as though it had merely been reset instead of
unplugged. The same thing happens if the host controller is in the
expected state but a USB device was unplugged and then replugged.
If no device is now attached to the port, or if the descriptors are
different from what the kernel remembers, then the treatment is what
you would expect. The kernel destroys the old device structure and
behaves as though the old device had been unplugged and a new device
plugged in, just as it would without the CONFIG_USB_PERSIST option.
plugged in.
The end result is that the USB device remains available and usable.
Filesystem mounts and memory mappings are unaffected, and the world is
now a good and happy place.
Note that even when CONFIG_USB_PERSIST is set, the "persist" feature
will be applied only to those devices for which it is enabled. You
can enable the feature by doing (as root):
Note that the "USB-persist" feature will be applied only to those
devices for which it is enabled. You can enable the feature by doing
(as root):
echo 1 >/sys/bus/usb/devices/.../power/persist
where the "..." should be filled in the with the device's ID. Disable
the feature by writing 0 instead of 1. For hubs the feature is
automatically and permanently enabled, so you only have to worry about
setting it for devices where it really matters.
automatically and permanently enabled and the power/persist file
doesn't even exist, so you only have to worry about setting it for
devices where it really matters.
Is this the best solution?
......@@ -112,19 +115,19 @@ centralized Logical Volume Manager. Such a solution would allow you
to plug in a USB flash device, create a persistent volume associated
with it, unplug the flash device, plug it back in later, and still
have the same persistent volume associated with the device. As such
it would be more far-reaching than CONFIG_USB_PERSIST.
it would be more far-reaching than USB-persist.
On the other hand, writing a persistent volume manager would be a big
job and using it would require significant input from the user. This
solution is much quicker and easier -- and it exists now, a giant
point in its favor!
Furthermore, the USB_PERSIST option applies to _all_ USB devices, not
Furthermore, the USB-persist feature applies to _all_ USB devices, not
just mass-storage devices. It might turn out to be equally useful for
other device types, such as network interfaces.
WARNING: Using CONFIG_USB_PERSIST can be dangerous!!
WARNING: USB-persist can be dangerous!!
When recovering an interrupted power session the kernel does its best
to make sure the USB device hasn't been changed; that is, the same
......@@ -133,10 +136,10 @@ aren't guaranteed to be 100% accurate.
If you replace one USB device with another of the same type (same
manufacturer, same IDs, and so on) there's an excellent chance the
kernel won't detect the change. Serial numbers and other strings are
not compared. In many cases it wouldn't help if they were, because
manufacturers frequently omit serial numbers entirely in their
kernel won't detect the change. The serial number string and other
descriptors are compared with the kernel's stored values, but this
might not help since manufacturers frequently omit serial numbers
entirely in their devices.
Furthermore it's quite possible to leave a USB device exactly the same
while changing its media. If you replace the flash memory card in a
......@@ -152,5 +155,5 @@ but yourself.
That having been said, most of the time there shouldn't be any trouble
at all. The "persist" feature can be extremely useful. Make the most
of it.
at all. The USB-persist feature can be extremely useful. Make the
most of it.
......@@ -192,12 +192,9 @@ Keyspan USA-series Serial Adapters
FTDI Single Port Serial Driver
This is a single port DB-25 serial adapter. More information about this
device and the Linux driver can be found at:
This is a single port DB-25 serial adapter.
For any questions or problems with this driver, please contact Bill Ryder
For any questions or problems with this driver, please contact Bill Ryder.
ZyXEL lcd plus ISDN TA
......@@ -405,9 +405,11 @@ static void xpad360w_process_packet(struct usb_xpad *xpad, u16 cmd, unsigned cha
static void xpad_irq_in(struct urb *urb)
struct usb_xpad *xpad = urb->context;
int retval;
int retval, status;
switch (urb->status) {
status = urb->status;
switch (status) {
case 0:
/* success */
......@@ -416,11 +418,11 @@ static void xpad_irq_in(struct urb *urb)
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d",
__FUNCTION__, urb->status);
__FUNCTION__, status);
dbg("%s - nonzero urb status received: %d",
__FUNCTION__, urb->status);
__FUNCTION__, status);
goto exit;
......@@ -445,9 +447,11 @@ exit:
static void xpad_irq_out(struct urb *urb)
int retval;
int retval, status;
switch (urb->status) {
status = urb->status;
switch (status) {
case 0:
/* success */
......@@ -456,11 +460,11 @@ static void xpad_irq_out(struct urb *urb)
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d",
__FUNCTION__, urb->status);
__FUNCTION__, status);
dbg("%s - nonzero urb status received: %d",
__FUNCTION__, urb->status);
__FUNCTION__, status);
goto exit;
......@@ -444,7 +444,7 @@ CXACRU_ALL_FILES(INIT);
/* the following three functions are stolen from drivers/usb/core/message.c */
static void cxacru_blocking_completion(struct urb *urb)
complete((struct completion *)urb->context);
static void cxacru_timeout_kill(unsigned long data)
......@@ -83,7 +83,7 @@
if (debug >= 1) \
dev_dbg(&(usb_dev)->dev, \
"[ueagle-atm dbg] %s: " format, \
__FUNCTION__, ##args); \
__func__, ##args); \
} while (0)
#define uea_vdbg(usb_dev, format, args...) \
......@@ -94,10 +94,10 @@
} while (0)
#define uea_enters(usb_dev) \
uea_vdbg(usb_dev, "entering %s\n", __FUNCTION__)
uea_vdbg(usb_dev, "entering %s\n", __func__)
#define uea_leaves(usb_dev) \
uea_vdbg(usb_dev, "leaving %s\n", __FUNCTION__)
uea_vdbg(usb_dev, "leaving %s\n", __func__)
#define uea_err(usb_dev, format,args...) \
dev_err(&(usb_dev)->dev ,"[UEAGLE-ATM] " format , ##args)
......@@ -80,6 +80,7 @@
#include <linux/stat.h>
#include <linux/timer.h>
#include <linux/wait.h>
#include <linux/kthread.h>
static int usbatm_print_packet(const unsigned char *data, int len);
......@@ -1014,10 +1015,7 @@ static int usbatm_do_heavy_init(void *arg)
struct usbatm_data *instance = arg;
int ret;
instance->thread_pid = current->pid;
ret = instance->driver->heavy_init(instance, instance->usb_intf);
......@@ -1026,7 +1024,7 @@ static int usbatm_do_heavy_init(void *arg)
ret = usbatm_atm_init(instance);
instance->thread_pid = -1;
instance->thread = NULL;
complete_and_exit(&instance->thread_exited, ret);
......@@ -1034,13 +1032,18 @@ static int usbatm_do_heavy_init(void *arg)
static int usbatm_heavy_init(struct usbatm_data *instance)
int ret = kernel_thread(usbatm_do_heavy_init, instance, CLONE_FS | CLONE_FILES);
if (ret < 0) {
usb_err(instance, "%s: failed to create kernel_thread (%d)!\n", __func__, ret);
return ret;
struct task_struct *t;
t = kthread_create(usbatm_do_heavy_init, instance,
if (IS_ERR(t)) {
usb_err(instance, "%s: failed to create kernel_thread (%ld)!\n",
__func__, PTR_ERR(t));
return PTR_ERR(t);
instance->thread = t;
return 0;
......@@ -1124,7 +1127,7 @@ int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id,
kref_init(&instance->refcount); /* dropped in usbatm_usb_disconnect */
instance->thread_pid = -1;
instance->thread = NULL;
......@@ -1287,8 +1290,8 @@ void usbatm_usb_disconnect(struct usb_interface *intf)
instance->disconnected = 1;
if (instance->thread_pid >= 0)
kill_proc(instance->thread_pid, SIGTERM, 1);
if (instance->thread != NULL)
send_sig(SIGTERM, instance->thread, 1);
......@@ -175,7 +175,7 @@ struct usbatm_data {
int disconnected;
/* heavy init */
int thread_pid;
struct task_struct *thread;
struct completion thread_started;
struct completion thread_exited;
......@@ -31,6 +31,7 @@
* v0.23 - use softirq for rx processing, as needed by tty layer
* v0.24 - change probe method to evaluate CDC union descriptor
* v0.25 - downstream tasks paralelized to maximize throughput
* v0.26 - multiple write urbs, writesize increased
......@@ -72,7 +73,7 @@
* Version Information
#define DRIVER_VERSION "v0.25"
#define DRIVER_VERSION "v0.26"
#define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek"
#define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
......@@ -118,7 +119,7 @@ static int acm_wb_alloc(struct acm *acm)
int i, wbn;
struct acm_wb *wb;
wbn = acm->write_current;
wbn = 0;
i = 0;
for (;;) {
wb = &acm->wb[wbn];
......@@ -132,11 +133,6 @@ static int acm_wb_alloc(struct acm *acm)
static void acm_wb_free(struct acm *acm, int wbn)
acm->wb[wbn].use = 0;
static int acm_wb_is_avail(struct acm *acm)
int i, n;
......@@ -156,26 +152,22 @@ static inline int acm_wb_is_used(struct acm *acm, int wbn)
* Finish write.
static void acm_write_done(struct acm *acm)
static void acm_write_done(struct acm *acm, struct acm_wb *wb)
unsigned long flags;
int wbn;
spin_lock_irqsave(&acm->write_lock, flags);
acm->write_ready = 1;
wbn = acm->write_current;
acm_wb_free(acm, wbn);
acm->write_current = (wbn + 1) % ACM_NW;
wb->use = 0;
spin_unlock_irqrestore(&acm->write_lock, flags);
* Poke write.
static int acm_write_start(struct acm *acm)
static int acm_write_start(struct acm *acm, int wbn)
unsigned long flags;
int wbn;
struct acm_wb *wb;
int rc;
......@@ -190,24 +182,24 @@ static int acm_write_start(struct acm *acm)
return 0; /* A white lie */
wbn = acm->write_current;
if (!acm_wb_is_used(acm, wbn)) {
spin_unlock_irqrestore(&acm->write_lock, flags);
return 0;
wb = &acm->wb[wbn];
acm->write_ready = 0;
if(acm_wb_is_avail(acm) <= 1)
acm->write_ready = 0;
spin_unlock_irqrestore(&acm->write_lock, flags);
acm->writeurb->transfer_buffer = wb->buf;
acm->writeurb->transfer_dma = wb->dmah;
acm->writeurb->transfer_buffer_length = wb->len;
acm->writeurb->dev = acm->dev;
wb->urb->transfer_buffer = wb->buf;
wb->urb->transfer_dma = wb->dmah;
wb->urb->transfer_buffer_length = wb->len;
wb->urb->dev = acm->dev;
if ((rc = usb_submit_urb(acm->writeurb, GFP_ATOMIC)) < 0) {
if ((rc = usb_submit_urb(wb->urb, GFP_ATOMIC)) < 0) {
dbg("usb_submit_urb(write bulk) failed: %d", rc);
acm_write_done(acm, wb);
return rc;
......@@ -268,10 +260,10 @@ static void acm_ctrl_irq(struct urb *urb)
case -ENOENT:
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d", __FUNCTION__, status);
dbg("%s - urb shutting down with status: %d", __func__, status);
dbg("%s - nonzero urb status received: %d", __FUNCTION__, status);
dbg("%s - nonzero urb status received: %d", __func__, status);
goto exit;
......@@ -315,7 +307,7 @@ exit:
retval = usb_submit_urb (urb, GFP_ATOMIC);
if (retval)
err ("%s - usb_submit_urb failed with result %d",
__FUNCTION__, retval);
__func__, retval);
/* data interface returns incoming bytes, or we got unthrottled */
......@@ -450,12 +442,13 @@ urbs:
/* data interface wrote those outgoing bytes */
static void acm_write_bulk(struct urb *urb)
struct acm *acm = (struct acm *)urb->context;
struct acm *acm;
struct acm_wb *wb = urb->context;
dbg("Entering acm_write_bulk with status %d", urb->status);
acm = wb->instance;
acm_write_done(acm, wb);
if (ACM_READY(acm))
......@@ -489,6 +482,7 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
rv = 0;
set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
tty->driver_data = acm;
acm->tty = tty;
......@@ -556,7 +550,8 @@ static void acm_tty_unregister(struct acm *acm)
acm_table[acm->minor] = NULL;
for (i = 0; i < ACM_NW; i++)
for (i = 0; i < nr; i++)
......@@ -577,7 +572,8 @@ static void acm_tty_close(struct tty_struct *tty, struct file *filp)
if (acm->dev) {
acm_set_control(acm, acm->ctrlout = 0);
for (i = 0; i < ACM_NW; i++)
for (i = 0; i < nr; i++)
......@@ -605,7 +601,6 @@ static int acm_tty_write(struct tty_struct *tty, const unsigned char *buf, int c
spin_lock_irqsave(&acm->write_lock, flags);
if ((wbn = acm_wb_alloc(acm)) < 0) {
spin_unlock_irqrestore(&acm->write_lock, flags);
return 0;
wb = &acm->wb[wbn];
......@@ -616,7 +611,7 @@ static int acm_tty_write(struct tty_struct *tty, const unsigned char *buf, int c
wb->len = count;
spin_unlock_irqrestore(&acm->write_lock, flags);
if ((stat = acm_write_start(acm)) < 0)
if ((stat = acm_write_start(acm, wbn)) < 0)
return stat;
return count;
......@@ -809,7 +804,7 @@ static int acm_probe (struct usb_interface *intf,
struct usb_cdc_union_desc *union_header = NULL;
struct usb_cdc_country_functional_desc *cfd = NULL;
char *buffer = intf->altsetting->extra;
unsigned char *buffer = intf->altsetting->extra;
int buflen = intf->altsetting->extralen;
struct usb_interface *control_interface;
struct usb_interface *data_interface;
......@@ -886,9 +881,13 @@ static int acm_probe (struct usb_interface *intf,
if ((call_management_function & 3) != 3)
err("This device cannot do calls on its own. It is no modem.");
err("Ignoring extra header, type %d, length %d", buffer[2], buffer[0]);
/* there are LOTS more CDC descriptors that
* could legitimately be found here.
dev_dbg(&intf->dev, "Ignoring descriptor: "
"type %02x, length %d\n",