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-rw-r--r--drivers/usb/core/Makefile4
-rw-r--r--drivers/usb/core/devio.c102
-rw-r--r--drivers/usb/core/hcd.h8
-rw-r--r--drivers/usb/core/hub.c115
-rw-r--r--drivers/usb/core/hub.h7
-rw-r--r--drivers/usb/core/inode.c9
-rw-r--r--drivers/usb/core/message.c8
-rw-r--r--drivers/usb/core/urb.c26
-rw-r--r--drivers/usb/core/usb.c35
-rw-r--r--drivers/usb/core/usb.h5
10 files changed, 232 insertions, 87 deletions
diff --git a/drivers/usb/core/Makefile b/drivers/usb/core/Makefile
index 9e8c377b8161..d5503cf0bf74 100644
--- a/drivers/usb/core/Makefile
+++ b/drivers/usb/core/Makefile
@@ -3,14 +3,14 @@
#
usbcore-objs := usb.o hub.o hcd.o urb.o message.o \
- config.o file.o buffer.o sysfs.o
+ config.o file.o buffer.o sysfs.o devio.o
ifeq ($(CONFIG_PCI),y)
usbcore-objs += hcd-pci.o
endif
ifeq ($(CONFIG_USB_DEVICEFS),y)
- usbcore-objs += devio.o inode.o devices.o
+ usbcore-objs += inode.o devices.o
endif
obj-$(CONFIG_USB) += usbcore.o
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index f86bf1454e21..b4265aa7d45e 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -43,6 +43,7 @@
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usbdevice_fs.h>
+#include <linux/cdev.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
#include <linux/moduleparam.h>
@@ -50,6 +51,10 @@
#include "hcd.h" /* for usbcore internals */
#include "usb.h"
+#define USB_MAXBUS 64
+#define USB_DEVICE_MAX USB_MAXBUS * 128
+static struct class *usb_device_class;
+
struct async {
struct list_head asynclist;
struct dev_state *ps;
@@ -71,6 +76,8 @@ MODULE_PARM_DESC (usbfs_snoop, "true to log all usbfs traffic");
dev_info( dev , format , ## arg); \
} while (0)
+#define USB_DEVICE_DEV MKDEV(USB_DEVICE_MAJOR, 0)
+
#define MAX_USBFS_BUFFER_SIZE 16384
@@ -487,7 +494,7 @@ static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype, unsig
*/
static int usbdev_open(struct inode *inode, struct file *file)
{
- struct usb_device *dev;
+ struct usb_device *dev = NULL;
struct dev_state *ps;
int ret;
@@ -501,11 +508,16 @@ static int usbdev_open(struct inode *inode, struct file *file)
lock_kernel();
ret = -ENOENT;
- dev = usb_get_dev(inode->u.generic_ip);
+ /* check if we are called from a real node or usbfs */
+ if (imajor(inode) == USB_DEVICE_MAJOR)
+ dev = usbdev_lookup_minor(iminor(inode));
+ if (!dev)
+ dev = inode->u.generic_ip;
if (!dev) {
kfree(ps);
goto out;
}
+ usb_get_dev(dev);
ret = 0;
ps->dev = dev;
ps->file = file;
@@ -1226,7 +1238,6 @@ static int proc_ioctl (struct dev_state *ps, void __user *arg)
int retval = 0;
struct usb_interface *intf = NULL;
struct usb_driver *driver = NULL;
- int i;
/* get input parameters and alloc buffer */
if (copy_from_user(&ctrl, arg, sizeof (ctrl)))
@@ -1258,15 +1269,6 @@ static int proc_ioctl (struct dev_state *ps, void __user *arg)
/* disconnect kernel driver from interface */
case USBDEVFS_DISCONNECT:
- /* don't allow the user to unbind the hub driver from
- * a hub with children to manage */
- for (i = 0; i < ps->dev->maxchild; ++i) {
- if (ps->dev->children[i])
- retval = -EBUSY;
- }
- if (retval)
- break;
-
down_write(&usb_bus_type.subsys.rwsem);
if (intf->dev.driver) {
driver = to_usb_driver(intf->dev.driver);
@@ -1477,3 +1479,79 @@ struct file_operations usbfs_device_file_operations = {
.open = usbdev_open,
.release = usbdev_release,
};
+
+struct usb_device *usbdev_lookup_minor(int minor)
+{
+ struct class_device *class_dev;
+ struct usb_device *dev = NULL;
+
+ down(&usb_device_class->sem);
+ list_for_each_entry(class_dev, &usb_device_class->children, node) {
+ if (class_dev->devt == MKDEV(USB_DEVICE_MAJOR, minor)) {
+ dev = class_dev->class_data;
+ break;
+ }
+ }
+ up(&usb_device_class->sem);
+
+ return dev;
+};
+
+void usbdev_add(struct usb_device *dev)
+{
+ int minor = ((dev->bus->busnum-1) * 128) + (dev->devnum-1);
+
+ dev->class_dev = class_device_create(usb_device_class,
+ MKDEV(USB_DEVICE_MAJOR, minor), &dev->dev,
+ "usbdev%d.%d", dev->bus->busnum, dev->devnum);
+
+ dev->class_dev->class_data = dev;
+}
+
+void usbdev_remove(struct usb_device *dev)
+{
+ class_device_unregister(dev->class_dev);
+}
+
+static struct cdev usb_device_cdev = {
+ .kobj = {.name = "usb_device", },
+ .owner = THIS_MODULE,
+};
+
+int __init usbdev_init(void)
+{
+ int retval;
+
+ retval = register_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX,
+ "usb_device");
+ if (retval) {
+ err("unable to register minors for usb_device");
+ goto out;
+ }
+ cdev_init(&usb_device_cdev, &usbfs_device_file_operations);
+ retval = cdev_add(&usb_device_cdev, USB_DEVICE_DEV, USB_DEVICE_MAX);
+ if (retval) {
+ err("unable to get usb_device major %d", USB_DEVICE_MAJOR);
+ unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
+ goto out;
+ }
+ usb_device_class = class_create(THIS_MODULE, "usb_device");
+ if (IS_ERR(usb_device_class)) {
+ err("unable to register usb_device class");
+ retval = PTR_ERR(usb_device_class);
+ usb_device_class = NULL;
+ cdev_del(&usb_device_cdev);
+ unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
+ }
+
+out:
+ return retval;
+}
+
+void usbdev_cleanup(void)
+{
+ class_destroy(usb_device_class);
+ cdev_del(&usb_device_cdev);
+ unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
+}
+
diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h
index 28055f95645b..ac451fa7e4d2 100644
--- a/drivers/usb/core/hcd.h
+++ b/drivers/usb/core/hcd.h
@@ -339,11 +339,11 @@ extern int usb_check_bandwidth (struct usb_device *dev, struct urb *urb);
* to preallocate bandwidth)
*/
#define USB2_HOST_DELAY 5 /* nsec, guess */
-#define HS_NSECS(bytes) ( ((55 * 8 * 2083)/1000) \
- + ((2083UL * (3167 + BitTime (bytes)))/1000) \
+#define HS_NSECS(bytes) ( ((55 * 8 * 2083) \
+ + (2083UL * (3 + BitTime(bytes))))/1000 \
+ USB2_HOST_DELAY)
-#define HS_NSECS_ISO(bytes) ( ((38 * 8 * 2083)/1000) \
- + ((2083UL * (3167 + BitTime (bytes)))/1000) \
+#define HS_NSECS_ISO(bytes) ( ((38 * 8 * 2083) \
+ + (2083UL * (3 + BitTime(bytes))))/1000 \
+ USB2_HOST_DELAY)
#define HS_USECS(bytes) NS_TO_US (HS_NSECS(bytes))
#define HS_USECS_ISO(bytes) NS_TO_US (HS_NSECS_ISO(bytes))
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index c9412daff682..758c7f0ed159 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -492,6 +492,23 @@ static int hub_hub_status(struct usb_hub *hub,
return ret;
}
+static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
+{
+ struct usb_device *hdev = hub->hdev;
+ int ret;
+
+ if (hdev->children[port1-1] && set_state) {
+ usb_set_device_state(hdev->children[port1-1],
+ USB_STATE_NOTATTACHED);
+ }
+ ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
+ if (ret)
+ dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
+ port1, ret);
+
+ return ret;
+}
+
static int hub_configure(struct usb_hub *hub,
struct usb_endpoint_descriptor *endpoint)
{
@@ -610,19 +627,33 @@ static int hub_configure(struct usb_hub *hub,
break;
}
+ /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
- case 0x00:
- if (hdev->descriptor.bDeviceProtocol != 0)
- dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
+ case HUB_TTTT_8_BITS:
+ if (hdev->descriptor.bDeviceProtocol != 0) {
+ hub->tt.think_time = 666;
+ dev_dbg(hub_dev, "TT requires at most %d "
+ "FS bit times (%d ns)\n",
+ 8, hub->tt.think_time);
+ }
break;
- case 0x20:
- dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
+ case HUB_TTTT_16_BITS:
+ hub->tt.think_time = 666 * 2;
+ dev_dbg(hub_dev, "TT requires at most %d "
+ "FS bit times (%d ns)\n",
+ 16, hub->tt.think_time);
break;
- case 0x40:
- dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
+ case HUB_TTTT_24_BITS:
+ hub->tt.think_time = 666 * 3;
+ dev_dbg(hub_dev, "TT requires at most %d "
+ "FS bit times (%d ns)\n",
+ 24, hub->tt.think_time);
break;
- case 0x60:
- dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
+ case HUB_TTTT_32_BITS:
+ hub->tt.think_time = 666 * 4;
+ dev_dbg(hub_dev, "TT requires at most %d "
+ "FS bit times (%d ns)\n",
+ 32, hub->tt.think_time);
break;
}
@@ -712,20 +743,36 @@ fail:
static unsigned highspeed_hubs;
+/* Called after the hub driver is unbound from a hub with children */
+static void hub_remove_children_work(void *__hub)
+{
+ struct usb_hub *hub = __hub;
+ struct usb_device *hdev = hub->hdev;
+ int i;
+
+ kfree(hub);
+
+ usb_lock_device(hdev);
+ for (i = 0; i < hdev->maxchild; ++i) {
+ if (hdev->children[i])
+ usb_disconnect(&hdev->children[i]);
+ }
+ usb_unlock_device(hdev);
+ usb_put_dev(hdev);
+}
+
static void hub_disconnect(struct usb_interface *intf)
{
struct usb_hub *hub = usb_get_intfdata (intf);
struct usb_device *hdev;
+ int n, port1;
- if (!hub)
- return;
+ usb_set_intfdata (intf, NULL);
hdev = hub->hdev;
if (hdev->speed == USB_SPEED_HIGH)
highspeed_hubs--;
- usb_set_intfdata (intf, NULL);
-
hub_quiesce(hub);
usb_free_urb(hub->urb);
hub->urb = NULL;
@@ -746,8 +793,27 @@ static void hub_disconnect(struct usb_interface *intf)
hub->buffer = NULL;
}
- /* Free the memory */
- kfree(hub);
+ /* If there are any children then this is an unbind only, not a
+ * physical disconnection. The active ports must be disabled
+ * and later on we must call usb_disconnect(). We can't call
+ * it now because we may not hold the hub's device lock.
+ */
+ n = 0;
+ for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
+ if (hdev->children[port1 - 1]) {
+ ++n;
+ hub_port_disable(hub, port1, 1);
+ }
+ }
+
+ if (n == 0)
+ kfree(hub);
+ else {
+ /* Reuse the hub->leds work_struct for our own purposes */
+ INIT_WORK(&hub->leds, hub_remove_children_work, hub);
+ schedule_work(&hub->leds);
+ usb_get_dev(hdev);
+ }
}
static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
@@ -1051,6 +1117,7 @@ void usb_disconnect(struct usb_device **pdev)
dev_dbg (&udev->dev, "unregistering device\n");
release_address(udev);
usbfs_remove_device(udev);
+ usbdev_remove(udev);
usb_remove_sysfs_dev_files(udev);
/* Avoid races with recursively_mark_NOTATTACHED() */
@@ -1290,6 +1357,7 @@ int usb_new_device(struct usb_device *udev)
/* USB device state == configured ... usable */
/* add a /proc/bus/usb entry */
+ usbdev_add(udev);
usbfs_add_device(udev);
return 0;
@@ -1428,23 +1496,6 @@ static int hub_port_reset(struct usb_hub *hub, int port1,
return status;
}
-static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
-{
- struct usb_device *hdev = hub->hdev;
- int ret;
-
- if (hdev->children[port1-1] && set_state) {
- usb_set_device_state(hdev->children[port1-1],
- USB_STATE_NOTATTACHED);
- }
- ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
- if (ret)
- dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
- port1, ret);
-
- return ret;
-}
-
/*
* Disable a port and mark a logical connnect-change event, so that some
* time later khubd will disconnect() any existing usb_device on the port
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 53bf5649621e..e7fa9b5a521e 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -157,6 +157,12 @@ enum hub_led_mode {
struct usb_device;
+/* Transaction Translator Think Times, in bits */
+#define HUB_TTTT_8_BITS 0x00
+#define HUB_TTTT_16_BITS 0x20
+#define HUB_TTTT_24_BITS 0x40
+#define HUB_TTTT_32_BITS 0x60
+
/*
* As of USB 2.0, full/low speed devices are segregated into trees.
* One type grows from USB 1.1 host controllers (OHCI, UHCI etc).
@@ -170,6 +176,7 @@ struct usb_device;
struct usb_tt {
struct usb_device *hub; /* upstream highspeed hub */
int multi; /* true means one TT per port */
+ unsigned think_time; /* think time in ns */
/* for control/bulk error recovery (CLEAR_TT_BUFFER) */
spinlock_t lock;
diff --git a/drivers/usb/core/inode.c b/drivers/usb/core/inode.c
index c3e3a95d3804..640f41e47029 100644
--- a/drivers/usb/core/inode.c
+++ b/drivers/usb/core/inode.c
@@ -728,15 +728,9 @@ int __init usbfs_init(void)
{
int retval;
- retval = usb_register(&usbfs_driver);
- if (retval)
- return retval;
-
retval = register_filesystem(&usb_fs_type);
- if (retval) {
- usb_deregister(&usbfs_driver);
+ if (retval)
return retval;
- }
/* create mount point for usbfs */
usbdir = proc_mkdir("usb", proc_bus);
@@ -746,7 +740,6 @@ int __init usbfs_init(void)
void usbfs_cleanup(void)
{
- usb_deregister(&usbfs_driver);
unregister_filesystem(&usb_fs_type);
if (usbdir)
remove_proc_entry("usb", proc_bus);
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 88d1b376f67c..c47c8052b486 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -48,7 +48,6 @@ static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length)
init_completion(&done);
urb->context = &done;
- urb->transfer_flags |= URB_ASYNC_UNLINK;
urb->actual_length = 0;
status = usb_submit_urb(urb, GFP_NOIO);
@@ -266,7 +265,9 @@ static void sg_complete (struct urb *urb, struct pt_regs *regs)
continue;
if (found) {
status = usb_unlink_urb (io->urbs [i]);
- if (status != -EINPROGRESS && status != -EBUSY)
+ if (status != -EINPROGRESS
+ && status != -ENODEV
+ && status != -EBUSY)
dev_err (&io->dev->dev,
"%s, unlink --> %d\n",
__FUNCTION__, status);
@@ -357,8 +358,7 @@ int usb_sg_init (
if (!io->urbs)
goto nomem;
- urb_flags = URB_ASYNC_UNLINK | URB_NO_TRANSFER_DMA_MAP
- | URB_NO_INTERRUPT;
+ urb_flags = URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT;
if (usb_pipein (pipe))
urb_flags |= URB_SHORT_NOT_OK;
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index c0feee25ff0a..c846fefb7386 100644
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -309,9 +309,8 @@ int usb_submit_urb(struct urb *urb, unsigned mem_flags)
unsigned int allowed;
/* enforce simple/standard policy */
- allowed = URB_ASYNC_UNLINK; // affects later unlinks
- allowed |= (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP);
- allowed |= URB_NO_INTERRUPT;
+ allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP |
+ URB_NO_INTERRUPT);
switch (temp) {
case PIPE_BULK:
if (is_out)
@@ -400,14 +399,8 @@ int usb_submit_urb(struct urb *urb, unsigned mem_flags)
* canceled (rather than any other code) and will quickly be removed
* from host controller data structures.
*
- * In the past, clearing the URB_ASYNC_UNLINK transfer flag for the
- * URB indicated that the request was synchronous. This usage is now
- * deprecated; if the flag is clear the call will be forwarded to
- * usb_kill_urb() and the return value will be 0. In the future, drivers
- * should call usb_kill_urb() directly for synchronous unlinking.
- *
- * When the URB_ASYNC_UNLINK transfer flag for the URB is set, this
- * request is asynchronous. Success is indicated by returning -EINPROGRESS,
+ * This request is always asynchronous.
+ * Success is indicated by returning -EINPROGRESS,
* at which time the URB will normally have been unlinked but not yet
* given back to the device driver. When it is called, the completion
* function will see urb->status == -ECONNRESET. Failure is indicated
@@ -453,17 +446,6 @@ int usb_unlink_urb(struct urb *urb)
{
if (!urb)
return -EINVAL;
- if (!(urb->transfer_flags & URB_ASYNC_UNLINK)) {
-#ifdef CONFIG_DEBUG_KERNEL
- if (printk_ratelimit()) {
- printk(KERN_NOTICE "usb_unlink_urb() is deprecated for "
- "synchronous unlinks. Use usb_kill_urb() instead.\n");
- WARN_ON(1);
- }
-#endif
- usb_kill_urb(urb);
- return 0;
- }
if (!(urb->dev && urb->dev->bus && urb->dev->bus->op))
return -ENODEV;
return urb->dev->bus->op->unlink_urb(urb, -ECONNRESET);
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 2cddd8a00437..087af73a59dd 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -65,6 +65,16 @@ static int generic_probe (struct device *dev)
}
static int generic_remove (struct device *dev)
{
+ struct usb_device *udev = to_usb_device(dev);
+
+ /* if this is only an unbind, not a physical disconnect, then
+ * unconfigure the device */
+ if (udev->state == USB_STATE_CONFIGURED)
+ usb_set_configuration(udev, 0);
+
+ /* in case the call failed or the device was suspended */
+ if (udev->state >= USB_STATE_CONFIGURED)
+ usb_disable_device(udev, 0);
return 0;
}
@@ -912,7 +922,7 @@ int usb_trylock_device(struct usb_device *udev)
* is neither BINDING nor BOUND. Rather than sleeping to wait for the
* lock, the routine polls repeatedly. This is to prevent deadlock with
* disconnect; in some drivers (such as usb-storage) the disconnect()
- * callback will block waiting for a device reset to complete.
+ * or suspend() method will block waiting for a device reset to complete.
*
* Returns a negative error code for failure, otherwise 1 or 0 to indicate
* that the device will or will not have to be unlocked. (0 can be
@@ -922,6 +932,8 @@ int usb_trylock_device(struct usb_device *udev)
int usb_lock_device_for_reset(struct usb_device *udev,
struct usb_interface *iface)
{
+ unsigned long jiffies_expire = jiffies + HZ;
+
if (udev->state == USB_STATE_NOTATTACHED)
return -ENODEV;
if (udev->state == USB_STATE_SUSPENDED)
@@ -938,6 +950,12 @@ int usb_lock_device_for_reset(struct usb_device *udev,
}
while (!usb_trylock_device(udev)) {
+
+ /* If we can't acquire the lock after waiting one second,
+ * we're probably deadlocked */
+ if (time_after(jiffies, jiffies_expire))
+ return -EBUSY;
+
msleep(15);
if (udev->state == USB_STATE_NOTATTACHED)
return -ENODEV;
@@ -1478,13 +1496,18 @@ static int __init usb_init(void)
retval = usb_major_init();
if (retval)
goto major_init_failed;
+ retval = usb_register(&usbfs_driver);
+ if (retval)
+ goto driver_register_failed;
+ retval = usbdev_init();
+ if (retval)
+ goto usbdevice_init_failed;
retval = usbfs_init();
if (retval)
goto fs_init_failed;
retval = usb_hub_init();
if (retval)
goto hub_init_failed;
-
retval = driver_register(&usb_generic_driver);
if (!retval)
goto out;
@@ -1493,7 +1516,11 @@ static int __init usb_init(void)
hub_init_failed:
usbfs_cleanup();
fs_init_failed:
- usb_major_cleanup();
+ usbdev_cleanup();
+usbdevice_init_failed:
+ usb_deregister(&usbfs_driver);
+driver_register_failed:
+ usb_major_cleanup();
major_init_failed:
usb_host_cleanup();
host_init_failed:
@@ -1514,6 +1541,8 @@ static void __exit usb_exit(void)
driver_unregister(&usb_generic_driver);
usb_major_cleanup();
usbfs_cleanup();
+ usb_deregister(&usbfs_driver);
+ usbdev_cleanup();
usb_hub_cleanup();
usb_host_cleanup();
bus_unregister(&usb_bus_type);
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index 2c690f6d4c18..83d48c8133af 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -37,6 +37,11 @@ extern struct file_operations usbfs_devices_fops;
extern struct file_operations usbfs_device_file_operations;
extern void usbfs_conn_disc_event(void);
+extern int usbdev_init(void);
+extern void usbdev_cleanup(void);
+extern void usbdev_add(struct usb_device *dev);
+extern void usbdev_remove(struct usb_device *dev);
+extern struct usb_device *usbdev_lookup_minor(int minor);
struct dev_state {
struct list_head list; /* state list */