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path: root/drivers/usb/core/hub.c
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Diffstat (limited to 'drivers/usb/core/hub.c')
-rw-r--r--drivers/usb/core/hub.c3057
1 files changed, 3057 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
new file mode 100644
index 000000000000..fa0dc4f6de47
--- /dev/null
+++ b/drivers/usb/core/hub.c
@@ -0,0 +1,3057 @@
+/*
+ * USB hub driver.
+ *
+ * (C) Copyright 1999 Linus Torvalds
+ * (C) Copyright 1999 Johannes Erdfelt
+ * (C) Copyright 1999 Gregory P. Smith
+ * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
+ *
+ */
+
+#include <linux/config.h>
+#ifdef CONFIG_USB_DEBUG
+ #define DEBUG
+#else
+ #undef DEBUG
+#endif
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/completion.h>
+#include <linux/sched.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/ioctl.h>
+#include <linux/usb.h>
+#include <linux/usbdevice_fs.h>
+
+#include <asm/semaphore.h>
+#include <asm/uaccess.h>
+#include <asm/byteorder.h>
+
+#include "usb.h"
+#include "hcd.h"
+#include "hub.h"
+
+/* Protect struct usb_device->state and ->children members
+ * Note: Both are also protected by ->serialize, except that ->state can
+ * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
+static DEFINE_SPINLOCK(device_state_lock);
+
+/* khubd's worklist and its lock */
+static DEFINE_SPINLOCK(hub_event_lock);
+static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
+
+/* Wakes up khubd */
+static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
+
+static pid_t khubd_pid = 0; /* PID of khubd */
+static DECLARE_COMPLETION(khubd_exited);
+
+/* cycle leds on hubs that aren't blinking for attention */
+static int blinkenlights = 0;
+module_param (blinkenlights, bool, S_IRUGO);
+MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
+
+/*
+ * As of 2.6.10 we introduce a new USB device initialization scheme which
+ * closely resembles the way Windows works. Hopefully it will be compatible
+ * with a wider range of devices than the old scheme. However some previously
+ * working devices may start giving rise to "device not accepting address"
+ * errors; if that happens the user can try the old scheme by adjusting the
+ * following module parameters.
+ *
+ * For maximum flexibility there are two boolean parameters to control the
+ * hub driver's behavior. On the first initialization attempt, if the
+ * "old_scheme_first" parameter is set then the old scheme will be used,
+ * otherwise the new scheme is used. If that fails and "use_both_schemes"
+ * is set, then the driver will make another attempt, using the other scheme.
+ */
+static int old_scheme_first = 0;
+module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(old_scheme_first,
+ "start with the old device initialization scheme");
+
+static int use_both_schemes = 1;
+module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(use_both_schemes,
+ "try the other device initialization scheme if the "
+ "first one fails");
+
+
+#ifdef DEBUG
+static inline char *portspeed (int portstatus)
+{
+ if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
+ return "480 Mb/s";
+ else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
+ return "1.5 Mb/s";
+ else
+ return "12 Mb/s";
+}
+#endif
+
+/* Note that hdev or one of its children must be locked! */
+static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
+{
+ return usb_get_intfdata(hdev->actconfig->interface[0]);
+}
+
+/* USB 2.0 spec Section 11.24.4.5 */
+static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
+{
+ int i, ret;
+
+ for (i = 0; i < 3; i++) {
+ ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+ USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
+ USB_DT_HUB << 8, 0, data, size,
+ USB_CTRL_GET_TIMEOUT);
+ if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
+ return ret;
+ }
+ return -EINVAL;
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.1
+ */
+static int clear_hub_feature(struct usb_device *hdev, int feature)
+{
+ return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+ USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.2
+ */
+static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
+{
+ return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+ USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
+ NULL, 0, 1000);
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.13
+ */
+static int set_port_feature(struct usb_device *hdev, int port1, int feature)
+{
+ return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+ USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
+ NULL, 0, 1000);
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
+ * for info about using port indicators
+ */
+static void set_port_led(
+ struct usb_hub *hub,
+ int port1,
+ int selector
+)
+{
+ int status = set_port_feature(hub->hdev, (selector << 8) | port1,
+ USB_PORT_FEAT_INDICATOR);
+ if (status < 0)
+ dev_dbg (hub->intfdev,
+ "port %d indicator %s status %d\n",
+ port1,
+ ({ char *s; switch (selector) {
+ case HUB_LED_AMBER: s = "amber"; break;
+ case HUB_LED_GREEN: s = "green"; break;
+ case HUB_LED_OFF: s = "off"; break;
+ case HUB_LED_AUTO: s = "auto"; break;
+ default: s = "??"; break;
+ }; s; }),
+ status);
+}
+
+#define LED_CYCLE_PERIOD ((2*HZ)/3)
+
+static void led_work (void *__hub)
+{
+ struct usb_hub *hub = __hub;
+ struct usb_device *hdev = hub->hdev;
+ unsigned i;
+ unsigned changed = 0;
+ int cursor = -1;
+
+ if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
+ return;
+
+ for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
+ unsigned selector, mode;
+
+ /* 30%-50% duty cycle */
+
+ switch (hub->indicator[i]) {
+ /* cycle marker */
+ case INDICATOR_CYCLE:
+ cursor = i;
+ selector = HUB_LED_AUTO;
+ mode = INDICATOR_AUTO;
+ break;
+ /* blinking green = sw attention */
+ case INDICATOR_GREEN_BLINK:
+ selector = HUB_LED_GREEN;
+ mode = INDICATOR_GREEN_BLINK_OFF;
+ break;
+ case INDICATOR_GREEN_BLINK_OFF:
+ selector = HUB_LED_OFF;
+ mode = INDICATOR_GREEN_BLINK;
+ break;
+ /* blinking amber = hw attention */
+ case INDICATOR_AMBER_BLINK:
+ selector = HUB_LED_AMBER;
+ mode = INDICATOR_AMBER_BLINK_OFF;
+ break;
+ case INDICATOR_AMBER_BLINK_OFF:
+ selector = HUB_LED_OFF;
+ mode = INDICATOR_AMBER_BLINK;
+ break;
+ /* blink green/amber = reserved */
+ case INDICATOR_ALT_BLINK:
+ selector = HUB_LED_GREEN;
+ mode = INDICATOR_ALT_BLINK_OFF;
+ break;
+ case INDICATOR_ALT_BLINK_OFF:
+ selector = HUB_LED_AMBER;
+ mode = INDICATOR_ALT_BLINK;
+ break;
+ default:
+ continue;
+ }
+ if (selector != HUB_LED_AUTO)
+ changed = 1;
+ set_port_led(hub, i + 1, selector);
+ hub->indicator[i] = mode;
+ }
+ if (!changed && blinkenlights) {
+ cursor++;
+ cursor %= hub->descriptor->bNbrPorts;
+ set_port_led(hub, cursor + 1, HUB_LED_GREEN);
+ hub->indicator[cursor] = INDICATOR_CYCLE;
+ changed++;
+ }
+ if (changed)
+ schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
+}
+
+/* use a short timeout for hub/port status fetches */
+#define USB_STS_TIMEOUT 1000
+#define USB_STS_RETRIES 5
+
+/*
+ * USB 2.0 spec Section 11.24.2.6
+ */
+static int get_hub_status(struct usb_device *hdev,
+ struct usb_hub_status *data)
+{
+ int i, status = -ETIMEDOUT;
+
+ for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
+ status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+ USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
+ data, sizeof(*data), USB_STS_TIMEOUT);
+ }
+ return status;
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.7
+ */
+static int get_port_status(struct usb_device *hdev, int port1,
+ struct usb_port_status *data)
+{
+ int i, status = -ETIMEDOUT;
+
+ for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
+ status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+ USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
+ data, sizeof(*data), USB_STS_TIMEOUT);
+ }
+ return status;
+}
+
+static void kick_khubd(struct usb_hub *hub)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&hub_event_lock, flags);
+ if (list_empty(&hub->event_list)) {
+ list_add_tail(&hub->event_list, &hub_event_list);
+ wake_up(&khubd_wait);
+ }
+ spin_unlock_irqrestore(&hub_event_lock, flags);
+}
+
+void usb_kick_khubd(struct usb_device *hdev)
+{
+ kick_khubd(hdev_to_hub(hdev));
+}
+
+
+/* completion function, fires on port status changes and various faults */
+static void hub_irq(struct urb *urb, struct pt_regs *regs)
+{
+ struct usb_hub *hub = (struct usb_hub *)urb->context;
+ int status;
+ int i;
+ unsigned long bits;
+
+ switch (urb->status) {
+ case -ENOENT: /* synchronous unlink */
+ case -ECONNRESET: /* async unlink */
+ case -ESHUTDOWN: /* hardware going away */
+ return;
+
+ default: /* presumably an error */
+ /* Cause a hub reset after 10 consecutive errors */
+ dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
+ if ((++hub->nerrors < 10) || hub->error)
+ goto resubmit;
+ hub->error = urb->status;
+ /* FALL THROUGH */
+
+ /* let khubd handle things */
+ case 0: /* we got data: port status changed */
+ bits = 0;
+ for (i = 0; i < urb->actual_length; ++i)
+ bits |= ((unsigned long) ((*hub->buffer)[i]))
+ << (i*8);
+ hub->event_bits[0] = bits;
+ break;
+ }
+
+ hub->nerrors = 0;
+
+ /* Something happened, let khubd figure it out */
+ kick_khubd(hub);
+
+resubmit:
+ if (hub->quiescing)
+ return;
+
+ if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
+ && status != -ENODEV && status != -EPERM)
+ dev_err (hub->intfdev, "resubmit --> %d\n", status);
+}
+
+/* USB 2.0 spec Section 11.24.2.3 */
+static inline int
+hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
+{
+ return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+ HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
+ tt, NULL, 0, 1000);
+}
+
+/*
+ * enumeration blocks khubd for a long time. we use keventd instead, since
+ * long blocking there is the exception, not the rule. accordingly, HCDs
+ * talking to TTs must queue control transfers (not just bulk and iso), so
+ * both can talk to the same hub concurrently.
+ */
+static void hub_tt_kevent (void *arg)
+{
+ struct usb_hub *hub = arg;
+ unsigned long flags;
+
+ spin_lock_irqsave (&hub->tt.lock, flags);
+ while (!list_empty (&hub->tt.clear_list)) {
+ struct list_head *temp;
+ struct usb_tt_clear *clear;
+ struct usb_device *hdev = hub->hdev;
+ int status;
+
+ temp = hub->tt.clear_list.next;
+ clear = list_entry (temp, struct usb_tt_clear, clear_list);
+ list_del (&clear->clear_list);
+
+ /* drop lock so HCD can concurrently report other TT errors */
+ spin_unlock_irqrestore (&hub->tt.lock, flags);
+ status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
+ spin_lock_irqsave (&hub->tt.lock, flags);
+
+ if (status)
+ dev_err (&hdev->dev,
+ "clear tt %d (%04x) error %d\n",
+ clear->tt, clear->devinfo, status);
+ kfree (clear);
+ }
+ spin_unlock_irqrestore (&hub->tt.lock, flags);
+}
+
+/**
+ * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
+ * @udev: the device whose split transaction failed
+ * @pipe: identifies the endpoint of the failed transaction
+ *
+ * High speed HCDs use this to tell the hub driver that some split control or
+ * bulk transaction failed in a way that requires clearing internal state of
+ * a transaction translator. This is normally detected (and reported) from
+ * interrupt context.
+ *
+ * It may not be possible for that hub to handle additional full (or low)
+ * speed transactions until that state is fully cleared out.
+ */
+void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
+{
+ struct usb_tt *tt = udev->tt;
+ unsigned long flags;
+ struct usb_tt_clear *clear;
+
+ /* we've got to cope with an arbitrary number of pending TT clears,
+ * since each TT has "at least two" buffers that can need it (and
+ * there can be many TTs per hub). even if they're uncommon.
+ */
+ if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
+ dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
+ /* FIXME recover somehow ... RESET_TT? */
+ return;
+ }
+
+ /* info that CLEAR_TT_BUFFER needs */
+ clear->tt = tt->multi ? udev->ttport : 1;
+ clear->devinfo = usb_pipeendpoint (pipe);
+ clear->devinfo |= udev->devnum << 4;
+ clear->devinfo |= usb_pipecontrol (pipe)
+ ? (USB_ENDPOINT_XFER_CONTROL << 11)
+ : (USB_ENDPOINT_XFER_BULK << 11);
+ if (usb_pipein (pipe))
+ clear->devinfo |= 1 << 15;
+
+ /* tell keventd to clear state for this TT */
+ spin_lock_irqsave (&tt->lock, flags);
+ list_add_tail (&clear->clear_list, &tt->clear_list);
+ schedule_work (&tt->kevent);
+ spin_unlock_irqrestore (&tt->lock, flags);
+}
+
+static void hub_power_on(struct usb_hub *hub)
+{
+ int port1;
+
+ /* if hub supports power switching, enable power on each port */
+ if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
+ dev_dbg(hub->intfdev, "enabling power on all ports\n");
+ for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
+ set_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_POWER);
+ }
+
+ /* Wait for power to be enabled */
+ msleep(hub->descriptor->bPwrOn2PwrGood * 2);
+}
+
+static void hub_quiesce(struct usb_hub *hub)
+{
+ /* stop khubd and related activity */
+ hub->quiescing = 1;
+ usb_kill_urb(hub->urb);
+ if (hub->has_indicators)
+ cancel_delayed_work(&hub->leds);
+ if (hub->has_indicators || hub->tt.hub)
+ flush_scheduled_work();
+}
+
+static void hub_activate(struct usb_hub *hub)
+{
+ int status;
+
+ hub->quiescing = 0;
+ hub->activating = 1;
+ status = usb_submit_urb(hub->urb, GFP_NOIO);
+ if (status < 0)
+ dev_err(hub->intfdev, "activate --> %d\n", status);
+ if (hub->has_indicators && blinkenlights)
+ schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
+
+ /* scan all ports ASAP */
+ kick_khubd(hub);
+}
+
+static int hub_hub_status(struct usb_hub *hub,
+ u16 *status, u16 *change)
+{
+ int ret;
+
+ ret = get_hub_status(hub->hdev, &hub->status->hub);
+ if (ret < 0)
+ dev_err (hub->intfdev,
+ "%s failed (err = %d)\n", __FUNCTION__, ret);
+ else {
+ *status = le16_to_cpu(hub->status->hub.wHubStatus);
+ *change = le16_to_cpu(hub->status->hub.wHubChange);
+ ret = 0;
+ }
+ return ret;
+}
+
+static int hub_configure(struct usb_hub *hub,
+ struct usb_endpoint_descriptor *endpoint)
+{
+ struct usb_device *hdev = hub->hdev;
+ struct device *hub_dev = hub->intfdev;
+ u16 hubstatus, hubchange;
+ unsigned int pipe;
+ int maxp, ret;
+ char *message;
+
+ hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
+ &hub->buffer_dma);
+ if (!hub->buffer) {
+ message = "can't allocate hub irq buffer";
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
+ if (!hub->status) {
+ message = "can't kmalloc hub status buffer";
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
+ if (!hub->descriptor) {
+ message = "can't kmalloc hub descriptor";
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ /* Request the entire hub descriptor.
+ * hub->descriptor can handle USB_MAXCHILDREN ports,
+ * but the hub can/will return fewer bytes here.
+ */
+ ret = get_hub_descriptor(hdev, hub->descriptor,
+ sizeof(*hub->descriptor));
+ if (ret < 0) {
+ message = "can't read hub descriptor";
+ goto fail;
+ } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
+ message = "hub has too many ports!";
+ ret = -ENODEV;
+ goto fail;
+ }
+
+ hdev->maxchild = hub->descriptor->bNbrPorts;
+ dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
+ (hdev->maxchild == 1) ? "" : "s");
+
+ le16_to_cpus(&hub->descriptor->wHubCharacteristics);
+
+ if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
+ int i;
+ char portstr [USB_MAXCHILDREN + 1];
+
+ for (i = 0; i < hdev->maxchild; i++)
+ portstr[i] = hub->descriptor->DeviceRemovable
+ [((i + 1) / 8)] & (1 << ((i + 1) % 8))
+ ? 'F' : 'R';
+ portstr[hdev->maxchild] = 0;
+ dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
+ } else
+ dev_dbg(hub_dev, "standalone hub\n");
+
+ switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
+ case 0x00:
+ dev_dbg(hub_dev, "ganged power switching\n");
+ break;
+ case 0x01:
+ dev_dbg(hub_dev, "individual port power switching\n");
+ break;
+ case 0x02:
+ case 0x03:
+ dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
+ break;
+ }
+
+ switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
+ case 0x00:
+ dev_dbg(hub_dev, "global over-current protection\n");
+ break;
+ case 0x08:
+ dev_dbg(hub_dev, "individual port over-current protection\n");
+ break;
+ case 0x10:
+ case 0x18:
+ dev_dbg(hub_dev, "no over-current protection\n");
+ break;
+ }
+
+ spin_lock_init (&hub->tt.lock);
+ INIT_LIST_HEAD (&hub->tt.clear_list);
+ INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
+ switch (hdev->descriptor.bDeviceProtocol) {
+ case 0:
+ break;
+ case 1:
+ dev_dbg(hub_dev, "Single TT\n");
+ hub->tt.hub = hdev;
+ break;
+ case 2:
+ ret = usb_set_interface(hdev, 0, 1);
+ if (ret == 0) {
+ dev_dbg(hub_dev, "TT per port\n");
+ hub->tt.multi = 1;
+ } else
+ dev_err(hub_dev, "Using single TT (err %d)\n",
+ ret);
+ hub->tt.hub = hdev;
+ break;
+ default:
+ dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
+ hdev->descriptor.bDeviceProtocol);
+ break;
+ }
+
+ 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");
+ break;
+ case 0x20:
+ dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
+ break;
+ case 0x40:
+ dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
+ break;
+ case 0x60:
+ dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
+ break;
+ }
+
+ /* probe() zeroes hub->indicator[] */
+ if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
+ hub->has_indicators = 1;
+ dev_dbg(hub_dev, "Port indicators are supported\n");
+ }
+
+ dev_dbg(hub_dev, "power on to power good time: %dms\n",
+ hub->descriptor->bPwrOn2PwrGood * 2);
+
+ /* power budgeting mostly matters with bus-powered hubs,
+ * and battery-powered root hubs (may provide just 8 mA).
+ */
+ ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
+ if (ret < 0) {
+ message = "can't get hub status";
+ goto fail;
+ }
+ cpu_to_le16s(&hubstatus);
+ if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
+ dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
+ hub->descriptor->bHubContrCurrent);
+ hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
+ / 2;
+ dev_dbg(hub_dev, "%dmA bus power budget for children\n",
+ hub->power_budget * 2);
+ }
+
+
+ ret = hub_hub_status(hub, &hubstatus, &hubchange);
+ if (ret < 0) {
+ message = "can't get hub status";
+ goto fail;
+ }
+
+ /* local power status reports aren't always correct */
+ if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
+ dev_dbg(hub_dev, "local power source is %s\n",
+ (hubstatus & HUB_STATUS_LOCAL_POWER)
+ ? "lost (inactive)" : "good");
+
+ if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
+ dev_dbg(hub_dev, "%sover-current condition exists\n",
+ (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
+
+ /* set up the interrupt endpoint */
+ pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
+ maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
+
+ if (maxp > sizeof(*hub->buffer))
+ maxp = sizeof(*hub->buffer);
+
+ hub->urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!hub->urb) {
+ message = "couldn't allocate interrupt urb";
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
+ hub, endpoint->bInterval);
+ hub->urb->transfer_dma = hub->buffer_dma;
+ hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+ /* maybe cycle the hub leds */
+ if (hub->has_indicators && blinkenlights)
+ hub->indicator [0] = INDICATOR_CYCLE;
+
+ hub_power_on(hub);
+ hub_activate(hub);
+ return 0;
+
+fail:
+ dev_err (hub_dev, "config failed, %s (err %d)\n",
+ message, ret);
+ /* hub_disconnect() frees urb and descriptor */
+ return ret;
+}
+
+static unsigned highspeed_hubs;
+
+static void hub_disconnect(struct usb_interface *intf)
+{
+ struct usb_hub *hub = usb_get_intfdata (intf);
+ struct usb_device *hdev;
+
+ if (!hub)
+ return;
+ 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;
+
+ spin_lock_irq(&hub_event_lock);
+ list_del_init(&hub->event_list);
+ spin_unlock_irq(&hub_event_lock);
+
+ if (hub->descriptor) {
+ kfree(hub->descriptor);
+ hub->descriptor = NULL;
+ }
+
+ if (hub->status) {
+ kfree(hub->status);
+ hub->status = NULL;
+ }
+
+ if (hub->buffer) {
+ usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
+ hub->buffer_dma);
+ hub->buffer = NULL;
+ }
+
+ /* Free the memory */
+ kfree(hub);
+}
+
+static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
+{
+ struct usb_host_interface *desc;
+ struct usb_endpoint_descriptor *endpoint;
+ struct usb_device *hdev;
+ struct usb_hub *hub;
+
+ desc = intf->cur_altsetting;
+ hdev = interface_to_usbdev(intf);
+
+ /* Some hubs have a subclass of 1, which AFAICT according to the */
+ /* specs is not defined, but it works */
+ if ((desc->desc.bInterfaceSubClass != 0) &&
+ (desc->desc.bInterfaceSubClass != 1)) {
+descriptor_error:
+ dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
+ return -EIO;
+ }
+
+ /* Multiple endpoints? What kind of mutant ninja-hub is this? */
+ if (desc->desc.bNumEndpoints != 1)
+ goto descriptor_error;
+
+ endpoint = &desc->endpoint[0].desc;
+
+ /* Output endpoint? Curiouser and curiouser.. */
+ if (!(endpoint->bEndpointAddress & USB_DIR_IN))
+ goto descriptor_error;
+
+ /* If it's not an interrupt endpoint, we'd better punt! */
+ if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
+ != USB_ENDPOINT_XFER_INT)
+ goto descriptor_error;
+
+ /* We found a hub */
+ dev_info (&intf->dev, "USB hub found\n");
+
+ hub = kmalloc(sizeof(*hub), GFP_KERNEL);
+ if (!hub) {
+ dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
+ return -ENOMEM;
+ }
+
+ memset(hub, 0, sizeof(*hub));
+
+ INIT_LIST_HEAD(&hub->event_list);
+ hub->intfdev = &intf->dev;
+ hub->hdev = hdev;
+ INIT_WORK(&hub->leds, led_work, hub);
+
+ usb_set_intfdata (intf, hub);
+
+ if (hdev->speed == USB_SPEED_HIGH)
+ highspeed_hubs++;
+
+ if (hub_configure(hub, endpoint) >= 0)
+ return 0;
+
+ hub_disconnect (intf);
+ return -ENODEV;
+}
+
+static int
+hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
+{
+ struct usb_device *hdev = interface_to_usbdev (intf);
+
+ /* assert ifno == 0 (part of hub spec) */
+ switch (code) {
+ case USBDEVFS_HUB_PORTINFO: {
+ struct usbdevfs_hub_portinfo *info = user_data;
+ int i;
+
+ spin_lock_irq(&device_state_lock);
+ if (hdev->devnum <= 0)
+ info->nports = 0;
+ else {
+ info->nports = hdev->maxchild;
+ for (i = 0; i < info->nports; i++) {
+ if (hdev->children[i] == NULL)
+ info->port[i] = 0;
+ else
+ info->port[i] =
+ hdev->children[i]->devnum;
+ }
+ }
+ spin_unlock_irq(&device_state_lock);
+
+ return info->nports + 1;
+ }
+
+ default:
+ return -ENOSYS;
+ }
+}
+
+/* caller has locked the hub device */
+static void hub_pre_reset(struct usb_hub *hub)
+{
+ struct usb_device *hdev = hub->hdev;
+ int i;
+
+ for (i = 0; i < hdev->maxchild; ++i) {
+ if (hdev->children[i])
+ usb_disconnect(&hdev->children[i]);
+ }
+ hub_quiesce(hub);
+}
+
+/* caller has locked the hub device */
+static void hub_post_reset(struct usb_hub *hub)
+{
+ hub_activate(hub);
+ hub_power_on(hub);
+}
+
+
+/* grab device/port lock, returning index of that port (zero based).
+ * protects the upstream link used by this device from concurrent
+ * tree operations like suspend, resume, reset, and disconnect, which
+ * apply to everything downstream of a given port.
+ */
+static int locktree(struct usb_device *udev)
+{
+ int t;
+ struct usb_device *hdev;
+
+ if (!udev)
+ return -ENODEV;
+
+ /* root hub is always the first lock in the series */
+ hdev = udev->parent;
+ if (!hdev) {
+ usb_lock_device(udev);
+ return 0;
+ }
+
+ /* on the path from root to us, lock everything from
+ * top down, dropping parent locks when not needed
+ */
+ t = locktree(hdev);
+ if (t < 0)
+ return t;
+ for (t = 0; t < hdev->maxchild; t++) {
+ if (hdev->children[t] == udev) {
+ /* everything is fail-fast once disconnect
+ * processing starts
+ */
+ if (udev->state == USB_STATE_NOTATTACHED)
+ break;
+
+ /* when everyone grabs locks top->bottom,
+ * non-overlapping work may be concurrent
+ */
+ down(&udev->serialize);
+ up(&hdev->serialize);
+ return t + 1;
+ }
+ }
+ usb_unlock_device(hdev);
+ return -ENODEV;
+}
+
+static void recursively_mark_NOTATTACHED(struct usb_device *udev)
+{
+ int i;
+
+ for (i = 0; i < udev->maxchild; ++i) {
+ if (udev->children[i])
+ recursively_mark_NOTATTACHED(udev->children[i]);
+ }
+ udev->state = USB_STATE_NOTATTACHED;
+}
+
+/**
+ * usb_set_device_state - change a device's current state (usbcore, hcds)
+ * @udev: pointer to device whose state should be changed
+ * @new_state: new state value to be stored
+ *
+ * udev->state is _not_ fully protected by the device lock. Although
+ * most transitions are made only while holding the lock, the state can
+ * can change to USB_STATE_NOTATTACHED at almost any time. This
+ * is so that devices can be marked as disconnected as soon as possible,
+ * without having to wait for any semaphores to be released. As a result,
+ * all changes to any device's state must be protected by the
+ * device_state_lock spinlock.
+ *
+ * Once a device has been added to the device tree, all changes to its state
+ * should be made using this routine. The state should _not_ be set directly.
+ *
+ * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
+ * Otherwise udev->state is set to new_state, and if new_state is
+ * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
+ * to USB_STATE_NOTATTACHED.
+ */
+void usb_set_device_state(struct usb_device *udev,
+ enum usb_device_state new_state)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&device_state_lock, flags);
+ if (udev->state == USB_STATE_NOTATTACHED)
+ ; /* do nothing */
+ else if (new_state != USB_STATE_NOTATTACHED)
+ udev->state = new_state;
+ else
+ recursively_mark_NOTATTACHED(udev);
+ spin_unlock_irqrestore(&device_state_lock, flags);
+}
+EXPORT_SYMBOL(usb_set_device_state);
+
+
+static void choose_address(struct usb_device *udev)
+{
+ int devnum;
+ struct usb_bus *bus = udev->bus;
+
+ /* If khubd ever becomes multithreaded, this will need a lock */
+
+ /* Try to allocate the next devnum beginning at bus->devnum_next. */
+ devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
+ bus->devnum_next);
+ if (devnum >= 128)
+ devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
+
+ bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
+
+ if (devnum < 128) {
+ set_bit(devnum, bus->devmap.devicemap);
+ udev->devnum = devnum;
+ }
+}
+
+static void release_address(struct usb_device *udev)
+{
+ if (udev->devnum > 0) {
+ clear_bit(udev->devnum, udev->bus->devmap.devicemap);
+ udev->devnum = -1;
+ }
+}
+
+/**
+ * usb_disconnect - disconnect a device (usbcore-internal)
+ * @pdev: pointer to device being disconnected
+ * Context: !in_interrupt ()
+ *
+ * Something got disconnected. Get rid of it and all of its children.
+ *
+ * If *pdev is a normal device then the parent hub must already be locked.
+ * If *pdev is a root hub then this routine will acquire the
+ * usb_bus_list_lock on behalf of the caller.
+ *
+ * Only hub drivers (including virtual root hub drivers for host
+ * controllers) should ever call this.
+ *
+ * This call is synchronous, and may not be used in an interrupt context.
+ */
+void usb_disconnect(struct usb_device **pdev)
+{
+ struct usb_device *udev = *pdev;
+ int i;
+
+ if (!udev) {
+ pr_debug ("%s nodev\n", __FUNCTION__);
+ return;
+ }
+
+ /* mark the device as inactive, so any further urb submissions for
+ * this device (and any of its children) will fail immediately.
+ * this quiesces everyting except pending urbs.
+ */
+ usb_set_device_state(udev, USB_STATE_NOTATTACHED);
+
+ /* lock the bus list on behalf of HCDs unregistering their root hubs */
+ if (!udev->parent) {
+ down(&usb_bus_list_lock);
+ usb_lock_device(udev);
+ } else
+ down(&udev->serialize);
+
+ dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
+
+ /* Free up all the children before we remove this device */
+ for (i = 0; i < USB_MAXCHILDREN; i++) {
+ if (udev->children[i])
+ usb_disconnect(&udev->children[i]);
+ }
+
+ /* deallocate hcd/hardware state ... nuking all pending urbs and
+ * cleaning up all state associated with the current configuration
+ * so that the hardware is now fully quiesced.
+ */
+ usb_disable_device(udev, 0);
+
+ /* Free the device number, remove the /proc/bus/usb entry and
+ * the sysfs attributes, and delete the parent's children[]
+ * (or root_hub) pointer.
+ */
+ dev_dbg (&udev->dev, "unregistering device\n");
+ release_address(udev);
+ usbfs_remove_device(udev);
+ usb_remove_sysfs_dev_files(udev);
+
+ /* Avoid races with recursively_mark_NOTATTACHED() */
+ spin_lock_irq(&device_state_lock);
+ *pdev = NULL;
+ spin_unlock_irq(&device_state_lock);
+
+ if (!udev->parent) {
+ usb_unlock_device(udev);
+ up(&usb_bus_list_lock);
+ } else
+ up(&udev->serialize);
+
+ device_unregister(&udev->dev);
+}
+
+static int choose_configuration(struct usb_device *udev)
+{
+ int c, i;
+
+ /* NOTE: this should interact with hub power budgeting */
+
+ c = udev->config[0].desc.bConfigurationValue;
+ if (udev->descriptor.bNumConfigurations != 1) {
+ for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
+ struct usb_interface_descriptor *desc;
+
+ /* heuristic: Linux is more likely to have class
+ * drivers, so avoid vendor-specific interfaces.
+ */
+ desc = &udev->config[i].intf_cache[0]
+ ->altsetting->desc;
+ if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
+ continue;
+ /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
+ * MSFT needs this to be the first config; never use
+ * it as the default unless Linux has host-side RNDIS.
+ * A second config would ideally be CDC-Ethernet, but
+ * may instead be the "vendor specific" CDC subset
+ * long used by ARM Linux for sa1100 or pxa255.
+ */
+ if (desc->bInterfaceClass == USB_CLASS_COMM
+ && desc->bInterfaceSubClass == 2
+ && desc->bInterfaceProtocol == 0xff) {
+ c = udev->config[1].desc.bConfigurationValue;
+ continue;
+ }
+ c = udev->config[i].desc.bConfigurationValue;
+ break;
+ }
+ dev_info(&udev->dev,
+ "configuration #%d chosen from %d choices\n",
+ c, udev->descriptor.bNumConfigurations);
+ }
+ return c;
+}
+
+#ifdef DEBUG
+static void show_string(struct usb_device *udev, char *id, char *string)
+{
+ if (!string)
+ return;
+ dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
+}
+
+#else
+static inline void show_string(struct usb_device *udev, char *id, char *string)
+{}
+#endif
+
+static void get_string(struct usb_device *udev, char **string, int index)
+{
+ char *buf;
+
+ if (!index)
+ return;
+ buf = kmalloc(256, GFP_KERNEL);
+ if (!buf)
+ return;
+ if (usb_string(udev, index, buf, 256) > 0)
+ *string = buf;
+ else
+ kfree(buf);
+}
+
+
+#ifdef CONFIG_USB_OTG
+#include "otg_whitelist.h"
+#endif
+
+/**
+ * usb_new_device - perform initial device setup (usbcore-internal)
+ * @udev: newly addressed device (in ADDRESS state)
+ *
+ * This is called with devices which have been enumerated, but not yet
+ * configured. The device descriptor is available, but not descriptors
+ * for any device configuration. The caller must have locked udev and
+ * either the parent hub (if udev is a normal device) or else the
+ * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
+ * udev has already been installed, but udev is not yet visible through
+ * sysfs or other filesystem code.
+ *
+ * Returns 0 for success (device is configured and listed, with its
+ * interfaces, in sysfs); else a negative errno value.
+ *
+ * This call is synchronous, and may not be used in an interrupt context.
+ *
+ * Only the hub driver should ever call this; root hub registration
+ * uses it indirectly.
+ */
+int usb_new_device(struct usb_device *udev)
+{
+ int err;
+ int c;
+
+ err = usb_get_configuration(udev);
+ if (err < 0) {
+ dev_err(&udev->dev, "can't read configurations, error %d\n",
+ err);
+ goto fail;
+ }
+
+ /* read the standard strings and cache them if present */
+ get_string(udev, &udev->product, udev->descriptor.iProduct);
+ get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
+ get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
+
+ /* Tell the world! */
+ dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
+ "SerialNumber=%d\n",
+ udev->descriptor.iManufacturer,
+ udev->descriptor.iProduct,
+ udev->descriptor.iSerialNumber);
+ show_string(udev, "Product", udev->product);
+ show_string(udev, "Manufacturer", udev->manufacturer);
+ show_string(udev, "SerialNumber", udev->serial);
+
+#ifdef CONFIG_USB_OTG
+ /*
+ * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
+ * to wake us after we've powered off VBUS; and HNP, switching roles
+ * "host" to "peripheral". The OTG descriptor helps figure this out.
+ */
+ if (!udev->bus->is_b_host
+ && udev->config
+ && udev->parent == udev->bus->root_hub) {
+ struct usb_otg_descriptor *desc = 0;
+ struct usb_bus *bus = udev->bus;
+
+ /* descriptor may appear anywhere in config */
+ if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
+ le16_to_cpu(udev->config[0].desc.wTotalLength),
+ USB_DT_OTG, (void **) &desc) == 0) {
+ if (desc->bmAttributes & USB_OTG_HNP) {
+ unsigned port1;
+ struct usb_device *root = udev->parent;
+
+ for (port1 = 1; port1 <= root->maxchild;
+ port1++) {
+ if (root->children[port1-1] == udev)
+ break;
+ }
+
+ dev_info(&udev->dev,
+ "Dual-Role OTG device on %sHNP port\n",
+ (port1 == bus->otg_port)
+ ? "" : "non-");
+
+ /* enable HNP before suspend, it's simpler */
+ if (port1 == bus->otg_port)
+ bus->b_hnp_enable = 1;
+ err = usb_control_msg(udev,
+ usb_sndctrlpipe(udev, 0),
+ USB_REQ_SET_FEATURE, 0,
+ bus->b_hnp_enable
+ ? USB_DEVICE_B_HNP_ENABLE
+ : USB_DEVICE_A_ALT_HNP_SUPPORT,
+ 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
+ if (err < 0) {
+ /* OTG MESSAGE: report errors here,
+ * customize to match your product.
+ */
+ dev_info(&udev->dev,
+ "can't set HNP mode; %d\n",
+ err);
+ bus->b_hnp_enable = 0;
+ }
+ }
+ }
+ }
+
+ if (!is_targeted(udev)) {
+
+ /* Maybe it can talk to us, though we can't talk to it.
+ * (Includes HNP test device.)
+ */
+ if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
+ static int __usb_suspend_device (struct usb_device *,
+ int port1, pm_message_t state);
+ err = __usb_suspend_device(udev,
+ udev->bus->otg_port,
+ PMSG_SUSPEND);
+ if (err < 0)
+ dev_dbg(&udev->dev, "HNP fail, %d\n", err);
+ }
+ err = -ENODEV;
+ goto fail;
+ }
+#endif
+
+ /* put device-specific files into sysfs */
+ err = device_add (&udev->dev);
+ if (err) {
+ dev_err(&udev->dev, "can't device_add, error %d\n", err);
+ goto fail;
+ }
+ usb_create_sysfs_dev_files (udev);
+
+ /* choose and set the configuration. that registers the interfaces
+ * with the driver core, and lets usb device drivers bind to them.
+ */
+ c = choose_configuration(udev);
+ if (c < 0)
+ dev_warn(&udev->dev,
+ "can't choose an initial configuration\n");
+ else {
+ err = usb_set_configuration(udev, c);
+ if (err) {
+ dev_err(&udev->dev, "can't set config #%d, error %d\n",
+ c, err);
+ usb_remove_sysfs_dev_files(udev);
+ device_del(&udev->dev);
+ goto fail;
+ }
+ }
+
+ /* USB device state == configured ... usable */
+
+ /* add a /proc/bus/usb entry */
+ usbfs_add_device(udev);
+ return 0;
+
+fail:
+ usb_set_device_state(udev, USB_STATE_NOTATTACHED);
+ return err;
+}
+
+
+static int hub_port_status(struct usb_hub *hub, int port1,
+ u16 *status, u16 *change)
+{
+ int ret;
+
+ ret = get_port_status(hub->hdev, port1, &hub->status->port);
+ if (ret < 0)
+ dev_err (hub->intfdev,
+ "%s failed (err = %d)\n", __FUNCTION__, ret);
+ else {
+ *status = le16_to_cpu(hub->status->port.wPortStatus);
+ *change = le16_to_cpu(hub->status->port.wPortChange);
+ ret = 0;
+ }
+ return ret;
+}
+
+#define PORT_RESET_TRIES 5
+#define SET_ADDRESS_TRIES 2
+#define GET_DESCRIPTOR_TRIES 2
+#define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
+#define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
+
+#define HUB_ROOT_RESET_TIME 50 /* times are in msec */
+#define HUB_SHORT_RESET_TIME 10
+#define HUB_LONG_RESET_TIME 200
+#define HUB_RESET_TIMEOUT 500
+
+static int hub_port_wait_reset(struct usb_hub *hub, int port1,
+ struct usb_device *udev, unsigned int delay)
+{
+ int delay_time, ret;
+ u16 portstatus;
+ u16 portchange;
+
+ for (delay_time = 0;
+ delay_time < HUB_RESET_TIMEOUT;
+ delay_time += delay) {
+ /* wait to give the device a chance to reset */
+ msleep(delay);
+
+ /* read and decode port status */
+ ret = hub_port_status(hub, port1, &portstatus, &portchange);
+ if (ret < 0)
+ return ret;
+
+ /* Device went away? */
+ if (!(portstatus & USB_PORT_STAT_CONNECTION))
+ return -ENOTCONN;
+
+ /* bomb out completely if something weird happened */
+ if ((portchange & USB_PORT_STAT_C_CONNECTION))
+ return -EINVAL;
+
+ /* if we`ve finished resetting, then break out of the loop */
+ if (!(portstatus & USB_PORT_STAT_RESET) &&
+ (portstatus & USB_PORT_STAT_ENABLE)) {
+ if (portstatus & USB_PORT_STAT_HIGH_SPEED)
+ udev->speed = USB_SPEED_HIGH;
+ else if (portstatus & USB_PORT_STAT_LOW_SPEED)
+ udev->speed = USB_SPEED_LOW;
+ else
+ udev->speed = USB_SPEED_FULL;
+ return 0;
+ }
+
+ /* switch to the long delay after two short delay failures */
+ if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
+ delay = HUB_LONG_RESET_TIME;
+
+ dev_dbg (hub->intfdev,
+ "port %d not reset yet, waiting %dms\n",
+ port1, delay);
+ }
+
+ return -EBUSY;
+}
+
+static int hub_port_reset(struct usb_hub *hub, int port1,
+ struct usb_device *udev, unsigned int delay)
+{
+ int i, status;
+
+ /* Reset the port */
+ for (i = 0; i < PORT_RESET_TRIES; i++) {
+ status = set_port_feature(hub->hdev,
+ port1, USB_PORT_FEAT_RESET);
+ if (status)
+ dev_err(hub->intfdev,
+ "cannot reset port %d (err = %d)\n",
+ port1, status);
+ else {
+ status = hub_port_wait_reset(hub, port1, udev, delay);
+ if (status)
+ dev_dbg(hub->intfdev,
+ "port_wait_reset: err = %d\n",
+ status);
+ }
+
+ /* return on disconnect or reset */
+ switch (status) {
+ case 0:
+ /* TRSTRCY = 10 ms */
+ msleep(10);
+ /* FALL THROUGH */
+ case -ENOTCONN:
+ case -ENODEV:
+ clear_port_feature(hub->hdev,
+ port1, USB_PORT_FEAT_C_RESET);
+ /* FIXME need disconnect() for NOTATTACHED device */
+ usb_set_device_state(udev, status
+ ? USB_STATE_NOTATTACHED
+ : USB_STATE_DEFAULT);
+ return status;
+ }
+
+ dev_dbg (hub->intfdev,
+ "port %d not enabled, trying reset again...\n",
+ port1);
+ delay = HUB_LONG_RESET_TIME;
+ }
+
+ dev_err (hub->intfdev,
+ "Cannot enable port %i. Maybe the USB cable is bad?\n",
+ 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
+ * and will re-enumerate if there actually is a device attached.
+ */
+static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
+{
+ dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
+ hub_port_disable(hub, port1, 1);
+
+ /* FIXME let caller ask to power down the port:
+ * - some devices won't enumerate without a VBUS power cycle
+ * - SRP saves power that way
+ * - usb_suspend_device(dev,PM_SUSPEND_DISK)
+ * That's easy if this hub can switch power per-port, and
+ * khubd reactivates the port later (timer, SRP, etc).
+ * Powerdown must be optional, because of reset/DFU.
+ */
+
+ set_bit(port1, hub->change_bits);
+ kick_khubd(hub);
+}
+
+
+#ifdef CONFIG_USB_SUSPEND
+
+/*
+ * Selective port suspend reduces power; most suspended devices draw
+ * less than 500 uA. It's also used in OTG, along with remote wakeup.
+ * All devices below the suspended port are also suspended.
+ *
+ * Devices leave suspend state when the host wakes them up. Some devices
+ * also support "remote wakeup", where the device can activate the USB
+ * tree above them to deliver data, such as a keypress or packet. In
+ * some cases, this wakes the USB host.
+ */
+static int hub_port_suspend(struct usb_hub *hub, int port1,
+ struct usb_device *udev)
+{
+ int status;
+
+ // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
+
+ /* enable remote wakeup when appropriate; this lets the device
+ * wake up the upstream hub (including maybe the root hub).
+ *
+ * NOTE: OTG devices may issue remote wakeup (or SRP) even when
+ * we don't explicitly enable it here.
+ */
+ if (udev->actconfig
+ // && FIXME (remote wakeup enabled on this bus)
+ // ... currently assuming it's always appropriate
+ && (udev->actconfig->desc.bmAttributes
+ & USB_CONFIG_ATT_WAKEUP) != 0) {
+ status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
+ USB_DEVICE_REMOTE_WAKEUP, 0,
+ NULL, 0,
+ USB_CTRL_SET_TIMEOUT);
+ if (status)
+ dev_dbg(&udev->dev,
+ "won't remote wakeup, status %d\n",
+ status);
+ }
+
+ /* see 7.1.7.6 */
+ status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
+ if (status) {
+ dev_dbg(hub->intfdev,
+ "can't suspend port %d, status %d\n",
+ port1, status);
+ /* paranoia: "should not happen" */
+ (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
+ USB_DEVICE_REMOTE_WAKEUP, 0,
+ NULL, 0,
+ USB_CTRL_SET_TIMEOUT);
+ } else {
+ /* device has up to 10 msec to fully suspend */
+ dev_dbg(&udev->dev, "usb suspend\n");
+ usb_set_device_state(udev, USB_STATE_SUSPENDED);
+ msleep(10);
+ }
+ return status;
+}
+
+/*
+ * Devices on USB hub ports have only one "suspend" state, corresponding
+ * to ACPI D2 (PM_SUSPEND_MEM), "may cause the device to lose some context".
+ * State transitions include:
+ *
+ * - suspend, resume ... when the VBUS power link stays live
+ * - suspend, disconnect ... VBUS lost
+ *
+ * Once VBUS drop breaks the circuit, the port it's using has to go through
+ * normal re-enumeration procedures, starting with enabling VBUS power.
+ * Other than re-initializing the hub (plug/unplug, except for root hubs),
+ * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
+ * timer, no SRP, no requests through sysfs.
+ */
+static int __usb_suspend_device (struct usb_device *udev, int port1,
+ pm_message_t state)
+{
+ int status;
+
+ /* caller owns the udev device lock */
+ if (port1 < 0)
+ return port1;
+
+ if (udev->state == USB_STATE_SUSPENDED
+ || udev->state == USB_STATE_NOTATTACHED) {
+ return 0;
+ }
+
+ /* suspend interface drivers; if this is a hub, it
+ * suspends the child devices
+ */
+ if (udev->actconfig) {
+ int i;
+
+ for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+ struct usb_interface *intf;
+ struct usb_driver *driver;
+
+ intf = udev->actconfig->interface[i];
+ if (state <= intf->dev.power.power_state)
+ continue;
+ if (!intf->dev.driver)
+ continue;
+ driver = to_usb_driver(intf->dev.driver);
+
+ if (driver->suspend) {
+ status = driver->suspend(intf, state);
+ if (intf->dev.power.power_state != state
+ || status)
+ dev_err(&intf->dev,
+ "suspend %d fail, code %d\n",
+ state, status);
+ }
+
+ /* only drivers with suspend() can ever resume();
+ * and after power loss, even they won't.
+ * bus_rescan_devices() can rebind drivers later.
+ *
+ * FIXME the PM core self-deadlocks when unbinding
+ * drivers during suspend/resume ... everything grabs
+ * dpm_sem (not a spinlock, ugh). we want to unbind,
+ * since we know every driver's probe/disconnect works
+ * even for drivers that can't suspend.
+ */
+ if (!driver->suspend || state > PM_SUSPEND_MEM) {
+#if 1
+ dev_warn(&intf->dev, "resume is unsafe!\n");
+#else
+ down_write(&usb_bus_type.rwsem);
+ device_release_driver(&intf->dev);
+ up_write(&usb_bus_type.rwsem);
+#endif
+ }
+ }
+ }
+
+ /*
+ * FIXME this needs port power off call paths too, to help force
+ * USB into the "generic" PM model. At least for devices on
+ * ports that aren't using ganged switching (usually root hubs).
+ *
+ * NOTE: SRP-capable links should adopt more aggressive poweroff
+ * policies (when HNP doesn't apply) once we have mechanisms to
+ * turn power back on! (Likely not before 2.7...)
+ */
+ if (state > PM_SUSPEND_MEM) {
+ dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
+ }
+
+ /* "global suspend" of the HC-to-USB interface (root hub), or
+ * "selective suspend" of just one hub-device link.
+ */
+ if (!udev->parent) {
+ struct usb_bus *bus = udev->bus;
+ if (bus && bus->op->hub_suspend) {
+ status = bus->op->hub_suspend (bus);
+ if (status == 0) {
+ dev_dbg(&udev->dev, "usb suspend\n");
+ usb_set_device_state(udev,
+ USB_STATE_SUSPENDED);
+ }
+ } else
+ status = -EOPNOTSUPP;
+ } else
+ status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
+ udev);
+
+ if (status == 0)
+ udev->dev.power.power_state = state;
+ return status;
+}
+
+/**
+ * usb_suspend_device - suspend a usb device
+ * @udev: device that's no longer in active use
+ * @state: PMSG_SUSPEND to suspend
+ * Context: must be able to sleep; device not locked
+ *
+ * Suspends a USB device that isn't in active use, conserving power.
+ * Devices may wake out of a suspend, if anything important happens,
+ * using the remote wakeup mechanism. They may also be taken out of
+ * suspend by the host, using usb_resume_device(). It's also routine
+ * to disconnect devices while they are suspended.
+ *
+ * Suspending OTG devices may trigger HNP, if that's been enabled
+ * between a pair of dual-role devices. That will change roles, such
+ * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
+ *
+ * Returns 0 on success, else negative errno.
+ */
+int usb_suspend_device(struct usb_device *udev, pm_message_t state)
+{
+ int port1, status;
+
+ port1 = locktree(udev);
+ if (port1 < 0)
+ return port1;
+
+ status = __usb_suspend_device(udev, port1, state);
+ usb_unlock_device(udev);
+ return status;
+}
+
+/*
+ * hardware resume signaling is finished, either because of selective
+ * resume (by host) or remote wakeup (by device) ... now see what changed
+ * in the tree that's rooted at this device.
+ */
+static int finish_port_resume(struct usb_device *udev)
+{
+ int status;
+ u16 devstatus;
+
+ /* caller owns the udev device lock */
+ dev_dbg(&udev->dev, "usb resume\n");
+
+ /* usb ch9 identifies four variants of SUSPENDED, based on what
+ * state the device resumes to. Linux currently won't see the
+ * first two on the host side; they'd be inside hub_port_init()
+ * during many timeouts, but khubd can't suspend until later.
+ */
+ usb_set_device_state(udev, udev->actconfig
+ ? USB_STATE_CONFIGURED
+ : USB_STATE_ADDRESS);
+ udev->dev.power.power_state = PMSG_ON;
+
+ /* 10.5.4.5 says be sure devices in the tree are still there.
+ * For now let's assume the device didn't go crazy on resume,
+ * and device drivers will know about any resume quirks.
+ */
+ status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
+ if (status < 0)
+ dev_dbg(&udev->dev,
+ "gone after usb resume? status %d\n",
+ status);
+ else if (udev->actconfig) {
+ unsigned i;
+
+ le16_to_cpus(&devstatus);
+ if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
+ status = usb_control_msg(udev,
+ usb_sndctrlpipe(udev, 0),
+ USB_REQ_CLEAR_FEATURE,
+ USB_RECIP_DEVICE,
+ USB_DEVICE_REMOTE_WAKEUP, 0,
+ NULL, 0,
+ USB_CTRL_SET_TIMEOUT);
+ if (status) {
+ dev_dbg(&udev->dev, "disable remote "
+ "wakeup, status %d\n", status);
+ status = 0;
+ }
+ }
+
+ /* resume interface drivers; if this is a hub, it
+ * resumes the child devices
+ */
+ for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+ struct usb_interface *intf;
+ struct usb_driver *driver;
+
+ intf = udev->actconfig->interface[i];
+ if (intf->dev.power.power_state == PM_SUSPEND_ON)
+ continue;
+ if (!intf->dev.driver) {
+ /* FIXME maybe force to alt 0 */
+ continue;
+ }
+ driver = to_usb_driver(intf->dev.driver);
+
+ /* bus_rescan_devices() may rebind drivers */
+ if (!driver->resume)
+ continue;
+
+ /* can we do better than just logging errors? */
+ status = driver->resume(intf);
+ if (intf->dev.power.power_state != PM_SUSPEND_ON
+ || status)
+ dev_dbg(&intf->dev,
+ "resume fail, state %d code %d\n",
+ intf->dev.power.power_state, status);
+ }
+ status = 0;
+
+ } else if (udev->devnum <= 0) {
+ dev_dbg(&udev->dev, "bogus resume!\n");
+ status = -EINVAL;
+ }
+ return status;
+}
+
+static int
+hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
+{
+ int status;
+
+ // dev_dbg(hub->intfdev, "resume port %d\n", port1);
+
+ /* see 7.1.7.7; affects power usage, but not budgeting */
+ status = clear_port_feature(hub->hdev,
+ port1, USB_PORT_FEAT_SUSPEND);
+ if (status) {
+ dev_dbg(hub->intfdev,
+ "can't resume port %d, status %d\n",
+ port1, status);
+ } else {
+ u16 devstatus;
+ u16 portchange;
+
+ /* drive resume for at least 20 msec */
+ if (udev)
+ dev_dbg(&udev->dev, "RESUME\n");
+ msleep(25);
+
+#define LIVE_FLAGS ( USB_PORT_STAT_POWER \
+ | USB_PORT_STAT_ENABLE \
+ | USB_PORT_STAT_CONNECTION)
+
+ /* Virtual root hubs can trigger on GET_PORT_STATUS to
+ * stop resume signaling. Then finish the resume
+ * sequence.
+ */
+ devstatus = portchange = 0;
+ status = hub_port_status(hub, port1,
+ &devstatus, &portchange);
+ if (status < 0
+ || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
+ || (devstatus & USB_PORT_STAT_SUSPEND) != 0
+ ) {
+ dev_dbg(hub->intfdev,
+ "port %d status %04x.%04x after resume, %d\n",
+ port1, portchange, devstatus, status);
+ } else {
+ /* TRSMRCY = 10 msec */
+ msleep(10);
+ if (udev)
+ status = finish_port_resume(udev);
+ }
+ }
+ if (status < 0)
+ hub_port_logical_disconnect(hub, port1);
+
+ return status;
+}
+
+static int hub_resume (struct usb_interface *intf);
+
+/**
+ * usb_resume_device - re-activate a suspended usb device
+ * @udev: device to re-activate
+ * Context: must be able to sleep; device not locked
+ *
+ * This will re-activate the suspended device, increasing power usage
+ * while letting drivers communicate again with its endpoints.
+ * USB resume explicitly guarantees that the power session between
+ * the host and the device is the same as it was when the device
+ * suspended.
+ *
+ * Returns 0 on success, else negative errno.
+ */
+int usb_resume_device(struct usb_device *udev)
+{
+ int port1, status;
+
+ port1 = locktree(udev);
+ if (port1 < 0)
+ return port1;
+
+ /* "global resume" of the HC-to-USB interface (root hub), or
+ * selective resume of one hub-to-device port
+ */
+ if (!udev->parent) {
+ struct usb_bus *bus = udev->bus;
+ if (bus && bus->op->hub_resume) {
+ status = bus->op->hub_resume (bus);
+ } else
+ status = -EOPNOTSUPP;
+ if (status == 0) {
+ dev_dbg(&udev->dev, "usb resume\n");
+ /* TRSMRCY = 10 msec */
+ msleep(10);
+ usb_set_device_state (udev, USB_STATE_CONFIGURED);
+ udev->dev.power.power_state = PMSG_ON;
+ status = hub_resume (udev
+ ->actconfig->interface[0]);
+ }
+ } else if (udev->state == USB_STATE_SUSPENDED) {
+ // NOTE this fails if parent is also suspended...
+ status = hub_port_resume(hdev_to_hub(udev->parent),
+ port1, udev);
+ } else {
+ status = 0;
+ }
+ if (status < 0) {
+ dev_dbg(&udev->dev, "can't resume, status %d\n",
+ status);
+ }
+
+ usb_unlock_device(udev);
+
+ /* rebind drivers that had no suspend() */
+ if (status == 0) {
+ usb_lock_all_devices();
+ bus_rescan_devices(&usb_bus_type);
+ usb_unlock_all_devices();
+ }
+ return status;
+}
+
+static int remote_wakeup(struct usb_device *udev)
+{
+ int status = 0;
+
+ /* don't repeat RESUME sequence if this device
+ * was already woken up by some other task
+ */
+ down(&udev->serialize);
+ if (udev->state == USB_STATE_SUSPENDED) {
+ dev_dbg(&udev->dev, "RESUME (wakeup)\n");
+ /* TRSMRCY = 10 msec */
+ msleep(10);
+ status = finish_port_resume(udev);
+ }
+ up(&udev->serialize);
+ return status;
+}
+
+static int hub_suspend(struct usb_interface *intf, pm_message_t state)
+{
+ struct usb_hub *hub = usb_get_intfdata (intf);
+ struct usb_device *hdev = hub->hdev;
+ unsigned port1;
+ int status;
+
+ /* stop khubd and related activity */
+ hub_quiesce(hub);
+
+ /* then suspend every port */
+ for (port1 = 1; port1 <= hdev->maxchild; port1++) {
+ struct usb_device *udev;
+
+ udev = hdev->children [port1-1];
+ if (!udev)
+ continue;
+ down(&udev->serialize);
+ status = __usb_suspend_device(udev, port1, state);
+ up(&udev->serialize);
+ if (status < 0)
+ dev_dbg(&intf->dev, "suspend port %d --> %d\n",
+ port1, status);
+ }
+
+ intf->dev.power.power_state = state;
+ return 0;
+}
+
+static int hub_resume(struct usb_interface *intf)
+{
+ struct usb_device *hdev = interface_to_usbdev(intf);
+ struct usb_hub *hub = usb_get_intfdata (intf);
+ unsigned port1;
+ int status;
+
+ if (intf->dev.power.power_state == PM_SUSPEND_ON)
+ return 0;
+
+ for (port1 = 1; port1 <= hdev->maxchild; port1++) {
+ struct usb_device *udev;
+ u16 portstat, portchange;
+
+ udev = hdev->children [port1-1];
+ status = hub_port_status(hub, port1, &portstat, &portchange);
+ if (status == 0) {
+ if (portchange & USB_PORT_STAT_C_SUSPEND) {
+ clear_port_feature(hdev, port1,
+ USB_PORT_FEAT_C_SUSPEND);
+ portchange &= ~USB_PORT_STAT_C_SUSPEND;
+ }
+
+ /* let khubd handle disconnects etc */
+ if (portchange)
+ continue;
+ }
+
+ if (!udev || status < 0)
+ continue;
+ down (&udev->serialize);
+ if (portstat & USB_PORT_STAT_SUSPEND)
+ status = hub_port_resume(hub, port1, udev);
+ else {
+ status = finish_port_resume(udev);
+ if (status < 0) {
+ dev_dbg(&intf->dev, "resume port %d --> %d\n",
+ port1, status);
+ hub_port_logical_disconnect(hub, port1);
+ }
+ }
+ up(&udev->serialize);
+ }
+ intf->dev.power.power_state = PMSG_ON;
+
+ hub->resume_root_hub = 0;
+ hub_activate(hub);
+ return 0;
+}
+
+void usb_resume_root_hub(struct usb_device *hdev)
+{
+ struct usb_hub *hub = hdev_to_hub(hdev);
+
+ hub->resume_root_hub = 1;
+ kick_khubd(hub);
+}
+
+#else /* !CONFIG_USB_SUSPEND */
+
+int usb_suspend_device(struct usb_device *udev, pm_message_t state)
+{
+ return 0;
+}
+
+int usb_resume_device(struct usb_device *udev)
+{
+ return 0;
+}
+
+#define hub_suspend NULL
+#define hub_resume NULL
+#define remote_wakeup(x) 0
+
+#endif /* CONFIG_USB_SUSPEND */
+
+EXPORT_SYMBOL(usb_suspend_device);
+EXPORT_SYMBOL(usb_resume_device);
+
+
+
+/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
+ *
+ * Between connect detection and reset signaling there must be a delay
+ * of 100ms at least for debounce and power-settling. The corresponding
+ * timer shall restart whenever the downstream port detects a disconnect.
+ *
+ * Apparently there are some bluetooth and irda-dongles and a number of
+ * low-speed devices for which this debounce period may last over a second.
+ * Not covered by the spec - but easy to deal with.
+ *
+ * This implementation uses a 1500ms total debounce timeout; if the
+ * connection isn't stable by then it returns -ETIMEDOUT. It checks
+ * every 25ms for transient disconnects. When the port status has been
+ * unchanged for 100ms it returns the port status.
+ */
+
+#define HUB_DEBOUNCE_TIMEOUT 1500
+#define HUB_DEBOUNCE_STEP 25
+#define HUB_DEBOUNCE_STABLE 100
+
+static int hub_port_debounce(struct usb_hub *hub, int port1)
+{
+ int ret;
+ int total_time, stable_time = 0;
+ u16 portchange, portstatus;
+ unsigned connection = 0xffff;
+
+ for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
+ ret = hub_port_status(hub, port1, &portstatus, &portchange);
+ if (ret < 0)
+ return ret;
+
+ if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
+ (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
+ stable_time += HUB_DEBOUNCE_STEP;
+ if (stable_time >= HUB_DEBOUNCE_STABLE)
+ break;
+ } else {
+ stable_time = 0;
+ connection = portstatus & USB_PORT_STAT_CONNECTION;
+ }
+
+ if (portchange & USB_PORT_STAT_C_CONNECTION) {
+ clear_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_C_CONNECTION);
+ }
+
+ if (total_time >= HUB_DEBOUNCE_TIMEOUT)
+ break;
+ msleep(HUB_DEBOUNCE_STEP);
+ }
+
+ dev_dbg (hub->intfdev,
+ "debounce: port %d: total %dms stable %dms status 0x%x\n",
+ port1, total_time, stable_time, portstatus);
+
+ if (stable_time < HUB_DEBOUNCE_STABLE)
+ return -ETIMEDOUT;
+ return portstatus;
+}
+
+static void ep0_reinit(struct usb_device *udev)
+{
+ usb_disable_endpoint(udev, 0 + USB_DIR_IN);
+ usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
+ udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
+}
+
+#define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
+#define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
+
+static int hub_set_address(struct usb_device *udev)
+{
+ int retval;
+
+ if (udev->devnum == 0)
+ return -EINVAL;
+ if (udev->state == USB_STATE_ADDRESS)
+ return 0;
+ if (udev->state != USB_STATE_DEFAULT)
+ return -EINVAL;
+ retval = usb_control_msg(udev, usb_sndaddr0pipe(),
+ USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
+ NULL, 0, USB_CTRL_SET_TIMEOUT);
+ if (retval == 0) {
+ usb_set_device_state(udev, USB_STATE_ADDRESS);
+ ep0_reinit(udev);
+ }
+ return retval;
+}
+
+/* Reset device, (re)assign address, get device descriptor.
+ * Device connection must be stable, no more debouncing needed.
+ * Returns device in USB_STATE_ADDRESS, except on error.
+ *
+ * If this is called for an already-existing device (as part of
+ * usb_reset_device), the caller must own the device lock. For a
+ * newly detected device that is not accessible through any global
+ * pointers, it's not necessary to lock the device.
+ */
+static int
+hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
+ int retry_counter)
+{
+ static DECLARE_MUTEX(usb_address0_sem);
+
+ struct usb_device *hdev = hub->hdev;
+ int i, j, retval;
+ unsigned delay = HUB_SHORT_RESET_TIME;
+ enum usb_device_speed oldspeed = udev->speed;
+
+ /* root hub ports have a slightly longer reset period
+ * (from USB 2.0 spec, section 7.1.7.5)
+ */
+ if (!hdev->parent) {
+ delay = HUB_ROOT_RESET_TIME;
+ if (port1 == hdev->bus->otg_port)
+ hdev->bus->b_hnp_enable = 0;
+ }
+
+ /* Some low speed devices have problems with the quick delay, so */
+ /* be a bit pessimistic with those devices. RHbug #23670 */
+ if (oldspeed == USB_SPEED_LOW)
+ delay = HUB_LONG_RESET_TIME;
+
+ down(&usb_address0_sem);
+
+ /* Reset the device; full speed may morph to high speed */
+ retval = hub_port_reset(hub, port1, udev, delay);
+ if (retval < 0) /* error or disconnect */
+ goto fail;
+ /* success, speed is known */
+ retval = -ENODEV;
+
+ if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
+ dev_dbg(&udev->dev, "device reset changed speed!\n");
+ goto fail;
+ }
+ oldspeed = udev->speed;
+
+ /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
+ * it's fixed size except for full speed devices.
+ */
+ switch (udev->speed) {
+ case USB_SPEED_HIGH: /* fixed at 64 */
+ udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
+ break;
+ case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
+ /* to determine the ep0 maxpacket size, try to read
+ * the device descriptor to get bMaxPacketSize0 and
+ * then correct our initial guess.
+ */
+ udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
+ break;
+ case USB_SPEED_LOW: /* fixed at 8 */
+ udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
+ break;
+ default:
+ goto fail;
+ }
+
+ dev_info (&udev->dev,
+ "%s %s speed USB device using %s and address %d\n",
+ (udev->config) ? "reset" : "new",
+ ({ char *speed; switch (udev->speed) {
+ case USB_SPEED_LOW: speed = "low"; break;
+ case USB_SPEED_FULL: speed = "full"; break;
+ case USB_SPEED_HIGH: speed = "high"; break;
+ default: speed = "?"; break;
+ }; speed;}),
+ udev->bus->controller->driver->name,
+ udev->devnum);
+
+ /* Set up TT records, if needed */
+ if (hdev->tt) {
+ udev->tt = hdev->tt;
+ udev->ttport = hdev->ttport;
+ } else if (udev->speed != USB_SPEED_HIGH
+ && hdev->speed == USB_SPEED_HIGH) {
+ udev->tt = &hub->tt;
+ udev->ttport = port1;
+ }
+
+ /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
+ * Because device hardware and firmware is sometimes buggy in
+ * this area, and this is how Linux has done it for ages.
+ * Change it cautiously.
+ *
+ * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
+ * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
+ * so it may help with some non-standards-compliant devices.
+ * Otherwise we start with SET_ADDRESS and then try to read the
+ * first 8 bytes of the device descriptor to get the ep0 maxpacket
+ * value.
+ */
+ for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
+ if (USE_NEW_SCHEME(retry_counter)) {
+ struct usb_device_descriptor *buf;
+ int r = 0;
+
+#define GET_DESCRIPTOR_BUFSIZE 64
+ buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
+ if (!buf) {
+ retval = -ENOMEM;
+ continue;
+ }
+
+ /* Use a short timeout the first time through,
+ * so that recalcitrant full-speed devices with
+ * 8- or 16-byte ep0-maxpackets won't slow things
+ * down tremendously by NAKing the unexpectedly
+ * early status stage. Also, retry on all errors;
+ * some devices are flakey.
+ */
+ for (j = 0; j < 3; ++j) {
+ buf->bMaxPacketSize0 = 0;
+ r = usb_control_msg(udev, usb_rcvaddr0pipe(),
+ USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
+ USB_DT_DEVICE << 8, 0,
+ buf, GET_DESCRIPTOR_BUFSIZE,
+ (i ? USB_CTRL_GET_TIMEOUT : 1000));
+ switch (buf->bMaxPacketSize0) {
+ case 8: case 16: case 32: case 64:
+ if (buf->bDescriptorType ==
+ USB_DT_DEVICE) {
+ r = 0;
+ break;
+ }
+ /* FALL THROUGH */
+ default:
+ if (r == 0)
+ r = -EPROTO;
+ break;
+ }
+ if (r == 0)
+ break;
+ }
+ udev->descriptor.bMaxPacketSize0 =
+ buf->bMaxPacketSize0;
+ kfree(buf);
+
+ retval = hub_port_reset(hub, port1, udev, delay);
+ if (retval < 0) /* error or disconnect */
+ goto fail;
+ if (oldspeed != udev->speed) {
+ dev_dbg(&udev->dev,
+ "device reset changed speed!\n");
+ retval = -ENODEV;
+ goto fail;
+ }
+ if (r) {
+ dev_err(&udev->dev, "device descriptor "
+ "read/%s, error %d\n",
+ "64", r);
+ retval = -EMSGSIZE;
+ continue;
+ }
+#undef GET_DESCRIPTOR_BUFSIZE
+ }
+
+ for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
+ retval = hub_set_address(udev);
+ if (retval >= 0)
+ break;
+ msleep(200);
+ }
+ if (retval < 0) {
+ dev_err(&udev->dev,
+ "device not accepting address %d, error %d\n",
+ udev->devnum, retval);
+ goto fail;
+ }
+
+ /* cope with hardware quirkiness:
+ * - let SET_ADDRESS settle, some device hardware wants it
+ * - read ep0 maxpacket even for high and low speed,
+ */
+ msleep(10);
+ if (USE_NEW_SCHEME(retry_counter))
+ break;
+
+ retval = usb_get_device_descriptor(udev, 8);
+ if (retval < 8) {
+ dev_err(&udev->dev, "device descriptor "
+ "read/%s, error %d\n",
+ "8", retval);
+ if (retval >= 0)
+ retval = -EMSGSIZE;
+ } else {
+ retval = 0;
+ break;
+ }
+ }
+ if (retval)
+ goto fail;
+
+ i = udev->descriptor.bMaxPacketSize0;
+ if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
+ if (udev->speed != USB_SPEED_FULL ||
+ !(i == 8 || i == 16 || i == 32 || i == 64)) {
+ dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
+ retval = -EMSGSIZE;
+ goto fail;
+ }
+ dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
+ udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
+ ep0_reinit(udev);
+ }
+
+ retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
+ if (retval < (signed)sizeof(udev->descriptor)) {
+ dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
+ "all", retval);
+ if (retval >= 0)
+ retval = -ENOMSG;
+ goto fail;
+ }
+
+ retval = 0;
+
+fail:
+ if (retval)
+ hub_port_disable(hub, port1, 0);
+ up(&usb_address0_sem);
+ return retval;
+}
+
+static void
+check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
+{
+ struct usb_qualifier_descriptor *qual;
+ int status;
+
+ qual = kmalloc (sizeof *qual, SLAB_KERNEL);
+ if (qual == NULL)
+ return;
+
+ status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
+ qual, sizeof *qual);
+ if (status == sizeof *qual) {
+ dev_info(&udev->dev, "not running at top speed; "
+ "connect to a high speed hub\n");
+ /* hub LEDs are probably harder to miss than syslog */
+ if (hub->has_indicators) {
+ hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
+ schedule_work (&hub->leds);
+ }
+ }
+ kfree (qual);
+}
+
+static unsigned
+hub_power_remaining (struct usb_hub *hub)
+{
+ struct usb_device *hdev = hub->hdev;
+ int remaining;
+ unsigned i;
+
+ remaining = hub->power_budget;
+ if (!remaining) /* self-powered */
+ return 0;
+
+ for (i = 0; i < hdev->maxchild; i++) {
+ struct usb_device *udev = hdev->children[i];
+ int delta, ceiling;
+
+ if (!udev)
+ continue;
+
+ /* 100mA per-port ceiling, or 8mA for OTG ports */
+ if (i != (udev->bus->otg_port - 1) || hdev->parent)
+ ceiling = 50;
+ else
+ ceiling = 4;
+
+ if (udev->actconfig)
+ delta = udev->actconfig->desc.bMaxPower;
+ else
+ delta = ceiling;
+ // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
+ if (delta > ceiling)
+ dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
+ 2 * (delta - ceiling), 2 * ceiling);
+ remaining -= delta;
+ }
+ if (remaining < 0) {
+ dev_warn(hub->intfdev,
+ "%dmA over power budget!\n",
+ -2 * remaining);
+ remaining = 0;
+ }
+ return remaining;
+}
+
+/* Handle physical or logical connection change events.
+ * This routine is called when:
+ * a port connection-change occurs;
+ * a port enable-change occurs (often caused by EMI);
+ * usb_reset_device() encounters changed descriptors (as from
+ * a firmware download)
+ * caller already locked the hub
+ */
+static void hub_port_connect_change(struct usb_hub *hub, int port1,
+ u16 portstatus, u16 portchange)
+{
+ struct usb_device *hdev = hub->hdev;
+ struct device *hub_dev = hub->intfdev;
+ int status, i;
+
+ dev_dbg (hub_dev,
+ "port %d, status %04x, change %04x, %s\n",
+ port1, portstatus, portchange, portspeed (portstatus));
+
+ if (hub->has_indicators) {
+ set_port_led(hub, port1, HUB_LED_AUTO);
+ hub->indicator[port1-1] = INDICATOR_AUTO;
+ }
+
+ /* Disconnect any existing devices under this port */
+ if (hdev->children[port1-1])
+ usb_disconnect(&hdev->children[port1-1]);
+ clear_bit(port1, hub->change_bits);
+
+#ifdef CONFIG_USB_OTG
+ /* during HNP, don't repeat the debounce */
+ if (hdev->bus->is_b_host)
+ portchange &= ~USB_PORT_STAT_C_CONNECTION;
+#endif
+
+ if (portchange & USB_PORT_STAT_C_CONNECTION) {
+ status = hub_port_debounce(hub, port1);
+ if (status < 0) {
+ dev_err (hub_dev,
+ "connect-debounce failed, port %d disabled\n",
+ port1);
+ goto done;
+ }
+ portstatus = status;
+ }
+
+ /* Return now if nothing is connected */
+ if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
+
+ /* maybe switch power back on (e.g. root hub was reset) */
+ if ((hub->descriptor->wHubCharacteristics
+ & HUB_CHAR_LPSM) < 2
+ && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
+ set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
+
+ if (portstatus & USB_PORT_STAT_ENABLE)
+ goto done;
+ return;
+ }
+
+#ifdef CONFIG_USB_SUSPEND
+ /* If something is connected, but the port is suspended, wake it up. */
+ if (portstatus & USB_PORT_STAT_SUSPEND) {
+ status = hub_port_resume(hub, port1, NULL);
+ if (status < 0) {
+ dev_dbg(hub_dev,
+ "can't clear suspend on port %d; %d\n",
+ port1, status);
+ goto done;
+ }
+ }
+#endif
+
+ for (i = 0; i < SET_CONFIG_TRIES; i++) {
+ struct usb_device *udev;
+
+ /* reallocate for each attempt, since references
+ * to the previous one can escape in various ways
+ */
+ udev = usb_alloc_dev(hdev, hdev->bus, port1);
+ if (!udev) {
+ dev_err (hub_dev,
+ "couldn't allocate port %d usb_device\n",
+ port1);
+ goto done;
+ }
+
+ usb_set_device_state(udev, USB_STATE_POWERED);
+ udev->speed = USB_SPEED_UNKNOWN;
+
+ /* set the address */
+ choose_address(udev);
+ if (udev->devnum <= 0) {
+ status = -ENOTCONN; /* Don't retry */
+ goto loop;
+ }
+
+ /* reset and get descriptor */
+ status = hub_port_init(hub, udev, port1, i);
+ if (status < 0)
+ goto loop;
+
+ /* consecutive bus-powered hubs aren't reliable; they can
+ * violate the voltage drop budget. if the new child has
+ * a "powered" LED, users should notice we didn't enable it
+ * (without reading syslog), even without per-port LEDs
+ * on the parent.
+ */
+ if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
+ && hub->power_budget) {
+ u16 devstat;
+
+ status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
+ &devstat);
+ if (status < 0) {
+ dev_dbg(&udev->dev, "get status %d ?\n", status);
+ goto loop_disable;
+ }
+ cpu_to_le16s(&devstat);
+ if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
+ dev_err(&udev->dev,
+ "can't connect bus-powered hub "
+ "to this port\n");
+ if (hub->has_indicators) {
+ hub->indicator[port1-1] =
+ INDICATOR_AMBER_BLINK;
+ schedule_work (&hub->leds);
+ }
+ status = -ENOTCONN; /* Don't retry */
+ goto loop_disable;
+ }
+ }
+
+ /* check for devices running slower than they could */
+ if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
+ && udev->speed == USB_SPEED_FULL
+ && highspeed_hubs != 0)
+ check_highspeed (hub, udev, port1);
+
+ /* Store the parent's children[] pointer. At this point
+ * udev becomes globally accessible, although presumably
+ * no one will look at it until hdev is unlocked.
+ */
+ down (&udev->serialize);
+ status = 0;
+
+ /* We mustn't add new devices if the parent hub has
+ * been disconnected; we would race with the
+ * recursively_mark_NOTATTACHED() routine.
+ */
+ spin_lock_irq(&device_state_lock);
+ if (hdev->state == USB_STATE_NOTATTACHED)
+ status = -ENOTCONN;
+ else
+ hdev->children[port1-1] = udev;
+ spin_unlock_irq(&device_state_lock);
+
+ /* Run it through the hoops (find a driver, etc) */
+ if (!status) {
+ status = usb_new_device(udev);
+ if (status) {
+ spin_lock_irq(&device_state_lock);
+ hdev->children[port1-1] = NULL;
+ spin_unlock_irq(&device_state_lock);
+ }
+ }
+
+ up (&udev->serialize);
+ if (status)
+ goto loop_disable;
+
+ status = hub_power_remaining(hub);
+ if (status)
+ dev_dbg(hub_dev,
+ "%dmA power budget left\n",
+ 2 * status);
+
+ return;
+
+loop_disable:
+ hub_port_disable(hub, port1, 1);
+loop:
+ ep0_reinit(udev);
+ release_address(udev);
+ usb_put_dev(udev);
+ if (status == -ENOTCONN)
+ break;
+ }
+
+done:
+ hub_port_disable(hub, port1, 1);
+}
+
+static void hub_events(void)
+{
+ struct list_head *tmp;
+ struct usb_device *hdev;
+ struct usb_interface *intf;
+ struct usb_hub *hub;
+ struct device *hub_dev;
+ u16 hubstatus;
+ u16 hubchange;
+ u16 portstatus;
+ u16 portchange;
+ int i, ret;
+ int connect_change;
+
+ /*
+ * We restart the list every time to avoid a deadlock with
+ * deleting hubs downstream from this one. This should be
+ * safe since we delete the hub from the event list.
+ * Not the most efficient, but avoids deadlocks.
+ */
+ while (1) {
+
+ /* Grab the first entry at the beginning of the list */
+ spin_lock_irq(&hub_event_lock);
+ if (list_empty(&hub_event_list)) {
+ spin_unlock_irq(&hub_event_lock);
+ break;
+ }
+
+ tmp = hub_event_list.next;
+ list_del_init(tmp);
+
+ hub = list_entry(tmp, struct usb_hub, event_list);
+ hdev = hub->hdev;
+ intf = to_usb_interface(hub->intfdev);
+ hub_dev = &intf->dev;
+
+ dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
+ hdev->state, hub->descriptor
+ ? hub->descriptor->bNbrPorts
+ : 0,
+ /* NOTE: expects max 15 ports... */
+ (u16) hub->change_bits[0],
+ (u16) hub->event_bits[0]);
+
+ usb_get_intf(intf);
+ i = hub->resume_root_hub;
+ spin_unlock_irq(&hub_event_lock);
+
+ /* Is this is a root hub wanting to be resumed? */
+ if (i)
+ usb_resume_device(hdev);
+
+ /* Lock the device, then check to see if we were
+ * disconnected while waiting for the lock to succeed. */
+ if (locktree(hdev) < 0) {
+ usb_put_intf(intf);
+ continue;
+ }
+ if (hub != usb_get_intfdata(intf))
+ goto loop;
+
+ /* If the hub has died, clean up after it */
+ if (hdev->state == USB_STATE_NOTATTACHED) {
+ hub_pre_reset(hub);
+ goto loop;
+ }
+
+ /* If this is an inactive or suspended hub, do nothing */
+ if (hub->quiescing)
+ goto loop;
+
+ if (hub->error) {
+ dev_dbg (hub_dev, "resetting for error %d\n",
+ hub->error);
+
+ ret = usb_reset_device(hdev);
+ if (ret) {
+ dev_dbg (hub_dev,
+ "error resetting hub: %d\n", ret);
+ goto loop;
+ }
+
+ hub->nerrors = 0;
+ hub->error = 0;
+ }
+
+ /* deal with port status changes */
+ for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
+ if (test_bit(i, hub->busy_bits))
+ continue;
+ connect_change = test_bit(i, hub->change_bits);
+ if (!test_and_clear_bit(i, hub->event_bits) &&
+ !connect_change && !hub->activating)
+ continue;
+
+ ret = hub_port_status(hub, i,
+ &portstatus, &portchange);
+ if (ret < 0)
+ continue;
+
+ if (hub->activating && !hdev->children[i-1] &&
+ (portstatus &
+ USB_PORT_STAT_CONNECTION))
+ connect_change = 1;
+
+ if (portchange & USB_PORT_STAT_C_CONNECTION) {
+ clear_port_feature(hdev, i,
+ USB_PORT_FEAT_C_CONNECTION);
+ connect_change = 1;
+ }
+
+ if (portchange & USB_PORT_STAT_C_ENABLE) {
+ if (!connect_change)
+ dev_dbg (hub_dev,
+ "port %d enable change, "
+ "status %08x\n",
+ i, portstatus);
+ clear_port_feature(hdev, i,
+ USB_PORT_FEAT_C_ENABLE);
+
+ /*
+ * EM interference sometimes causes badly
+ * shielded USB devices to be shutdown by
+ * the hub, this hack enables them again.
+ * Works at least with mouse driver.
+ */
+ if (!(portstatus & USB_PORT_STAT_ENABLE)
+ && !connect_change
+ && hdev->children[i-1]) {
+ dev_err (hub_dev,
+ "port %i "
+ "disabled by hub (EMI?), "
+ "re-enabling...\n",
+ i);
+ connect_change = 1;
+ }
+ }
+
+ if (portchange & USB_PORT_STAT_C_SUSPEND) {
+ clear_port_feature(hdev, i,
+ USB_PORT_FEAT_C_SUSPEND);
+ if (hdev->children[i-1]) {
+ ret = remote_wakeup(hdev->
+ children[i-1]);
+ if (ret < 0)
+ connect_change = 1;
+ } else {
+ ret = -ENODEV;
+ hub_port_disable(hub, i, 1);
+ }
+ dev_dbg (hub_dev,
+ "resume on port %d, status %d\n",
+ i, ret);
+ }
+
+ if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
+ dev_err (hub_dev,
+ "over-current change on port %d\n",
+ i);
+ clear_port_feature(hdev, i,
+ USB_PORT_FEAT_C_OVER_CURRENT);
+ hub_power_on(hub);
+ }
+
+ if (portchange & USB_PORT_STAT_C_RESET) {
+ dev_dbg (hub_dev,
+ "reset change on port %d\n",
+ i);
+ clear_port_feature(hdev, i,
+ USB_PORT_FEAT_C_RESET);
+ }
+
+ if (connect_change)
+ hub_port_connect_change(hub, i,
+ portstatus, portchange);
+ } /* end for i */
+
+ /* deal with hub status changes */
+ if (test_and_clear_bit(0, hub->event_bits) == 0)
+ ; /* do nothing */
+ else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
+ dev_err (hub_dev, "get_hub_status failed\n");
+ else {
+ if (hubchange & HUB_CHANGE_LOCAL_POWER) {
+ dev_dbg (hub_dev, "power change\n");
+ clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
+ }
+ if (hubchange & HUB_CHANGE_OVERCURRENT) {
+ dev_dbg (hub_dev, "overcurrent change\n");
+ msleep(500); /* Cool down */
+ clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
+ hub_power_on(hub);
+ }
+ }
+
+ hub->activating = 0;
+
+loop:
+ usb_unlock_device(hdev);
+ usb_put_intf(intf);
+
+ } /* end while (1) */
+}
+
+static int hub_thread(void *__unused)
+{
+ /*
+ * This thread doesn't need any user-level access,
+ * so get rid of all our resources
+ */
+
+ daemonize("khubd");
+ allow_signal(SIGKILL);
+
+ /* Send me a signal to get me die (for debugging) */
+ do {
+ hub_events();
+ wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list));
+ try_to_freeze(PF_FREEZE);
+ } while (!signal_pending(current));
+
+ pr_debug ("%s: khubd exiting\n", usbcore_name);
+ complete_and_exit(&khubd_exited, 0);
+}
+
+static struct usb_device_id hub_id_table [] = {
+ { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
+ .bDeviceClass = USB_CLASS_HUB},
+ { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
+ .bInterfaceClass = USB_CLASS_HUB},
+ { } /* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE (usb, hub_id_table);
+
+static struct usb_driver hub_driver = {
+ .owner = THIS_MODULE,
+ .name = "hub",
+ .probe = hub_probe,
+ .disconnect = hub_disconnect,
+ .suspend = hub_suspend,
+ .resume = hub_resume,
+ .ioctl = hub_ioctl,
+ .id_table = hub_id_table,
+};
+
+int usb_hub_init(void)
+{
+ pid_t pid;
+
+ if (usb_register(&hub_driver) < 0) {
+ printk(KERN_ERR "%s: can't register hub driver\n",
+ usbcore_name);
+ return -1;
+ }
+
+ pid = kernel_thread(hub_thread, NULL, CLONE_KERNEL);
+ if (pid >= 0) {
+ khubd_pid = pid;
+
+ return 0;
+ }
+
+ /* Fall through if kernel_thread failed */
+ usb_deregister(&hub_driver);
+ printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
+
+ return -1;
+}
+
+void usb_hub_cleanup(void)
+{
+ int ret;
+
+ /* Kill the thread */
+ ret = kill_proc(khubd_pid, SIGKILL, 1);
+
+ wait_for_completion(&khubd_exited);
+
+ /*
+ * Hub resources are freed for us by usb_deregister. It calls
+ * usb_driver_purge on every device which in turn calls that
+ * devices disconnect function if it is using this driver.
+ * The hub_disconnect function takes care of releasing the
+ * individual hub resources. -greg
+ */
+ usb_deregister(&hub_driver);
+} /* usb_hub_cleanup() */
+
+
+static int config_descriptors_changed(struct usb_device *udev)
+{
+ unsigned index;
+ unsigned len = 0;
+ struct usb_config_descriptor *buf;
+
+ for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
+ if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
+ len = le16_to_cpu(udev->config[index].desc.wTotalLength);
+ }
+ buf = kmalloc (len, SLAB_KERNEL);
+ if (buf == NULL) {
+ dev_err(&udev->dev, "no mem to re-read configs after reset\n");
+ /* assume the worst */
+ return 1;
+ }
+ for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
+ int length;
+ int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
+
+ length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
+ old_length);
+ if (length < old_length) {
+ dev_dbg(&udev->dev, "config index %d, error %d\n",
+ index, length);
+ break;
+ }
+ if (memcmp (buf, udev->rawdescriptors[index], old_length)
+ != 0) {
+ dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
+ index, buf->bConfigurationValue);
+ break;
+ }
+ }
+ kfree(buf);
+ return index != udev->descriptor.bNumConfigurations;
+}
+
+/**
+ * usb_reset_device - perform a USB port reset to reinitialize a device
+ * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
+ *
+ * WARNING - don't reset any device unless drivers for all of its
+ * interfaces are expecting that reset! Maybe some driver->reset()
+ * method should eventually help ensure sufficient cooperation.
+ *
+ * Do a port reset, reassign the device's address, and establish its
+ * former operating configuration. If the reset fails, or the device's
+ * descriptors change from their values before the reset, or the original
+ * configuration and altsettings cannot be restored, a flag will be set
+ * telling khubd to pretend the device has been disconnected and then
+ * re-connected. All drivers will be unbound, and the device will be
+ * re-enumerated and probed all over again.
+ *
+ * Returns 0 if the reset succeeded, -ENODEV if the device has been
+ * flagged for logical disconnection, or some other negative error code
+ * if the reset wasn't even attempted.
+ *
+ * The caller must own the device lock. For example, it's safe to use
+ * this from a driver probe() routine after downloading new firmware.
+ * For calls that might not occur during probe(), drivers should lock
+ * the device using usb_lock_device_for_reset().
+ */
+int usb_reset_device(struct usb_device *udev)
+{
+ struct usb_device *parent_hdev = udev->parent;
+ struct usb_hub *parent_hub;
+ struct usb_device_descriptor descriptor = udev->descriptor;
+ struct usb_hub *hub = NULL;
+ int i, ret = 0, port1 = -1;
+
+ if (udev->state == USB_STATE_NOTATTACHED ||
+ udev->state == USB_STATE_SUSPENDED) {
+ dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
+ udev->state);
+ return -EINVAL;
+ }
+
+ if (!parent_hdev) {
+ /* this requires hcd-specific logic; see OHCI hc_restart() */
+ dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
+ return -EISDIR;
+ }
+
+ for (i = 0; i < parent_hdev->maxchild; i++)
+ if (parent_hdev->children[i] == udev) {
+ port1 = i + 1;
+ break;
+ }
+
+ if (port1 < 0) {
+ /* If this ever happens, it's very bad */
+ dev_err(&udev->dev, "Can't locate device's port!\n");
+ return -ENOENT;
+ }
+ parent_hub = hdev_to_hub(parent_hdev);
+
+ /* If we're resetting an active hub, take some special actions */
+ if (udev->actconfig &&
+ udev->actconfig->interface[0]->dev.driver ==
+ &hub_driver.driver &&
+ (hub = hdev_to_hub(udev)) != NULL) {
+ hub_pre_reset(hub);
+ }
+
+ set_bit(port1, parent_hub->busy_bits);
+ for (i = 0; i < SET_CONFIG_TRIES; ++i) {
+
+ /* ep0 maxpacket size may change; let the HCD know about it.
+ * Other endpoints will be handled by re-enumeration. */
+ ep0_reinit(udev);
+ ret = hub_port_init(parent_hub, udev, port1, i);
+ if (ret >= 0)
+ break;
+ }
+ clear_bit(port1, parent_hub->busy_bits);
+ if (ret < 0)
+ goto re_enumerate;
+
+ /* Device might have changed firmware (DFU or similar) */
+ if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
+ || config_descriptors_changed (udev)) {
+ dev_info(&udev->dev, "device firmware changed\n");
+ udev->descriptor = descriptor; /* for disconnect() calls */
+ goto re_enumerate;
+ }
+
+ if (!udev->actconfig)
+ goto done;
+
+ ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ USB_REQ_SET_CONFIGURATION, 0,
+ udev->actconfig->desc.bConfigurationValue, 0,
+ NULL, 0, USB_CTRL_SET_TIMEOUT);
+ if (ret < 0) {
+ dev_err(&udev->dev,
+ "can't restore configuration #%d (error=%d)\n",
+ udev->actconfig->desc.bConfigurationValue, ret);
+ goto re_enumerate;
+ }
+ usb_set_device_state(udev, USB_STATE_CONFIGURED);
+
+ for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+ struct usb_interface *intf = udev->actconfig->interface[i];
+ struct usb_interface_descriptor *desc;
+
+ /* set_interface resets host side toggle even
+ * for altsetting zero. the interface may have no driver.
+ */
+ desc = &intf->cur_altsetting->desc;
+ ret = usb_set_interface(udev, desc->bInterfaceNumber,
+ desc->bAlternateSetting);
+ if (ret < 0) {
+ dev_err(&udev->dev, "failed to restore interface %d "
+ "altsetting %d (error=%d)\n",
+ desc->bInterfaceNumber,
+ desc->bAlternateSetting,
+ ret);
+ goto re_enumerate;
+ }
+ }
+
+done:
+ if (hub)
+ hub_post_reset(hub);
+ return 0;
+
+re_enumerate:
+ hub_port_logical_disconnect(parent_hub, port1);
+ return -ENODEV;
+}