* message.c - synchronous message handling
*/
-#include <linux/config.h>
-
-#ifdef CONFIG_USB_DEBUG
- #define DEBUG
-#else
- #undef DEBUG
-#endif
-
#include <linux/pci.h> /* for scatterlist macros */
#include <linux/usb.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/timer.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
#include <asm/byteorder.h>
+#include <asm/scatterlist.h>
#include "hcd.h" /* for usbcore internals */
#include "usb.h"
-static void usb_api_blocking_completion(struct urb *urb, struct pt_regs *regs)
+static void usb_api_blocking_completion(struct urb *urb)
{
complete((struct completion *)urb->context);
}
-static void timeout_kill(unsigned long data)
-{
- struct urb *urb = (struct urb *) data;
-
- dev_warn(&urb->dev->dev, "%s timeout on ep%d%s\n",
- usb_pipecontrol(urb->pipe) ? "control" : "bulk",
- usb_pipeendpoint(urb->pipe),
- usb_pipein(urb->pipe) ? "in" : "out");
- usb_unlink_urb(urb);
-}
-
-// Starts urb and waits for completion or timeout
-// note that this call is NOT interruptible, while
-// many device driver i/o requests should be interruptible
-static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length)
+/*
+ * Starts urb and waits for completion or timeout. Note that this call
+ * is NOT interruptible. Many device driver i/o requests should be
+ * interruptible and therefore these drivers should implement their
+ * own interruptible routines.
+ */
+static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length)
{
- struct completion done;
- struct timer_list timer;
- int status;
+ struct completion done;
+ unsigned long expire;
+ int status;
init_completion(&done);
urb->context = &done;
- urb->transfer_flags |= URB_ASYNC_UNLINK;
urb->actual_length = 0;
status = usb_submit_urb(urb, GFP_NOIO);
-
- if (status == 0) {
- if (timeout > 0) {
- init_timer(&timer);
- timer.expires = jiffies + timeout;
- timer.data = (unsigned long)urb;
- timer.function = timeout_kill;
- /* grr. timeout _should_ include submit delays. */
- add_timer(&timer);
- }
- wait_for_completion(&done);
+ if (unlikely(status))
+ goto out;
+
+ expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT;
+ if (!wait_for_completion_timeout(&done, expire)) {
+
+ dev_dbg(&urb->dev->dev,
+ "%s timed out on ep%d%s len=%d/%d\n",
+ current->comm,
+ usb_pipeendpoint(urb->pipe),
+ usb_pipein(urb->pipe) ? "in" : "out",
+ urb->actual_length,
+ urb->transfer_buffer_length);
+
+ usb_kill_urb(urb);
+ status = urb->status == -ENOENT ? -ETIMEDOUT : urb->status;
+ } else
status = urb->status;
- /* note: HCDs return ETIMEDOUT for other reasons too */
- if (status == -ECONNRESET)
- status = -ETIMEDOUT;
- if (timeout > 0)
- del_timer_sync(&timer);
- }
-
+out:
if (actual_length)
*actual_length = urb->actual_length;
+
usb_free_urb(urb);
return status;
}
/*-------------------------------------------------------------------*/
// returns status (negative) or length (positive)
-int usb_internal_control_msg(struct usb_device *usb_dev, unsigned int pipe,
- struct usb_ctrlrequest *cmd, void *data, int len, int timeout)
+static int usb_internal_control_msg(struct usb_device *usb_dev,
+ unsigned int pipe,
+ struct usb_ctrlrequest *cmd,
+ void *data, int len, int timeout)
{
struct urb *urb;
int retv;
* @index: USB message index value
* @data: pointer to the data to send
* @size: length in bytes of the data to send
- * @timeout: time in jiffies to wait for the message to complete before
+ * @timeout: time in msecs to wait for the message to complete before
* timing out (if 0 the wait is forever)
* Context: !in_interrupt ()
*
}
+/**
+ * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion
+ * @usb_dev: pointer to the usb device to send the message to
+ * @pipe: endpoint "pipe" to send the message to
+ * @data: pointer to the data to send
+ * @len: length in bytes of the data to send
+ * @actual_length: pointer to a location to put the actual length transferred in bytes
+ * @timeout: time in msecs to wait for the message to complete before
+ * timing out (if 0 the wait is forever)
+ * Context: !in_interrupt ()
+ *
+ * This function sends a simple interrupt message to a specified endpoint and
+ * waits for the message to complete, or timeout.
+ *
+ * If successful, it returns 0, otherwise a negative error number. The number
+ * of actual bytes transferred will be stored in the actual_length paramater.
+ *
+ * Don't use this function from within an interrupt context, like a bottom half
+ * handler. If you need an asynchronous message, or need to send a message
+ * from within interrupt context, use usb_submit_urb() If a thread in your
+ * driver uses this call, make sure your disconnect() method can wait for it to
+ * complete. Since you don't have a handle on the URB used, you can't cancel
+ * the request.
+ */
+int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
+ void *data, int len, int *actual_length, int timeout)
+{
+ return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout);
+}
+EXPORT_SYMBOL_GPL(usb_interrupt_msg);
+
/**
* usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion
* @usb_dev: pointer to the usb device to send the message to
* @data: pointer to the data to send
* @len: length in bytes of the data to send
* @actual_length: pointer to a location to put the actual length transferred in bytes
- * @timeout: time in jiffies to wait for the message to complete before
+ * @timeout: time in msecs to wait for the message to complete before
* timing out (if 0 the wait is forever)
* Context: !in_interrupt ()
*
* If a thread in your driver uses this call, make sure your disconnect()
* method can wait for it to complete. Since you don't have a handle on
* the URB used, you can't cancel the request.
+ *
+ * Because there is no usb_interrupt_msg() and no USBDEVFS_INTERRUPT
+ * ioctl, users are forced to abuse this routine by using it to submit
+ * URBs for interrupt endpoints. We will take the liberty of creating
+ * an interrupt URB (with the default interval) if the target is an
+ * interrupt endpoint.
*/
int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
void *data, int len, int *actual_length, int timeout)
{
struct urb *urb;
+ struct usb_host_endpoint *ep;
- if (len < 0)
+ ep = (usb_pipein(pipe) ? usb_dev->ep_in : usb_dev->ep_out)
+ [usb_pipeendpoint(pipe)];
+ if (!ep || len < 0)
return -EINVAL;
- urb=usb_alloc_urb(0, GFP_KERNEL);
+ urb = usb_alloc_urb(0, GFP_KERNEL);
if (!urb)
return -ENOMEM;
- usb_fill_bulk_urb(urb, usb_dev, pipe, data, len,
- usb_api_blocking_completion, NULL);
-
- return usb_start_wait_urb(urb,timeout,actual_length);
+ if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
+ USB_ENDPOINT_XFER_INT) {
+ pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30);
+ usb_fill_int_urb(urb, usb_dev, pipe, data, len,
+ usb_api_blocking_completion, NULL,
+ ep->desc.bInterval);
+ } else
+ usb_fill_bulk_urb(urb, usb_dev, pipe, data, len,
+ usb_api_blocking_completion, NULL);
+
+ return usb_start_wait_urb(urb, timeout, actual_length);
}
/*-------------------------------------------------------------------*/
kfree (io->urbs);
io->urbs = NULL;
}
- if (io->dev->dev.dma_mask != 0)
+ if (io->dev->dev.dma_mask != NULL)
usb_buffer_unmap_sg (io->dev, io->pipe, io->sg, io->nents);
io->dev = NULL;
}
-static void sg_complete (struct urb *urb, struct pt_regs *regs)
+static void sg_complete (struct urb *urb)
{
- struct usb_sg_request *io = (struct usb_sg_request *) urb->context;
+ struct usb_sg_request *io = urb->context;
spin_lock (&io->lock);
// BUG ();
}
- if (urb->status && urb->status != -ECONNRESET) {
+ if (io->status == 0 && urb->status && urb->status != -ECONNRESET) {
int i, found, status;
io->status = urb->status;
/* the previous urbs, and this one, completed already.
* unlink pending urbs so they won't rx/tx bad data.
+ * careful: unlink can sometimes be synchronous...
*/
+ spin_unlock (&io->lock);
for (i = 0, found = 0; i < io->entries; i++) {
if (!io->urbs [i] || !io->urbs [i]->dev)
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);
} else if (urb == io->urbs [i])
found = 1;
}
+ spin_lock (&io->lock);
}
urb->dev = NULL;
struct scatterlist *sg,
int nents,
size_t length,
- int mem_flags
+ gfp_t mem_flags
)
{
int i;
/* not all host controllers use DMA (like the mainstream pci ones);
* they can use PIO (sl811) or be software over another transport.
*/
- dma = (dev->dev.dma_mask != 0);
+ dma = (dev->dev.dma_mask != NULL);
if (dma)
io->entries = usb_buffer_map_sg (dev, pipe, sg, nents);
else
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;
* (2) error, where io->status is a negative errno value. The number
* of io->bytes transferred before the error is usually less
* than requested, and can be nonzero.
- * (3) cancelation, a type of error with status -ECONNRESET that
+ * (3) cancellation, a type of error with status -ECONNRESET that
* is initiated by usb_sg_cancel().
*
* When this function returns, all memory allocated through usb_sg_init() or
int retval;
io->urbs [i]->dev = io->dev;
- retval = usb_submit_urb (io->urbs [i], SLAB_ATOMIC);
+ retval = usb_submit_urb (io->urbs [i], GFP_ATOMIC);
/* after we submit, let completions or cancelations fire;
* we handshake using io->status.
int i;
io->status = -ECONNRESET;
+ spin_unlock (&io->lock);
for (i = 0; i < io->entries; i++) {
int retval;
dev_warn (&io->dev->dev, "%s, unlink --> %d\n",
__FUNCTION__, retval);
}
+ spin_lock (&io->lock);
}
spin_unlock_irqrestore (&io->lock, flags);
}
*
* Gets a USB descriptor. Convenience functions exist to simplify
* getting some types of descriptors. Use
- * usb_get_device_descriptor() for USB_DT_DEVICE (not exported),
- * and usb_get_string() or usb_string() for USB_DT_STRING.
+ * usb_get_string() or usb_string() for USB_DT_STRING.
* Device (USB_DT_DEVICE) and configuration descriptors (USB_DT_CONFIG)
* are part of the device structure.
* In addition to a number of USB-standard descriptors, some
result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
(type << 8) + index, 0, buf, size,
- HZ * USB_CTRL_GET_TIMEOUT);
+ USB_CTRL_GET_TIMEOUT);
if (result == 0 || result == -EPIPE)
continue;
if (result > 1 && ((u8 *)buf)[1] != type) {
* Returns the number of bytes received on success, or else the status code
* returned by the underlying usb_control_msg() call.
*/
-int usb_get_string(struct usb_device *dev, unsigned short langid,
- unsigned char index, void *buf, int size)
+static int usb_get_string(struct usb_device *dev, unsigned short langid,
+ unsigned char index, void *buf, int size)
{
int i;
int result;
result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
(USB_DT_STRING << 8) + index, langid, buf, size,
- HZ * USB_CTRL_GET_TIMEOUT);
+ USB_CTRL_GET_TIMEOUT);
if (!(result == 0 || result == -EPIPE))
break;
}
return result;
}
+static void usb_try_string_workarounds(unsigned char *buf, int *length)
+{
+ int newlength, oldlength = *length;
+
+ for (newlength = 2; newlength + 1 < oldlength; newlength += 2)
+ if (!isprint(buf[newlength]) || buf[newlength + 1])
+ break;
+
+ if (newlength > 2) {
+ buf[0] = newlength;
+ *length = newlength;
+ }
+}
+
static int usb_string_sub(struct usb_device *dev, unsigned int langid,
unsigned int index, unsigned char *buf)
{
/* If that failed try to read the descriptor length, then
* ask for just that many bytes */
- if (rc < 0) {
+ if (rc < 2) {
rc = usb_get_string(dev, langid, index, buf, 2);
if (rc == 2)
rc = usb_get_string(dev, langid, index, buf, buf[0]);
}
- if (rc >= 0) {
+ if (rc >= 2) {
+ if (!buf[0] && !buf[1])
+ usb_try_string_workarounds(buf, &rc);
+
/* There might be extra junk at the end of the descriptor */
if (buf[0] < rc)
rc = buf[0];
- if (rc < 2)
- rc = -EINVAL;
+
+ rc = rc - (rc & 1); /* force a multiple of two */
}
+
+ if (rc < 2)
+ rc = (rc < 0 ? rc : -EINVAL);
+
return rc;
}
int err;
unsigned int u, idx;
+ if (dev->state == USB_STATE_SUSPENDED)
+ return -EHOSTUNREACH;
if (size <= 0 || !buf || !index)
return -EINVAL;
buf[0] = 0;
err = -EINVAL;
goto errout;
} else {
- dev->have_langid = -1;
+ dev->have_langid = 1;
dev->string_langid = tbuf[2] | (tbuf[3]<< 8);
/* always use the first langid listed */
dev_dbg (&dev->dev, "default language 0x%04x\n",
buf[idx] = 0;
err = idx;
+ if (tbuf[1] != USB_DT_STRING)
+ dev_dbg(&dev->dev, "wrong descriptor type %02x for string %d (\"%s\")\n", tbuf[1], index, buf);
+
errout:
kfree(tbuf);
return err;
}
/**
- * usb_get_device_descriptor - (re)reads the device descriptor
+ * usb_cache_string - read a string descriptor and cache it for later use
+ * @udev: the device whose string descriptor is being read
+ * @index: the descriptor index
+ *
+ * Returns a pointer to a kmalloc'ed buffer containing the descriptor string,
+ * or NULL if the index is 0 or the string could not be read.
+ */
+char *usb_cache_string(struct usb_device *udev, int index)
+{
+ char *buf;
+ char *smallbuf = NULL;
+ int len;
+
+ if (index > 0 && (buf = kmalloc(256, GFP_KERNEL)) != NULL) {
+ if ((len = usb_string(udev, index, buf, 256)) > 0) {
+ if ((smallbuf = kmalloc(++len, GFP_KERNEL)) == NULL)
+ return buf;
+ memcpy(smallbuf, buf, len);
+ }
+ kfree(buf);
+ }
+ return smallbuf;
+}
+
+/*
+ * usb_get_device_descriptor - (re)reads the device descriptor (usbcore)
* @dev: the device whose device descriptor is being updated
* @size: how much of the descriptor to read
* Context: !in_interrupt ()
*
* Updates the copy of the device descriptor stored in the device structure,
- * which dedicates space for this purpose. Note that several fields are
- * converted to the host CPU's byte order: the USB version (bcdUSB), and
- * vendors product and version fields (idVendor, idProduct, and bcdDevice).
- * That lets device drivers compare against non-byteswapped constants.
+ * which dedicates space for this purpose.
*
* Not exported, only for use by the core. If drivers really want to read
* the device descriptor directly, they can call usb_get_descriptor() with
return -ENOMEM;
ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size);
- if (ret >= 0) {
- le16_to_cpus(&desc->bcdUSB);
- le16_to_cpus(&desc->idVendor);
- le16_to_cpus(&desc->idProduct);
- le16_to_cpus(&desc->bcdDevice);
+ if (ret >= 0)
memcpy(&dev->descriptor, desc, size);
- }
kfree(desc);
return ret;
}
*/
int usb_get_status(struct usb_device *dev, int type, int target, void *data)
{
- return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
- USB_REQ_GET_STATUS, USB_DIR_IN | type, 0, target, data, 2,
- HZ * USB_CTRL_GET_TIMEOUT);
+ int ret;
+ u16 *status = kmalloc(sizeof(*status), GFP_KERNEL);
+
+ if (!status)
+ return -ENOMEM;
+
+ ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
+ USB_REQ_GET_STATUS, USB_DIR_IN | type, 0, target, status,
+ sizeof(*status), USB_CTRL_GET_TIMEOUT);
+
+ *(u16 *)data = *status;
+ kfree(status);
+ return ret;
}
/**
result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
USB_ENDPOINT_HALT, endp, NULL, 0,
- HZ * USB_CTRL_SET_TIMEOUT);
+ USB_CTRL_SET_TIMEOUT);
/* don't un-halt or force to DATA0 except on success */
if (result < 0)
*/
void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr)
{
- if (dev && dev->bus && dev->bus->op && dev->bus->op->disable)
- dev->bus->op->disable(dev, epaddr);
- else {
- unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
+ unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
+ struct usb_host_endpoint *ep;
- if (usb_endpoint_out(epaddr))
- dev->epmaxpacketout[epnum] = 0;
- else
- dev->epmaxpacketin[epnum] = 0;
+ if (!dev)
+ return;
+
+ if (usb_endpoint_out(epaddr)) {
+ ep = dev->ep_out[epnum];
+ dev->ep_out[epnum] = NULL;
+ } else {
+ ep = dev->ep_in[epnum];
+ dev->ep_in[epnum] = NULL;
}
+ if (ep && dev->bus)
+ usb_hcd_endpoint_disable(dev, ep);
}
/**
for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
struct usb_interface *interface;
- /* remove this interface */
+ /* remove this interface if it has been registered */
interface = dev->actconfig->interface[i];
+ if (!device_is_registered(&interface->dev))
+ continue;
dev_dbg (&dev->dev, "unregistering interface %s\n",
interface->dev.bus_id);
usb_remove_sysfs_intf_files(interface);
/*
* usb_enable_endpoint - Enable an endpoint for USB communications
* @dev: the device whose interface is being enabled
- * @epd: pointer to the endpoint descriptor
+ * @ep: the endpoint
*
- * Resets the endpoint toggle and stores its maxpacket value.
+ * Resets the endpoint toggle, and sets dev->ep_{in,out} pointers.
* For control endpoints, both the input and output sides are handled.
*/
-void usb_enable_endpoint(struct usb_device *dev,
- struct usb_endpoint_descriptor *epd)
+static void
+usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep)
{
- int maxsize = epd->wMaxPacketSize;
- unsigned int epaddr = epd->bEndpointAddress;
+ unsigned int epaddr = ep->desc.bEndpointAddress;
unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
- int is_control = ((epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
- USB_ENDPOINT_XFER_CONTROL);
+ int is_control;
+ is_control = ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
+ == USB_ENDPOINT_XFER_CONTROL);
if (usb_endpoint_out(epaddr) || is_control) {
usb_settoggle(dev, epnum, 1, 0);
- dev->epmaxpacketout[epnum] = maxsize;
+ dev->ep_out[epnum] = ep;
}
if (!usb_endpoint_out(epaddr) || is_control) {
usb_settoggle(dev, epnum, 0, 0);
- dev->epmaxpacketin[epnum] = maxsize;
+ dev->ep_in[epnum] = ep;
}
}
*
* Enables all the endpoints for the interface's current altsetting.
*/
-void usb_enable_interface(struct usb_device *dev,
- struct usb_interface *intf)
+static void usb_enable_interface(struct usb_device *dev,
+ struct usb_interface *intf)
{
struct usb_host_interface *alt = intf->cur_altsetting;
int i;
for (i = 0; i < alt->desc.bNumEndpoints; ++i)
- usb_enable_endpoint(dev, &alt->endpoint[i].desc);
+ usb_enable_endpoint(dev, &alt->endpoint[i]);
}
/**
ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
- alternate, interface, NULL, 0, HZ * 5);
+ alternate, interface, NULL, 0, 5000);
/* 9.4.10 says devices don't need this and are free to STALL the
* request if the interface only has one alternate setting.
*/
/* prevent submissions using previous endpoint settings */
+ if (device_is_registered(&iface->dev))
+ usb_remove_sysfs_intf_files(iface);
usb_disable_interface(dev, iface);
iface->cur_altsetting = alt;
* (Likewise, EP0 never "halts" on well designed devices.)
*/
usb_enable_interface(dev, iface);
+ if (device_is_registered(&iface->dev))
+ usb_create_sysfs_intf_files(iface);
return 0;
}
*
* Because this affects multiple interfaces, avoid using this with composite
* (multi-interface) devices. Instead, the driver for each interface may
- * use usb_set_interface() on the interfaces it claims. Resetting the whole
+ * use usb_set_interface() on the interfaces it claims. Be careful though;
+ * some devices don't support the SET_INTERFACE request, and others won't
+ * reset all the interface state (notably data toggles). Resetting the whole
* configuration would affect other drivers' interfaces.
*
+ * The caller must own the device lock.
+ *
* Returns zero on success, else a negative error code.
*/
int usb_reset_configuration(struct usb_device *dev)
if (dev->state == USB_STATE_SUSPENDED)
return -EHOSTUNREACH;
- /* caller must own dev->serialize (config won't change)
- * and the usb bus readlock (so driver bindings are stable);
- * so calls during probe() are fine
+ /* caller must have locked the device and must own
+ * the usb bus readlock (so driver bindings are stable);
+ * calls during probe() are fine
*/
for (i = 1; i < 16; ++i) {
retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_SET_CONFIGURATION, 0,
config->desc.bConfigurationValue, 0,
- NULL, 0, HZ * USB_CTRL_SET_TIMEOUT);
- if (retval < 0) {
- usb_set_device_state(dev, USB_STATE_ADDRESS);
+ NULL, 0, USB_CTRL_SET_TIMEOUT);
+ if (retval < 0)
return retval;
- }
dev->toggle[0] = dev->toggle[1] = 0;
struct usb_interface *intf = config->interface[i];
struct usb_host_interface *alt;
+ if (device_is_registered(&intf->dev))
+ usb_remove_sysfs_intf_files(intf);
alt = usb_altnum_to_altsetting(intf, 0);
/* No altsetting 0? We'll assume the first altsetting.
intf->cur_altsetting = alt;
usb_enable_interface(dev, intf);
+ if (device_is_registered(&intf->dev))
+ usb_create_sysfs_intf_files(intf);
}
return 0;
}
* usb_set_configuration - Makes a particular device setting be current
* @dev: the device whose configuration is being updated
* @configuration: the configuration being chosen.
- * Context: !in_interrupt(), caller holds dev->serialize
+ * Context: !in_interrupt(), caller owns the device lock
*
* This is used to enable non-default device modes. Not all devices
* use this kind of configurability; many devices only have one
* usb_set_interface().
*
* This call is synchronous. The calling context must be able to sleep,
- * and must not hold the driver model lock for USB; usb device driver
- * probe() methods may not use this routine.
+ * must own the device lock, and must not hold the driver model's USB
+ * bus rwsem; usb device driver probe() methods cannot use this routine.
*
* Returns zero on success, or else the status code returned by the
- * underlying call that failed. On succesful completion, each interface
+ * underlying call that failed. On successful completion, each interface
* in the original device configuration has been destroyed, and each one
* in the new configuration has been probed by all relevant usb device
* drivers currently known to the kernel.
struct usb_interface **new_interfaces = NULL;
int n, nintf;
- /* dev->serialize guards all config changes */
-
for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
if (dev->config[i].desc.bConfigurationValue == configuration) {
cp = &dev->config[i];
if (cp && configuration == 0)
dev_warn(&dev->dev, "config 0 descriptor??\n");
- if (dev->state == USB_STATE_SUSPENDED)
- return -EHOSTUNREACH;
-
/* Allocate memory for new interfaces before doing anything else,
* so that if we run out then nothing will have changed. */
n = nintf = 0;
}
for (; n < nintf; ++n) {
- new_interfaces[n] = kmalloc(
+ new_interfaces[n] = kzalloc(
sizeof(struct usb_interface),
GFP_KERNEL);
if (!new_interfaces[n]) {
return ret;
}
}
+
+ i = dev->bus_mA - cp->desc.bMaxPower * 2;
+ if (i < 0)
+ dev_warn(&dev->dev, "new config #%d exceeds power "
+ "limit by %dmA\n",
+ configuration, -i);
}
+ /* Wake up the device so we can send it the Set-Config request */
+ ret = usb_autoresume_device(dev);
+ if (ret)
+ goto free_interfaces;
+
/* if it's already configured, clear out old state first.
* getting rid of old interfaces means unbinding their drivers.
*/
if ((ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_SET_CONFIGURATION, 0, configuration, 0,
- NULL, 0, HZ * USB_CTRL_SET_TIMEOUT)) < 0)
- goto free_interfaces;
+ NULL, 0, USB_CTRL_SET_TIMEOUT)) < 0) {
+
+ /* All the old state is gone, so what else can we do?
+ * The device is probably useless now anyway.
+ */
+ cp = NULL;
+ }
dev->actconfig = cp;
- if (!cp)
+ if (!cp) {
usb_set_device_state(dev, USB_STATE_ADDRESS);
- else {
- usb_set_device_state(dev, USB_STATE_CONFIGURED);
+ usb_autosuspend_device(dev);
+ goto free_interfaces;
+ }
+ usb_set_device_state(dev, USB_STATE_CONFIGURED);
- /* Initialize the new interface structures and the
- * hc/hcd/usbcore interface/endpoint state.
- */
- for (i = 0; i < nintf; ++i) {
- struct usb_interface_cache *intfc;
- struct usb_interface *intf;
- struct usb_host_interface *alt;
-
- cp->interface[i] = intf = new_interfaces[i];
- memset(intf, 0, sizeof(*intf));
- intfc = cp->intf_cache[i];
- intf->altsetting = intfc->altsetting;
- intf->num_altsetting = intfc->num_altsetting;
- kref_get(&intfc->ref);
-
- alt = usb_altnum_to_altsetting(intf, 0);
-
- /* No altsetting 0? We'll assume the first altsetting.
- * We could use a GetInterface call, but if a device is
- * so non-compliant that it doesn't have altsetting 0
- * then I wouldn't trust its reply anyway.
- */
- if (!alt)
- alt = &intf->altsetting[0];
-
- intf->cur_altsetting = alt;
- usb_enable_interface(dev, intf);
- intf->dev.parent = &dev->dev;
- intf->dev.driver = NULL;
- intf->dev.bus = &usb_bus_type;
- intf->dev.dma_mask = dev->dev.dma_mask;
- intf->dev.release = release_interface;
- device_initialize (&intf->dev);
- sprintf (&intf->dev.bus_id[0], "%d-%s:%d.%d",
- dev->bus->busnum, dev->devpath,
- configuration,
- alt->desc.bInterfaceNumber);
- }
- kfree(new_interfaces);
+ /* Initialize the new interface structures and the
+ * hc/hcd/usbcore interface/endpoint state.
+ */
+ for (i = 0; i < nintf; ++i) {
+ struct usb_interface_cache *intfc;
+ struct usb_interface *intf;
+ struct usb_host_interface *alt;
+
+ cp->interface[i] = intf = new_interfaces[i];
+ intfc = cp->intf_cache[i];
+ intf->altsetting = intfc->altsetting;
+ intf->num_altsetting = intfc->num_altsetting;
+ kref_get(&intfc->ref);
+
+ alt = usb_altnum_to_altsetting(intf, 0);
- /* Now that all the interfaces are set up, register them
- * to trigger binding of drivers to interfaces. probe()
- * routines may install different altsettings and may
- * claim() any interfaces not yet bound. Many class drivers
- * need that: CDC, audio, video, etc.
+ /* No altsetting 0? We'll assume the first altsetting.
+ * We could use a GetInterface call, but if a device is
+ * so non-compliant that it doesn't have altsetting 0
+ * then I wouldn't trust its reply anyway.
*/
- for (i = 0; i < nintf; ++i) {
- struct usb_interface *intf = cp->interface[i];
- struct usb_interface_descriptor *desc;
-
- desc = &intf->altsetting [0].desc;
- dev_dbg (&dev->dev,
- "adding %s (config #%d, interface %d)\n",
- intf->dev.bus_id, configuration,
- desc->bInterfaceNumber);
- ret = device_add (&intf->dev);
- if (ret != 0) {
- dev_err(&dev->dev,
- "device_add(%s) --> %d\n",
- intf->dev.bus_id,
- ret);
- continue;
- }
- usb_create_sysfs_intf_files (intf);
+ if (!alt)
+ alt = &intf->altsetting[0];
+
+ intf->cur_altsetting = alt;
+ usb_enable_interface(dev, intf);
+ intf->dev.parent = &dev->dev;
+ intf->dev.driver = NULL;
+ intf->dev.bus = &usb_bus_type;
+ intf->dev.dma_mask = dev->dev.dma_mask;
+ intf->dev.release = release_interface;
+ device_initialize (&intf->dev);
+ mark_quiesced(intf);
+ sprintf (&intf->dev.bus_id[0], "%d-%s:%d.%d",
+ dev->bus->busnum, dev->devpath,
+ configuration, alt->desc.bInterfaceNumber);
+ }
+ kfree(new_interfaces);
+
+ if (cp->string == NULL)
+ cp->string = usb_cache_string(dev, cp->desc.iConfiguration);
+
+ /* Now that all the interfaces are set up, register them
+ * to trigger binding of drivers to interfaces. probe()
+ * routines may install different altsettings and may
+ * claim() any interfaces not yet bound. Many class drivers
+ * need that: CDC, audio, video, etc.
+ */
+ for (i = 0; i < nintf; ++i) {
+ struct usb_interface *intf = cp->interface[i];
+
+ dev_dbg (&dev->dev,
+ "adding %s (config #%d, interface %d)\n",
+ intf->dev.bus_id, configuration,
+ intf->cur_altsetting->desc.bInterfaceNumber);
+ ret = device_add (&intf->dev);
+ if (ret != 0) {
+ dev_err(&dev->dev, "device_add(%s) --> %d\n",
+ intf->dev.bus_id, ret);
+ continue;
}
+ usb_create_sysfs_intf_files (intf);
}
- return ret;
+ usb_autosuspend_device(dev);
+ return 0;
+}
+
+struct set_config_request {
+ struct usb_device *udev;
+ int config;
+ struct work_struct work;
+};
+
+/* Worker routine for usb_driver_set_configuration() */
+static void driver_set_config_work(struct work_struct *work)
+{
+ struct set_config_request *req =
+ container_of(work, struct set_config_request, work);
+
+ usb_lock_device(req->udev);
+ usb_set_configuration(req->udev, req->config);
+ usb_unlock_device(req->udev);
+ usb_put_dev(req->udev);
+ kfree(req);
+}
+
+/**
+ * usb_driver_set_configuration - Provide a way for drivers to change device configurations
+ * @udev: the device whose configuration is being updated
+ * @config: the configuration being chosen.
+ * Context: In process context, must be able to sleep
+ *
+ * Device interface drivers are not allowed to change device configurations.
+ * This is because changing configurations will destroy the interface the
+ * driver is bound to and create new ones; it would be like a floppy-disk
+ * driver telling the computer to replace the floppy-disk drive with a
+ * tape drive!
+ *
+ * Still, in certain specialized circumstances the need may arise. This
+ * routine gets around the normal restrictions by using a work thread to
+ * submit the change-config request.
+ *
+ * Returns 0 if the request was succesfully queued, error code otherwise.
+ * The caller has no way to know whether the queued request will eventually
+ * succeed.
+ */
+int usb_driver_set_configuration(struct usb_device *udev, int config)
+{
+ struct set_config_request *req;
+
+ req = kmalloc(sizeof(*req), GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+ req->udev = udev;
+ req->config = config;
+ INIT_WORK(&req->work, driver_set_config_work);
+
+ usb_get_dev(udev);
+ if (!schedule_work(&req->work)) {
+ usb_put_dev(udev);
+ kfree(req);
+ return -EINVAL;
+ }
+ return 0;
}
+EXPORT_SYMBOL_GPL(usb_driver_set_configuration);
// synchronous request completion model
EXPORT_SYMBOL(usb_control_msg);
// synchronous control message convenience routines
EXPORT_SYMBOL(usb_get_descriptor);
EXPORT_SYMBOL(usb_get_status);
-EXPORT_SYMBOL(usb_get_string);
EXPORT_SYMBOL(usb_string);
// synchronous calls that also maintain usbcore state