![Jörn Engel](/assets/img/avatar_default.png)
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
1529 lines
47 KiB
C
1529 lines
47 KiB
C
/*
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* message.c - synchronous message handling
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*/
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#include <linux/pci.h> /* for scatterlist macros */
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#include <linux/usb.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/timer.h>
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#include <linux/ctype.h>
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#include <linux/device.h>
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#include <asm/byteorder.h>
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#include <asm/scatterlist.h>
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#include "hcd.h" /* for usbcore internals */
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#include "usb.h"
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static void usb_api_blocking_completion(struct urb *urb, struct pt_regs *regs)
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{
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complete((struct completion *)urb->context);
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}
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static void timeout_kill(unsigned long data)
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{
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struct urb *urb = (struct urb *) data;
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usb_unlink_urb(urb);
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}
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// Starts urb and waits for completion or timeout
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// note that this call is NOT interruptible, while
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// many device driver i/o requests should be interruptible
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static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length)
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{
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struct completion done;
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struct timer_list timer;
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int status;
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init_completion(&done);
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urb->context = &done;
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urb->actual_length = 0;
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status = usb_submit_urb(urb, GFP_NOIO);
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if (status == 0) {
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if (timeout > 0) {
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init_timer(&timer);
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timer.expires = jiffies + msecs_to_jiffies(timeout);
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timer.data = (unsigned long)urb;
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timer.function = timeout_kill;
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/* grr. timeout _should_ include submit delays. */
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add_timer(&timer);
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}
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wait_for_completion(&done);
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status = urb->status;
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/* note: HCDs return ETIMEDOUT for other reasons too */
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if (status == -ECONNRESET) {
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dev_dbg(&urb->dev->dev,
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"%s timed out on ep%d%s len=%d/%d\n",
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current->comm,
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usb_pipeendpoint(urb->pipe),
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usb_pipein(urb->pipe) ? "in" : "out",
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urb->actual_length,
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urb->transfer_buffer_length
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);
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if (urb->actual_length > 0)
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status = 0;
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else
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status = -ETIMEDOUT;
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}
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if (timeout > 0)
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del_timer_sync(&timer);
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}
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if (actual_length)
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*actual_length = urb->actual_length;
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usb_free_urb(urb);
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return status;
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}
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/*-------------------------------------------------------------------*/
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// returns status (negative) or length (positive)
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static int usb_internal_control_msg(struct usb_device *usb_dev,
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unsigned int pipe,
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struct usb_ctrlrequest *cmd,
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void *data, int len, int timeout)
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{
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struct urb *urb;
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int retv;
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int length;
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urb = usb_alloc_urb(0, GFP_NOIO);
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if (!urb)
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return -ENOMEM;
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usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char *)cmd, data,
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len, usb_api_blocking_completion, NULL);
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retv = usb_start_wait_urb(urb, timeout, &length);
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if (retv < 0)
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return retv;
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else
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return length;
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}
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/**
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* usb_control_msg - Builds a control urb, sends it off and waits for completion
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* @dev: pointer to the usb device to send the message to
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* @pipe: endpoint "pipe" to send the message to
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* @request: USB message request value
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* @requesttype: USB message request type value
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* @value: USB message value
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* @index: USB message index value
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* @data: pointer to the data to send
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* @size: length in bytes of the data to send
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* @timeout: time in msecs to wait for the message to complete before
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* timing out (if 0 the wait is forever)
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* Context: !in_interrupt ()
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*
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* This function sends a simple control message to a specified endpoint
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* and waits for the message to complete, or timeout.
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*
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* If successful, it returns the number of bytes transferred, otherwise a negative error number.
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*
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* Don't use this function from within an interrupt context, like a
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* bottom half handler. If you need an asynchronous message, or need to send
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* a message from within interrupt context, use usb_submit_urb()
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* If a thread in your driver uses this call, make sure your disconnect()
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* method can wait for it to complete. Since you don't have a handle on
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* the URB used, you can't cancel the request.
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*/
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int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u8 requesttype,
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__u16 value, __u16 index, void *data, __u16 size, int timeout)
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{
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struct usb_ctrlrequest *dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO);
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int ret;
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if (!dr)
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return -ENOMEM;
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dr->bRequestType= requesttype;
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dr->bRequest = request;
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dr->wValue = cpu_to_le16p(&value);
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dr->wIndex = cpu_to_le16p(&index);
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dr->wLength = cpu_to_le16p(&size);
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//dbg("usb_control_msg");
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ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout);
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kfree(dr);
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return ret;
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}
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/**
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* usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion
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* @usb_dev: pointer to the usb device to send the message to
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* @pipe: endpoint "pipe" to send the message to
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* @data: pointer to the data to send
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* @len: length in bytes of the data to send
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* @actual_length: pointer to a location to put the actual length transferred in bytes
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* @timeout: time in msecs to wait for the message to complete before
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* timing out (if 0 the wait is forever)
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* Context: !in_interrupt ()
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*
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* This function sends a simple interrupt message to a specified endpoint and
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* waits for the message to complete, or timeout.
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*
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* If successful, it returns 0, otherwise a negative error number. The number
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* of actual bytes transferred will be stored in the actual_length paramater.
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*
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* Don't use this function from within an interrupt context, like a bottom half
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* handler. If you need an asynchronous message, or need to send a message
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* from within interrupt context, use usb_submit_urb() If a thread in your
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* driver uses this call, make sure your disconnect() method can wait for it to
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* complete. Since you don't have a handle on the URB used, you can't cancel
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* the request.
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*/
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int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
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void *data, int len, int *actual_length, int timeout)
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{
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return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout);
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}
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EXPORT_SYMBOL_GPL(usb_interrupt_msg);
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/**
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* usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion
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* @usb_dev: pointer to the usb device to send the message to
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* @pipe: endpoint "pipe" to send the message to
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* @data: pointer to the data to send
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* @len: length in bytes of the data to send
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* @actual_length: pointer to a location to put the actual length transferred in bytes
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* @timeout: time in msecs to wait for the message to complete before
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* timing out (if 0 the wait is forever)
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* Context: !in_interrupt ()
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*
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* This function sends a simple bulk message to a specified endpoint
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* and waits for the message to complete, or timeout.
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*
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* If successful, it returns 0, otherwise a negative error number.
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* The number of actual bytes transferred will be stored in the
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* actual_length paramater.
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*
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* Don't use this function from within an interrupt context, like a
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* bottom half handler. If you need an asynchronous message, or need to
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* send a message from within interrupt context, use usb_submit_urb()
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* If a thread in your driver uses this call, make sure your disconnect()
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* method can wait for it to complete. Since you don't have a handle on
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* the URB used, you can't cancel the request.
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*
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* Because there is no usb_interrupt_msg() and no USBDEVFS_INTERRUPT
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* ioctl, users are forced to abuse this routine by using it to submit
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* URBs for interrupt endpoints. We will take the liberty of creating
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* an interrupt URB (with the default interval) if the target is an
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* interrupt endpoint.
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*/
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int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
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void *data, int len, int *actual_length, int timeout)
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{
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struct urb *urb;
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struct usb_host_endpoint *ep;
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ep = (usb_pipein(pipe) ? usb_dev->ep_in : usb_dev->ep_out)
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[usb_pipeendpoint(pipe)];
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if (!ep || len < 0)
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return -EINVAL;
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urb = usb_alloc_urb(0, GFP_KERNEL);
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if (!urb)
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return -ENOMEM;
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if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
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USB_ENDPOINT_XFER_INT) {
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pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30);
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usb_fill_int_urb(urb, usb_dev, pipe, data, len,
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usb_api_blocking_completion, NULL,
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ep->desc.bInterval);
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} else
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usb_fill_bulk_urb(urb, usb_dev, pipe, data, len,
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usb_api_blocking_completion, NULL);
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return usb_start_wait_urb(urb, timeout, actual_length);
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}
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/*-------------------------------------------------------------------*/
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static void sg_clean (struct usb_sg_request *io)
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{
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if (io->urbs) {
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while (io->entries--)
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usb_free_urb (io->urbs [io->entries]);
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kfree (io->urbs);
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io->urbs = NULL;
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}
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if (io->dev->dev.dma_mask != NULL)
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usb_buffer_unmap_sg (io->dev, io->pipe, io->sg, io->nents);
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io->dev = NULL;
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}
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static void sg_complete (struct urb *urb, struct pt_regs *regs)
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{
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struct usb_sg_request *io = (struct usb_sg_request *) urb->context;
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spin_lock (&io->lock);
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/* In 2.5 we require hcds' endpoint queues not to progress after fault
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* reports, until the completion callback (this!) returns. That lets
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* device driver code (like this routine) unlink queued urbs first,
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* if it needs to, since the HC won't work on them at all. So it's
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* not possible for page N+1 to overwrite page N, and so on.
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*
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* That's only for "hard" faults; "soft" faults (unlinks) sometimes
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* complete before the HCD can get requests away from hardware,
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* though never during cleanup after a hard fault.
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*/
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if (io->status
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&& (io->status != -ECONNRESET
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|| urb->status != -ECONNRESET)
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&& urb->actual_length) {
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dev_err (io->dev->bus->controller,
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"dev %s ep%d%s scatterlist error %d/%d\n",
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io->dev->devpath,
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usb_pipeendpoint (urb->pipe),
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usb_pipein (urb->pipe) ? "in" : "out",
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urb->status, io->status);
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// BUG ();
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}
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if (io->status == 0 && urb->status && urb->status != -ECONNRESET) {
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int i, found, status;
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io->status = urb->status;
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/* the previous urbs, and this one, completed already.
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* unlink pending urbs so they won't rx/tx bad data.
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* careful: unlink can sometimes be synchronous...
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*/
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spin_unlock (&io->lock);
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for (i = 0, found = 0; i < io->entries; i++) {
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if (!io->urbs [i] || !io->urbs [i]->dev)
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continue;
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if (found) {
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status = usb_unlink_urb (io->urbs [i]);
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if (status != -EINPROGRESS
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&& status != -ENODEV
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&& status != -EBUSY)
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dev_err (&io->dev->dev,
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"%s, unlink --> %d\n",
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__FUNCTION__, status);
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} else if (urb == io->urbs [i])
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found = 1;
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}
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spin_lock (&io->lock);
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}
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urb->dev = NULL;
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/* on the last completion, signal usb_sg_wait() */
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io->bytes += urb->actual_length;
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io->count--;
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if (!io->count)
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complete (&io->complete);
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spin_unlock (&io->lock);
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}
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/**
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* usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request
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* @io: request block being initialized. until usb_sg_wait() returns,
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* treat this as a pointer to an opaque block of memory,
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* @dev: the usb device that will send or receive the data
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* @pipe: endpoint "pipe" used to transfer the data
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* @period: polling rate for interrupt endpoints, in frames or
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* (for high speed endpoints) microframes; ignored for bulk
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* @sg: scatterlist entries
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* @nents: how many entries in the scatterlist
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* @length: how many bytes to send from the scatterlist, or zero to
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* send every byte identified in the list.
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* @mem_flags: SLAB_* flags affecting memory allocations in this call
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*
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* Returns zero for success, else a negative errno value. This initializes a
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* scatter/gather request, allocating resources such as I/O mappings and urb
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* memory (except maybe memory used by USB controller drivers).
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*
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* The request must be issued using usb_sg_wait(), which waits for the I/O to
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* complete (or to be canceled) and then cleans up all resources allocated by
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* usb_sg_init().
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*
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* The request may be canceled with usb_sg_cancel(), either before or after
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* usb_sg_wait() is called.
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*/
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int usb_sg_init (
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struct usb_sg_request *io,
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struct usb_device *dev,
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unsigned pipe,
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unsigned period,
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struct scatterlist *sg,
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int nents,
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size_t length,
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gfp_t mem_flags
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)
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{
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int i;
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int urb_flags;
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int dma;
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if (!io || !dev || !sg
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|| usb_pipecontrol (pipe)
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|| usb_pipeisoc (pipe)
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|| nents <= 0)
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return -EINVAL;
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spin_lock_init (&io->lock);
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io->dev = dev;
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io->pipe = pipe;
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io->sg = sg;
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io->nents = nents;
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/* not all host controllers use DMA (like the mainstream pci ones);
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* they can use PIO (sl811) or be software over another transport.
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*/
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dma = (dev->dev.dma_mask != NULL);
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if (dma)
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io->entries = usb_buffer_map_sg (dev, pipe, sg, nents);
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else
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io->entries = nents;
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/* initialize all the urbs we'll use */
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if (io->entries <= 0)
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return io->entries;
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io->count = io->entries;
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io->urbs = kmalloc (io->entries * sizeof *io->urbs, mem_flags);
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if (!io->urbs)
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goto nomem;
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urb_flags = URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT;
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if (usb_pipein (pipe))
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urb_flags |= URB_SHORT_NOT_OK;
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for (i = 0; i < io->entries; i++) {
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unsigned len;
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io->urbs [i] = usb_alloc_urb (0, mem_flags);
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if (!io->urbs [i]) {
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io->entries = i;
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goto nomem;
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}
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io->urbs [i]->dev = NULL;
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io->urbs [i]->pipe = pipe;
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io->urbs [i]->interval = period;
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io->urbs [i]->transfer_flags = urb_flags;
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io->urbs [i]->complete = sg_complete;
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io->urbs [i]->context = io;
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io->urbs [i]->status = -EINPROGRESS;
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io->urbs [i]->actual_length = 0;
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if (dma) {
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/* hc may use _only_ transfer_dma */
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io->urbs [i]->transfer_dma = sg_dma_address (sg + i);
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len = sg_dma_len (sg + i);
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} else {
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/* hc may use _only_ transfer_buffer */
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io->urbs [i]->transfer_buffer =
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page_address (sg [i].page) + sg [i].offset;
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len = sg [i].length;
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}
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if (length) {
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len = min_t (unsigned, len, length);
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length -= len;
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if (length == 0)
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io->entries = i + 1;
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}
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io->urbs [i]->transfer_buffer_length = len;
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}
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io->urbs [--i]->transfer_flags &= ~URB_NO_INTERRUPT;
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/* transaction state */
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io->status = 0;
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io->bytes = 0;
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init_completion (&io->complete);
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return 0;
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nomem:
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sg_clean (io);
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return -ENOMEM;
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}
|
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|
|
|
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/**
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* usb_sg_wait - synchronously execute scatter/gather request
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* @io: request block handle, as initialized with usb_sg_init().
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* some fields become accessible when this call returns.
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* Context: !in_interrupt ()
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*
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* This function blocks until the specified I/O operation completes. It
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* leverages the grouping of the related I/O requests to get good transfer
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* rates, by queueing the requests. At higher speeds, such queuing can
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* significantly improve USB throughput.
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*
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* There are three kinds of completion for this function.
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* (1) success, where io->status is zero. The number of io->bytes
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* transferred is as requested.
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* (2) error, where io->status is a negative errno value. The number
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* of io->bytes transferred before the error is usually less
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* than requested, and can be nonzero.
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* (3) cancellation, a type of error with status -ECONNRESET that
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* is initiated by usb_sg_cancel().
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*
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* When this function returns, all memory allocated through usb_sg_init() or
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* this call will have been freed. The request block parameter may still be
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* passed to usb_sg_cancel(), or it may be freed. It could also be
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* reinitialized and then reused.
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*
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* Data Transfer Rates:
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*
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* Bulk transfers are valid for full or high speed endpoints.
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* The best full speed data rate is 19 packets of 64 bytes each
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* per frame, or 1216 bytes per millisecond.
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* The best high speed data rate is 13 packets of 512 bytes each
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* per microframe, or 52 KBytes per millisecond.
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*
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* The reason to use interrupt transfers through this API would most likely
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* be to reserve high speed bandwidth, where up to 24 KBytes per millisecond
|
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* could be transferred. That capability is less useful for low or full
|
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* speed interrupt endpoints, which allow at most one packet per millisecond,
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|
* of at most 8 or 64 bytes (respectively).
|
|
*/
|
|
void usb_sg_wait (struct usb_sg_request *io)
|
|
{
|
|
int i, entries = io->entries;
|
|
|
|
/* queue the urbs. */
|
|
spin_lock_irq (&io->lock);
|
|
for (i = 0; i < entries && !io->status; i++) {
|
|
int retval;
|
|
|
|
io->urbs [i]->dev = io->dev;
|
|
retval = usb_submit_urb (io->urbs [i], SLAB_ATOMIC);
|
|
|
|
/* after we submit, let completions or cancelations fire;
|
|
* we handshake using io->status.
|
|
*/
|
|
spin_unlock_irq (&io->lock);
|
|
switch (retval) {
|
|
/* maybe we retrying will recover */
|
|
case -ENXIO: // hc didn't queue this one
|
|
case -EAGAIN:
|
|
case -ENOMEM:
|
|
io->urbs[i]->dev = NULL;
|
|
retval = 0;
|
|
i--;
|
|
yield ();
|
|
break;
|
|
|
|
/* no error? continue immediately.
|
|
*
|
|
* NOTE: to work better with UHCI (4K I/O buffer may
|
|
* need 3K of TDs) it may be good to limit how many
|
|
* URBs are queued at once; N milliseconds?
|
|
*/
|
|
case 0:
|
|
cpu_relax ();
|
|
break;
|
|
|
|
/* fail any uncompleted urbs */
|
|
default:
|
|
io->urbs [i]->dev = NULL;
|
|
io->urbs [i]->status = retval;
|
|
dev_dbg (&io->dev->dev, "%s, submit --> %d\n",
|
|
__FUNCTION__, retval);
|
|
usb_sg_cancel (io);
|
|
}
|
|
spin_lock_irq (&io->lock);
|
|
if (retval && (io->status == 0 || io->status == -ECONNRESET))
|
|
io->status = retval;
|
|
}
|
|
io->count -= entries - i;
|
|
if (io->count == 0)
|
|
complete (&io->complete);
|
|
spin_unlock_irq (&io->lock);
|
|
|
|
/* OK, yes, this could be packaged as non-blocking.
|
|
* So could the submit loop above ... but it's easier to
|
|
* solve neither problem than to solve both!
|
|
*/
|
|
wait_for_completion (&io->complete);
|
|
|
|
sg_clean (io);
|
|
}
|
|
|
|
/**
|
|
* usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait()
|
|
* @io: request block, initialized with usb_sg_init()
|
|
*
|
|
* This stops a request after it has been started by usb_sg_wait().
|
|
* It can also prevents one initialized by usb_sg_init() from starting,
|
|
* so that call just frees resources allocated to the request.
|
|
*/
|
|
void usb_sg_cancel (struct usb_sg_request *io)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave (&io->lock, flags);
|
|
|
|
/* shut everything down, if it didn't already */
|
|
if (!io->status) {
|
|
int i;
|
|
|
|
io->status = -ECONNRESET;
|
|
spin_unlock (&io->lock);
|
|
for (i = 0; i < io->entries; i++) {
|
|
int retval;
|
|
|
|
if (!io->urbs [i]->dev)
|
|
continue;
|
|
retval = usb_unlink_urb (io->urbs [i]);
|
|
if (retval != -EINPROGRESS && retval != -EBUSY)
|
|
dev_warn (&io->dev->dev, "%s, unlink --> %d\n",
|
|
__FUNCTION__, retval);
|
|
}
|
|
spin_lock (&io->lock);
|
|
}
|
|
spin_unlock_irqrestore (&io->lock, flags);
|
|
}
|
|
|
|
/*-------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* usb_get_descriptor - issues a generic GET_DESCRIPTOR request
|
|
* @dev: the device whose descriptor is being retrieved
|
|
* @type: the descriptor type (USB_DT_*)
|
|
* @index: the number of the descriptor
|
|
* @buf: where to put the descriptor
|
|
* @size: how big is "buf"?
|
|
* Context: !in_interrupt ()
|
|
*
|
|
* Gets a USB descriptor. Convenience functions exist to simplify
|
|
* getting some types of descriptors. Use
|
|
* 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
|
|
* devices also use class-specific or vendor-specific descriptors.
|
|
*
|
|
* This call is synchronous, and may not be used in an interrupt context.
|
|
*
|
|
* Returns the number of bytes received on success, or else the status code
|
|
* returned by the underlying usb_control_msg() call.
|
|
*/
|
|
int usb_get_descriptor(struct usb_device *dev, unsigned char type, unsigned char index, void *buf, int size)
|
|
{
|
|
int i;
|
|
int result;
|
|
|
|
memset(buf,0,size); // Make sure we parse really received data
|
|
|
|
for (i = 0; i < 3; ++i) {
|
|
/* retry on length 0 or stall; some devices are flakey */
|
|
result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
|
|
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
|
|
(type << 8) + index, 0, buf, size,
|
|
USB_CTRL_GET_TIMEOUT);
|
|
if (result == 0 || result == -EPIPE)
|
|
continue;
|
|
if (result > 1 && ((u8 *)buf)[1] != type) {
|
|
result = -EPROTO;
|
|
continue;
|
|
}
|
|
break;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* usb_get_string - gets a string descriptor
|
|
* @dev: the device whose string descriptor is being retrieved
|
|
* @langid: code for language chosen (from string descriptor zero)
|
|
* @index: the number of the descriptor
|
|
* @buf: where to put the string
|
|
* @size: how big is "buf"?
|
|
* Context: !in_interrupt ()
|
|
*
|
|
* Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per character,
|
|
* in little-endian byte order).
|
|
* The usb_string() function will often be a convenient way to turn
|
|
* these strings into kernel-printable form.
|
|
*
|
|
* Strings may be referenced in device, configuration, interface, or other
|
|
* descriptors, and could also be used in vendor-specific ways.
|
|
*
|
|
* This call is synchronous, and may not be used in an interrupt context.
|
|
*
|
|
* Returns the number of bytes received on success, or else the status code
|
|
* returned by the underlying usb_control_msg() call.
|
|
*/
|
|
static int usb_get_string(struct usb_device *dev, unsigned short langid,
|
|
unsigned char index, void *buf, int size)
|
|
{
|
|
int i;
|
|
int result;
|
|
|
|
for (i = 0; i < 3; ++i) {
|
|
/* retry on length 0 or stall; some devices are flakey */
|
|
result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
|
|
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
|
|
(USB_DT_STRING << 8) + index, langid, buf, size,
|
|
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)
|
|
{
|
|
int rc;
|
|
|
|
/* Try to read the string descriptor by asking for the maximum
|
|
* possible number of bytes */
|
|
rc = usb_get_string(dev, langid, index, buf, 255);
|
|
|
|
/* If that failed try to read the descriptor length, then
|
|
* ask for just that many bytes */
|
|
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 >= 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];
|
|
|
|
rc = rc - (rc & 1); /* force a multiple of two */
|
|
}
|
|
|
|
if (rc < 2)
|
|
rc = (rc < 0 ? rc : -EINVAL);
|
|
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* usb_string - returns ISO 8859-1 version of a string descriptor
|
|
* @dev: the device whose string descriptor is being retrieved
|
|
* @index: the number of the descriptor
|
|
* @buf: where to put the string
|
|
* @size: how big is "buf"?
|
|
* Context: !in_interrupt ()
|
|
*
|
|
* This converts the UTF-16LE encoded strings returned by devices, from
|
|
* usb_get_string_descriptor(), to null-terminated ISO-8859-1 encoded ones
|
|
* that are more usable in most kernel contexts. Note that all characters
|
|
* in the chosen descriptor that can't be encoded using ISO-8859-1
|
|
* are converted to the question mark ("?") character, and this function
|
|
* chooses strings in the first language supported by the device.
|
|
*
|
|
* The ASCII (or, redundantly, "US-ASCII") character set is the seven-bit
|
|
* subset of ISO 8859-1. ISO-8859-1 is the eight-bit subset of Unicode,
|
|
* and is appropriate for use many uses of English and several other
|
|
* Western European languages. (But it doesn't include the "Euro" symbol.)
|
|
*
|
|
* This call is synchronous, and may not be used in an interrupt context.
|
|
*
|
|
* Returns length of the string (>= 0) or usb_control_msg status (< 0).
|
|
*/
|
|
int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
|
|
{
|
|
unsigned char *tbuf;
|
|
int err;
|
|
unsigned int u, idx;
|
|
|
|
if (dev->state == USB_STATE_SUSPENDED)
|
|
return -EHOSTUNREACH;
|
|
if (size <= 0 || !buf || !index)
|
|
return -EINVAL;
|
|
buf[0] = 0;
|
|
tbuf = kmalloc(256, GFP_KERNEL);
|
|
if (!tbuf)
|
|
return -ENOMEM;
|
|
|
|
/* get langid for strings if it's not yet known */
|
|
if (!dev->have_langid) {
|
|
err = usb_string_sub(dev, 0, 0, tbuf);
|
|
if (err < 0) {
|
|
dev_err (&dev->dev,
|
|
"string descriptor 0 read error: %d\n",
|
|
err);
|
|
goto errout;
|
|
} else if (err < 4) {
|
|
dev_err (&dev->dev, "string descriptor 0 too short\n");
|
|
err = -EINVAL;
|
|
goto errout;
|
|
} else {
|
|
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",
|
|
dev->string_langid);
|
|
}
|
|
}
|
|
|
|
err = usb_string_sub(dev, dev->string_langid, index, tbuf);
|
|
if (err < 0)
|
|
goto errout;
|
|
|
|
size--; /* leave room for trailing NULL char in output buffer */
|
|
for (idx = 0, u = 2; u < err; u += 2) {
|
|
if (idx >= size)
|
|
break;
|
|
if (tbuf[u+1]) /* high byte */
|
|
buf[idx++] = '?'; /* non ISO-8859-1 character */
|
|
else
|
|
buf[idx++] = tbuf[u];
|
|
}
|
|
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_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.
|
|
*
|
|
* 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
|
|
* type = USB_DT_DEVICE and index = 0.
|
|
*
|
|
* This call is synchronous, and may not be used in an interrupt context.
|
|
*
|
|
* Returns the number of bytes received on success, or else the status code
|
|
* returned by the underlying usb_control_msg() call.
|
|
*/
|
|
int usb_get_device_descriptor(struct usb_device *dev, unsigned int size)
|
|
{
|
|
struct usb_device_descriptor *desc;
|
|
int ret;
|
|
|
|
if (size > sizeof(*desc))
|
|
return -EINVAL;
|
|
desc = kmalloc(sizeof(*desc), GFP_NOIO);
|
|
if (!desc)
|
|
return -ENOMEM;
|
|
|
|
ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size);
|
|
if (ret >= 0)
|
|
memcpy(&dev->descriptor, desc, size);
|
|
kfree(desc);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* usb_get_status - issues a GET_STATUS call
|
|
* @dev: the device whose status is being checked
|
|
* @type: USB_RECIP_*; for device, interface, or endpoint
|
|
* @target: zero (for device), else interface or endpoint number
|
|
* @data: pointer to two bytes of bitmap data
|
|
* Context: !in_interrupt ()
|
|
*
|
|
* Returns device, interface, or endpoint status. Normally only of
|
|
* interest to see if the device is self powered, or has enabled the
|
|
* remote wakeup facility; or whether a bulk or interrupt endpoint
|
|
* is halted ("stalled").
|
|
*
|
|
* Bits in these status bitmaps are set using the SET_FEATURE request,
|
|
* and cleared using the CLEAR_FEATURE request. The usb_clear_halt()
|
|
* function should be used to clear halt ("stall") status.
|
|
*
|
|
* This call is synchronous, and may not be used in an interrupt context.
|
|
*
|
|
* Returns the number of bytes received on success, or else the status code
|
|
* returned by the underlying usb_control_msg() call.
|
|
*/
|
|
int usb_get_status(struct usb_device *dev, int type, int target, void *data)
|
|
{
|
|
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;
|
|
}
|
|
|
|
/**
|
|
* usb_clear_halt - tells device to clear endpoint halt/stall condition
|
|
* @dev: device whose endpoint is halted
|
|
* @pipe: endpoint "pipe" being cleared
|
|
* Context: !in_interrupt ()
|
|
*
|
|
* This is used to clear halt conditions for bulk and interrupt endpoints,
|
|
* as reported by URB completion status. Endpoints that are halted are
|
|
* sometimes referred to as being "stalled". Such endpoints are unable
|
|
* to transmit or receive data until the halt status is cleared. Any URBs
|
|
* queued for such an endpoint should normally be unlinked by the driver
|
|
* before clearing the halt condition, as described in sections 5.7.5
|
|
* and 5.8.5 of the USB 2.0 spec.
|
|
*
|
|
* Note that control and isochronous endpoints don't halt, although control
|
|
* endpoints report "protocol stall" (for unsupported requests) using the
|
|
* same status code used to report a true stall.
|
|
*
|
|
* This call is synchronous, and may not be used in an interrupt context.
|
|
*
|
|
* Returns zero on success, or else the status code returned by the
|
|
* underlying usb_control_msg() call.
|
|
*/
|
|
int usb_clear_halt(struct usb_device *dev, int pipe)
|
|
{
|
|
int result;
|
|
int endp = usb_pipeendpoint(pipe);
|
|
|
|
if (usb_pipein (pipe))
|
|
endp |= USB_DIR_IN;
|
|
|
|
/* we don't care if it wasn't halted first. in fact some devices
|
|
* (like some ibmcam model 1 units) seem to expect hosts to make
|
|
* this request for iso endpoints, which can't halt!
|
|
*/
|
|
result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
|
|
USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
|
|
USB_ENDPOINT_HALT, endp, NULL, 0,
|
|
USB_CTRL_SET_TIMEOUT);
|
|
|
|
/* don't un-halt or force to DATA0 except on success */
|
|
if (result < 0)
|
|
return result;
|
|
|
|
/* NOTE: seems like Microsoft and Apple don't bother verifying
|
|
* the clear "took", so some devices could lock up if you check...
|
|
* such as the Hagiwara FlashGate DUAL. So we won't bother.
|
|
*
|
|
* NOTE: make sure the logic here doesn't diverge much from
|
|
* the copy in usb-storage, for as long as we need two copies.
|
|
*/
|
|
|
|
/* toggle was reset by the clear */
|
|
usb_settoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* usb_disable_endpoint -- Disable an endpoint by address
|
|
* @dev: the device whose endpoint is being disabled
|
|
* @epaddr: the endpoint's address. Endpoint number for output,
|
|
* endpoint number + USB_DIR_IN for input
|
|
*
|
|
* Deallocates hcd/hardware state for this endpoint ... and nukes all
|
|
* pending urbs.
|
|
*
|
|
* If the HCD hasn't registered a disable() function, this sets the
|
|
* endpoint's maxpacket size to 0 to prevent further submissions.
|
|
*/
|
|
void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr)
|
|
{
|
|
unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
|
|
struct usb_host_endpoint *ep;
|
|
|
|
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 && dev->bus->op && dev->bus->op->disable)
|
|
dev->bus->op->disable(dev, ep);
|
|
}
|
|
|
|
/**
|
|
* usb_disable_interface -- Disable all endpoints for an interface
|
|
* @dev: the device whose interface is being disabled
|
|
* @intf: pointer to the interface descriptor
|
|
*
|
|
* Disables all the endpoints for the interface's current altsetting.
|
|
*/
|
|
void usb_disable_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_disable_endpoint(dev,
|
|
alt->endpoint[i].desc.bEndpointAddress);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* usb_disable_device - Disable all the endpoints for a USB device
|
|
* @dev: the device whose endpoints are being disabled
|
|
* @skip_ep0: 0 to disable endpoint 0, 1 to skip it.
|
|
*
|
|
* Disables all the device's endpoints, potentially including endpoint 0.
|
|
* Deallocates hcd/hardware state for the endpoints (nuking all or most
|
|
* pending urbs) and usbcore state for the interfaces, so that usbcore
|
|
* must usb_set_configuration() before any interfaces could be used.
|
|
*/
|
|
void usb_disable_device(struct usb_device *dev, int skip_ep0)
|
|
{
|
|
int i;
|
|
|
|
dev_dbg(&dev->dev, "%s nuking %s URBs\n", __FUNCTION__,
|
|
skip_ep0 ? "non-ep0" : "all");
|
|
for (i = skip_ep0; i < 16; ++i) {
|
|
usb_disable_endpoint(dev, i);
|
|
usb_disable_endpoint(dev, i + USB_DIR_IN);
|
|
}
|
|
dev->toggle[0] = dev->toggle[1] = 0;
|
|
|
|
/* getting rid of interfaces will disconnect
|
|
* any drivers bound to them (a key side effect)
|
|
*/
|
|
if (dev->actconfig) {
|
|
for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
|
|
struct usb_interface *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);
|
|
device_del (&interface->dev);
|
|
}
|
|
|
|
/* Now that the interfaces are unbound, nobody should
|
|
* try to access them.
|
|
*/
|
|
for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
|
|
put_device (&dev->actconfig->interface[i]->dev);
|
|
dev->actconfig->interface[i] = NULL;
|
|
}
|
|
dev->actconfig = NULL;
|
|
if (dev->state == USB_STATE_CONFIGURED)
|
|
usb_set_device_state(dev, USB_STATE_ADDRESS);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* usb_enable_endpoint - Enable an endpoint for USB communications
|
|
* @dev: the device whose interface is being enabled
|
|
* @ep: the endpoint
|
|
*
|
|
* Resets the endpoint toggle, and sets dev->ep_{in,out} pointers.
|
|
* For control endpoints, both the input and output sides are handled.
|
|
*/
|
|
static void
|
|
usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep)
|
|
{
|
|
unsigned int epaddr = ep->desc.bEndpointAddress;
|
|
unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
|
|
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->ep_out[epnum] = ep;
|
|
}
|
|
if (!usb_endpoint_out(epaddr) || is_control) {
|
|
usb_settoggle(dev, epnum, 0, 0);
|
|
dev->ep_in[epnum] = ep;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* usb_enable_interface - Enable all the endpoints for an interface
|
|
* @dev: the device whose interface is being enabled
|
|
* @intf: pointer to the interface descriptor
|
|
*
|
|
* Enables all the endpoints for the interface's current altsetting.
|
|
*/
|
|
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]);
|
|
}
|
|
|
|
/**
|
|
* usb_set_interface - Makes a particular alternate setting be current
|
|
* @dev: the device whose interface is being updated
|
|
* @interface: the interface being updated
|
|
* @alternate: the setting being chosen.
|
|
* Context: !in_interrupt ()
|
|
*
|
|
* This is used to enable data transfers on interfaces that may not
|
|
* be enabled by default. Not all devices support such configurability.
|
|
* Only the driver bound to an interface may change its setting.
|
|
*
|
|
* Within any given configuration, each interface may have several
|
|
* alternative settings. These are often used to control levels of
|
|
* bandwidth consumption. For example, the default setting for a high
|
|
* speed interrupt endpoint may not send more than 64 bytes per microframe,
|
|
* while interrupt transfers of up to 3KBytes per microframe are legal.
|
|
* Also, isochronous endpoints may never be part of an
|
|
* interface's default setting. To access such bandwidth, alternate
|
|
* interface settings must be made current.
|
|
*
|
|
* Note that in the Linux USB subsystem, bandwidth associated with
|
|
* an endpoint in a given alternate setting is not reserved until an URB
|
|
* is submitted that needs that bandwidth. Some other operating systems
|
|
* allocate bandwidth early, when a configuration is chosen.
|
|
*
|
|
* This call is synchronous, and may not be used in an interrupt context.
|
|
* Also, drivers must not change altsettings while urbs are scheduled for
|
|
* endpoints in that interface; all such urbs must first be completed
|
|
* (perhaps forced by unlinking).
|
|
*
|
|
* Returns zero on success, or else the status code returned by the
|
|
* underlying usb_control_msg() call.
|
|
*/
|
|
int usb_set_interface(struct usb_device *dev, int interface, int alternate)
|
|
{
|
|
struct usb_interface *iface;
|
|
struct usb_host_interface *alt;
|
|
int ret;
|
|
int manual = 0;
|
|
|
|
if (dev->state == USB_STATE_SUSPENDED)
|
|
return -EHOSTUNREACH;
|
|
|
|
iface = usb_ifnum_to_if(dev, interface);
|
|
if (!iface) {
|
|
dev_dbg(&dev->dev, "selecting invalid interface %d\n",
|
|
interface);
|
|
return -EINVAL;
|
|
}
|
|
|
|
alt = usb_altnum_to_altsetting(iface, alternate);
|
|
if (!alt) {
|
|
warn("selecting invalid altsetting %d", alternate);
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
|
|
USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
|
|
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.
|
|
*/
|
|
if (ret == -EPIPE && iface->num_altsetting == 1) {
|
|
dev_dbg(&dev->dev,
|
|
"manual set_interface for iface %d, alt %d\n",
|
|
interface, alternate);
|
|
manual = 1;
|
|
} else if (ret < 0)
|
|
return ret;
|
|
|
|
/* FIXME drivers shouldn't need to replicate/bugfix the logic here
|
|
* when they implement async or easily-killable versions of this or
|
|
* other "should-be-internal" functions (like clear_halt).
|
|
* should hcd+usbcore postprocess control requests?
|
|
*/
|
|
|
|
/* 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;
|
|
|
|
/* If the interface only has one altsetting and the device didn't
|
|
* accept the request, we attempt to carry out the equivalent action
|
|
* by manually clearing the HALT feature for each endpoint in the
|
|
* new altsetting.
|
|
*/
|
|
if (manual) {
|
|
int i;
|
|
|
|
for (i = 0; i < alt->desc.bNumEndpoints; i++) {
|
|
unsigned int epaddr =
|
|
alt->endpoint[i].desc.bEndpointAddress;
|
|
unsigned int pipe =
|
|
__create_pipe(dev, USB_ENDPOINT_NUMBER_MASK & epaddr)
|
|
| (usb_endpoint_out(epaddr) ? USB_DIR_OUT : USB_DIR_IN);
|
|
|
|
usb_clear_halt(dev, pipe);
|
|
}
|
|
}
|
|
|
|
/* 9.1.1.5: reset toggles for all endpoints in the new altsetting
|
|
*
|
|
* Note:
|
|
* Despite EP0 is always present in all interfaces/AS, the list of
|
|
* endpoints from the descriptor does not contain EP0. Due to its
|
|
* omnipresence one might expect EP0 being considered "affected" by
|
|
* any SetInterface request and hence assume toggles need to be reset.
|
|
* However, EP0 toggles are re-synced for every individual transfer
|
|
* during the SETUP stage - hence EP0 toggles are "don't care" here.
|
|
* (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;
|
|
}
|
|
|
|
/**
|
|
* usb_reset_configuration - lightweight device reset
|
|
* @dev: the device whose configuration is being reset
|
|
*
|
|
* This issues a standard SET_CONFIGURATION request to the device using
|
|
* the current configuration. The effect is to reset most USB-related
|
|
* state in the device, including interface altsettings (reset to zero),
|
|
* endpoint halts (cleared), and data toggle (only for bulk and interrupt
|
|
* endpoints). Other usbcore state is unchanged, including bindings of
|
|
* usb device drivers to interfaces.
|
|
*
|
|
* 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. 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)
|
|
{
|
|
int i, retval;
|
|
struct usb_host_config *config;
|
|
|
|
if (dev->state == USB_STATE_SUSPENDED)
|
|
return -EHOSTUNREACH;
|
|
|
|
/* 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) {
|
|
usb_disable_endpoint(dev, i);
|
|
usb_disable_endpoint(dev, i + USB_DIR_IN);
|
|
}
|
|
|
|
config = dev->actconfig;
|
|
retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
|
|
USB_REQ_SET_CONFIGURATION, 0,
|
|
config->desc.bConfigurationValue, 0,
|
|
NULL, 0, USB_CTRL_SET_TIMEOUT);
|
|
if (retval < 0)
|
|
return retval;
|
|
|
|
dev->toggle[0] = dev->toggle[1] = 0;
|
|
|
|
/* re-init hc/hcd interface/endpoint state */
|
|
for (i = 0; i < config->desc.bNumInterfaces; i++) {
|
|
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.
|
|
* 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);
|
|
if (device_is_registered(&intf->dev))
|
|
usb_create_sysfs_intf_files(intf);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void release_interface(struct device *dev)
|
|
{
|
|
struct usb_interface *intf = to_usb_interface(dev);
|
|
struct usb_interface_cache *intfc =
|
|
altsetting_to_usb_interface_cache(intf->altsetting);
|
|
|
|
kref_put(&intfc->ref, usb_release_interface_cache);
|
|
kfree(intf);
|
|
}
|
|
|
|
/*
|
|
* 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 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
|
|
* configuration.
|
|
*
|
|
* USB device configurations may affect Linux interoperability,
|
|
* power consumption and the functionality available. For example,
|
|
* the default configuration is limited to using 100mA of bus power,
|
|
* so that when certain device functionality requires more power,
|
|
* and the device is bus powered, that functionality should be in some
|
|
* non-default device configuration. Other device modes may also be
|
|
* reflected as configuration options, such as whether two ISDN
|
|
* channels are available independently; and choosing between open
|
|
* standard device protocols (like CDC) or proprietary ones.
|
|
*
|
|
* Note that USB has an additional level of device configurability,
|
|
* associated with interfaces. That configurability is accessed using
|
|
* usb_set_interface().
|
|
*
|
|
* This call is synchronous. The calling context must be able to sleep,
|
|
* 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 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.
|
|
*/
|
|
int usb_set_configuration(struct usb_device *dev, int configuration)
|
|
{
|
|
int i, ret;
|
|
struct usb_host_config *cp = NULL;
|
|
struct usb_interface **new_interfaces = NULL;
|
|
int n, nintf;
|
|
|
|
for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
|
|
if (dev->config[i].desc.bConfigurationValue == configuration) {
|
|
cp = &dev->config[i];
|
|
break;
|
|
}
|
|
}
|
|
if ((!cp && configuration != 0))
|
|
return -EINVAL;
|
|
|
|
/* The USB spec says configuration 0 means unconfigured.
|
|
* But if a device includes a configuration numbered 0,
|
|
* we will accept it as a correctly configured state.
|
|
*/
|
|
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;
|
|
if (cp) {
|
|
nintf = cp->desc.bNumInterfaces;
|
|
new_interfaces = kmalloc(nintf * sizeof(*new_interfaces),
|
|
GFP_KERNEL);
|
|
if (!new_interfaces) {
|
|
dev_err(&dev->dev, "Out of memory");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
for (; n < nintf; ++n) {
|
|
new_interfaces[n] = kzalloc(
|
|
sizeof(struct usb_interface),
|
|
GFP_KERNEL);
|
|
if (!new_interfaces[n]) {
|
|
dev_err(&dev->dev, "Out of memory");
|
|
ret = -ENOMEM;
|
|
free_interfaces:
|
|
while (--n >= 0)
|
|
kfree(new_interfaces[n]);
|
|
kfree(new_interfaces);
|
|
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);
|
|
}
|
|
|
|
/* if it's already configured, clear out old state first.
|
|
* getting rid of old interfaces means unbinding their drivers.
|
|
*/
|
|
if (dev->state != USB_STATE_ADDRESS)
|
|
usb_disable_device (dev, 1); // Skip ep0
|
|
|
|
if ((ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
|
|
USB_REQ_SET_CONFIGURATION, 0, configuration, 0,
|
|
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) {
|
|
usb_set_device_state(dev, USB_STATE_ADDRESS);
|
|
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];
|
|
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);
|
|
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 0;
|
|
}
|
|
|
|
// synchronous request completion model
|
|
EXPORT_SYMBOL(usb_control_msg);
|
|
EXPORT_SYMBOL(usb_bulk_msg);
|
|
|
|
EXPORT_SYMBOL(usb_sg_init);
|
|
EXPORT_SYMBOL(usb_sg_cancel);
|
|
EXPORT_SYMBOL(usb_sg_wait);
|
|
|
|
// synchronous control message convenience routines
|
|
EXPORT_SYMBOL(usb_get_descriptor);
|
|
EXPORT_SYMBOL(usb_get_status);
|
|
EXPORT_SYMBOL(usb_string);
|
|
|
|
// synchronous calls that also maintain usbcore state
|
|
EXPORT_SYMBOL(usb_clear_halt);
|
|
EXPORT_SYMBOL(usb_reset_configuration);
|
|
EXPORT_SYMBOL(usb_set_interface);
|
|
|