zd_usb.c

linux内核源码

		goto error_free_urb;
	}
	intr->urb = urb;
	spin_unlock_irq(&intr->lock);

	/* TODO: make it a DMA buffer */
	r = -ENOMEM;
	transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_KERNEL);
	if (!transfer_buffer) {
		dev_dbg_f(zd_usb_dev(usb),
			"couldn't allocate transfer_buffer\n");
		goto error_set_urb_null;
	}

	udev = zd_usb_to_usbdev(usb);
	usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
			 transfer_buffer, USB_MAX_EP_INT_BUFFER,
			 int_urb_complete, usb,
			 intr->interval);

	dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
	r = usb_submit_urb(urb, GFP_KERNEL);
	if (r) {
		dev_dbg_f(zd_usb_dev(usb),
			 "Couldn't submit urb. Error number %d\n", r);
		goto error;
	}

	return 0;
error:
	kfree(transfer_buffer);
error_set_urb_null:
	spin_lock_irq(&intr->lock);
	intr->urb = NULL;
	spin_unlock_irq(&intr->lock);
error_free_urb:
	usb_free_urb(urb);
out:
	return r;
}

void zd_usb_disable_int(struct zd_usb *usb)
{
	unsigned long flags;
	struct zd_usb_interrupt *intr = &usb->intr;
	struct urb *urb;

	spin_lock_irqsave(&intr->lock, flags);
	urb = intr->urb;
	if (!urb) {
		spin_unlock_irqrestore(&intr->lock, flags);
		return;
	}
	intr->urb = NULL;
	spin_unlock_irqrestore(&intr->lock, flags);

	usb_kill_urb(urb);
	dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
	usb_free_urb(urb);
}

static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
			     unsigned int length)
{
	int i;
	struct zd_mac *mac = zd_usb_to_mac(usb);
	const struct rx_length_info *length_info;

	if (length < sizeof(struct rx_length_info)) {
		/* It's not a complete packet anyhow. */
		struct ieee80211_device *ieee = zd_mac_to_ieee80211(mac);
		ieee->stats.rx_errors++;
		ieee->stats.rx_length_errors++;
		return;
	}
	length_info = (struct rx_length_info *)
		(buffer + length - sizeof(struct rx_length_info));

	/* It might be that three frames are merged into a single URB
	 * transaction. We have to check for the length info tag.
	 *
	 * While testing we discovered that length_info might be unaligned,
	 * because if USB transactions are merged, the last packet will not
	 * be padded. Unaligned access might also happen if the length_info
	 * structure is not present.
	 */
	if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
	{
		unsigned int l, k, n;
		for (i = 0, l = 0;; i++) {
			k = le16_to_cpu(get_unaligned(&length_info->length[i]));
			if (k == 0)
				return;
			n = l+k;
			if (n > length)
				return;
			zd_mac_rx_irq(mac, buffer+l, k);
			if (i >= 2)
				return;
			l = (n+3) & ~3;
		}
	} else {
		zd_mac_rx_irq(mac, buffer, length);
	}
}

static void rx_urb_complete(struct urb *urb)
{
	struct zd_usb *usb;
	struct zd_usb_rx *rx;
	const u8 *buffer;
	unsigned int length;

	switch (urb->status) {
	case 0:
		break;
	case -ESHUTDOWN:
	case -EINVAL:
	case -ENODEV:
	case -ENOENT:
	case -ECONNRESET:
	case -EPIPE:
		return;
	default:
		dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
		goto resubmit;
	}

	buffer = urb->transfer_buffer;
	length = urb->actual_length;
	usb = urb->context;
	rx = &usb->rx;

	if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
		/* If there is an old first fragment, we don't care. */
		dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
		ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
		spin_lock(&rx->lock);
		memcpy(rx->fragment, buffer, length);
		rx->fragment_length = length;
		spin_unlock(&rx->lock);
		goto resubmit;
	}

	spin_lock(&rx->lock);
	if (rx->fragment_length > 0) {
		/* We are on a second fragment, we believe */
		ZD_ASSERT(length + rx->fragment_length <=
			  ARRAY_SIZE(rx->fragment));
		dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
		memcpy(rx->fragment+rx->fragment_length, buffer, length);
		handle_rx_packet(usb, rx->fragment,
			         rx->fragment_length + length);
		rx->fragment_length = 0;
		spin_unlock(&rx->lock);
	} else {
		spin_unlock(&rx->lock);
		handle_rx_packet(usb, buffer, length);
	}

resubmit:
	usb_submit_urb(urb, GFP_ATOMIC);
}

static struct urb *alloc_urb(struct zd_usb *usb)
{
	struct usb_device *udev = zd_usb_to_usbdev(usb);
	struct urb *urb;
	void *buffer;

	urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!urb)
		return NULL;
	buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
		                  &urb->transfer_dma);
	if (!buffer) {
		usb_free_urb(urb);
		return NULL;
	}

	usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
		          buffer, USB_MAX_RX_SIZE,
			  rx_urb_complete, usb);
	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

	return urb;
}

static void free_urb(struct urb *urb)
{
	if (!urb)
		return;
	usb_buffer_free(urb->dev, urb->transfer_buffer_length,
		        urb->transfer_buffer, urb->transfer_dma);
	usb_free_urb(urb);
}

int zd_usb_enable_rx(struct zd_usb *usb)
{
	int i, r;
	struct zd_usb_rx *rx = &usb->rx;
	struct urb **urbs;

	dev_dbg_f(zd_usb_dev(usb), "\n");

	r = -ENOMEM;
	urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_KERNEL);
	if (!urbs)
		goto error;
	for (i = 0; i < URBS_COUNT; i++) {
		urbs[i] = alloc_urb(usb);
		if (!urbs[i])
			goto error;
	}

	ZD_ASSERT(!irqs_disabled());
	spin_lock_irq(&rx->lock);
	if (rx->urbs) {
		spin_unlock_irq(&rx->lock);
		r = 0;
		goto error;
	}
	rx->urbs = urbs;
	rx->urbs_count = URBS_COUNT;
	spin_unlock_irq(&rx->lock);

	for (i = 0; i < URBS_COUNT; i++) {
		r = usb_submit_urb(urbs[i], GFP_KERNEL);
		if (r)
			goto error_submit;
	}

	return 0;
error_submit:
	for (i = 0; i < URBS_COUNT; i++) {
		usb_kill_urb(urbs[i]);
	}
	spin_lock_irq(&rx->lock);
	rx->urbs = NULL;
	rx->urbs_count = 0;
	spin_unlock_irq(&rx->lock);
error:
	if (urbs) {
		for (i = 0; i < URBS_COUNT; i++)
			free_urb(urbs[i]);
	}
	return r;
}

void zd_usb_disable_rx(struct zd_usb *usb)
{
	int i;
	unsigned long flags;
	struct urb **urbs;
	unsigned int count;
	struct zd_usb_rx *rx = &usb->rx;

	spin_lock_irqsave(&rx->lock, flags);
	urbs = rx->urbs;
	count = rx->urbs_count;
	spin_unlock_irqrestore(&rx->lock, flags);
	if (!urbs)
		return;

	for (i = 0; i < count; i++) {
		usb_kill_urb(urbs[i]);
		free_urb(urbs[i]);
	}
	kfree(urbs);

	spin_lock_irqsave(&rx->lock, flags);
	rx->urbs = NULL;
	rx->urbs_count = 0;
	spin_unlock_irqrestore(&rx->lock, flags);
}

static void tx_urb_complete(struct urb *urb)
{
	int r;

	switch (urb->status) {
	case 0:
		break;
	case -ESHUTDOWN:
	case -EINVAL:
	case -ENODEV:
	case -ENOENT:
	case -ECONNRESET:
	case -EPIPE:
		dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
		break;
	default:
		dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
		goto resubmit;
	}
free_urb:
	usb_buffer_free(urb->dev, urb->transfer_buffer_length,
		        urb->transfer_buffer, urb->transfer_dma);
	usb_free_urb(urb);
	return;
resubmit:
	r = usb_submit_urb(urb, GFP_ATOMIC);
	if (r) {
		dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
		goto free_urb;
	}
}

/* Puts the frame on the USB endpoint. It doesn't wait for
 * completion. The frame must contain the control set.
 */
int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
{
	int r;
	struct usb_device *udev = zd_usb_to_usbdev(usb);
	struct urb *urb;
	void *buffer;

	urb = usb_alloc_urb(0, GFP_ATOMIC);
	if (!urb) {
		r = -ENOMEM;
		goto out;
	}

	buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
		                  &urb->transfer_dma);
	if (!buffer) {
		r = -ENOMEM;
		goto error_free_urb;
	}
	memcpy(buffer, frame, length);

	usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
		          buffer, length, tx_urb_complete, NULL);
	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

	r = usb_submit_urb(urb, GFP_ATOMIC);
	if (r)
		goto error;
	return 0;
error:
	usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
		        urb->transfer_dma);
error_free_urb:
	usb_free_urb(urb);
out:
	return r;
}

static inline void init_usb_interrupt(struct zd_usb *usb)
{
	struct zd_usb_interrupt *intr = &usb->intr;

	spin_lock_init(&intr->lock);
	intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
	init_completion(&intr->read_regs.completion);
	intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
}

static inline void init_usb_rx(struct zd_usb *usb)
{
	struct zd_usb_rx *rx = &usb->rx;
	spin_lock_init(&rx->lock);
	if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
		rx->usb_packet_size = 512;
	} else {
		rx->usb_packet_size = 64;
	}
	ZD_ASSERT(rx->fragment_length == 0);
}

static inline void init_usb_tx(struct zd_usb *usb)
{
	/* FIXME: at this point we will allocate a fixed number of urb's for
	 * use in a cyclic scheme */
}

void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
	         struct usb_interface *intf)
{
	memset(usb, 0, sizeof(*usb));
	usb->intf = usb_get_intf(intf);
	usb_set_intfdata(usb->intf, netdev);
	init_usb_interrupt(usb);
	init_usb_tx(usb);
	init_usb_rx(usb);
}

void zd_usb_clear(struct zd_usb *usb)
{
	usb_set_intfdata(usb->intf, NULL);
	usb_put_intf(usb->intf);
	ZD_MEMCLEAR(usb, sizeof(*usb));
	/* FIXME: usb_interrupt, usb_tx, usb_rx? */
}

static const char *speed(enum usb_device_speed speed)
{
	switch (speed) {
	case USB_SPEED_LOW:
		return "low";
	case USB_SPEED_FULL:
		return "full";
	case USB_SPEED_HIGH:
		return "high";
	default:
		return "unknown speed";
	}
}

static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
{
	return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
		le16_to_cpu(udev->descriptor.idVendor),
		le16_to_cpu(udev->descriptor.idProduct),
		get_bcdDevice(udev),
		speed(udev->speed));
}

int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
{
	struct usb_device *udev = interface_to_usbdev(usb->intf);
	return scnprint_id(udev, buffer, size);
}

#ifdef DEBUG
static void print_id(struct usb_device *udev)
{
	char buffer[40];

	scnprint_id(udev, buffer, sizeof(buffer));
	buffer[sizeof(buffer)-1] = 0;
	dev_dbg_f(&udev->dev, "%s\n", buffer);
}
#else
#define print_id(udev) do { } while (0)
#endif

static int eject_installer(struct usb_interface *intf)
{
	struct usb_device *udev = interface_to_usbdev(intf);
	struct usb_host_interface *iface_desc = &intf->altsetting[0];
	struct usb_endpoint_descriptor *endpoint;
	unsigned char *cmd;
	u8 bulk_out_ep;
	int r;

	/* Find bulk out endpoint */
	endpoint = &iface_desc->endpoint[1].desc;
	if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
	    (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
	    USB_ENDPOINT_XFER_BULK) {
		bulk_out_ep = endpoint->bEndpointAddress;
	} else {
		dev_err(&udev->dev,
			"zd1211rw: Could not find bulk out endpoint\n");
		return -ENODEV;
	}

	cmd = kzalloc(31, GFP_KERNEL);
	if (cmd == NULL)
		return -ENODEV;

	/* USB bulk command block */
	cmd[0] = 0x55;	/* bulk command signature */
	cmd[1] = 0x53;	/* bulk command signature */
	cmd[2] = 0x42;	/* bulk command signature */