net2280.c

ARM S3C2410 USB SLAVE LINUX驱动

	/* basic endpoint init */
	for (tmp = 0; tmp < 7; tmp++) {
		struct net2280_ep	*ep = &dev->ep [tmp];

		ep->ep.name = ep_name [tmp];
		ep->dev = dev;
		ep->num = tmp;

		if (tmp > 0 && tmp <= 4) {
			ep->fifo_size = 1024;
			if (init_dma)
				ep->dma = &dev->dma [tmp - 1];
		} else
			ep->fifo_size = 64;
		ep->regs = &dev->epregs [tmp];
		ep_reset (dev->regs, ep);
	}
	dev->ep [0].ep.maxpacket = 64;
	dev->ep [5].ep.maxpacket = 64;
	dev->ep [6].ep.maxpacket = 64;

	dev->gadget.ep0 = &dev->ep [0].ep;
	dev->ep [0].stopped = 0;
	INIT_LIST_HEAD (&dev->gadget.ep0->ep_list);

	/* we want to prevent lowlevel/insecure access from the USB host,
	 * but erratum 0119 means this enable bit is ignored
	 */
	for (tmp = 0; tmp < 5; tmp++)
		writel (EP_DONTUSE, &dev->dep [tmp].dep_cfg);
}

static void ep0_start (struct net2280 *dev)
{
	writel (  (1 << CLEAR_EP_HIDE_STATUS_PHASE)
		| (1 << CLEAR_NAK_OUT_PACKETS)
		| (1 << CLEAR_CONTROL_STATUS_PHASE_HANDSHAKE)
		, &dev->epregs [0].ep_rsp);

	/*
	 * hardware optionally handles a bunch of standard requests
	 * that the API hides from drivers anyway.  have it do so.
	 * endpoint status/features are handled in software, to
	 * help pass tests for some dubious behavior.
	 */
	writel (  (1 << SET_TEST_MODE)
		| (1 << SET_ADDRESS)
		| (1 << DEVICE_SET_CLEAR_DEVICE_REMOTE_WAKEUP)
		| (1 << GET_DEVICE_STATUS)
		| (1 << GET_INTERFACE_STATUS)
		, &dev->usb->stdrsp);
	writel (  (1 << USB_ROOT_PORT_WAKEUP_ENABLE)
		| (1 << SELF_POWERED_USB_DEVICE)
		| (1 << REMOTE_WAKEUP_SUPPORT)
		| (dev->softconnect << USB_DETECT_ENABLE)
		| (1 << SELF_POWERED_STATUS)
		, &dev->usb->usbctl);

	/* enable irqs so we can see ep0 and general operation  */
	writel (  (1 << SETUP_PACKET_INTERRUPT_ENABLE)
		| (1 << ENDPOINT_0_INTERRUPT_ENABLE)
		, &dev->regs->pciirqenb0);
	writel (  (1 << PCI_INTERRUPT_ENABLE)
		| (1 << PCI_MASTER_ABORT_RECEIVED_INTERRUPT_ENABLE)
		| (1 << PCI_TARGET_ABORT_RECEIVED_INTERRUPT_ENABLE)
		| (1 << PCI_RETRY_ABORT_INTERRUPT_ENABLE)
		| (1 << VBUS_INTERRUPT_ENABLE)
		| (1 << ROOT_PORT_RESET_INTERRUPT_ENABLE)
		| (1 << SUSPEND_REQUEST_CHANGE_INTERRUPT_ENABLE)
		, &dev->regs->pciirqenb1);

	/* don't leave any writes posted */
	(void) readl (&dev->usb->usbctl);
}

/* when a driver is successfully registered, it will receive
 * control requests including set_configuration(), which enables
 * non-control requests.  then usb traffic follows until a
 * disconnect is reported.  then a host may connect again, or
 * the driver might get unbound.
 */
int usb_gadget_register_driver (struct usb_gadget_driver *driver)
{
	struct net2280		*dev = the_controller;
	int			retval;
	unsigned		i;

	/* insist on high speed support from the driver, since
	 * (dev->usb->xcvrdiag & FORCE_FULL_SPEED_MODE)
	 * "must not be used in normal operation"
	 */
	if (!driver
			|| driver->speed != USB_SPEED_HIGH
			|| !driver->bind
			|| !driver->unbind
			|| !driver->setup)
		return -EINVAL;
	if (!dev)
		return -ENODEV;
	if (dev->driver)
		return -EBUSY;

	for (i = 0; i < 7; i++)
		dev->ep [i].irqs = 0;

	/* hook up the driver ... */
	dev->softconnect = 1;
	driver->driver.bus = NULL;
	dev->driver = driver;
	dev->gadget.dev.driver = &driver->driver;
	retval = driver->bind (&dev->gadget);
	if (retval) {
		DEBUG (dev, "bind to driver %s --> %d\n",
				driver->driver.name, retval);
		dev->driver = NULL;
		dev->gadget.dev.driver = NULL;
		return retval;
	}

	device_create_file (&dev->pdev->dev, &dev_attr_function);
	device_create_file (&dev->pdev->dev, &dev_attr_queues);

	/* ... then enable host detection and ep0; and we're ready
	 * for set_configuration as well as eventual disconnect.
	 */
	net2280_led_active (dev, 1);
	ep0_start (dev);

	DEBUG (dev, "%s ready, usbctl %08x stdrsp %08x\n",
			driver->driver.name,
			readl (&dev->usb->usbctl),
			readl (&dev->usb->stdrsp));

	/* pci writes may still be posted */
	return 0;
}
EXPORT_SYMBOL (usb_gadget_register_driver);

static void
stop_activity (struct net2280 *dev, struct usb_gadget_driver *driver)
{
	int			i;

	/* don't disconnect if it's not connected */
	if (dev->gadget.speed == USB_SPEED_UNKNOWN)
		driver = NULL;

	/* stop hardware; prevent new request submissions;
	 * and kill any outstanding requests.
	 */
	usb_reset (dev);
	for (i = 0; i < 7; i++)
		nuke (&dev->ep [i]);

	/* report disconnect; the driver is already quiesced */
	if (driver) {
		spin_unlock (&dev->lock);
		driver->disconnect (&dev->gadget);
		spin_lock (&dev->lock);
	}

	usb_reinit (dev);
}

int usb_gadget_unregister_driver (struct usb_gadget_driver *driver)
{
	struct net2280	*dev = the_controller;
	unsigned long	flags;

	if (!dev)
		return -ENODEV;
	if (!driver || driver != dev->driver)
		return -EINVAL;

	spin_lock_irqsave (&dev->lock, flags);
	stop_activity (dev, driver);
	spin_unlock_irqrestore (&dev->lock, flags);

	net2280_pullup (&dev->gadget, 0);

	driver->unbind (&dev->gadget);
	dev->gadget.dev.driver = NULL;
	dev->driver = NULL;

	net2280_led_active (dev, 0);
	device_remove_file (&dev->pdev->dev, &dev_attr_function);
	device_remove_file (&dev->pdev->dev, &dev_attr_queues);

	DEBUG (dev, "unregistered driver '%s'\n", driver->driver.name);
	return 0;
}
EXPORT_SYMBOL (usb_gadget_unregister_driver);


/*-------------------------------------------------------------------------*/

/* handle ep0, ep-e, ep-f with 64 byte packets: packet per irq.
 * also works for dma-capable endpoints, in pio mode or just
 * to manually advance the queue after short OUT transfers.
 */
static void handle_ep_small (struct net2280_ep *ep)
{
	struct net2280_request	*req;
	u32			t;
	/* 0 error, 1 mid-data, 2 done */
	int			mode = 1;

	if (!list_empty (&ep->queue))
		req = list_entry (ep->queue.next,
			struct net2280_request, queue);
	else
		req = NULL;

	/* ack all, and handle what we care about */
	t = readl (&ep->regs->ep_stat);
	ep->irqs++;
#if 0
	VDEBUG (ep->dev, "%s ack ep_stat %08x, req %p\n",
			ep->ep.name, t, req ? &req->req : 0);
#endif
	writel (t & ~(1 << NAK_OUT_PACKETS), &ep->regs->ep_stat);

	/* for ep0, monitor token irqs to catch data stage length errors
	 * and to synchronize on status.
	 *
	 * also, to defer reporting of protocol stalls ... here's where
	 * data or status first appears, handling stalls here should never
	 * cause trouble on the host side..
	 *
	 * control requests could be slightly faster without token synch for
	 * status, but status can jam up that way.
	 */
	if (unlikely (ep->num == 0)) {
		if (ep->is_in) {
			/* status; stop NAKing */
			if (t & (1 << DATA_OUT_PING_TOKEN_INTERRUPT)) {
				if (ep->dev->protocol_stall) {
					ep->stopped = 1;
					set_halt (ep);
				}
				if (!req)
					allow_status (ep);
				mode = 2;
			/* reply to extra IN data tokens with a zlp */
			} else if (t & (1 << DATA_IN_TOKEN_INTERRUPT)) {
				if (ep->dev->protocol_stall) {
					ep->stopped = 1;
					set_halt (ep);
					mode = 2;
				} else if (!req && ep->stopped)
					write_fifo (ep, NULL);
			}
		} else {
			/* status; stop NAKing */
			if (t & (1 << DATA_IN_TOKEN_INTERRUPT)) {
				if (ep->dev->protocol_stall) {
					ep->stopped = 1;
					set_halt (ep);
				}
				mode = 2;
			/* an extra OUT token is an error */
			} else if (((t & (1 << DATA_OUT_PING_TOKEN_INTERRUPT))
					&& req
					&& req->req.actual == req->req.length)
					|| !req) {
				ep->dev->protocol_stall = 1;
				set_halt (ep);
				ep->stopped = 1;
				if (req)
					done (ep, req, -EOVERFLOW);
				req = NULL;
			}
		}
	}

	if (unlikely (!req))
		return;

	/* manual DMA queue advance after short OUT */
	if (likely (ep->dma != 0)) {
		if (t & (1 << SHORT_PACKET_TRANSFERRED_INTERRUPT)) {
			u32	count;
			int	stopped = ep->stopped;

			/* TRANSFERRED works around OUT_DONE erratum 0112.
			 * we expect (N <= maxpacket) bytes; host wrote M.
			 * iff (M < N) we won't ever see a DMA interrupt.
			 */
			ep->stopped = 1;
			for (count = 0; ; t = readl (&ep->regs->ep_stat)) {

				/* any preceding dma transfers must finish.
				 * dma handles (M >= N), may empty the queue
				 */
				scan_dma_completions (ep);
				if (unlikely (list_empty (&ep->queue)
						|| ep->out_overflow)) {
					req = NULL;
					break;
				}
				req = list_entry (ep->queue.next,
					struct net2280_request, queue);

				/* here either (M < N), a "real" short rx;
				 * or (M == N) and the queue didn't empty
				 */
				if (likely (t & (1 << FIFO_EMPTY))) {
					count = readl (&ep->dma->dmacount);
					count &= DMA_BYTE_COUNT_MASK;
					if (readl (&ep->dma->dmadesc)
							!= req->td_dma)
						req = NULL;
					break;
				}
				udelay(1);
			}

			/* stop DMA, leave ep NAKing */
			writel ((1 << DMA_ABORT), &ep->dma->dmastat);
			spin_stop_dma (ep->dma);

			if (likely (req)) {
				req->td->dmacount = 0;
				t = readl (&ep->regs->ep_avail);
				dma_done (ep, req, count, t);
			}

			/* also flush to prevent erratum 0106 trouble */
			if (unlikely (ep->out_overflow
					|| (ep->dev->chiprev == 0x0100
						&& ep->dev->gadget.speed
							== USB_SPEED_FULL))) {
				out_flush (ep);
				ep->out_overflow = 0;
			}

			/* (re)start dma if needed, stop NAKing */
			ep->stopped = stopped;
			if (!list_empty (&ep->queue))
				restart_dma (ep);
		} else
			DEBUG (ep->dev, "%s dma ep_stat %08x ??\n",
					ep->ep.name, t);
		return;

	/* data packet(s) received (in the fifo, OUT) */
	} else if (t & (1 << DATA_PACKET_RECEIVED_INTERRUPT)) {
		if (read_fifo (ep, req) && ep->num != 0)
			mode = 2;

	/* data packet(s) transmitted (IN) */
	} else if (t & (1 << DATA_PACKET_TRANSMITTED_INTERRUPT)) {
		unsigned	len;

		len = req->req.length - req->req.actual;
		if (len > ep->ep.maxpacket)
			len = ep->ep.maxpacket;
		req->req.actual += len;

		/* if we wrote it all, we're usually done */
		if (req->req.actual == req->req.length) {
			if (ep->num == 0) {
				/* wait for control status */
				if (mode != 2)
					req = NULL;
			} else if (!req->req.zero || len != ep->ep.maxpacket)
				mode = 2;
		}

	/* there was nothing to do ...  */
	} else if (mode == 1)
		return;

	/* done */
	if (mode == 2) {
		/* stream endpoints often resubmit/unlink in completion */
		done (ep, req, 0);

		/* maybe advance queue to next request */
		if (ep->num == 0) {
			/* NOTE:  net2280 could let gadget driver start the
			 * status stage later. since not all controllers let
			 * them control that, the api doesn't (yet) allow it.
			 */
			if (!ep->stopped)
				allow_status (ep);
			req = NULL;
		} else {
			if (!list_empty (&ep->queue) && !ep->stopped)
				req = list_entry (ep->queue.next,
					struct net2280_request, queue);
			else
				req = NULL;
			if (req && !ep->is_in)
				stop_out_naking (ep);
		}
	}

	/* is there a buffer for the next packet?
	 * for best streaming performance, make sure there is one.
	 */
	if (req && !ep->stopped) {

		/* load IN fifo with next packet (may be zlp) */
		if (t & (1 << DATA_PACKET_TRANSMITTED_INTERRUPT))
			write_fifo (ep, &req->req);
	}
}

static struct net2280_ep *
get_ep_by_addr (struct net2280 *dev, u16 wIndex)
{
	struct net2280_ep	*ep;

	if ((wIndex & USB_ENDPOINT_NUMBER_MASK) == 0)
		return &dev->ep [0];
	list_for_each_entry (ep, &dev->gadget.ep_list, ep.ep_list) {
		u8	bEndpointAddress;

		if (!ep->desc)
			continue;
		bEndpointAddress = ep->desc->bEndpointAddress;
		if ((wIndex ^ bEndpointAddress) & USB_DIR_IN)
			continue;
		if ((wIndex & 0x0f) == (bEndpointAddress & 0x0f))
			return ep;
	}
	return NULL;
}

static void handle_stat0_irqs (struct net2280 *dev, u32 stat)
{
	struct net2280_ep	*ep;
	u32			num, scratch;

	/* most of these don't need individual acks */
	stat &= ~(1 << INTA_ASSERTED);
	if (!stat)
		return;
	// DEBUG (dev, "irqstat0 %04x\n", stat);

	/* starting a control request? */
	if (unlikely (stat & (1 << SETUP_PACKET_INTERRUPT))) {
		union {
			u32			raw [2];
			struct usb_ctrlrequest	r;
		} u;
		int				tmp = 0;
		struct net2280_request		*req;

		if (dev->gadget.speed == USB_SPEED_UNKNOWN) {
			if (readl (&dev->usb->usbstat) & (1 << HIGH_SPEED))
				dev->gadget.speed = USB_SPEED_HIGH;
			else
				dev->gadget.speed = USB_SPEED_FULL;
			net2280_led_speed (dev, dev->gadget.speed);
			DEBUG (dev, "%s speed\n",
				(dev->gadget.speed == USB_SPEED_HIGH)
					? "high" : "full");
		}

		ep = &dev->ep [0];
		ep->irqs++;

		/* make sure any leftover request state is cleared */
		stat &= ~(1 << ENDPOINT_0_INTERRUPT);
		while (!list_empty (&ep->queue)) {
			req = list_entry (ep->queue.next,
					struct net2280_request, queue);
			done (ep, req, (req->req.actual == req->req.length)