usbnet.c

ep9315平台下USB驱动的源码

{
	int status = urb->status;
	
	switch (status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		/* this urb is terminated, clean up */
		dbg("%s - urb shutting down with status: %d",
				__FUNCTION__, status);
		return;
	default:
		dbg("%s - nonzero urb status received: %d",
				__FUNCTION__, urb->status);
	}

	// NOTE:  2.4 still has automagic resubmit, so this would be
	// wrong ... but this code has never worked, is always disabled.
	status = usb_submit_urb (urb, GFP_ATOMIC);
	if (status)
		err ("%s - usb_submit_urb failed with result %d",
		     __FUNCTION__, status);
}

static int gl_interrupt_read (struct usbnet *dev)
{
	struct gl_priv	*priv = dev->priv_data;
	int		retval;

	// issue usb interrupt read
	if (priv && priv->irq_urb) {
		// submit urb
		if ((retval = SUBMIT_URB (priv->irq_urb, GFP_KERNEL)) != 0)
			dbg ("gl_interrupt_read: submit fail - %X...", retval);
		else
			dbg ("gl_interrupt_read: submit success...");
	}

	return 0;
}

// check whether another side is connected
static int genelink_check_connect (struct usbnet *dev)
{
	int			retval;

	dbg ("genelink_check_connect...");

	// detect whether another side is connected
	if ((retval = gl_control_write (dev, GENELINK_CONNECT_WRITE, 0)) != 0) {
		dbg ("%s: genelink_check_connect write fail - %X",
			dev->net.name, retval);
		return retval;
	}

	// usb interrupt read to ack another side 
	if ((retval = gl_interrupt_read (dev)) != 0) {
		dbg ("%s: genelink_check_connect read fail - %X",
			dev->net.name, retval);
		return retval;
	}

	dbg ("%s: genelink_check_connect read success", dev->net.name);
	return 0;
}

// allocate and initialize the private data for genelink
static int genelink_init (struct usbnet *dev)
{
	struct gl_priv *priv;

	// allocate the private data structure
	if ((priv = kmalloc (sizeof *priv, GFP_KERNEL)) == 0) {
		dbg ("%s: cannot allocate private data per device",
			dev->net.name);
		return -ENOMEM;
	}

	// allocate irq urb
	if ((priv->irq_urb = ALLOC_URB (0, GFP_KERNEL)) == 0) {
		dbg ("%s: cannot allocate private irq urb per device",
			dev->net.name);
		kfree (priv);
		return -ENOMEM;
	}

	// fill irq urb
	usb_fill_int_urb (priv->irq_urb, dev->udev,
		usb_rcvintpipe (dev->udev, GENELINK_INTERRUPT_PIPE),
		priv->irq_buf, INTERRUPT_BUFSIZE,
		gl_interrupt_complete, 0,
		GENELINK_INTERRUPT_INTERVAL);

	// set private data pointer
	dev->priv_data = priv;

	return 0;
}

// release the private data
static int genelink_free (struct usbnet *dev)
{
	struct gl_priv	*priv = dev->priv_data;

	if (!priv) 
		return 0;

// FIXME:  can't cancel here; it's synchronous, and
// should have happened earlier in any case (interrupt
// handling needs to be generic)

	// cancel irq urb first
	usb_unlink_urb (priv->irq_urb);

	// free irq urb
	usb_free_urb (priv->irq_urb);

	// free the private data structure
	kfree (priv);

	return 0;
}

#endif

static int genelink_rx_fixup (struct usbnet *dev, struct sk_buff *skb)
{
	struct gl_header	*header;
	struct gl_packet	*packet;
	struct sk_buff		*gl_skb;
	int			status;
	u32			size;

	header = (struct gl_header *) skb->data;

	// get the packet count of the received skb
	le32_to_cpus (&header->packet_count);
	if ((header->packet_count > GL_MAX_TRANSMIT_PACKETS)
			|| (header->packet_count < 0)) {
		dbg ("genelink: illegal received packet count %d",
			header->packet_count);
		return 0;
	}

	// set the current packet pointer to the first packet
	packet = &header->packets;

	// decrement the length for the packet count size 4 bytes
	skb_pull (skb, 4);

	while (header->packet_count > 1) {
		// get the packet length
		size = packet->packet_length;

		// this may be a broken packet
		if (size > GL_MAX_PACKET_LEN) {
			dbg ("genelink: illegal rx length %d", size);
			return 0;
		}

		// allocate the skb for the individual packet
		gl_skb = alloc_skb (size, GFP_ATOMIC);
		if (gl_skb) {

			// copy the packet data to the new skb
			memcpy (gl_skb->data, packet->packet_data, size);

			// set skb data size
			gl_skb->len = size;
			gl_skb->dev = &dev->net;

			// determine the packet's protocol ID
			gl_skb->protocol = eth_type_trans (gl_skb, &dev->net);

			// update the status
			dev->stats.rx_packets++;
			dev->stats.rx_bytes += size;

			// notify os of the received packet
			status = netif_rx (gl_skb);
		}

		// advance to the next packet
		packet = (struct gl_packet *)
			&packet->packet_data [size];
		header->packet_count--;

		// shift the data pointer to the next gl_packet
		skb_pull (skb, size + 4);
	}

	// skip the packet length field 4 bytes
	skb_pull (skb, 4);

	if (skb->len > GL_MAX_PACKET_LEN) {
		dbg ("genelink: illegal rx length %d", skb->len);
		return 0;
	}
	return 1;
}

static struct sk_buff *
genelink_tx_fixup (struct usbnet *dev, struct sk_buff *skb, int flags)
{
	int 	padlen;
	int	length = skb->len;
	int	headroom = skb_headroom (skb);
	int	tailroom = skb_tailroom (skb);
	u32	*packet_count;
	u32	*packet_len;

	// FIXME:  magic numbers, bleech
	padlen = ((skb->len + (4 + 4*1)) % 64) ? 0 : 1;

	if ((!skb_cloned (skb))
			&& ((headroom + tailroom) >= (padlen + (4 + 4*1)))) {
		if ((headroom < (4 + 4*1)) || (tailroom < padlen)) {
			skb->data = memmove (skb->head + (4 + 4*1),
					     skb->data, skb->len);
			skb->tail = skb->data + skb->len;
		}
	} else {
		struct sk_buff	*skb2;
		skb2 = skb_copy_expand (skb, (4 + 4*1) , padlen, flags);
		dev_kfree_skb_any (skb);
		skb = skb2;
	}

	// attach the packet count to the header
	packet_count = (u32 *) skb_push (skb, (4 + 4*1));
	packet_len = packet_count + 1;

	// FIXME little endian?
	*packet_count = 1;
	*packet_len = length;

	// add padding byte
	if ((skb->len % EP_SIZE (dev)) == 0)
		skb_put (skb, 1);

	return skb;
}

static const struct driver_info	genelink_info = {
	.description =	"Genesys GeneLink",
	.flags =	FLAG_FRAMING_GL | FLAG_NO_SETINT,
	.rx_fixup =	genelink_rx_fixup,
	.tx_fixup =	genelink_tx_fixup,

	.in = 1, .out = 2,
	.epsize =64,

#ifdef	GENELINK_ACK
	.check_connect =genelink_check_connect,
#endif
};

#endif /* CONFIG_USB_GENESYS */



#ifdef	CONFIG_USB_NET1080

/*-------------------------------------------------------------------------
 *
 * Netchip 1080 driver ... http://www.netchip.com
 * Used in LapLink cables
 *
 *-------------------------------------------------------------------------*/

/*
 * NetChip framing of ethernet packets, supporting additional error
 * checks for links that may drop bulk packets from inside messages.
 * Odd USB length == always short read for last usb packet.
 *	- nc_header
 *	- Ethernet header (14 bytes)
 *	- payload
 *	- (optional padding byte, if needed so length becomes odd)
 *	- nc_trailer
 *
 * This framing is to be avoided for non-NetChip devices.
 */

struct nc_header {		// packed:
	u16	hdr_len;		// sizeof nc_header (LE, all)
	u16	packet_len;		// payload size (including ethhdr)
	u16	packet_id;		// detects dropped packets
#define MIN_HEADER	6

	// all else is optional, and must start with:
	// u16	vendorId;		// from usb-if
	// u16	productId;
} __attribute__((__packed__));

#define	PAD_BYTE	((unsigned char)0xAC)

struct nc_trailer {
	u16	packet_id;
} __attribute__((__packed__));

// packets may use FLAG_FRAMING_NC and optional pad
#define FRAMED_SIZE(mtu) (sizeof (struct nc_header) \
				+ sizeof (struct ethhdr) \
				+ (mtu) \
				+ 1 \
				+ sizeof (struct nc_trailer))

#define MIN_FRAMED	FRAMED_SIZE(0)


/*
 * Zero means no timeout; else, how long a 64 byte bulk packet may be queued
 * before the hardware drops it.  If that's done, the driver will need to
 * frame network packets to guard against the dropped USB packets.  The win32
 * driver sets this for both sides of the link.
 */
#define	NC_READ_TTL_MS	((u8)255)	// ms

/*
 * We ignore most registers and EEPROM contents.
 */
#define	REG_USBCTL	((u8)0x04)
#define REG_TTL		((u8)0x10)
#define REG_STATUS	((u8)0x11)

/*
 * Vendor specific requests to read/write data
 */
#define	REQUEST_REGISTER	((u8)0x10)
#define	REQUEST_EEPROM		((u8)0x11)

static int
nc_vendor_read (struct usbnet *dev, u8 req, u8 regnum, u16 *retval_ptr)
{
	int status = usb_control_msg (dev->udev,
		usb_rcvctrlpipe (dev->udev, 0),
		req,
		USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
		0, regnum,
		retval_ptr, sizeof *retval_ptr,
		CONTROL_TIMEOUT_JIFFIES);
	if (status > 0)
		status = 0;
	if (!status)
		le16_to_cpus (retval_ptr);
	return status;
}

static inline int
nc_register_read (struct usbnet *dev, u8 regnum, u16 *retval_ptr)
{
	return nc_vendor_read (dev, REQUEST_REGISTER, regnum, retval_ptr);
}

// no retval ... can become async, usable in_interrupt()
static void
nc_vendor_write (struct usbnet *dev, u8 req, u8 regnum, u16 value)
{
	usb_control_msg (dev->udev,
		usb_sndctrlpipe (dev->udev, 0),
		req,
		USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
		value, regnum,
		0, 0,			// data is in setup packet
		CONTROL_TIMEOUT_JIFFIES);
}

static inline void
nc_register_write (struct usbnet *dev, u8 regnum, u16 value)
{
	nc_vendor_write (dev, REQUEST_REGISTER, regnum, value);
}


#if 0
static void nc_dump_registers (struct usbnet *dev)
{
	u8	reg;
	u16	*vp = kmalloc (sizeof (u16));

	if (!vp) {
		dbg ("no memory?");
		return;
	}

	dbg ("%s registers:", dev->net.name);
	for (reg = 0; reg < 0x20; reg++) {
		int retval;

		// reading some registers is trouble
		if (reg >= 0x08 && reg <= 0xf)
			continue;
		if (reg >= 0x12 && reg <= 0x1e)
			continue;

		retval = nc_register_read (dev, reg, vp);
		if (retval < 0)
			dbg ("%s reg [0x%x] ==> error %d",
				dev->net.name, reg, retval);
		else
			dbg ("%s reg [0x%x] = 0x%x",
				dev->net.name, reg, *vp);
	}
	kfree (vp);
}
#endif


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

/*
 * Control register
 */

#define	USBCTL_WRITABLE_MASK	0x1f0f
// bits 15-13 reserved, r/o
#define	USBCTL_ENABLE_LANG	(1 << 12)
#define	USBCTL_ENABLE_MFGR	(1 << 11)
#define	USBCTL_ENABLE_PROD	(1 << 10)
#define	USBCTL_ENABLE_SERIAL	(1 << 9)
#define	USBCTL_ENABLE_DEFAULTS	(1 << 8)
// bits 7-4 reserved, r/o
#define	USBCTL_FLUSH_OTHER	(1 << 3)
#define	USBCTL_FLUSH_THIS	(1 << 2)
#define	USBCTL_DISCONN_OTHER	(1 << 1)
#define	USBCTL_DISCONN_THIS	(1 << 0)

static inline void nc_dump_usbctl (struct usbnet *dev, u16 usbctl)
{
#ifdef DEBUG
	devdbg (dev, "net1080 %s-%s usbctl 0x%x:%s%s%s%s%s;"
			" this%s%s;"
			" other%s%s; r/o 0x%x",
		dev->udev->bus->bus_name, dev->udev->devpath,
		usbctl,
		(usbctl & USBCTL_ENABLE_LANG) ? " lang" : "",
		(usbctl & USBCTL_ENABLE_MFGR) ? " mfgr" : "",
		(usbctl & USBCTL_ENABLE_PROD) ? " prod" : "",
		(usbctl & USBCTL_ENABLE_SERIAL) ? " serial" : "",
		(usbctl & USBCTL_ENABLE_DEFAULTS) ? " defaults" : "",

		(usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "",
		(usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "",
		(usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "",
		(usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "",
		usbctl & ~USBCTL_WRITABLE_MASK
		);
#endif
}

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

/*
 * Status register
 */

#define	STATUS_PORT_A		(1 << 15)

#define	STATUS_CONN_OTHER	(1 << 14)
#define	STATUS_SUSPEND_OTHER	(1 << 13)
#define	STATUS_MAILBOX_OTHER	(1 << 12)
#define	STATUS_PACKETS_OTHER(n)	(((n) >> 8) && 0x03)

#define	STATUS_CONN_THIS	(1 << 6)
#define	STATUS_SUSPEND_THIS	(1 << 5)
#define	STATUS_MAILBOX_THIS	(1 << 4)
#define	STATUS_PACKETS_THIS(n)	(((n) >> 0) && 0x03)