drivers/net/usb/net1080.c

Source file repositories/reference/linux-study-clean/drivers/net/usb/net1080.c

File Facts

System
Linux kernel
Corpus path
drivers/net/usb/net1080.c
Extension
.c
Size
13737 bytes
Lines
523
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct nc_header {		// packed:
	__le16	hdr_len;		// sizeof nc_header (LE, all)
	__le16	packet_len;		// payload size (including ethhdr)
	__le16	packet_id;		// detects dropped packets
#define MIN_HEADER	6

	// all else is optional, and must start with:
	// __le16	vendorId;	// from usb-if
	// __le16	productId;
} __packed;

#define	PAD_BYTE	((unsigned char)0xAC)

struct nc_trailer {
	__le16	packet_id;
} __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)

/* packets _could_ be up to 64KB... */
#define NC_MAX_PACKET	32767


/*
 * 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 = usbnet_read_cmd(dev, req,
				     USB_DIR_IN | USB_TYPE_VENDOR |
				     USB_RECIP_DEVICE,
				     0, regnum, retval_ptr,
				     sizeof *retval_ptr);
	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);
}

static void
nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value)
{
	usbnet_write_cmd(dev, req,
			 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
			 value, regnum, NULL, 0);
}

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)
{

Annotation

Implementation Notes