[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / net / usb / gl620a.c

/*
 * GeneSys GL620USB-A based links
 * Copyright (C) 2001 by Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
 * Copyright (C) 2001 by Stanislav Brabec <utx@penguin.cz>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

// #define	DEBUG			// error path messages, extra info
// #define	VERBOSE			// more; success messages

#include <linux/module.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/workqueue.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/usb/usbnet.h>
#include <linux/gfp.h>


/*
 * GeneSys GL620USB-A (www.genesyslogic.com.tw)
 *
 * ... should partially interop with the Win32 driver for this hardware.
 * The GeneSys docs imply there's some NDIS issue motivating this framing.
 *
 * Some info from GeneSys:
 *  - GL620USB-A is full duplex; GL620USB is only half duplex for bulk.
 *    (Some cables, like the BAFO-100c, use the half duplex version.)
 *  - For the full duplex model, the low bit of the version code says
 *    which side is which ("left/right").
 *  - For the half duplex type, a control/interrupt handshake settles
 *    the transfer direction.  (That's disabled here, partially coded.)
 *    A control URB would block until other side writes an interrupt.
 *
 * Original code from Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
 * and merged into "usbnet" by Stanislav Brabec <utx@penguin.cz>.
 */

// control msg write command
#define GENELINK_CONNECT_WRITE			0xF0
// interrupt pipe index
#define GENELINK_INTERRUPT_PIPE			0x03
// interrupt read buffer size
#define INTERRUPT_BUFSIZE			0x08
// interrupt pipe interval value
#define GENELINK_INTERRUPT_INTERVAL		0x10
// max transmit packet number per transmit
#define GL_MAX_TRANSMIT_PACKETS			32
// max packet length
#define GL_MAX_PACKET_LEN			1514
// max receive buffer size
#define GL_RCV_BUF_SIZE		\
	(((GL_MAX_PACKET_LEN + 4) * GL_MAX_TRANSMIT_PACKETS) + 4)

struct gl_packet {
	__le32		packet_length;
	char		packet_data [1];
};

struct gl_header {
	__le32			packet_count;
	struct gl_packet	packets;
};

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;
	u32			size;
	u32			count;

	/* This check is no longer done by usbnet */
	if (skb->len < dev->net->hard_header_len)
		return 0;

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

	// get the packet count of the received skb
	count = le32_to_cpu(header->packet_count);
	if (count > GL_MAX_TRANSMIT_PACKETS) {
		netdev_dbg(dev->net,
			   "genelink: invalid received packet count %u\n",
			   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 (count > 1) {
		// get the packet length
		size = le32_to_cpu(packet->packet_length);

		// this may be a broken packet
		if (size > GL_MAX_PACKET_LEN) {
			netdev_dbg(dev->net, "genelink: invalid rx length %d\n",
				   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(skb_put(gl_skb, size),
					packet->packet_data, size);
			usbnet_skb_return(dev, gl_skb);
		}

		// advance to the next packet
		packet = (struct gl_packet *)&packet->packet_data[size];
		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) {
		netdev_dbg(dev->net, "genelink: invalid rx length %d\n",
			   skb->len);
		return 0;
	}
	return 1;
}

static struct sk_buff *
genelink_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
{
	int 	padlen;
	int	length = skb->len;
	int	headroom = skb_headroom(skb);
	int	tailroom = skb_tailroom(skb);
	__le32	*packet_count;
	__le32	*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_set_tail_pointer(skb, skb->len);
		}
	} else {
		struct sk_buff	*skb2;
		skb2 = skb_copy_expand(skb, (4 + 4*1) , padlen, flags);
		dev_kfree_skb_any(skb);
		skb = skb2;
		if (!skb)
			return NULL;
	}

	// attach the packet count to the header
	packet_count = (__le32 *) skb_push(skb, (4 + 4*1));
	packet_len = packet_count + 1;

	*packet_count = cpu_to_le32(1);
	*packet_len = cpu_to_le32(length);

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

	return skb;
}

static int genelink_bind(struct usbnet *dev, struct usb_interface *intf)
{
	dev->hard_mtu = GL_RCV_BUF_SIZE;
	dev->net->hard_header_len += 4;
	dev->in = usb_rcvbulkpipe(dev->udev, dev->driver_info->in);
	dev->out = usb_sndbulkpipe(dev->udev, dev->driver_info->out);
	return 0;
}

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

	.in = 1, .out = 2,

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

static const struct usb_device_id	products [] = {

{
	USB_DEVICE(0x05e3, 0x0502),	// GL620USB-A
	.driver_info =	(unsigned long) &genelink_info,
},
	/* NOT: USB_DEVICE(0x05e3, 0x0501),	// GL620USB
	 * that's half duplex, not currently supported
	 */
	{ },		// END
};
MODULE_DEVICE_TABLE(usb, products);

static struct usb_driver gl620a_driver = {
	.name =		"gl620a",
	.id_table =	products,
	.probe =	usbnet_probe,
	.disconnect =	usbnet_disconnect,
	.suspend =	usbnet_suspend,
	.resume =	usbnet_resume,
	.disable_hub_initiated_lpm = 1,
};

module_usb_driver(gl620a_driver);

MODULE_AUTHOR("Jiun-Jie Huang");
MODULE_DESCRIPTION("GL620-USB-A Host-to-Host Link cables");
MODULE_LICENSE("GPL");
Commit	Line	Data
47ee3051 DB	1	/*
	2	* GeneSys GL620USB-A based links
	3	* Copyright (C) 2001 by Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
	4	* Copyright (C) 2001 by Stanislav Brabec <utx@penguin.cz>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
	20
	21	// #define DEBUG // error path messages, extra info
	22	// #define VERBOSE // more; success messages
	23
47ee3051	24	#include <linux/module.h>
47ee3051 DB	25	#include <linux/init.h>
	26	#include <linux/netdevice.h>
	27	#include <linux/etherdevice.h>
	28	#include <linux/ethtool.h>
	29	#include <linux/workqueue.h>
	30	#include <linux/mii.h>
	31	#include <linux/usb.h>
3692e94f	32	#include <linux/usb/usbnet.h>
5a0e3ad6	33	#include <linux/gfp.h>
47ee3051 DB	34
	35
	36	/*
	37	* GeneSys GL620USB-A (www.genesyslogic.com.tw)
	38	*
	39	* ... should partially interop with the Win32 driver for this hardware.
	40	* The GeneSys docs imply there's some NDIS issue motivating this framing.
	41	*
	42	* Some info from GeneSys:
	43	* - GL620USB-A is full duplex; GL620USB is only half duplex for bulk.
	44	* (Some cables, like the BAFO-100c, use the half duplex version.)
	45	* - For the full duplex model, the low bit of the version code says
	46	* which side is which ("left/right").
	47	* - For the half duplex type, a control/interrupt handshake settles
	48	* the transfer direction. (That's disabled here, partially coded.)
	49	* A control URB would block until other side writes an interrupt.
	50	*
	51	* Original code from Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
	52	* and merged into "usbnet" by Stanislav Brabec <utx@penguin.cz>.
	53	*/
	54
	55	// control msg write command
	56	#define GENELINK_CONNECT_WRITE 0xF0
	57	// interrupt pipe index
	58	#define GENELINK_INTERRUPT_PIPE 0x03
	59	// interrupt read buffer size
	60	#define INTERRUPT_BUFSIZE 0x08
	61	// interrupt pipe interval value
	62	#define GENELINK_INTERRUPT_INTERVAL 0x10
	63	// max transmit packet number per transmit
	64	#define GL_MAX_TRANSMIT_PACKETS 32
	65	// max packet length
	66	#define GL_MAX_PACKET_LEN 1514
	67	// max receive buffer size
	68	#define GL_RCV_BUF_SIZE \
	69	(((GL_MAX_PACKET_LEN + 4) * GL_MAX_TRANSMIT_PACKETS) + 4)
	70
	71	struct gl_packet {
53ebb3b8	72	__le32 packet_length;
47ee3051 DB	73	char packet_data [1];
	74	};
	75
	76	struct gl_header {
53ebb3b8	77	__le32 packet_count;
47ee3051 DB	78	struct gl_packet packets;
	79	};
	80
47ee3051 DB	81	static int genelink_rx_fixup(struct usbnet dev, struct sk_buff skb)
	82	{
	83	struct gl_header *header;
	84	struct gl_packet *packet;
	85	struct sk_buff *gl_skb;
	86	u32 size;
53ebb3b8	87	u32 count;
47ee3051	88
07ea875e EG	89	/* This check is no longer done by usbnet */
	90	if (skb->len < dev->net->hard_header_len)
	91	return 0;
	92
47ee3051 DB	93	header = (struct gl_header *) skb->data;
	94
	95	// get the packet count of the received skb
53ebb3b8 AV	96	count = le32_to_cpu(header->packet_count);
53ebb3b8 AV	97	if (count > GL_MAX_TRANSMIT_PACKETS) {
49ae25b0 GKH	98	netdev_dbg(dev->net,
	99	"genelink: invalid received packet count %u\n",
	100	count);
47ee3051 DB	101	return 0;
	102	}
	103
	104	// set the current packet pointer to the first packet
	105	packet = &header->packets;
	106
	107	// decrement the length for the packet count size 4 bytes
	108	skb_pull(skb, 4);
	109
53ebb3b8	110	while (count > 1) {
47ee3051 DB	111	// get the packet length
	112	size = le32_to_cpu(packet->packet_length);
	113
	114	// this may be a broken packet
	115	if (size > GL_MAX_PACKET_LEN) {
49ae25b0 GKH	116	netdev_dbg(dev->net, "genelink: invalid rx length %d\n",
49ae25b0 GKH	117	size);
47ee3051 DB	118	return 0;
	119	}
	120
	121	// allocate the skb for the individual packet
	122	gl_skb = alloc_skb(size, GFP_ATOMIC);
	123	if (gl_skb) {
	124
	125	// copy the packet data to the new skb
	126	memcpy(skb_put(gl_skb, size),
	127	packet->packet_data, size);
	128	usbnet_skb_return(dev, gl_skb);
	129	}
	130
	131	// advance to the next packet
53ebb3b8 AV	132	packet = (struct gl_packet *)&packet->packet_data[size];
53ebb3b8 AV	133	count--;
47ee3051 DB	134
	135	// shift the data pointer to the next gl_packet
	136	skb_pull(skb, size + 4);
	137	}
	138
	139	// skip the packet length field 4 bytes
	140	skb_pull(skb, 4);
	141
	142	if (skb->len > GL_MAX_PACKET_LEN) {
49ae25b0 GKH	143	netdev_dbg(dev->net, "genelink: invalid rx length %d\n",
49ae25b0 GKH	144	skb->len);
47ee3051 DB	145	return 0;
	146	}
	147	return 1;
	148	}
	149
	150	static struct sk_buff *
55016f10	151	genelink_tx_fixup(struct usbnet dev, struct sk_buff skb, gfp_t flags)
47ee3051 DB	152	{
	153	int padlen;
	154	int length = skb->len;
	155	int headroom = skb_headroom(skb);
	156	int tailroom = skb_tailroom(skb);
53ebb3b8 AV	157	__le32 *packet_count;
53ebb3b8 AV	158	__le32 *packet_len;
47ee3051 DB	159
	160	// FIXME: magic numbers, bleech
	161	padlen = ((skb->len + (4 + 4*1)) % 64) ? 0 : 1;
	162
	163	if ((!skb_cloned(skb))
	164	&& ((headroom + tailroom) >= (padlen + (4 + 4*1)))) {
	165	if ((headroom < (4 + 4*1)) \|\| (tailroom < padlen)) {
	166	skb->data = memmove(skb->head + (4 + 4*1),
	167	skb->data, skb->len);
27a884dc	168	skb_set_tail_pointer(skb, skb->len);
47ee3051 DB	169	}
	170	} else {
	171	struct sk_buff *skb2;
	172	skb2 = skb_copy_expand(skb, (4 + 4*1) , padlen, flags);
	173	dev_kfree_skb_any(skb);
	174	skb = skb2;
	175	if (!skb)
	176	return NULL;
	177	}
	178
	179	// attach the packet count to the header
53ebb3b8	180	packet_count = (__le32 ) skb_push(skb, (4 + 41));
47ee3051 DB	181	packet_len = packet_count + 1;
	182
	183	*packet_count = cpu_to_le32(1);
	184	*packet_len = cpu_to_le32(length);
	185
	186	// add padding byte
	187	if ((skb->len % dev->maxpacket) == 0)
	188	skb_put(skb, 1);
	189
	190	return skb;
	191	}
	192
	193	static int genelink_bind(struct usbnet dev, struct usb_interface intf)
	194	{
	195	dev->hard_mtu = GL_RCV_BUF_SIZE;
	196	dev->net->hard_header_len += 4;
	197	dev->in = usb_rcvbulkpipe(dev->udev, dev->driver_info->in);
	198	dev->out = usb_sndbulkpipe(dev->udev, dev->driver_info->out);
	199	return 0;
	200	}
	201
	202	static const struct driver_info genelink_info = {
	203	.description = "Genesys GeneLink",
c261344d	204	.flags = FLAG_POINTTOPOINT \| FLAG_FRAMING_GL \| FLAG_NO_SETINT,
47ee3051 DB	205	.bind = genelink_bind,
	206	.rx_fixup = genelink_rx_fixup,
	207	.tx_fixup = genelink_tx_fixup,
	208
	209	.in = 1, .out = 2,
	210
	211	#ifdef GENELINK_ACK
	212	.check_connect =genelink_check_connect,
	213	#endif
	214	};
	215
	216	static const struct usb_device_id products [] = {
	217
	218	{
	219	USB_DEVICE(0x05e3, 0x0502), // GL620USB-A
	220	.driver_info = (unsigned long) &genelink_info,
	221	},
	222	/* NOT: USB_DEVICE(0x05e3, 0x0501), // GL620USB
	223	* that's half duplex, not currently supported
	224	*/
	225	{ }, // END
	226	};
	227	MODULE_DEVICE_TABLE(usb, products);
	228
	229	static struct usb_driver gl620a_driver = {
47ee3051 DB	230	.name = "gl620a",
	231	.id_table = products,
	232	.probe = usbnet_probe,
	233	.disconnect = usbnet_disconnect,
	234	.suspend = usbnet_suspend,
	235	.resume = usbnet_resume,
e1f12eb6	236	.disable_hub_initiated_lpm = 1,
47ee3051 DB	237	};
47ee3051 DB	238
d632eb1b	239	module_usb_driver(gl620a_driver);
47ee3051 DB	240
	241	MODULE_AUTHOR("Jiun-Jie Huang");
	242	MODULE_DESCRIPTION("GL620-USB-A Host-to-Host Link cables");
	243	MODULE_LICENSE("GPL");
	244