path: root/drivers/net/usb/sr9800.c

/* CoreChip-sz SR9800 one chip USB 2.0 Ethernet Devices
 *
 * Author : Liu Junliang <liujunliang_ljl@163.com>
 *
 * Based on asix_common.c, asix_devices.c
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2.  This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.*
 */

#include <linux/module.h>
#include <linux/kmod.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/crc32.h>
#include <linux/usb/usbnet.h>
#include <linux/slab.h>
#include <linux/if_vlan.h>

#include "sr9800.h"

static int sr_read_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index,
			    u16 size, void *data)
{
	int err;

	err = usbnet_read_cmd(dev, cmd, SR_REQ_RD_REG, value, index,
			      data, size);
	if ((err != size) && (err >= 0))
		err = -EINVAL;

	return err;
}

static int sr_write_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index,
			     u16 size, void *data)
{
	int err;

	err = usbnet_write_cmd(dev, cmd, SR_REQ_WR_REG, value, index,
			      data, size);
	if ((err != size) && (err >= 0))
		err = -EINVAL;

	return err;
}

static void
sr_write_cmd_async(struct usbnet *dev, u8 cmd, u16 value, u16 index,
		   u16 size, void *data)
{
	usbnet_write_cmd_async(dev, cmd, SR_REQ_WR_REG, value, index, data,
			       size);
}

static int sr_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
{
	int offset = 0;

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

	while (offset + sizeof(u32) < skb->len) {
		struct sk_buff *sr_skb;
		u16 size;
		u32 header = get_unaligned_le32(skb->data + offset);

		offset += sizeof(u32);
		/* get the packet length */
		size = (u16) (header & 0x7ff);
		if (size != ((~header >> 16) & 0x07ff)) {
			netdev_err(dev->net, "%s : Bad Header Length\n",
				   __func__);
			return 0;
		}

		if ((size > dev->net->mtu + ETH_HLEN + VLAN_HLEN) ||
		    (size + offset > skb->len)) {
			netdev_err(dev->net, "%s : Bad RX Length %d\n",
				   __func__, size);
			return 0;
		}
		sr_skb = netdev_alloc_skb_ip_align(dev->net, size);
		if (!sr_skb)
			return 0;

		skb_put(sr_skb, size);
		memcpy(sr_skb->data, skb->data + offset, size);
		usbnet_skb_return(dev, sr_skb);

		offset += (size + 1) & 0xfffe;
	}

	if (skb->len != offset) {
		netdev_err(dev->net, "%s : Bad SKB Length %d\n", __func__,
			   skb->len);
		return 0;
	}

	return 1;
}

static struct sk_buff *sr_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
					gfp_t flags)
{
	int headroom = skb_headroom(skb);
	int tailroom = skb_tailroom(skb);
	u32 padbytes = 0xffff0000;
	u32 packet_len;
	int padlen;

	padlen = ((skb->len + 4) % (dev->maxpacket - 1)) ? 0 : 4;

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

	skb_push(skb, 4);
	packet_len = (((skb->len - 4) ^ 0x0000ffff) << 16) + (skb->len - 4);
	cpu_to_le32s(&packet_len);
	skb_copy_to_linear_data(skb, &packet_len, sizeof(packet_len));

	if (padlen) {
		cpu_to_le32s(&padbytes);
		memcpy(