/*
 * Copyright (c) 2011 The Chromium OS Authors.
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * 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
 */

#include <common.h>
#include <usb.h>
#include <linux/mii.h>
#include "usb_ether.h"


/* ASIX AX8817X based USB 2.0 Ethernet Devices */

#define AX_CMD_SET_SW_MII		0x06
#define AX_CMD_READ_MII_REG		0x07
#define AX_CMD_WRITE_MII_REG		0x08
#define AX_CMD_SET_HW_MII		0x0a
#define AX_CMD_READ_RX_CTL		0x0f
#define AX_CMD_WRITE_RX_CTL		0x10
#define AX_CMD_WRITE_IPG0		0x12
#define AX_CMD_READ_NODE_ID		0x13
#define AX_CMD_READ_PHY_ID		0x19
#define AX_CMD_WRITE_MEDIUM_MODE	0x1b
#define AX_CMD_WRITE_GPIOS		0x1f
#define AX_CMD_SW_RESET			0x20
#define AX_CMD_SW_PHY_SELECT		0x22

#define AX_SWRESET_CLEAR		0x00
#define AX_SWRESET_PRTE			0x04
#define AX_SWRESET_PRL			0x08
#define AX_SWRESET_IPRL			0x20
#define AX_SWRESET_IPPD			0x40

#define AX88772_IPG0_DEFAULT		0x15
#define AX88772_IPG1_DEFAULT		0x0c
#define AX88772_IPG2_DEFAULT		0x12

/* AX88772 & AX88178 Medium Mode Register */
#define AX_MEDIUM_PF		0x0080
#define AX_MEDIUM_JFE		0x0040
#define AX_MEDIUM_TFC		0x0020
#define AX_MEDIUM_RFC		0x0010
#define AX_MEDIUM_ENCK		0x0008
#define AX_MEDIUM_AC		0x0004
#define AX_MEDIUM_FD		0x0002
#define AX_MEDIUM_GM		0x0001
#define AX_MEDIUM_SM		0x1000
#define AX_MEDIUM_SBP		0x0800
#define AX_MEDIUM_PS		0x0200
#define AX_MEDIUM_RE		0x0100

#define AX88178_MEDIUM_DEFAULT	\
	(AX_MEDIUM_PS | AX_MEDIUM_FD | AX_MEDIUM_AC | \
	 AX_MEDIUM_RFC | AX_MEDIUM_TFC | AX_MEDIUM_JFE | \
	 AX_MEDIUM_RE)

#define AX88772_MEDIUM_DEFAULT	\
	(AX_MEDIUM_FD | AX_MEDIUM_RFC | \
	 AX_MEDIUM_TFC | AX_MEDIUM_PS | \
	 AX_MEDIUM_AC | AX_MEDIUM_RE)

/* AX88772 & AX88178 RX_CTL values */
#define AX_RX_CTL_SO			0x0080
#define AX_RX_CTL_AB			0x0008

#define AX_DEFAULT_RX_CTL	\
	(AX_RX_CTL_SO | AX_RX_CTL_AB)

/* GPIO 2 toggles */
#define AX_GPIO_GPO2EN		0x10	/* GPIO2 Output enable */
#define AX_GPIO_GPO_2		0x20	/* GPIO2 Output value */
#define AX_GPIO_RSE		0x80	/* Reload serial EEPROM */

/* local defines */
#define ASIX_BASE_NAME "asx"
#define USB_CTRL_SET_TIMEOUT 5000
#define USB_CTRL_GET_TIMEOUT 5000
#define USB_BULK_SEND_TIMEOUT 5000
#define USB_BULK_RECV_TIMEOUT 5000

#define AX_RX_URB_SIZE 2048
#define PHY_CONNECT_TIMEOUT 5000

/* local vars */
static int curr_eth_dev; /* index for name of next device detected */

/*
 * Asix infrastructure commands
 */
static int asix_write_cmd(struct ueth_data *dev, u8 cmd, u16 value, u16 index,
			     u16 size, void *data)
{
	int len;

	debug("asix_write_cmd() cmd=0x%02x value=0x%04x index=0x%04x "
		"size=%d\n", cmd, value, index, size);

	len = usb_control_msg(
		dev->pusb_dev,
		usb_sndctrlpipe(dev->pusb_dev, 0),
		cmd,
		USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
		value,
		index,
		data,
		size,
		USB_CTRL_SET_TIMEOUT);

	return len == size ? 0 : -1;
}

static int asix_read_cmd(struct ueth_data *dev, u8 cmd, u16 value, u16 index,
			    u16 size, void *data)
{
	int len;

	debug("asix_read_cmd() cmd=0x%02x value=0x%04x index=0x%04x size=%d\n",
		cmd, value, index, size);

	len = usb_control_msg(
		dev->pusb_dev,
		usb_rcvctrlpipe(dev->pusb_dev, 0),
		cmd,
		USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
		value,
		index,
		data,
		size,
		USB_CTRL_GET_TIMEOUT);
	return len == size ? 0 : -1;
}

static inline int asix_set_sw_mii(struct ueth_data *dev)
{
	int ret;

	ret = asix_write_cmd(dev, AX_CMD_SET_SW_MII, 0x0000, 0, 0, NULL);
	if (ret < 0)
		debug("Failed to enable software MII access\n");
	return ret;
}

static inline int asix_set_hw_mii(struct ueth_data *dev)
{
	int ret;

	ret = asix_write_cmd(dev, AX_CMD_SET_HW_MII, 0x0000, 0, 0, NULL);
	if (ret < 0)
		debug("Failed to enable hardware MII access\n");
	return ret;
}

static int asix_mdio_read(struct ueth_data *dev, int phy_id, int loc)
{
	__le16 res;

	asix_set_sw_mii(dev);
	asix_read_cmd(dev, AX_CMD_READ_MII_REG, phy_id, (__u16)loc, 2, &res);
	asix_set_hw_mii(dev);

	debug("asix_mdio_read() phy_id=0x%02x, loc=0x%02x, returns=0x%04x\n",
			phy_id, loc, le16_to_cpu(res));

	return le16_to_cpu(res);
}

static void
asix_mdio_write(struct ueth_data *dev, int phy_id, int loc, int val)
{
	__le16 res = cpu_to_le16(val);

	debug("asix_mdio_write() phy_id=0x%02x, loc=0x%02x, val=0x%04x\n",
			phy_id, loc, val);
	asix_set_sw_mii(dev);
	asix_write_cmd(dev, AX_CMD_WRITE_MII_REG, phy_id, (__u16)loc, 2, &res);
	asix_set_hw_mii(dev);
}

/*
 * Asix "high level" commands
 */
static int asix_sw_reset(struct ueth_data *dev, u8 flags)
{
	int ret;

	ret = asix_write_cmd(dev, AX_CMD_SW_RESET, flags, 0, 0, NULL);
	if (ret < 0)
		debug("Failed to send software reset: %02x\n", ret);
	else
		udelay(150 * 1000);

	return ret;
}

static inline int asix_get_phy_addr(struct ueth_data *dev)
{
	u8 buf[2];
	int ret = asix_read_cmd(dev, AX_CMD_READ_PHY_ID, 0, 0, 2, buf);

	debug("asix_get_phy_addr()\n");

	if (ret < 0) {
		debug("Error reading PHYID register: %02x\n", ret);
		goto out;
	}
	debug("asix_get_phy_addr() returning 0x%04x\n", *((__le16 *)buf));
	ret = buf[1];

out:
	return ret;
}

static int asix_write_medium_mode(struct ueth_data *dev, u16 mode)
{
	int ret;

	debug("asix_write_medium_mode() - mode = 0x%04x\n", mode);
	ret = asix_write_cmd(dev, AX_CMD_WRITE_MEDIUM_MODE, mode,
			0, 0, NULL);
	if (ret < 0) {
		debug("Failed to write Medium Mode mode to 0x%04x: %02x\n",
			mode, ret);
	}
	return ret;
}

static u16 asix_read_rx_ctl(struct ueth_data *dev)
{
	__le16 v;
	int ret = asix_read_cmd(dev, AX_CMD_READ_RX_CTL, 0, 0, 2, &v);

	if (ret < 0)
		debug("Error reading RX_CTL register: %02x\n", ret);
	else
		ret = le16_to_cpu(v);
	return ret;
}

static int asix_write_rx_ctl(struct ueth_data *dev, u16 mode)
{
	int ret;

	debug("asix_write_rx_ctl() - mode = 0x%04x\n", mode);
	ret = asix_write_cmd(dev, AX_CMD_WRITE_RX_CTL, mode, 0, 0, NULL);
	if (ret < 0) {
		debug("Failed to write RX_CTL mode to 0x%04x: %02x\n",
				mode, ret);
	}
	return ret;
}

static int asix_write_gpio(struct ueth_data *dev, u16 value, int sleep)
{
	int ret;

	debug("asix_write_gpio() - value = 0x%04x\n", value);
	ret = asix_write_cmd(dev, AX_CMD_WRITE_GPIOS, value, 0, 0, NULL);
	if (ret < 0) {
		debug("Failed to write GPIO value 0x%04x: %02x\n",
			value, ret);
	}
	if (sleep)
		udelay(sleep * 1000);

	return ret;
}

/*
 * mii commands
 */

/*
 * mii_nway_restart - restart NWay (autonegotiation) for this interface
 *
 * Returns 0 on success, negative on error.
 */
static int mii_nway_restart(struct ueth_data *dev)
{
	int bmcr;
	int r = -1;

	/* if autoneg is off, it's an error */
	bmcr = asix_mdio_read(dev, dev->phy_id, MII_BMCR);

	if (bmcr & BMCR_ANENABLE) {
		bmcr |= BMCR_ANRESTART;
		asix_mdio_write(dev, dev->phy_id, MII_BMCR, bmcr);
		r = 0;
	}

	return r;
}

/*
 * Asix callbacks
 */
static int asix_init(struct eth_device *eth, bd_t *bd)
{
	int embd_phy;
	unsigned char buf[ETH_ALEN];
	u16 rx_ctl;
	struct ueth_data	*dev = (struct ueth_data *)eth->priv;
	int timeout = 0;
#define TIMEOUT_RESOLUTION 50	/* ms */
	int link_detected;

	debug("** %s()\n", __func__);

	if (asix_write_gpio(dev,
			AX_GPIO_RSE | AX_GPIO_GPO_2 | AX_GPIO_GPO2EN, 5) < 0)
		goto out_err;

	/* 0x10 is the phy id of the embedded 10/100 ethernet phy */
	embd_phy = ((asix_get_phy_addr(dev) & 0x1f) == 0x10 ? 1 : 0);
	if (asix_write_cmd(dev, AX_CMD_SW_PHY_SELECT,
				embd_phy, 0, 0, NULL) < 0) {
		debug("Select PHY #1 failed\n");
		goto out_err;
	}

	if (asix_sw_reset(dev, AX_SWRESET_IPPD | AX_SWRESET_PRL) < 0)
		goto out_err;

	if (asix_sw_reset(dev, AX_SWRESET_CLEAR) < 0)
		goto out_err;

	if (embd_phy) {
		if (asix_sw_reset(dev, AX_SWRESET_IPRL) < 0)
			goto out_err;
	} else {
		if (asix_sw_reset(dev, AX_SWRESET_PRTE) < 0)
			goto out_err;
	}

	rx_ctl = asix_read_rx_ctl(dev);
	debug("RX_CTL is 0x%04x after software reset\n", rx_ctl);
	if (asix_write_rx_ctl(dev, 0x0000) < 0)
		goto out_err;

	rx_ctl = asix_read_rx_ctl(dev);
	debug("RX_CTL is 0x%04x setting to 0x0000\n", rx_ctl);

	/* Get the MAC address */
	if (asix_read_cmd(dev, AX_CMD_READ_NODE_ID,
				0, 0, ETH_ALEN, buf) < 0) {
		debug("Failed to read MAC address.\n");
		goto out_err;
	}
	memcpy(eth->enetaddr, buf, ETH_ALEN);
	debug("MAC %02x:%02x:%02x:%02x:%02x:%02x\n",
		eth->enetaddr[0], eth->enetaddr[1],
		eth->enetaddr[2], eth->enetaddr[3],
		eth->enetaddr[4], eth->enetaddr[5]);

	dev->phy_id = asix_get_phy_addr(dev);
	if (dev->phy_id < 0)
		debug("Failed to read phy id\n");

	if (asix_sw_reset(dev, AX_SWRESET_PRL) < 0)
		goto out_err;

	if (asix_sw_reset(dev, AX_SWRESET_IPRL | AX_SWRESET_PRL) < 0)
		goto out_err;

	asix_mdio_write(dev, dev->phy_id, MII_BMCR, BMCR_RESET);
	asix_mdio_write(dev, dev->phy_id, MII_ADVERTISE,
			ADVERTISE_ALL | ADVERTISE_CSMA);
	mii_nway_restart(dev);

	if (asix_write_medium_mode(dev, AX88772_MEDIUM_DEFAULT) < 0)
		goto out_err;

	if (asix_write_cmd(dev, AX_CMD_WRITE_IPG0,
				AX88772_IPG0_DEFAULT | AX88772_IPG1_DEFAULT,
				AX88772_IPG2_DEFAULT, 0, NULL) < 0) {
		debug("Write IPG,IPG1,IPG2 failed\n");
		goto out_err;
	}

	if (asix_write_rx_ctl(dev, AX_DEFAULT_RX_CTL) < 0)
		goto out_err;

	do {
		link_detected = asix_mdio_read(dev, dev->phy_id, MII_BMSR) &
			BMSR_LSTATUS;
		if (!link_detected) {
			if (timeout == 0)
				printf("Waiting for Ethernet connection... ");
			udelay(TIMEOUT_RESOLUTION * 1000);
			timeout += TIMEOUT_RESOLUTION;
		}
	} while (!link_detected && timeout < PHY_CONNECT_TIMEOUT);
	if (link_detected) {
		if (timeout != 0)
			printf("done.\n");
	} else {
		printf("unable to connect.\n");
		goto out_err;
	}

	return 0;
out_err:
	return -1;
}

static int asix_send(struct eth_device *eth, volatile void *packet, int length)
{
	struct ueth_data *dev = (struct ueth_data *)eth->priv;
	int err;
	u32 packet_len;
	int actual_len;
	unsigned char msg[PKTSIZE + sizeof(packet_len)];

	debug("** %s(), len %d\n", __func__, length);

	packet_len = (((length) ^ 0x0000ffff) << 16) + (length);
	cpu_to_le32s(&packet_len);

	memcpy(msg, &packet_len, sizeof(packet_len));
	memcpy(msg + sizeof(packet_len), (void *)packet, length);
	if (length & 1)
		length++;

	err = usb_bulk_msg(dev->pusb_dev,
				usb_sndbulkpipe(dev->pusb_dev, dev->ep_out),
				(void *)msg,
				length + sizeof(packet_len),
				&actual_len,
				USB_BULK_SEND_TIMEOUT);
	debug("Tx: len = %u, actual = %u, err = %d\n",
			length + sizeof(packet_len), actual_len, err);

	return err;
}

static int asix_recv(struct eth_device *eth)
{
	struct ueth_data *dev = (struct ueth_data *)eth->priv;
	static unsigned char  recv_buf[AX_RX_URB_SIZE];
	unsigned char *buf_ptr;
	int err;
	int actual_len;
	u32 packet_len;

	debug("** %s()\n", __func__);

	err = usb_bulk_msg(dev->pusb_dev,
				usb_rcvbulkpipe(dev->pusb_dev, dev->ep_in),
				(void *)recv_buf,
				AX_RX_URB_SIZE,
				&actual_len,
				USB_BULK_RECV_TIMEOUT);
	debug("Rx: len = %u, actual = %u, err = %d\n", AX_RX_URB_SIZE,
		actual_len, err);
	if (err != 0) {
		debug("Rx: failed to receive\n");
		return -1;
	}
	if (actual_len > AX_RX_URB_SIZE) {
		debug("Rx: received too many bytes %d\n", actual_len);
		return -1;
	}

	buf_ptr = recv_buf;
	while (actual_len > 0) {
		/*
		 * 1st 4 bytes contain the length of the actual data as two
		 * complementary 16-bit words. Extract the length of the data.
		 */
		if (actual_len < sizeof(packet_len)) {
			debug("Rx: incomplete packet length\n");
			return -1;
		}
		memcpy(&packet_len, buf_ptr, sizeof(packet_len));
		le32_to_cpus(&packet_len);
		if (((packet_len >> 16) ^ 0xffff) != (packet_len & 0xffff)) {
			debug("Rx: malformed packet length: %#x (%#x:%#x)\n",
			      packet_len, (packet_len >> 16) ^ 0xffff,
			      packet_len & 0xffff);
			return -1;
		}
		packet_len = packet_len & 0xffff;
		if (packet_len > actual_len - sizeof(packet_len)) {
			debug("Rx: too large packet: %d\n", packet_len);
			return -1;
		}

		/* Notify net stack */
		NetReceive(buf_ptr + sizeof(packet_len), packet_len);

		/* Adjust for next iteration. Packets are padded to 16-bits */
		if (packet_len & 1)
			packet_len++;
		actual_len -= sizeof(packet_len) + packet_len;
		buf_ptr += sizeof(packet_len) + packet_len;
	}

	return err;
}

static void asix_halt(struct eth_device *eth)
{
	debug("** %s()\n", __func__);
}

/*
 * Asix probing functions
 */
void asix_eth_before_probe(void)
{
	curr_eth_dev = 0;
}

struct asix_dongle {
	unsigned short vendor;
	unsigned short product;
};

static struct asix_dongle asix_dongles[] = {
	{ 0x05ac, 0x1402 },	/* Apple USB Ethernet Adapter */
	{ 0x07d1, 0x3c05 },	/* D-Link DUB-E100 H/W Ver B1 */
	{ 0x0b95, 0x772a },	/* Cables-to-Go USB Ethernet Adapter */
	{ 0x0b95, 0x7720 },	/* Trendnet TU2-ET100 V3.0R */
	{ 0x0b95, 0x1720 },	/* SMC */
	{ 0x0db0, 0xa877 },	/* MSI - ASIX 88772a */
	{ 0x13b1, 0x0018 },	/* Linksys 200M v2.1 */
	{ 0x1557, 0x7720 },	/* 0Q0 cable ethernet */
	{ 0x2001, 0x3c05 },	/* DLink DUB-E100 H/W Ver B1 Alternate */
	{ 0x0000, 0x0000 }	/* END - Do not remove */
};

/* Probe to see if a new device is actually an asix device */
int asix_eth_probe(struct usb_device *dev, unsigned int ifnum,
		      struct ueth_data *ss)
{
	struct usb_interface *iface;
	struct usb_interface_descriptor *iface_desc;
	int i;

	/* let's examine the device now */
	iface = &dev->config.if_desc[ifnum];
	iface_desc = &dev->config.if_desc[ifnum].desc;

	for (i = 0; asix_dongles[i].vendor != 0; i++) {
		if (dev->descriptor.idVendor == asix_dongles[i].vendor &&
		    dev->descriptor.idProduct == asix_dongles[i].product)
			/* Found a supported dongle */
			break;
	}

	if (asix_dongles[i].vendor == 0)
		return 0;

	memset(ss, 0, sizeof(struct ueth_data));

	/* At this point, we know we've got a live one */
	debug("\n\nUSB Ethernet device detected: %#04x:%#04x\n",
	      dev->descriptor.idVendor, dev->descriptor.idProduct);

	/* Initialize the ueth_data structure with some useful info */
	ss->ifnum = ifnum;
	ss->pusb_dev = dev;
	ss->subclass = iface_desc->bInterfaceSubClass;
	ss->protocol = iface_desc->bInterfaceProtocol;

	/*
	 * We are expecting a minimum of 3 endpoints - in, out (bulk), and
	 * int. We will ignore any others.
	 */
	for (i = 0; i < iface_desc->bNumEndpoints; i++) {
		/* is it an BULK endpoint? */
		if ((iface->ep_desc[i].bmAttributes &
		     USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_BULK) {
			if (iface->ep_desc[i].bEndpointAddress & USB_DIR_IN)
				ss->ep_in = iface->ep_desc[i].bEndpointAddress &
					USB_ENDPOINT_NUMBER_MASK;
			else
				ss->ep_out =
					iface->ep_desc[i].bEndpointAddress &
					USB_ENDPOINT_NUMBER_MASK;
		}

		/* is it an interrupt endpoint? */
		if ((iface->ep_desc[i].bmAttributes &
		    USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT) {
			ss->ep_int = iface->ep_desc[i].bEndpointAddress &
				USB_ENDPOINT_NUMBER_MASK;
			ss->irqinterval = iface->ep_desc[i].bInterval;
		}
	}
	debug("Endpoints In %d Out %d Int %d\n",
		  ss->ep_in, ss->ep_out, ss->ep_int);

	/* Do some basic sanity checks, and bail if we find a problem */
	if (usb_set_interface(dev, iface_desc->bInterfaceNumber, 0) ||
	    !ss->ep_in || !ss->ep_out || !ss->ep_int) {
		debug("Problems with device\n");
		return 0;
	}
	dev->privptr = (void *)ss;
	return 1;
}

int asix_eth_get_info(struct usb_device *dev, struct ueth_data *ss,
				struct eth_device *eth)
{
	if (!eth) {
		debug("%s: missing parameter.\n", __func__);
		return 0;
	}
	sprintf(eth->name, "%s%d", ASIX_BASE_NAME, curr_eth_dev++);
	eth->init = asix_init;
	eth->send = asix_send;
	eth->recv = asix_recv;
	eth->halt = asix_halt;
	eth->priv = ss;

	return 1;
}