g2100.c

/*****************************************************************************

  Filename:		g2100.c
  Description:	Driver for the ZeroG Wireless G2100 series devices

 *****************************************************************************

  Driver for the WiShield 1.0 wireless devices

  Copyright(c) 2009 Async Labs Inc. All rights reserved.

  This program is free software; you can redistribute it and/or modify it
  under the terms of version 2 of the GNU General Public License as
  published by the Free Software Foundation.

  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.

  Contact Information:
  <asynclabs@asynclabs.com>

   Author               Date        Comment
  ----------------------------------------------------------------------------
   AsyncLabs			02/25/2009	Initial port
   AsyncLabs			05/29/2009	Adding support for new library

 *****************************************************************************/

#include <string.h>
#include "witypes.h"
#include "config.h"
#include "g2100.h"
#include "spi.h"
#include "global-conf.h"

static U8 mac[6];
static U8 zg_conn_status;

static U8 hdr[5];
static U8 intr_occured;
static U8 intr_valid;
static U8 zg_drv_state;
static U8 tx_ready;
static U8 rx_ready;
static U8 cnf_pending;
static U8* zg_buf;
static U16 zg_buf_len;

static U8 wpa_psk_key[32];

void zg_init()
{
	U8 clr;

	ZG2100_SpiInit();
	clr = SPSR;
	clr = SPDR;

	intr_occured = 0;
	intr_valid = 0;
	zg_drv_state = DRV_STATE_INIT;
	zg_conn_status = 0;
	tx_ready = 0;
	rx_ready = 0;
	cnf_pending = 0;
	zg_buf = uip_buf;
	zg_buf_len = UIP_BUFSIZE;

	zg_chip_reset();
	zg_interrupt2_reg();
	zg_interrupt_reg(0xff, 0);
	zg_interrupt_reg(0x80|0x40, 1);

	ssid_len = (U8)strlen(ssid);
	security_passphrase_len = (U8)strlen(security_passphrase);
}

void spi_transfer(volatile U8* buf, U16 len, U8 toggle_cs)
{
	U16 i;

	ZG2100_CSoff();

	for (i = 0; i < len; i++) {
		ZG2100_SpiSendData(buf[i]);		// Start the transmission
		buf[i] = ZG2100_SpiRecvData();
	}

	if (toggle_cs)
		ZG2100_CSon();

	return;
}

void zg_chip_reset()
{
	U8 loop_cnt = 0;

	do {
		// write reset register addr
		hdr[0] = ZG_INDEX_ADDR_REG;
		hdr[1] = 0x00;
		hdr[2] = ZG_RESET_REG;
		spi_transfer(hdr, 3, 1);

		hdr[0] = ZG_INDEX_DATA_REG;
		hdr[1] = (loop_cnt == 0)?(0x80):(0x0f);
		hdr[2] = 0xff;
		spi_transfer(hdr, 3, 1);
	} while(loop_cnt++ < 1);

	// write reset register data
	hdr[0] = ZG_INDEX_ADDR_REG;
	hdr[1] = 0x00;
	hdr[2] = ZG_RESET_STATUS_REG;
	spi_transfer(hdr, 3, 1);

	do {
		hdr[0] = 0x40 | ZG_INDEX_DATA_REG;
		hdr[1] = 0x00;
		hdr[2] = 0x00;
		spi_transfer(hdr, 3, 1);
	} while((hdr[1] & ZG_RESET_MASK) == 0);

	do {
		hdr[0] = 0x40 | ZG_BYTE_COUNT_REG;
		hdr[1] = 0x00;
		hdr[2] = 0x00;
		spi_transfer(hdr, 3, 1);
	} while((hdr[1] == 0) && (hdr[2] == 0));
}

void zg_interrupt2_reg()
{
	// read the interrupt2 mask register
	hdr[0] = 0x40 | ZG_INTR2_MASK_REG;
	hdr[1] = 0x00;
	hdr[2] = 0x00;
	spi_transfer(hdr, 3, 1);

	// modify the interrupt mask value and re-write the value to the interrupt
	// mask register clearing the interrupt register first
	hdr[0] = ZG_INTR2_REG;
	hdr[1] = 0xff;
	hdr[2] = 0xff;
	hdr[3] = 0;
	hdr[4] = 0;
	spi_transfer(hdr, 5, 1);

	return;
}

void zg_interrupt_reg(U8 mask, U8 state)
{
	// read the interrupt register
	hdr[0] = 0x40 | ZG_INTR_MASK_REG;
	hdr[1] = 0x00;
	spi_transfer(hdr, 2, 1);

	// now regBuf[0] contains the current setting for the
	// interrupt mask register
	// this is to clear any currently set interrupts of interest
	hdr[0] = ZG_INTR_REG;
	hdr[2] = (hdr[1] & ~mask) | ( (state == 0)? 0 : mask );
	hdr[1] = mask;
	spi_transfer(hdr, 3, 1);

	return;
}

void zg_isr()
{
	ZG2100_ISR_DISABLE();
	intr_occured = 1;
}

void zg_process_isr()
{
	U8 intr_state = 0;
	U8 next_cmd = 0;

	hdr[0] = 0x40 | ZG_INTR_REG;
	hdr[1] = 0x00;
	hdr[2] = 0x00;
	spi_transfer(hdr, 3, 1);

	intr_state = ZG_INTR_ST_RD_INTR_REG;

	do {
		switch(intr_state) {
		case ZG_INTR_ST_RD_INTR_REG:
		{
			U8 intr_val = hdr[1] & hdr[2];

			if ( (intr_val & ZG_INTR_MASK_FIFO1) == ZG_INTR_MASK_FIFO1) {
				hdr[0] = ZG_INTR_REG;
				hdr[1] = ZG_INTR_MASK_FIFO1;
				spi_transfer(hdr, 2, 1);

				intr_state = ZG_INTR_ST_WT_INTR_REG;
				next_cmd = ZG_BYTE_COUNT_FIFO1_REG;
			}
			else if ( (intr_val & ZG_INTR_MASK_FIFO0) == ZG_INTR_MASK_FIFO0) {
				hdr[0] = ZG_INTR_REG;
				hdr[1] = ZG_INTR_MASK_FIFO0;
				spi_transfer(hdr, 2, 1);

				intr_state = ZG_INTR_ST_WT_INTR_REG;
				next_cmd = ZG_BYTE_COUNT_FIFO0_REG;
			}
			else if (intr_val) {
				intr_state = 0;
			}
			else {
				intr_state = 0;
			}

			break;
		}
		case ZG_INTR_ST_WT_INTR_REG:
		{
			hdr[0] = 0x40 | next_cmd;
			hdr[1] = 0x00;
			hdr[2] = 0x00;
			spi_transfer(hdr, 3, 1);

			intr_state = ZG_INTR_ST_RD_CTRL_REG;
			break;
		}
		// this is the NEW CODE from this thread: http://asynclabs.com/forums/viewtopic.php?f=23&t=432&hilit=large+packet#p2980
		case ZG_INTR_ST_RD_CTRL_REG:
	      {
		    // Get the size of the incoming packet
		 U16 rx_byte_cnt = (0x0000 | (hdr[1] << 8) | hdr[2]) & 0x0fff;
	
		 // Check if our buffer is large enough for packet
		    if(rx_byte_cnt < (U16)UIP_BUFSIZE) {
		    zg_buf[0] = ZG_CMD_RD_FIFO;
		    // Copy ZG2100 buffer contents into zg_buf (uip_buf)             
		    spi_transfer(zg_buf, rx_byte_cnt + 1, 1);
		    // interrupt from zg2100 was meaningful and requires further processing
		    intr_valid = 1;
		 }
		 else {
		    // Too Big, ignore it and continue
		    intr_valid = 0; 
		 }
	
		 // Tell ZG2100 we're done reading from its buffer
		 hdr[0] = ZG_CMD_RD_FIFO_DONE;
		 spi_transfer(hdr, 1, 1);
		    
		 // Done reading interrupt from ZG2100
		 intr_state = 0;
		 break;
  	      }
		/*case ZG_INTR_ST_RD_CTRL_REG:
		{
			U16 rx_byte_cnt = (0x0000 | (hdr[1] << 8) | hdr[2]) & 0x0fff;

			zg_buf[0] = ZG_CMD_RD_FIFO;
			spi_transfer(zg_buf, rx_byte_cnt + 1, 1);

			hdr[0] = ZG_CMD_RD_FIFO_DONE;
			spi_transfer(hdr, 1, 1);

			intr_valid = 1;

			intr_state = 0;
			break;
		}*/
		}
	} while (intr_state);
#ifdef USE_DIG8_INTR
	// PCINT0 supports only edge triggered INT
	if (PORTB & 0x01) {
		intr_occured = 0;
		ZG2100_ISR_ENABLE();
	}
	else {
		intr_occured = 1;
	}
#else
	intr_occured = 0;
	ZG2100_ISR_ENABLE();
#endif
}

void zg_send(U8* buf, U16 len)
{
	hdr[0] = ZG_CMD_WT_FIFO_DATA;
	hdr[1] = ZG_MAC_TYPE_TXDATA_REQ;
	hdr[2] = ZG_MAC_SUBTYPE_TXDATA_REQ_STD;
	hdr[3] = 0x00;
	hdr[4] = 0x00;
	spi_transfer(hdr, 5, 0);

	buf[6] = 0xaa;
	buf[7] = 0xaa;
	buf[8] = 0x03;
	buf[9] = buf[10] = buf[11] = 0x00;
	spi_transfer(buf, len, 1);

	hdr[0] = ZG_CMD_WT_FIFO_DONE;
	spi_transfer(hdr, 1, 1);
}

void zg_recv(U8* buf, U16* len)
{
	zg_rx_data_ind_t* ptr = (zg_rx_data_ind_t*)&(zg_buf[3]);
	*len = ZGSTOHS( ptr->dataLen );

	memcpy(&zg_buf[0], &zg_buf[5], 6);
	memcpy(&zg_buf[6], &zg_buf[11], 6);
	memcpy(&zg_buf[12], &zg_buf[29], *len);

	*len += 12;
}

U16 zg_get_rx_status()
{
	if (rx_ready) {
		rx_ready = 0;
		return zg_buf_len;
	}
	else {
		return 0;
	}
}

void zg_clear_rx_status()
{
	rx_ready = 0;
}

void zg_set_tx_status(U8 status)
{
	tx_ready = status;
}

U8 zg_get_conn_state()
{
	return zg_conn_status;
}

void zg_set_buf(U8* buf, U16 buf_len)
{
	zg_buf = buf;
	zg_buf_len = buf_len;
}

U8* zg_get_mac()
{
	return mac;
}

void zg_write_wep_key(U8* cmd_buf)
{
	zg_wep_key_req_t* cmd = (zg_wep_key_req_t*)cmd_buf;

	cmd->slot = 3;		// WEP key slot
	cmd->keyLen = security_passphrase_len/2;	// SAVRAJ EDIT! // Key length: 5 bytes (64-bit WEP); 13 bytes (128-bit WEP)
	cmd->defID = 0;		// Default key ID: Key 0, 1, 2, 3
	cmd->ssidLen = ssid_len;
	memset(cmd->ssid, 0x00, 32);
	memcpy(cmd->ssid, ssid, ssid_len);
	memcpy(cmd->key, wep_keys, ZG_MAX_ENCRYPTION_KEYS * ZG_MAX_ENCRYPTION_KEY_SIZE);

	return;
}

static void zg_calc_psk_key(U8* cmd_buf)
{
	zg_psk_calc_req_t* cmd = (zg_psk_calc_req_t*)cmd_buf;

	cmd->configBits = 0;
	cmd->phraseLen = security_passphrase_len;
	cmd->ssidLen = ssid_len;
	cmd->reserved = 0;
	memset(cmd->ssid, 0x00, 32);
	memcpy(cmd->ssid, ssid, ssid_len);
	memset(cmd->passPhrase, 0x00, 64);
	memcpy(cmd->passPhrase, security_passphrase, security_passphrase_len);

	return;
}

static void zg_write_psk_key(U8* cmd_buf)
{
	zg_pmk_key_req_t* cmd = (zg_pmk_key_req_t*)cmd_buf;

	cmd->slot = 0;	// WPA/WPA2 PSK slot
	cmd->ssidLen = ssid_len;
	memset(cmd->ssid, 0x00, 32);
	memcpy(cmd->ssid, ssid, cmd->ssidLen);
	memcpy(cmd->keyData, wpa_psk_key, ZG_MAX_PMK_LEN);

	return;
}

void zg_drv_process()
{
	// TX frame
	if (tx_ready && !cnf_pending) {
		zg_send(zg_buf, zg_buf_len);
		tx_ready = 0;
		cnf_pending = 1;
	}

	// process interrupt
	if (intr_occured) {
		zg_process_isr();
	}

	if (intr_valid) {
		switch (zg_buf[1]) {
		case ZG_MAC_TYPE_TXDATA_CONFIRM:
			cnf_pending = 0;
			break;
		case ZG_MAC_TYPE_MGMT_CONFIRM:
			if (zg_buf[3] == ZG_RESULT_SUCCESS) {
				switch (zg_buf[2]) {
				case ZG_MAC_SUBTYPE_MGMT_REQ_GET_PARAM:
					mac[0] = zg_buf[7];
					mac[1] = zg_buf[8];
					mac[2] = zg_buf[9];
					mac[3] = zg_buf[10];
					mac[4] = zg_buf[11];
					mac[5] = zg_buf[12];
					zg_drv_state = DRV_STATE_SETUP_SECURITY;
					break;
				case ZG_MAC_SUBTYPE_MGMT_REQ_WEP_KEY:
					zg_drv_state = DRV_STATE_ENABLE_CONN_MANAGE;
					break;
				case ZG_MAC_SUBTYPE_MGMT_REQ_CALC_PSK:
					memcpy(wpa_psk_key, ((zg_psk_calc_cnf_t*)&zg_buf[3])->psk, 32);
					zg_drv_state = DRV_STATE_INSTALL_PSK;
					break;
				case ZG_MAC_SUBTYPE_MGMT_REQ_PMK_KEY:
					zg_drv_state = DRV_STATE_ENABLE_CONN_MANAGE;
					break;
				case ZG_MAC_SUBTYPE_MGMT_REQ_CONNECT_MANAGE:
					zg_drv_state = DRV_STATE_START_CONN;
					break;
				case ZG_MAC_SUBTYPE_MGMT_REQ_CONNECT:
					LEDConn_on();
					zg_conn_status = 1;	// connected
					break;
				default:
					break;
				}
			}
			break;
		case ZG_MAC_TYPE_RXDATA_INDICATE:
			zg_drv_state = DRV_STATE_PROCESS_RX;
			break;
		case ZG_MAC_TYPE_MGMT_INDICATE:
			switch (zg_buf[2]) {
			case ZG_MAC_SUBTYPE_MGMT_IND_DISASSOC:
			case ZG_MAC_SUBTYPE_MGMT_IND_DEAUTH:
				LEDConn_off();
				zg_conn_status = 0;	// lost connection

				//try to reconnect
				zg_drv_state = DRV_STATE_START_CONN;
				break;
			case ZG_MAC_SUBTYPE_MGMT_IND_CONN_STATUS:
				{
					U16 status = (((U16)(zg_buf[3]))<<8)|zg_buf[4];

					if (status == 1 || status == 5) {
						LEDConn_off();
						zg_conn_status = 0;	// not connected
					}
					else if (status == 2 || status == 6) {
						LEDConn_on();
						zg_conn_status = 1;	// connected
					}
				}
				break;
			}
			break;
		}

		intr_valid = 0;
	}

	switch (zg_drv_state) {
	case DRV_STATE_INIT:
		zg_drv_state = DRV_STATE_GET_MAC;
		break;
	case DRV_STATE_GET_MAC:
		// get MAC address
		zg_buf[0] = ZG_CMD_WT_FIFO_MGMT;
		zg_buf[1] = ZG_MAC_TYPE_MGMT_REQ;
		zg_buf[2] = ZG_MAC_SUBTYPE_MGMT_REQ_GET_PARAM;
		zg_buf[3] = 0;
		zg_buf[4] = ZG_PARAM_MAC_ADDRESS;
		spi_transfer(zg_buf, 5, 1);

		zg_buf[0] = ZG_CMD_WT_FIFO_DONE;
		spi_transfer(zg_buf, 1, 1);

		zg_drv_state = DRV_STATE_IDLE;
		break;
	case DRV_STATE_SETUP_SECURITY:
		switch (security_type) {
		case ZG_SECURITY_TYPE_NONE:
			zg_drv_state = DRV_STATE_ENABLE_CONN_MANAGE;
			break;
		case ZG_SECURITY_TYPE_WEP:
			// Install all four WEP keys on G2100
			zg_buf[0] = ZG_CMD_WT_FIFO_MGMT;
			zg_buf[1] = ZG_MAC_TYPE_MGMT_REQ;
			zg_buf[2] = ZG_MAC_SUBTYPE_MGMT_REQ_WEP_KEY;
			zg_write_wep_key(&zg_buf[3]);
			spi_transfer(zg_buf, ZG_WEP_KEY_REQ_SIZE+3, 1);

			zg_buf[0] = ZG_CMD_WT_FIFO_DONE;
			spi_transfer(zg_buf, 1, 1);

			zg_drv_state = DRV_STATE_IDLE;
			break;
		case ZG_SECURITY_TYPE_WPA:
		case ZG_SECURITY_TYPE_WPA2:
			// Initiate PSK calculation on G2100
			zg_buf[0] = ZG_CMD_WT_FIFO_MGMT;
			zg_buf[1] = ZG_MAC_TYPE_MGMT_REQ;
			zg_buf[2] = ZG_MAC_SUBTYPE_MGMT_REQ_CALC_PSK;
			zg_calc_psk_key(&zg_buf[3]);
			spi_transfer(zg_buf, ZG_PSK_CALC_REQ_SIZE+3, 1);

			zg_buf[0] = ZG_CMD_WT_FIFO_DONE;
			spi_transfer(zg_buf, 1, 1);

			zg_drv_state = DRV_STATE_IDLE;
			break;
		default:
			break;
		}
		break;
	case DRV_STATE_INSTALL_PSK:
		// Install the PSK key on G2100
		zg_buf[0] = ZG_CMD_WT_FIFO_MGMT;
		zg_buf[1] = ZG_MAC_TYPE_MGMT_REQ;
		zg_buf[2] = ZG_MAC_SUBTYPE_MGMT_REQ_PMK_KEY;
		zg_write_psk_key(&zg_buf[3]);
		spi_transfer(zg_buf, ZG_PMK_KEY_REQ_SIZE+3, 1);

		zg_buf[0] = ZG_CMD_WT_FIFO_DONE;
		spi_transfer(zg_buf, 1, 1);

		zg_drv_state = DRV_STATE_IDLE;
		break;
	case DRV_STATE_ENABLE_CONN_MANAGE:
		// enable connection manager
		zg_buf[0] = ZG_CMD_WT_FIFO_MGMT;
		zg_buf[1] = ZG_MAC_TYPE_MGMT_REQ;
		zg_buf[2] = ZG_MAC_SUBTYPE_MGMT_REQ_CONNECT_MANAGE;
		zg_buf[3] = 0x01;	// 0x01 - enable; 0x00 - disable
		zg_buf[4] = 10;		// num retries to reconnect
		zg_buf[5] = 0x10 | 0x02 | 0x01;	// 0x10 -	enable start and stop indication messages
										// 		 	from G2100 during reconnection
										// 0x02 -	start reconnection on receiving a deauthentication
										// 			message from the AP
										// 0x01 -	start reconnection when the missed beacon count
										// 			exceeds the threshold. uses default value of
										//			100 missed beacons if not set during initialization
		zg_buf[6] = 0;
		spi_transfer(zg_buf, 7, 1);

		zg_buf[0] = ZG_CMD_WT_FIFO_DONE;
		spi_transfer(zg_buf, 1, 1);

		zg_drv_state = DRV_STATE_IDLE;
		break;
	case DRV_STATE_START_CONN:
	{
		zg_connect_req_t* cmd = (zg_connect_req_t*)&zg_buf[3];

		// start connection to AP
		zg_buf[0] = ZG_CMD_WT_FIFO_MGMT;
		zg_buf[1] = ZG_MAC_TYPE_MGMT_REQ;
		zg_buf[2] = ZG_MAC_SUBTYPE_MGMT_REQ_CONNECT;

		cmd->secType = security_type;

		cmd->ssidLen = ssid_len;
		memset(cmd->ssid, 0, 32);
		memcpy(cmd->ssid, ssid, ssid_len);

		// units of 100 milliseconds
		cmd->sleepDuration = 0;

		if (wireless_mode == WIRELESS_MODE_INFRA)
			cmd->modeBss = 1;
		else if (wireless_mode == WIRELESS_MODE_ADHOC)
			cmd->modeBss = 2;

		spi_transfer(zg_buf, ZG_CONNECT_REQ_SIZE+3, 1);

		zg_buf[0] = ZG_CMD_WT_FIFO_DONE;
		spi_transfer(zg_buf, 1, 1);

		zg_drv_state = DRV_STATE_IDLE;
		break;
	}
	case DRV_STATE_PROCESS_RX:
		zg_recv(zg_buf, &zg_buf_len);
		rx_ready = 1;

		zg_drv_state = DRV_STATE_IDLE;
		break;
	case DRV_STATE_IDLE:
		break;
	}
}