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/*
* Copyright (C) 2015-2016 Freie Universität Berlin
* 2016 Inria
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup drivers_cc2420
* @{
*
* @file
* @brief Implementation of public functions for cc2420 driver
*
* @author Thomas Eichinger <thomas.eichinger@fu-berlin.de>
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*
* @}
*/
#include "luid.h"
#include "byteorder.h"
#include "net/ieee802154.h"
#include "net/gnrc.h"
#include "cc2420_internal.h"
#include "cc2420_netdev.h"
#include "cc2420_registers.h"
#define ENABLE_DEBUG (0)
#include "debug.h"
void cc2420_setup(cc2420_t * dev, const cc2420_params_t *params)
{
/* set pointer to the devices netdev functions */
dev->netdev.netdev.driver = &cc2420_driver;
/* pull in device configuration parameters */
memcpy(&dev->params, params, sizeof(cc2420_params_t));
dev->state = CC2420_STATE_IDLE;
/* reset device descriptor fields */
dev->options = 0;
}
int cc2420_init(cc2420_t *dev)
{
uint16_t reg;
uint8_t addr[8];
/* reset options and sequence number */
dev->netdev.seq = 0;
dev->netdev.flags = 0;
/* set default address, channel, PAN ID, and TX power */
luid_get(addr, sizeof(addr));
/* make sure we mark the address as non-multicast and not globally unique */
addr[0] &= ~(0x01);
addr[0] |= 0x02;
cc2420_set_addr_short(dev, &addr[6]);
cc2420_set_addr_long(dev, addr);
cc2420_set_pan(dev, CC2420_PANID_DEFAULT);
cc2420_set_chan(dev, CC2420_CHAN_DEFAULT);
cc2420_set_txpower(dev, CC2420_TXPOWER_DEFAULT);
/* set default options */
cc2420_set_option(dev, CC2420_OPT_AUTOACK, true);
cc2420_set_option(dev, CC2420_OPT_CSMA, true);
cc2420_set_option(dev, CC2420_OPT_TELL_TX_START, true);
cc2420_set_option(dev, CC2420_OPT_TELL_RX_END, true);
#ifdef MODULE_NETSTATS_L2
cc2420_set_option(dev, CC2420_OPT_TELL_RX_END, true);
#endif
/* set default protocol*/
#ifdef MODULE_GNRC_SIXLOWPAN
dev->netdev.proto = GNRC_NETTYPE_SIXLOWPAN;
#elif MODULE_GNRC
dev->netdev.proto = GNRC_NETTYPE_UNDEF;
#endif
/* change default RX bandpass filter to 1.3uA (as recommended) */
reg = cc2420_reg_read(dev, CC2420_REG_RXCTRL1);
reg |= CC2420_RXCTRL1_RXBPF_LOCUR;
cc2420_reg_write(dev, CC2420_REG_RXCTRL1, reg);
/* set the FIFOP threshold to maximum. */
cc2420_reg_write(dev, CC2420_REG_IOCFG0, CC2420_PKT_MAXLEN);
/* turn off "Security enable" (page 33). */
reg = cc2420_reg_read(dev, CC2420_REG_SECCTRL0);
reg &= ~CC2420_SECCTRL0_RXFIFO_PROT;
cc2420_reg_write(dev, CC2420_REG_SECCTRL0, reg);
/* set preamble length to 3 leading zero byte */
/* and turn on hardware CRC generation */
reg = cc2420_reg_read(dev, CC2420_REG_MDMCTRL0);
reg &= ~(CC2420_MDMCTRL0_PREAMBLE_M);
reg |= CC2420_MDMCTRL0_PREAMBLE_3B;
reg |= CC2420_MDMCTRL0_AUTOCRC;
cc2420_reg_write(dev, CC2420_REG_MDMCTRL0, reg);
/* go into RX state */
cc2420_set_state(dev, CC2420_GOTO_RX);
return 0;
}
bool cc2420_cca(cc2420_t *dev)
{
while (!(cc2420_status(dev) & CC2420_STATUS_RSSI_VALID)) {}
return gpio_read(dev->params.pin_cca);
}
size_t cc2420_send(cc2420_t *dev, const struct iovec *data, unsigned count)
{
size_t n = cc2420_tx_prepare(dev, data, count);
if ((n > 0) && !(dev->options & CC2420_OPT_PRELOADING)) {
cc2420_tx_exec(dev);
}
return n;
}
size_t cc2420_tx_prepare(cc2420_t *dev, const struct iovec *data, unsigned count)
{
size_t pkt_len = 2; /* include the FCS (frame check sequence) */
/* wait for any ongoing transmissions to be finished */
DEBUG("cc2420: tx_exec: waiting for any ongoing transmission\n");
while (cc2420_get_state(dev) & NETOPT_STATE_TX) {}
/* get and check the length of the packet */
for (unsigned i = 0; i < count; i++) {
pkt_len += data[i].iov_len;
}
if (pkt_len >= CC2420_PKT_MAXLEN) {
DEBUG("cc2420: tx_prep: unable to send, pkt too large\n");
return 0;
}
/* flush TX FIFO and write new packet to it */
cc2420_strobe(dev, CC2420_STROBE_FLUSHTX);
/* push packet length to TX FIFO */
cc2420_fifo_write(dev, (uint8_t *)&pkt_len, 1);
/* push packet to TX FIFO */
for (int i = 0; i < count; i++) {
cc2420_fifo_write(dev, (uint8_t *)data[i].iov_base, data[i].iov_len);
}
DEBUG("cc2420: tx_prep: loaded %i byte into the TX FIFO\n", (int)pkt_len);
return pkt_len;
}
void cc2420_tx_exec(cc2420_t *dev)
{
/* trigger the transmission */
if (dev->options & CC2420_OPT_TELL_TX_START) {
dev->netdev.netdev.event_callback(&dev->netdev.netdev,
NETDEV_EVENT_TX_STARTED);
}
DEBUG("cc2420: tx_exec: TX_START\n");
if (dev->options & CC2420_OPT_CSMA) {
DEBUG("cc2420: tx_exec: triggering TX with CCA\n");
cc2420_strobe(dev, CC2420_STROBE_TXONCCA);
}
else {
DEBUG("cc2420: tx_exec: triggering TX without CCA\n");
cc2420_strobe(dev, CC2420_STROBE_TXON);
}
}
int cc2420_rx(cc2420_t *dev, uint8_t *buf, size_t max_len, void *info)
{
uint8_t len;
uint8_t crc_corr;
/* without a provided buffer, only readout the length and return it */
if (buf == NULL) {
/* get the packet length (without dropping it) (first byte in RX FIFO) */
cc2420_ram_read(dev, CC2420_RAM_RXFIFO, &len, 1);
len -= 2; /* subtract RSSI and FCF */
DEBUG("cc2420: recv: packet of length %i in RX FIFO\n", (int)len);
}
else {
/* read length byte */
cc2420_fifo_read(dev, &len, 1);
len -= 2; /* subtract RSSI and FCF */
/* if a buffer is given, read (and drop) the packet */
len = (len > max_len) ? max_len : len;
/* read fifo contents */
DEBUG("cc2420: recv: reading %i byte of the packet\n", (int)len);
cc2420_fifo_read(dev, buf, len);
uint8_t rssi;
cc2420_fifo_read(dev, &rssi, 1);
DEBUG("cc2420: recv: RSSI is %i\n", (int)rssi);
/* fetch and check if CRC_OK bit (MSB) is set */
cc2420_fifo_read(dev, &crc_corr, 1);
if (!(crc_corr & 0x80)) {
DEBUG("cc2420: recv: CRC_OK bit not set, dropping packet\n");
/* drop the corrupted frame from the RXFIFO */
len = 0;
}
/* finally flush the FIFO */
cc2420_strobe(dev, CC2420_STROBE_FLUSHRX);
cc2420_strobe(dev, CC2420_STROBE_FLUSHRX);
}
return (int)len;
}