/****************************************************************************
* drivers/net/enc28j60.c
*
* Copyright (C) 2010 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* References:
* - ENC28J60 Data Sheet, Stand-Alone Ethernet Controller with SPI Interface,
* DS39662C, 2008 Microchip Technology Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#if defined(CONFIG_NET) && defined(CONFIG_ENC28J60_NET)
#include <stdint.h>
#include <stdbool.h>
#include <stding.h>
#include <time.h>
#include <string.h>
#include <debug.h>
#include <wdog.h>
#include <errno.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <nuttx/spi.h>
#include <net/uip/uip.h>
#include <net/uip/uip-arp.h>
#include <net/uip/uip-arch.h>
#include "enc28j60.h"
/****************************************************************************
* Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* All SPI settings can be specifed in the configuration. If not, some
* defaults will be provided.
*
* CONFIG_ENC28J60_OWNBUS - Set if the ENC28J60 is the only active device on
* the SPI bus.
* CONFIG_ENC28J60_SPIMODE - Controls the SPI mode
* CONFIG_ENC28J60_FREQUENCY - Define to use a different bus frequency
* CONFIG_ENC28J60_NINTERFACES - Specifies the number of physical ENC28J60
* devices that will be supported.
*/
#ifdef CONFIG_ENC28J60_SPIMODE
# define CONFIG_ENC28J60_SPIMODE SPIDEV_MODE2
#endif
/* CONFIG_ENC28J60_NINTERFACES determines the number of physical interfaces
* that will be supported.
*/
#ifndef CONFIG_ENC28J60_NINTERFACES
# define CONFIG_ENC28J60_NINTERFACES 1
#endif
/* Timing *******************************************************************/
/* TX poll deley = 1 seconds. CLK_TCK is the number of clock ticks per second */
#define ENC28J60_WDDELAY (1*CLK_TCK)
#define ENC28J60_POLLHSEC (1*2)
/* TX timeout = 1 minute */
#define ENC28J60_TXTIMEOUT (60*CLK_TCK)
/* Misc. Helper Macros ******************************************************/
/* This is a helper pointer for accessing the contents of the Ethernet header */
#define BUF ((struct uip_eth_hdr *)priv->dev.d_buf)
/****************************************************************************
* Private Types
****************************************************************************/
/* The enc28j60_driver_s encapsulates all state information for a single hardware
* interface
*/
struct enc28j60_driver_s
{
bool bifup; /* true:ifup false:ifdown */
uint8_t bank; /* Currently selected bank */
uint16_t nextpkt; /* Next packet address */
WDOG_ID txpoll; /* TX poll timer */
WDOG_ID txtimeout; /* TX timeout timer */
/* This is the contained SPI driver intstance */
FAR struct spi_dev_s *spi;
/* This holds the information visible to uIP/NuttX */
struct uip_driver_s dev; /* Interface understood by uIP */
};
/****************************************************************************
* Private Data
****************************************************************************/
static struct enc28j60_driver_s g_enc28j60[CONFIG_ENC28J60_NINTERFACES];
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Low-level SPI helpers */
static inline void enc28j60_configspi(FAR struct spi_dev_s *spi);
/* Common TX logic */
static int enc28j60_transmit(FAR struct enc28j60_drver_s *priv);
static int enc28j60_uiptxpoll(struct uip_driver_s *dev);
/* Interrupt handling */
static void enc28j60_receive(FAR struct enc28j60_drver_s *priv);
static void enc28j60_txdone(FAR struct enc28j60_drver_s *priv);
static int enc28j60_interrupt(int irq, FAR void *context);
/* Watchdog timer expirations */
static void enc28j60_polltimer(int argc, uint32_t arg, ...);
static void enc28j60_txtimeout(int argc, uint32_t arg, ...);
/* NuttX callback functions */
static int enc28j60_ifup(struct uip_driver_s *dev);
static int enc28j60_ifdown(struct uip_driver_s *dev);
static int enc28j60_txavail(struct uip_driver_s *dev);
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Function: enc28j60_configspi
*
* Description:
* Configure the SPI for use with the ENC28J60
*
****************************************************************************/
static inline void enc28j60_configspi(FAR struct spi_dev_s *spi)
{
/* Configure SPI for the ENC28J60. But only if we own the SPI bus.
* Otherwise, don't bother because it might change.
*/
#ifdef CONFIG_ENC28J60_OWNBUS
SPI_SETMODE(spi, CONFIG_ENC28J60_SPIMODE);
SPI_SETBITS(spi, 8);
#ifdef CONFIG_ENC28J60_FREQUENCY
SPI_SETFREQUENCY(spi, CONFIG_ENC28J60_FREQUENCY)
#endif
#endif
}
/****************************************************************************
* Function: enc28j60_select
*
* Description:
* Select the SPI, locking and re-configuring if necessary
*
****************************************************************************/
#ifdef CONFIG_ENC28J60_OWNBUS
static inline uint8_t enc28j60_select(FAR struct spi_dev_s *spi)
{
/* We own the SPI bus, so just select the chip */
SPI_SELECT(spi, SPIDEV_ETHERNET, true);
}
#else
static uint8_t enc28j60_select(FAR struct spi_dev_s *spi)
{
/* Select ENC2J60 chip (locking the SPI bus in case there are multiple
* devices competing for the SPI bus
*/
SPI_LOCK(spi, true);
SPI_SELECT(spi, SPIDEV_ETHERNET, true);
/* Now make sure that the SPI bus is configured for the ENC28J60 (it
* might have gotten configured for a different device while unlocked)
*/
SPI_SETMODE(spi, CONFIG_ENC28J60_SPIMODE);
SPI_SETBITS(spi, 8);
#ifdef CONFIG_ENC28J60_FREQUENCY
SPI_SETFREQUENCY(spi, CONFIG_ENC28J60_FREQUENCY)
#endif
}
#endif
/****************************************************************************
* Function: enc28j60_deselect
*
* Description:
* De-select the SPI
*
****************************************************************************/
#ifdef CONFIG_ENC28J60_OWNBUS
static inline uint8_t enc28j60_deselect(FAR struct spi_dev_s *spi)
{
/* We own the SPI bus, so just de-select the chip */
SPI_SELECT(spi, SPIDEV_ETHERNET, false);
}
#else
static uint8_t enc28j60_deselect(FAR struct spi_dev_s *spi)
{
/* De-select ENC28J60 chip and relinquish the SPI bus. */
SPI_SELECT(spi, SPIDEV_ETHERNET, false);
SPI_LOCK(spi, false);
}
#endif
/****************************************************************************
* Function: enc28j60_transmit
*
* Description:
* Start hardware transmission. Called either from the txdone interrupt
* handling or from watchdog based polling.
*
* Parameters:
* priv - Reference to the driver state structure
*
* Returned Value:
* OK on success; a negated errno on failure
*
* Assumptions:
*
****************************************************************************/
static int enc28j60_transmit(FAR struct enc28j60_drver_s *priv)
{
/* Verify that the hardware is ready to send another packet */
/* Increment statistics */
/* Disable Ethernet interrupts */
/* Send the packet: address=priv->dev.d_buf, length=priv->dev.d_len */
/* Restore Ethernet interrupts */
/* Setup the TX timeout watchdog (perhaps restarting the timer) */
(void)wd_start(priv->txtimeout, ENC28J60_TXTIMEOUT, enc28j60_txtimeout, 1, (uint32_t)priv);
return OK;
}
/****************************************************************************
* Function: enc28j60_uiptxpoll
*
* Description:
* The transmitter is available, check if uIP has any outgoing packets ready
* to send. This is a callback from uip_poll(). uip_poll() may be called:
*
* 1. When the preceding TX packet send is complete,
* 2. When the preceding TX packet send timesout and the interface is reset
* 3. During normal TX polling
*
* Parameters:
* dev - Reference to the NuttX driver state structure
*
* Returned Value:
* OK on success; a negated errno on failure
*
* Assumptions:
*
****************************************************************************/
static int enc28j60_uiptxpoll(struct uip_driver_s *dev)
{
FAR struct enc28j60_drver_s *priv = (FAR struct enc28j60_drver_s *)dev->d_private;
/* If the polling resulted in data that should be sent out on the network,
* the field d_len is set to a value > 0.
*/
if (priv->dev.d_len > 0)
{
uip_arp_out(&priv->dev);
enc28j60_transmit(priv);
/* Check if there is room in the device to hold another packet. If not,
* return a non-zero value to terminate the poll.
*/
}
/* If zero is returned, the polling will continue until all connections have
* been examined.
*/
return 0;
}
/****************************************************************************
* Function: enc28j60_receive
*
* Description:
* An interrupt was received indicating the availability of a new RX packet
*
* Parameters:
* priv - Reference to the driver state structure
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
static void enc28j60_receive(FAR struct enc28j60_drver_s *priv)
{
do
{
/* Check for errors and update statistics */
/* Check if the packet is a valid size for the uIP buffer configuration */
/* Copy the data data from the hardware to priv->dev.d_buf. Set
* amount of data in priv->dev.d_len
*/
/* We only accept IP packets of the configured type and ARP packets */
#ifdef CONFIG_NET_IPv6
if (BUF->type == HTONS(UIP_ETHTYPE_IP6))
#else
if (BUF->type == HTONS(UIP_ETHTYPE_IP))
#endif
{
uip_arp_ipin();
uip_input(&priv->dev);
/* If the above function invocation resulted in data that should be
* sent out on the network, the field d_len will set to a value > 0.
*/
if (priv->dev.d_len > 0)
{
uip_arp_out(&priv->dev);
enc28j60_transmit(priv);
}
}
else if (BUF->type == htons(UIP_ETHTYPE_ARP))
{
uip_arp_arpin(&priv->dev);
/* If the above function invocation resulted in data that should be
* sent out on the network, the field d_len will set to a value > 0.
*/
if (priv->dev.d_len > 0)
{
enc28j60_transmit(priv);
}
}
}
}
while (); /* While there are more packets to be processed */
}
/****************************************************************************
* Function: enc28j60_txdone
*
* Description:
* An interrupt was received indicating that the last TX packet(s) is done
*
* Parameters:
* priv - Reference to the driver state structure
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
static void enc28j60_txdone(FAR struct enc28j60_drver_s *priv)
{
/* Check for errors and update statistics */
/* If no further xmits are pending, then cancel the TX timeout */
wd_cancel(priv->txtimeout);
/* Then poll uIP for new XMIT data */
(void)uip_poll(&priv->dev, enc28j60_uiptxpoll);
}
/****************************************************************************
* Function: enc28j60_interrupt
*
* Description:
* Hardware interrupt handler
*
* Parameters:
* irq - Number of the IRQ that generated the interrupt
* context - Interrupt register state save info (architecture-specific)
*
* Returned Value:
* OK on success
*
* Assumptions:
*
****************************************************************************/
static int enc28j60_interrupt(int irq, FAR void *context)
{
register FAR struct enc28j60_drver_s *priv = &g_enc28j60[0];
/* Disable Ethernet interrupts */
/* Get and clear interrupt status bits */
/* Handle interrupts according to status bit settings */
/* Check if we received an incoming packet, if so, call enc28j60_receive() */
enc28j60_receive(priv);
/* Check is a packet transmission just completed. If so, call enc28j60_txdone */
enc28j60_txdone(priv);
/* Enable Ethernet interrupts (perhaps excluding the TX done interrupt if
* there are no pending transmissions.
*/
return OK;
}
/****************************************************************************
* Function: enc28j60_txtimeout
*
* Description:
* Our TX watchdog timed out. Called from the timer interrupt handler.
* The last TX never completed. Reset the hardware and start again.
*
* Parameters:
* argc - The number of available arguments
* arg - The first argument
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
static void enc28j60_txtimeout(int argc, uint32_t arg, ...)
{
FAR struct enc28j60_drver_s *priv = (FAR struct enc28j60_drver_s *)arg;
/* Increment statistics and dump debug info */
/* Then reset the hardware */
/* Then poll uIP for new XMIT data */
(void)uip_poll(&priv->dev, enc28j60_uiptxpoll);
}
/****************************************************************************
* Function: enc28j60_polltimer
*
* Description:
* Periodic timer handler. Called from the timer interrupt handler.
*
* Parameters:
* argc - The number of available arguments
* arg - The first argument
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
static void enc28j60_polltimer(int argc, uint32_t arg, ...)
{
FAR struct enc28j60_drver_s *priv = (FAR struct enc28j60_drver_s *)arg;
/* Check if there is room in the send another TXr packet. */
/* If so, update TCP timing states and poll uIP for new XMIT data */
(void)uip_timer(&priv->dev, enc28j60_uiptxpoll, ENC28J60_POLLHSEC);
/* Setup the watchdog poll timer again */
(void)wd_start(priv->txpoll, ENC28J60_WDDELAY, enc28j60_polltimer, 1, arg);
}
/****************************************************************************
* Function: enc28j60_ifup
*
* Description:
* NuttX Callback: Bring up the Ethernet interface when an IP address is
* provided
*
* Parameters:
* dev - Reference to the NuttX driver state structure
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
static int enc28j60_ifup(struct uip_driver_s *dev)
{
FAR struct enc28j60_drver_s *priv = (FAR struct enc28j60_drver_s *)dev->d_private;
ndbg("Bringing up: %d.%d.%d.%d\n",
dev->d_ipaddr & 0xff, (dev->d_ipaddr >> 8) & 0xff,
(dev->d_ipaddr >> 16) & 0xff, dev->d_ipaddr >> 24 );
/* Initilize Ethernet interface */
/* Set and activate a timer process */
(void)wd_start(priv->txpoll, ENC28J60_WDDELAY, enc28j60_polltimer, 1, (uint32_t)priv);
/* Enable the Ethernet interrupt */
priv->bifup = true;
up_enable_irq(CONFIG_ENC28J60_IRQ);
return OK;
}
/****************************************************************************
* Function: enc28j60_ifdown
*
* Description:
* NuttX Callback: Stop the interface.
*
* Parameters:
* dev - Reference to the NuttX driver state structure
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
static int enc28j60_ifdown(struct uip_driver_s *dev)
{
FAR struct enc28j60_drver_s *priv = (FAR struct enc28j60_drver_s *)dev->d_private;
irqstate_t flags;
/* Disable the Ethernet interrupt */
flags = irqsave();
up_disable_irq(CONFIG_ENC28J60_IRQ);
/* Cancel the TX poll timer and TX timeout timers */
wd_cancel(priv->txpoll);
wd_cancel(priv->txtimeout);
/* Reset the device */
priv->bifup = false;
irqrestore(flags);
return OK;
}
/****************************************************************************
* Function: enc28j60_txavail
*
* Description:
* Driver callback invoked when new TX data is available. This is a
* stimulus perform an out-of-cycle poll and, thereby, reduce the TX
* latency.
*
* Parameters:
* dev - Reference to the NuttX driver state structure
*
* Returned Value:
* None
*
* Assumptions:
* Called in normal user mode
*
****************************************************************************/
static int enc28j60_txavail(struct uip_driver_s *dev)
{
FAR struct enc28j60_drver_s *priv = (FAR struct enc28j60_drver_s *)dev->d_private;
irqstate_t flags;
flags = irqsave();
/* Ignore the notification if the interface is not yet up */
if (priv->bifup)
{
/* Check if there is room in the hardware to hold another outgoing packet. */
/* If so, then poll uIP for new XMIT data */
(void)uip_poll(&priv->dev, enc28j60_uiptxpoll);
}
irqrestore(flags);
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: enc28j60_initialize
*
* Description:
* Initialize the Ethernet driver
*
* Parameters:
* None
*
* Returned Value:
* OK on success; Negated errno on failure.
*
* Assumptions:
*
****************************************************************************/
/* Initialize the Ethernet controller and driver */
int enc28j60_initialize(FAR struct spi_dev_s *spi)
{
/* Initialize and configure the ENC28J60 */
/* Initialize the driver structure */
memset(g_enc28j60, 0, CONFIG_ENC28J60_NINTERFACES*sizeof(struct enc28j60_driver_s));
g_enc28j60[0].dev.d_ifup = enc28j60_ifup; /* I/F down callback */
g_enc28j60[0].dev.d_ifdown = enc28j60_ifdown; /* I/F up (new IP address) callback */
g_enc28j60[0].dev.d_txavail = enc28j60_txavail; /* New TX data callback */
g_enc28j60[0].dev.d_private = (void*)g_enc28j60; /* Used to recover private state from dev */
/* Create a watchdog for timing polling for and timing of transmisstions */
g_enc28j60[0].txpoll = wd_create(); /* Create periodic poll timer */
g_enc28j60[0].txtimeout = wd_create(); /* Create TX timeout timer */
g_enc28j60[0].spi = spi; /* Save the SPI instance */
/* Attach the IRQ to the driver */
if (irq_attach(CONFIG_ENC28J60_IRQ, enc28j60_interrupt))
{
/* We could not attach the ISR to the interrupt */
return -EAGAIN;
}
/* Read the MAC address from the hardware into g_enc28j60[0].dev.d_mac.ether_addr_octet */
/* Register the device with the OS so that socket IOCTLs can be performed */
(void)netdev_register(&g_enc28j60[0].dev);
return OK;
}
#endif /* CONFIG_NET && CONFIG_ENC28J60_NET */