path: root/drivers/net/ks8851.c

/* drivers/net/ks8651.c
 *
 * Copyright 2009 Simtec Electronics
 *	http://www.simtec.co.uk/
 *	Ben Dooks <ben@simtec.co.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#define DEBUG

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/cache.h>
#include <linux/crc32.h>
#include <linux/mii.h>

#include <linux/spi/spi.h>

#include "ks8851.h"

/**
 * struct ks8851_rxctrl - KS8851 driver rx control
 * @mchash: Multicast hash-table data.
 * @rxcr1: KS_RXCR1 register setting
 * @rxcr2: KS_RXCR2 register setting
 *
 * Representation of the settings needs to control the receive filtering
 * such as the multicast hash-filter and the receive register settings. This
 * is used to make the job of working out if the receive settings change and
 * then issuing the new settings to the worker that will send the necessary
 * commands.
 */
struct ks8851_rxctrl {
	u16	mchash[4];
	u16	rxcr1;
	u16	rxcr2;
};

/**
 * union ks8851_tx_hdr - tx header data
 * @txb: The header as bytes
 * @txw: The header as 16bit, little-endian words
 *
 * A dual representation of the tx header data to allow
 * access to individual bytes, and to allow 16bit accesses
 * with 16bit alignment.
 */
union ks8851_tx_hdr {
	u8	txb[6];
	__le16	txw[3];
};

/**
 * struct ks8851_net - KS8851 driver private data
 * @netdev: The network device we're bound to
 * @spidev: The spi device we're bound to.
 * @lock: Lock to ensure that the device is not accessed when busy.
 * @statelock: Lock on this structure for tx list.
 * @mii: The MII state information for the mii calls.
 * @rxctrl: RX settings for @rxctrl_work.
 * @tx_work: Work queue for tx packets
 * @irq_work: Work queue for servicing interrupts
 * @rxctrl_work: Work queue for updating RX mode and multicast lists
 * @txq: Queue of packets for transmission.
 * @spi_msg1: pre-setup SPI transfer with one message, @spi_xfer1.
 * @spi_msg2: pre-setup SPI transfer with two messages, @spi_xfer2.
 * @txh: Space for generating packet TX header in DMA-able data
 * @rxd: Space for receiving SPI data, in DMA-able space.
 * @txd: Space for transmitting SPI data, in DMA-able space.
 * @msg_enable: The message flags controlling driver output (see ethtool).
 * @fid: Incrementing frame id tag.
 * @rc_ier: Cached copy of KS_IER.
 * @rc_rxqcr: Cached copy of KS_RXQCR.
 *
 * The @lock ensures that the chip is protected when certain operations are
 * in progress. When the read or write packet transfer is in progress, most
 * of the chip registers are not ccessible until the transfer is finished and
 * the DMA has been de-asserted.
 *
 * The @statelock is used to protect information in the structure which may
 * need to be accessed via several sources, such as the network driver layer
 * or one of the work queues.
 *
 * We align the buffers we may use for rx/tx to ensure that if the SPI driver
 * wants to DMA map them, it will not have any problems with data the driver
 * modifies.
 */
struct ks8851_net {
	struct net_device	*netdev;
	struct spi_device	*spidev;
	struct mutex		lock;
	spinlock_t		statelock;

	union ks8851_tx_hdr	txh ____cacheline_aligned;
	u8			rxd[8];
	u8			txd[8];

	u32			msg_enable ____cacheline_aligned;
	u16			tx_space;
	u8			fid;

	u16			rc_ier;
	u16			rc_rxqcr;

	struct mii_if_info	mii;
	struct ks8851_rxctrl	rxctrl;

	struct work_struct	tx_work;
	struct work_struct	irq_work;
	struct work_struct	rxctrl_work;

	struct sk_buff_head	txq;

	struct spi_message	spi_msg1;
	struct spi_message	spi_msg2;
	struct spi_transfer	spi_xfer1;
	struct spi_transfer	spi_xfer2[2];
};

static int msg_enable;

#define ks_info(_ks, _msg...) dev_info(&(_ks)->spidev->dev, _msg)
#define ks_warn(_ks, _msg...) dev_warn(&(_ks)->spidev->dev, _msg)
#define ks_dbg(_ks, _msg...) dev_dbg(&(_ks)->spidev->dev, _msg)
#define ks_err(_ks, _msg...) dev_err(&(_ks)->spidev->dev, _msg)