path: root/drivers/net/ethernet/davicom/dm9051.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2022 Davicom Semiconductor,Inc.
 * Davicom DM9051 SPI Fast Ethernet Linux driver
 */

#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/irq.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/phy.h>
#include <linux/regmap.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/spi/spi.h>
#include <linux/types.h>

#include "dm9051.h"

#define DRVNAME_9051	"dm9051"

/**
 * struct rx_ctl_mach - rx activities record
 * @status_err_counter: rx status error counter
 * @large_err_counter: rx get large packet length error counter
 * @rx_err_counter: receive packet error counter
 * @tx_err_counter: transmit packet error counter
 * @fifo_rst_counter: reset operation counter
 *
 * To keep track for the driver operation statistics
 */
struct rx_ctl_mach {
	u16				status_err_counter;
	u16				large_err_counter;
	u16				rx_err_counter;
	u16				tx_err_counter;
	u16				fifo_rst_counter;
};

/**
 * struct dm9051_rxctrl - dm9051 driver rx control
 * @hash_table: Multicast hash-table data
 * @rcr_all: KS_RXCR1 register setting
 *
 * The settings needs to control the receive filtering
 * such as the multicast hash-filter and the receive register settings
 */
struct dm9051_rxctrl {
	u16				hash_table[4];
	u8				rcr_all;
};

/**
 * struct dm9051_rxhdr - rx packet data header
 * @headbyte: lead byte equal to 0x01 notifies a valid packet
 * @status: status bits for the received packet
 * @rxlen: packet length
 *
 * The Rx packed, entered into the FIFO memory, start with these
 * four bytes which is the Rx header, followed by the ethernet
 * packet data and ends with an appended 4-byte CRC data.
 * Both Rx packet and CRC data are for check purpose and finally
 * are dropped by this driver
 */
struct dm9051_rxhdr {
	u8				headbyte;
	u8				status;
	__le16				rxlen;
};

/**
 * struct board_info - maintain the saved data
 * @spidev: spi device structure
 * @ndev: net device structure
 * @mdiobus: mii bus structure
 * @phydev: phy device structure
 * @txq: tx queue structure
 * @regmap_dm: regmap for register read/write
 * @regmap_dmbulk: extra regmap for bulk read/write
 * @rxctrl_work: Work queue for updating RX mode and multicast lists
 * @tx_work: Work queue for tx packets
 * @pause: ethtool pause parameter structure
 * @spi_lockm: between threads lock structure
 * @reg_mutex: regmap access lock structure
 * @bc: rx control statistics structure
 * @rxhdr: rx header structure
 * @rctl: rx control setting structure
 * @msg_enable: message level value
 * @imr_all: to store operating imr value for register DM9051_IMR
 * @lcr_all: to store operating rcr value for register DM9051_LMCR
 *
 * The saved data variables, keep up to date for retrieval back to use
 */
struct board_info {
	u32				msg_enable;
	struct spi_device		*spidev;
	struct net_device		*ndev;
	struct mii_bus			*mdiobus;
	struct phy_device		*phydev;
	struct sk_buff_head		txq;
	struct regmap			*regmap_dm;
	struct regmap			*regmap_dmbulk;
	struct work_struct		rxctrl_work;
	struct work_struct		tx_work;
	struct ethtool_pauseparam	pause;
	struct mutex			spi_lockm;
	struct mutex			reg_mutex;
	struct rx_ctl_mach		bc;
	struct dm9051_rxhdr		rxhdr;
	struct dm9051_rxctrl		rctl;
	u8				imr_all;
	u8				lcr_all;
};

static int dm9051_set_reg(struct board_info *db, unsigned int reg, unsigned int val)
{
	int ret;

	ret = regmap_write(db->regmap_dm, reg, val);
	if (ret < 0)
		netif_err(db, drv, db->ndev, "%s: error %d set reg %02x\n",
			  __func__, ret, reg);
	return ret;
}

static int dm9051_update_bits(struct board_info *db, unsigned int reg, unsigned int mask,
			      unsigned int val)
{
	int ret;

	ret = regmap_update_bits(db->regmap_dm, reg, mask, val);
	if (ret < 0)
		netif_err(db, drv, db->ndev, "%s: error %d update bits reg %02x\n",
			  __func__, ret, reg);
	return ret;
}

/* skb buffer exhausted, just discard the received data
 */
static int dm9051_dumpblk(struct board_info *db, u8 reg, size_t count)
{
	struct net_device *ndev = db->ndev;
	unsigned int rb<