/* SPDX-License-Identifier: GPL-2.0 */

/***************************************************************************
 *    copyright            : (C) 2002 by Frank Mori Hess
 ***************************************************************************/

#ifndef _NEC7210_H
#define _NEC7210_H

#include "gpib_state_machines.h"
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/interrupt.h>

#include "gpib_types.h"
#include "nec7210_registers.h"

/* struct used to provide variables local to a nec7210 chip */
struct nec7210_priv {
#ifdef CONFIG_HAS_IOPORT
        u32 iobase;
#endif
        void __iomem *mmiobase;
        unsigned int offset;            // offset between successive nec7210 io addresses
        unsigned int dma_channel;
        u8 *dma_buffer;
        unsigned int dma_buffer_length; // length of dma buffer
        dma_addr_t dma_buffer_addr;     // bus address of board->buffer for use with dma
        // software copy of bits written to registers
        u8 reg_bits[8];
        u8 auxa_bits;                   // bits written to auxiliary register A
        u8 auxb_bits;                   // bits written to auxiliary register B
        // used to keep track of board's state, bit definitions given below
        unsigned long state;
        // lock for chips that extend the nec7210 registers by paging in alternate regs
        spinlock_t register_page_lock;
        // wrappers for outb, inb, readb, or writeb
        u8 (*read_byte)(struct nec7210_priv *priv, unsigned int register_number);
        void (*write_byte)(struct nec7210_priv *priv, u8 byte, unsigned int register_number);
        enum nec7210_chipset type;
        enum talker_function_state talker_state;
        enum listener_function_state listener_state;
        void *private;
        unsigned srq_pending : 1;
};

static inline void init_nec7210_private(struct nec7210_priv *priv)
{
        memset(priv, 0, sizeof(struct nec7210_priv));
        spin_lock_init(&priv->register_page_lock);
}

// slightly shorter way to access read_byte and write_byte
static inline u8 read_byte(struct nec7210_priv *priv, unsigned int register_number)
{
        return priv->read_byte(priv, register_number);
}

static inline void write_byte(struct nec7210_priv *priv, u8 byte, unsigned int register_number)
{
        priv->write_byte(priv, byte, register_number);
}

// struct nec7210_priv.state bit numbers
enum {
        PIO_IN_PROGRESS_BN,             // pio transfer in progress
        DMA_READ_IN_PROGRESS_BN,        // dma read transfer in progress
        DMA_WRITE_IN_PROGRESS_BN,       // dma write transfer in progress
        READ_READY_BN,                  // board has data byte available to read
        WRITE_READY_BN,                 // board is ready to send a data byte
        COMMAND_READY_BN,               // board is ready to send a command byte
        RECEIVED_END_BN,                // received END
        BUS_ERROR_BN,                   // output error has occurred
        RFD_HOLDOFF_BN,                 // rfd holdoff in effect
        DEV_CLEAR_BN,                   // device clear received
        ADR_CHANGE_BN,                  // address state change occurred
};

// interface functions
int nec7210_read(struct gpib_board *board, struct nec7210_priv *priv, u8 *buffer,
                 size_t length, int *end, size_t *bytes_read);
int nec7210_write(struct gpib_board *board, struct nec7210_priv *priv, u8 *buffer,
                  size_t length, int send_eoi, size_t *bytes_written);
int nec7210_command(struct gpib_board *board, struct nec7210_priv *priv, u8 *buffer,
                    size_t length, size_t *bytes_written);
int nec7210_take_control(struct gpib_board *board, struct nec7210_priv *priv, int syncronous);
int nec7210_go_to_standby(struct gpib_board *board, struct nec7210_priv *priv);
int nec7210_request_system_control(struct gpib_board *board,
                                   struct nec7210_priv *priv, int request_control);
void nec7210_interface_clear(struct gpib_board *board, struct nec7210_priv *priv, int assert);
void nec7210_remote_enable(struct gpib_board *board, struct nec7210_priv *priv, int enable);
int nec7210_enable_eos(struct gpib_board *board, struct nec7210_priv *priv, u8 eos_bytes,
                       int compare_8_bits);
void nec7210_disable_eos(struct gpib_board *board, struct nec7210_priv *priv);
unsigned int nec7210_update_status(struct gpib_board *board, struct nec7210_priv *priv,
                                   unsigned int clear_mask);
unsigned int nec7210_update_status_nolock(struct gpib_board *board, struct nec7210_priv *priv);
int nec7210_primary_address(const struct gpib_board *board,
                            struct nec7210_priv *priv, unsigned int address);
int nec7210_secondary_address(const struct gpib_board *board, struct nec7210_priv *priv,
                              unsigned int address, int enable);
int nec7210_parallel_poll(struct gpib_board *board, struct nec7210_priv *priv, u8 *result);
void nec7210_serial_poll_response(struct gpib_board *board,
                                  struct nec7210_priv *priv, u8 status);
void nec7210_parallel_poll_configure(struct gpib_board *board,
                                     struct nec7210_priv *priv, unsigned int configuration);
void nec7210_parallel_poll_response(struct gpib_board *board,
                                    struct nec7210_priv *priv, int ist);
u8 nec7210_serial_poll_status(struct gpib_board *board, struct nec7210_priv *priv);
int nec7210_t1_delay(struct gpib_board *board,
                     struct nec7210_priv *priv, unsigned int nano_sec);
void nec7210_return_to_local(const struct gpib_board *board, struct nec7210_priv *priv);

// utility functions
void nec7210_board_reset(struct nec7210_priv *priv, const struct gpib_board *board);
void nec7210_board_online(struct nec7210_priv *priv, const struct gpib_board *board);
unsigned int nec7210_set_reg_bits(struct nec7210_priv *priv, unsigned int reg,
                                  unsigned int mask, unsigned int bits);
void nec7210_set_handshake_mode(struct gpib_board *board, struct nec7210_priv *priv, int mode);
void nec7210_release_rfd_holdoff(struct gpib_board *board, struct nec7210_priv *priv);
u8 nec7210_read_data_in(struct gpib_board *board, struct nec7210_priv *priv, int *end);

// wrappers for io functions
u8 nec7210_ioport_read_byte(struct nec7210_priv *priv, unsigned int register_num);
void nec7210_ioport_write_byte(struct nec7210_priv *priv, u8 data, unsigned int register_num);
u8 nec7210_iomem_read_byte(struct nec7210_priv *priv, unsigned int register_num);
void nec7210_iomem_write_byte(struct nec7210_priv *priv, u8 data, unsigned int register_num);
u8 nec7210_locking_ioport_read_byte(struct nec7210_priv *priv, unsigned int register_num);
void nec7210_locking_ioport_write_byte(struct nec7210_priv *priv, u8 data,
                                       unsigned int register_num);
u8 nec7210_locking_iomem_read_byte(struct nec7210_priv *priv, unsigned int register_num);
void nec7210_locking_iomem_write_byte(struct nec7210_priv *priv, u8 data,
                                      unsigned int register_num);

// interrupt service routine
irqreturn_t nec7210_interrupt(struct gpib_board *board, struct nec7210_priv *priv);
irqreturn_t nec7210_interrupt_have_status(struct gpib_board *board,
                                          struct nec7210_priv *priv, int status1, int status2);

#endif  //_NEC7210_H