/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * module/mite.h
 * Hardware driver for NI Mite PCI interface chip
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 1999 David A. Schleef <ds@schleef.org>
 */

#ifndef _MITE_H_
#define _MITE_H_

#include <linux/spinlock.h>

#define MAX_MITE_DMA_CHANNELS 8

struct comedi_device;
struct comedi_subdevice;
struct device;
struct pci_dev;

struct mite_dma_desc {
        __le32 count;
        __le32 addr;
        __le32 next;
        u32 dar;
};

struct mite_ring {
        struct device *hw_dev;
        unsigned int n_links;
        struct mite_dma_desc *descs;
        dma_addr_t dma_addr;
};

struct mite_channel {
        struct mite *mite;
        unsigned int channel;
        int dir;
        int done;
        struct mite_ring *ring;
};

struct mite {
        struct pci_dev *pcidev;
        void __iomem *mmio;
        struct mite_channel channels[MAX_MITE_DMA_CHANNELS];
        int num_channels;
        unsigned int fifo_size;
        /* protects mite_channel from being released by the driver */
        spinlock_t lock;
};

u32 mite_bytes_in_transit(struct mite_channel *mite_chan);

void mite_sync_dma(struct mite_channel *mite_chan, struct comedi_subdevice *s);
void mite_ack_linkc(struct mite_channel *mite_chan, struct comedi_subdevice *s,
                    bool sync);
int mite_done(struct mite_channel *mite_chan);

void mite_dma_arm(struct mite_channel *mite_chan);
void mite_dma_disarm(struct mite_channel *mite_chan);

void mite_prep_dma(struct mite_channel *mite_chan,
                   unsigned int num_device_bits, unsigned int num_memory_bits);

struct mite_channel *mite_request_channel_in_range(struct mite *mite,
                                                   struct mite_ring *ring,
                                                   unsigned int min_channel,
                                                   unsigned int max_channel);
struct mite_channel *mite_request_channel(struct mite *mite,
                                          struct mite_ring *ring);
void mite_release_channel(struct mite_channel *mite_chan);

int mite_init_ring_descriptors(struct mite_ring *ring,
                               struct comedi_subdevice *s, unsigned int nbytes);
int mite_buf_change(struct mite_ring *ring, struct comedi_subdevice *s);

struct mite_ring *mite_alloc_ring(struct mite *mite);
void mite_free_ring(struct mite_ring *ring);

struct mite *mite_attach(struct comedi_device *dev, bool use_win1);
void mite_detach(struct mite *mite);

/*
 * Mite registers (used outside of the mite driver)
 */
#define MITE_IODWBSR            0xc0    /* IO Device Window Base Size */
#define MITE_IODWBSR_1          0xc4    /* IO Device Window1 Base Size */
#define WENAB                   BIT(7)  /* window enable */
#define MITE_IODWCR_1           0xf4

#endif