/* SPDX-License-Identifier: GPL-2.0 */
#ifndef B43legacy_PIO_H_
#define B43legacy_PIO_H_

#include "b43legacy.h"

#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/skbuff.h>


#define B43legacy_PIO_TXCTL             0x00
#define B43legacy_PIO_TXDATA            0x02
#define B43legacy_PIO_TXQBUFSIZE        0x04
#define B43legacy_PIO_RXCTL             0x08
#define B43legacy_PIO_RXDATA            0x0A

#define B43legacy_PIO_TXCTL_WRITELO     (1 << 0)
#define B43legacy_PIO_TXCTL_WRITEHI     (1 << 1)
#define B43legacy_PIO_TXCTL_COMPLETE    (1 << 2)
#define B43legacy_PIO_TXCTL_INIT        (1 << 3)
#define B43legacy_PIO_TXCTL_SUSPEND     (1 << 7)

#define B43legacy_PIO_RXCTL_DATAAVAILABLE       (1 << 0)
#define B43legacy_PIO_RXCTL_READY               (1 << 1)

/* PIO constants */
#define B43legacy_PIO_MAXTXDEVQPACKETS  31
#define B43legacy_PIO_TXQADJUST         80

/* PIO tuning knobs */
#define B43legacy_PIO_MAXTXPACKETS      256



#ifdef CONFIG_B43LEGACY_PIO


struct b43legacy_pioqueue;
struct b43legacy_xmitstatus;

struct b43legacy_pio_txpacket {
        struct b43legacy_pioqueue *queue;
        struct sk_buff *skb;
        struct list_head list;
};

#define pio_txpacket_getindex(packet) ((int)((packet) - \
                              (packet)->queue->tx_packets_cache))

struct b43legacy_pioqueue {
        struct b43legacy_wldev *dev;
        u16 mmio_base;

        bool tx_suspended;
        bool tx_frozen;
        bool need_workarounds; /* Workarounds needed for core.rev < 3 */

        /* Adjusted size of the device internal TX buffer. */
        u16 tx_devq_size;
        /* Used octets of the device internal TX buffer. */
        u16 tx_devq_used;
        /* Used packet slots in the device internal TX buffer. */
        u8 tx_devq_packets;
        /* Packets from the txfree list can
         * be taken on incoming TX requests.
         */
        struct list_head txfree;
        unsigned int nr_txfree;
        /* Packets on the txqueue are queued,
         * but not completely written to the chip, yet.
         */
        struct list_head txqueue;
        /* Packets on the txrunning queue are completely
         * posted to the device. We are waiting for the txstatus.
         */
        struct list_head txrunning;
        struct tasklet_struct txtask;
        struct b43legacy_pio_txpacket
                         tx_packets_cache[B43legacy_PIO_MAXTXPACKETS];
};

static inline
u16 b43legacy_pio_read(struct b43legacy_pioqueue *queue,
                     u16 offset)
{
        return b43legacy_read16(queue->dev, queue->mmio_base + offset);
}

static inline
void b43legacy_pio_write(struct b43legacy_pioqueue *queue,
                       u16 offset, u16 value)
{
        b43legacy_write16(queue->dev, queue->mmio_base + offset, value);
}


int b43legacy_pio_init(struct b43legacy_wldev *dev);
void b43legacy_pio_free(struct b43legacy_wldev *dev);

int b43legacy_pio_tx(struct b43legacy_wldev *dev,
                   struct sk_buff *skb);
void b43legacy_pio_handle_txstatus(struct b43legacy_wldev *dev,
                                 const struct b43legacy_txstatus *status);
void b43legacy_pio_rx(struct b43legacy_pioqueue *queue);

/* Suspend TX queue in hardware. */
void b43legacy_pio_tx_suspend(struct b43legacy_pioqueue *queue);
void b43legacy_pio_tx_resume(struct b43legacy_pioqueue *queue);
/* Suspend (freeze) the TX tasklet (software level). */
void b43legacy_pio_freeze_txqueues(struct b43legacy_wldev *dev);
void b43legacy_pio_thaw_txqueues(struct b43legacy_wldev *dev);

#else /* CONFIG_B43LEGACY_PIO */

static inline
int b43legacy_pio_init(struct b43legacy_wldev *dev)
{
        return 0;
}
static inline
void b43legacy_pio_free(struct b43legacy_wldev *dev)
{
}
static inline
int b43legacy_pio_tx(struct b43legacy_wldev *dev,
                   struct sk_buff *skb)
{
        return 0;
}
static inline
void b43legacy_pio_handle_txstatus(struct b43legacy_wldev *dev,
                                 const struct b43legacy_txstatus *status)
{
}
static inline
void b43legacy_pio_rx(struct b43legacy_pioqueue *queue)
{
}
static inline
void b43legacy_pio_tx_suspend(struct b43legacy_pioqueue *queue)
{
}
static inline
void b43legacy_pio_tx_resume(struct b43legacy_pioqueue *queue)
{
}
static inline
void b43legacy_pio_freeze_txqueues(struct b43legacy_wldev *dev)
{
}
static inline
void b43legacy_pio_thaw_txqueues(struct b43legacy_wldev *dev)
{
}

#endif /* CONFIG_B43LEGACY_PIO */
#endif /* B43legacy_PIO_H_ */