// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for Sound Core PDAudioCF soundcard
 *
 * Copyright (c) 2003 by Jaroslav Kysela <perex@perex.cz>
 */

#include <sound/core.h>
#include "pdaudiocf.h"
#include <sound/initval.h>
#include <asm/irq_regs.h>

/*
 *
 */
irqreturn_t pdacf_interrupt(int irq, void *dev)
{
        struct snd_pdacf *chip = dev;
        unsigned short stat;
        bool wake_thread = false;

        if ((chip->chip_status & (PDAUDIOCF_STAT_IS_STALE|
                                  PDAUDIOCF_STAT_IS_CONFIGURED|
                                  PDAUDIOCF_STAT_IS_SUSPENDED)) != PDAUDIOCF_STAT_IS_CONFIGURED)
                return IRQ_HANDLED;     /* IRQ_NONE here? */

        stat = inw(chip->port + PDAUDIOCF_REG_ISR);
        if (stat & (PDAUDIOCF_IRQLVL|PDAUDIOCF_IRQOVR)) {
                if (stat & PDAUDIOCF_IRQOVR)    /* should never happen */
                        dev_err(chip->card->dev, "PDAUDIOCF SRAM buffer overrun detected!\n");
                if (chip->pcm_substream)
                        wake_thread = true;
                if (!(stat & PDAUDIOCF_IRQAKM))
                        stat |= PDAUDIOCF_IRQAKM;       /* check rate */
        }
        if (get_irq_regs() != NULL)
                snd_ak4117_check_rate_and_errors(chip->ak4117, 0);
        return wake_thread ? IRQ_WAKE_THREAD : IRQ_HANDLED;
}

static inline void pdacf_transfer_mono16(u16 *dst, u16 xor, unsigned int size, unsigned long rdp_port)
{
        while (size-- > 0) {
                *dst++ = inw(rdp_port) ^ xor;
                inw(rdp_port);
        }
}

static inline void pdacf_transfer_mono32(u32 *dst, u32 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                inw(rdp_port);
                *dst++ = ((((u32)val2 & 0xff) << 24) | ((u32)val1 << 8)) ^ xor;
        }
}

static inline void pdacf_transfer_stereo16(u16 *dst, u16 xor, unsigned int size, unsigned long rdp_port)
{
        while (size-- > 0) {
                *dst++ = inw(rdp_port) ^ xor;
                *dst++ = inw(rdp_port) ^ xor;
        }
}

static inline void pdacf_transfer_stereo32(u32 *dst, u32 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2, val3;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                val3 = inw(rdp_port);
                *dst++ = ((((u32)val2 & 0xff) << 24) | ((u32)val1 << 8)) ^ xor;
                *dst++ = (((u32)val3 << 16) | (val2 & 0xff00)) ^ xor;
        }
}

static inline void pdacf_transfer_mono16sw(u16 *dst, u16 xor, unsigned int size, unsigned long rdp_port)
{
        while (size-- > 0) {
                *dst++ = swab16(inw(rdp_port) ^ xor);
                inw(rdp_port);
        }
}

static inline void pdacf_transfer_mono32sw(u32 *dst, u32 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                inw(rdp_port);
                *dst++ = swab32((((val2 & 0xff) << 24) | ((u32)val1 << 8)) ^ xor);
        }
}

static inline void pdacf_transfer_stereo16sw(u16 *dst, u16 xor, unsigned int size, unsigned long rdp_port)
{
        while (size-- > 0) {
                *dst++ = swab16(inw(rdp_port) ^ xor);
                *dst++ = swab16(inw(rdp_port) ^ xor);
        }
}

static inline void pdacf_transfer_stereo32sw(u32 *dst, u32 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2, val3;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                val3 = inw(rdp_port);
                *dst++ = swab32((((val2 & 0xff) << 24) | ((u32)val1 << 8)) ^ xor);
                *dst++ = swab32((((u32)val3 << 16) | (val2 & 0xff00)) ^ xor);
        }
}

static inline void pdacf_transfer_mono24le(u8 *dst, u16 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2;
        register u32 xval1;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                inw(rdp_port);
                xval1 = (((val2 & 0xff) << 8) | (val1 << 16)) ^ xor;
                *dst++ = (u8)(xval1 >> 8);
                *dst++ = (u8)(xval1 >> 16);
                *dst++ = (u8)(xval1 >> 24);
        }
}

static inline void pdacf_transfer_mono24be(u8 *dst, u16 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2;
        register u32 xval1;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                inw(rdp_port);
                xval1 = (((val2 & 0xff) << 8) | (val1 << 16)) ^ xor;
                *dst++ = (u8)(xval1 >> 24);
                *dst++ = (u8)(xval1 >> 16);
                *dst++ = (u8)(xval1 >> 8);
        }
}

static inline void pdacf_transfer_stereo24le(u8 *dst, u32 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2, val3;
        register u32 xval1, xval2;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                val3 = inw(rdp_port);
                xval1 = ((((u32)val2 & 0xff) << 24) | ((u32)val1 << 8)) ^ xor;
                xval2 = (((u32)val3 << 16) | (val2 & 0xff00)) ^ xor;
                *dst++ = (u8)(xval1 >> 8);
                *dst++ = (u8)(xval1 >> 16);
                *dst++ = (u8)(xval1 >> 24);
                *dst++ = (u8)(xval2 >> 8);
                *dst++ = (u8)(xval2 >> 16);
                *dst++ = (u8)(xval2 >> 24);
        }
}

static inline void pdacf_transfer_stereo24be(u8 *dst, u32 xor, unsigned int size, unsigned long rdp_port)
{
        register u16 val1, val2, val3;
        register u32 xval1, xval2;

        while (size-- > 0) {
                val1 = inw(rdp_port);
                val2 = inw(rdp_port);
                val3 = inw(rdp_port);
                xval1 = ((((u32)val2 & 0xff) << 24) | ((u32)val1 << 8)) ^ xor;
                xval2 = (((u32)val3 << 16) | (val2 & 0xff00)) ^ xor;
                *dst++ = (u8)(xval1 >> 24);
                *dst++ = (u8)(xval1 >> 16);
                *dst++ = (u8)(xval1 >> 8);
                *dst++ = (u8)(xval2 >> 24);
                *dst++ = (u8)(xval2 >> 16);
                *dst++ = (u8)(xval2 >> 8);
        }
}

static void pdacf_transfer(struct snd_pdacf *chip, unsigned int size, unsigned int off)
{
        unsigned long rdp_port = chip->port + PDAUDIOCF_REG_MD;
        unsigned int xor = chip->pcm_xor;

        if (chip->pcm_sample == 3) {
                if (chip->pcm_little) {
                        if (chip->pcm_channels == 1) {
                                pdacf_transfer_mono24le((char *)chip->pcm_area + (off * 3), xor, size, rdp_port);
                        } else {
                                pdacf_transfer_stereo24le((char *)chip->pcm_area + (off * 6), xor, size, rdp_port);
                        }
                } else {
                        if (chip->pcm_channels == 1) {
                                pdacf_transfer_mono24be((char *)chip->pcm_area + (off * 3), xor, size, rdp_port);
                        } else {
                                pdacf_transfer_stereo24be((char *)chip->pcm_area + (off * 6), xor, size, rdp_port);
                        }                       
                }
                return;
        }
        if (chip->pcm_swab == 0) {
                if (chip->pcm_channels == 1) {
                        if (chip->pcm_frame == 2) {
                                pdacf_transfer_mono16((u16 *)chip->pcm_area + off, xor, size, rdp_port);
                        } else {
                                pdacf_transfer_mono32((u32 *)chip->pcm_area + off, xor, size, rdp_port);
                        }
                } else {
                        if (chip->pcm_frame == 2) {
                                pdacf_transfer_stereo16((u16 *)chip->pcm_area + (off * 2), xor, size, rdp_port);
                        } else {
                                pdacf_transfer_stereo32((u32 *)chip->pcm_area + (off * 2), xor, size, rdp_port);
                        }
                }
        } else {
                if (chip->pcm_channels == 1) {
                        if (chip->pcm_frame == 2) {
                                pdacf_transfer_mono16sw((u16 *)chip->pcm_area + off, xor, size, rdp_port);
                        } else {
                                pdacf_transfer_mono32sw((u32 *)chip->pcm_area + off, xor, size, rdp_port);
                        }
                } else {
                        if (chip->pcm_frame == 2) {
                                pdacf_transfer_stereo16sw((u16 *)chip->pcm_area + (off * 2), xor, size, rdp_port);
                        } else {
                                pdacf_transfer_stereo32sw((u32 *)chip->pcm_area + (off * 2), xor, size, rdp_port);
                        }
                }
        }
}

irqreturn_t pdacf_threaded_irq(int irq, void *dev)
{
        struct snd_pdacf *chip = dev;
        int size, off, cont, rdp, wdp;

        if ((chip->chip_status & (PDAUDIOCF_STAT_IS_STALE|PDAUDIOCF_STAT_IS_CONFIGURED)) != PDAUDIOCF_STAT_IS_CONFIGURED)
                return IRQ_HANDLED;
        
        if (chip->pcm_substream == NULL || chip->pcm_substream->runtime == NULL || !snd_pcm_running(chip->pcm_substream))
                return IRQ_HANDLED;

        rdp = inw(chip->port + PDAUDIOCF_REG_RDP);
        wdp = inw(chip->port + PDAUDIOCF_REG_WDP);
        size = wdp - rdp;
        if (size < 0)
                size += 0x10000;
        if (size == 0)
                size = 0x10000;
        size /= chip->pcm_frame;
        if (size > 64)
                size -= 32;

#if 0
        chip->pcm_hwptr += size;
        chip->pcm_hwptr %= chip->pcm_size;
        chip->pcm_tdone += size;
        if (chip->pcm_frame == 2) {
                unsigned long rdp_port = chip->port + PDAUDIOCF_REG_MD;
                while (size-- > 0) {
                        inw(rdp_port);
                        inw(rdp_port);
                }
        } else {
                unsigned long rdp_port = chip->port + PDAUDIOCF_REG_MD;
                while (size-- > 0) {
                        inw(rdp_port);
                        inw(rdp_port);
                        inw(rdp_port);
                }
        }
#else
        off = chip->pcm_hwptr + chip->pcm_tdone;
        off %= chip->pcm_size;
        chip->pcm_tdone += size;
        while (size > 0) {
                cont = chip->pcm_size - off;
                if (cont > size)
                        cont = size;
                pdacf_transfer(chip, cont, off);
                off += cont;
                off %= chip->pcm_size;
                size -= cont;
        }
#endif
        mutex_lock(&chip->reg_lock);
        while (chip->pcm_tdone >= chip->pcm_period) {
                chip->pcm_hwptr += chip->pcm_period;
                chip->pcm_hwptr %= chip->pcm_size;
                chip->pcm_tdone -= chip->pcm_period;
                mutex_unlock(&chip->reg_lock);
                snd_pcm_period_elapsed(chip->pcm_substream);
                mutex_lock(&chip->reg_lock);
        }
        mutex_unlock(&chip->reg_lock);
        return IRQ_HANDLED;
}