/*
 * PMac DBDMA lowlevel functions
 *
 * Copyright (c) by Takashi Iwai <tiwai@suse.de>
 * code based on dmasound.c.
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */


#include <asm/io.h>
#include <asm/irq.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <sound/core.h>
#include "pmac.h"
#include <sound/pcm_params.h>
#include <asm/pmac_feature.h>
#include <asm/pci-bridge.h>


/* fixed frequency table for awacs, screamer, burgundy, DACA (44100 max) */
static int awacs_freqs[8] = {
        44100, 29400, 22050, 17640, 14700, 11025, 8820, 7350
};
/* fixed frequency table for tumbler */
static int tumbler_freqs[1] = {
        44100
};


/*
 * we will allocate a single 'emergency' dbdma cmd block to use if the
 * tx status comes up "DEAD".  This happens on some PowerComputing Pmac
 * clones, either owing to a bug in dbdma or some interaction between
 * IDE and sound.  However, this measure would deal with DEAD status if
 * it appeared elsewhere.
 */
static struct pmac_dbdma emergency_dbdma;
static int emergency_in_use;


/*
 * allocate DBDMA command arrays
 */
static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, int size)
{
        unsigned int rsize = sizeof(struct dbdma_cmd) * (size + 1);

        rec->space = dma_alloc_coherent(&chip->pdev->dev, rsize,
                                        &rec->dma_base, GFP_KERNEL);
        if (rec->space == NULL)
                return -ENOMEM;
        rec->size = size;
        memset(rec->space, 0, rsize);
        rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space);
        rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space);

        return 0;
}

static void snd_pmac_dbdma_free(struct snd_pmac *chip, struct pmac_dbdma *rec)
{
        if (rec->space) {
                unsigned int rsize = sizeof(struct dbdma_cmd) * (rec->size + 1);

                dma_free_coherent(&chip->pdev->dev, rsize, rec->space, rec->dma_base);
        }
}


/*
 * pcm stuff
 */

/*
 * look up frequency table
 */

unsigned int snd_pmac_rate_index(struct snd_pmac *chip, struct pmac_stream *rec, unsigned int rate)
{
        int i, ok, found;

        ok = rec->cur_freqs;
        if (rate > chip->freq_table[0])
                return 0;
        found = 0;
        for (i = 0; i < chip->num_freqs; i++, ok >>= 1) {
                if (! (ok & 1)) continue;
                found = i;
                if (rate >= chip->freq_table[i])
                        break;
        }
        return found;
}

/*
 * check whether another stream is active
 */
static inline int another_stream(int stream)
{
        return (stream == SNDRV_PCM_STREAM_PLAYBACK) ?
                SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
}

/*
 * allocate buffers
 */
static int snd_pmac_pcm_hw_params(struct snd_pcm_substream *subs,
                                  struct snd_pcm_hw_params *hw_params)
{
        return snd_pcm_lib_malloc_pages(subs, params_buffer_bytes(hw_params));
}

/*
 * release buffers
 */
static int snd_pmac_pcm_hw_free(struct snd_pcm_substream *subs)
{
        snd_pcm_lib_free_pages(subs);
        return 0;
}

/*
 * get a stream of the opposite direction
 */
static struct pmac_stream *snd_pmac_get_stream(struct snd_pmac *chip, int stream)
{
        switch (stream) {
        case SNDRV_PCM_STREAM_PLAYBACK:
                return &chip->playback;
        case SNDRV_PCM_STREAM_CAPTURE:
                return &chip->capture;
        default:
                snd_BUG();
                return NULL;
        }
}

/*
 * wait while run status is on
 */
static inline void
snd_pmac_wait_ack(struct pmac_stream *rec)
{
        int timeout = 50000;
        while ((in_le32(&rec->dma->status) & RUN) && timeout-- > 0)
                udelay(1);
}

/*
 * set the format and rate to the chip.
 * call the lowlevel function if defined (e.g. for AWACS).
 */
static void snd_pmac_pcm_set_format(struct snd_pmac *chip)
{
        /* set up frequency and format */
        out_le32(&chip->awacs->control, chip->control_mask | (chip->rate_index << 8));
        out_le32(&chip->awacs->byteswap, chip->format == SNDRV_PCM_FORMAT_S16_LE ? 1 : 0);
        if (chip->set_format)
                chip->set_format(chip);
}

/*
 * stop the DMA transfer
 */
static inline void snd_pmac_dma_stop(struct pmac_stream *rec)
{
        out_le32(&rec->dma->control, (RUN|WAKE|FLUSH|PAUSE) << 16);
        snd_pmac_wait_ack(rec);
}

/*
 * set the command pointer address
 */
static inline void snd_pmac_dma_set_command(struct pmac_stream *rec, struct pmac_dbdma *cmd)
{
        out_le32(&rec->dma->cmdptr, cmd->addr);
}

/*
 * start the DMA
 */
static inline void snd_pmac_dma_run(struct pmac_stream *rec, int status)
{
        out_le32(&rec->dma->control, status | (status << 16));
}


/*
 * prepare playback/capture stream
 */
static int snd_pmac_pcm_prepare(struct snd_pmac *chip, struct pmac_stream *rec, struct snd_pcm_substream *subs)
{
        int i;
        volatile struct dbdma_cmd __iomem *cp;
        struct snd_pcm_runtime *runtime = subs->runtime;
        int rate_index;
        long offset;
        struct pmac_stream *astr;

        rec->dma_size = snd_pcm_lib_buffer_bytes(subs);
        rec->period_size = snd_pcm_lib_period_bytes(subs);
        rec->nperiods = rec->dma_size / rec->period_size;
        rec->cur_period = 0;
        rate_index = snd_pmac_rate_index(chip, rec, runtime->rate);

        /* set up constraints */
        astr = snd_pmac_get_stream(chip, another_stream(rec->stream));
        if (! astr)
                return -EINVAL;
        astr->cur_freqs = 1 << rate_index;
        astr->cur_formats = 1 << runtime->format;
        chip->rate_index = rate_index;
        chip->format = runtime->format;

        /* We really want to execute a DMA stop command, after the AWACS
         * is initialized.
         * For reasons I don't understand, it stops the hissing noise
         * common to many PowerBook G3 systems and random noise otherwise
         * captured on iBook2's about every third time. -ReneR
         */
        spin_lock_irq(&chip->reg_lock);
        snd_pmac_dma_stop(rec);
        st_le16(&chip->extra_dma.cmds->command, DBDMA_STOP);
        snd_pmac_dma_set_command(rec, &chip->extra_dma);
        snd_pmac_dma_run(rec, RUN);
        spin_unlock_irq(&chip->reg_lock);
        mdelay(5);
        spin_lock_irq(&chip->reg_lock);
        /* continuous DMA memory type doesn't provide the physical address,
         * so we need to resolve the address here...
         */
        offset = runtime->dma_addr;
        for (i = 0, cp = rec->cmd.cmds; i < rec->nperiods; i++, cp++) {
                st_le32(&cp->phy_addr, offset);
                st_le16(&cp->req_count, rec->period_size);
                /*st_le16(&cp->res_count, 0);*/
                st_le16(&cp->xfer_status, 0);
                offset += rec->period_size;
        }
        /* make loop */
        st_le16(&cp->command, DBDMA_NOP + BR_ALWAYS);
        st_le32(&cp->cmd_dep, rec->cmd.addr);

        snd_pmac_dma_stop(rec);
        snd_pmac_dma_set_command(rec, &rec->cmd);
        spin_unlock_irq(&chip->reg_lock);

        return 0;
}


/*
 * PCM trigger/stop
 */
static int snd_pmac_pcm_trigger(struct snd_pmac *chip, struct pmac_stream *rec,
                                struct snd_pcm_substream *subs, int cmd)
{
        volatile struct dbdma_cmd __iomem *cp;
        int i, command;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
                if (rec->running)
                        return -EBUSY;
                command = (subs->stream == SNDRV_PCM_STREAM_PLAYBACK ?
                           OUTPUT_MORE : INPUT_MORE) + INTR_ALWAYS;
                spin_lock(&chip->reg_lock);
                snd_pmac_beep_stop(chip);
                snd_pmac_pcm_set_format(chip);
                for (i = 0, cp = rec->cmd.cmds; i < rec->nperiods; i++, cp++)
                        out_le16(&cp->command, command);
                snd_pmac_dma_set_command(rec, &rec->cmd);
                (void)in_le32(&rec->dma->status);
                snd_pmac_dma_run(rec, RUN|WAKE);
                rec->running = 1;
                spin_unlock(&chip->reg_lock);
                break;

        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
                spin_lock(&chip->reg_lock);
                rec->running = 0;
                /*printk("stopped!!\n");*/
                snd_pmac_dma_stop(rec);
                for (i = 0, cp = rec->cmd.cmds; i < rec->nperiods; i++, cp++)
                        out_le16(&cp->command, DBDMA_STOP);
                spin_unlock(&chip->reg_lock);
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

/*
 * return the current pointer
 */
inline
static snd_pcm_uframes_t snd_pmac_pcm_pointer(struct snd_pmac *chip,
                                              struct pmac_stream *rec,
                                              struct snd_pcm_substream *subs)
{
        int count = 0;

#if 1 /* hmm.. how can we get the current dma pointer?? */
        int stat;
        volatile struct dbdma_cmd __iomem *cp = &rec->cmd.cmds[rec->cur_period];
        stat = ld_le16(&cp->xfer_status);
        if (stat & (ACTIVE|DEAD)) {
                count = in_le16(&cp->res_count);
                if (count)
                        count = rec->period_size - count;
        }
#endif
        count += rec->cur_period * rec->period_size;
        /*printk("pointer=%d\n", count);*/
        return bytes_to_frames(subs->runtime, count);
}

/*
 * playback
 */

static int snd_pmac_playback_prepare(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);
        return snd_pmac_pcm_prepare(chip, &chip->playback, subs);
}

static int snd_pmac_playback_trigger(struct snd_pcm_substream *subs,
                                     int cmd)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);
        return snd_pmac_pcm_trigger(chip, &chip->playback, subs, cmd);
}

static snd_pcm_uframes_t snd_pmac_playback_pointer(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);
        return snd_pmac_pcm_pointer(chip, &chip->playback, subs);
}


/*
 * capture
 */

static int snd_pmac_capture_prepare(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);
        return snd_pmac_pcm_prepare(chip, &chip->capture, subs);
}

static int snd_pmac_capture_trigger(struct snd_pcm_substream *subs,
                                    int cmd)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);
        return snd_pmac_pcm_trigger(chip, &chip->capture, subs, cmd);
}

static snd_pcm_uframes_t snd_pmac_capture_pointer(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);
        return snd_pmac_pcm_pointer(chip, &chip->capture, subs);
}


/*
 * Handle DEAD DMA transfers:
 * if the TX status comes up "DEAD" - reported on some Power Computing machines
 * we need to re-start the dbdma - but from a different physical start address
 * and with a different transfer length.  It would get very messy to do this
 * with the normal dbdma_cmd blocks - we would have to re-write the buffer start
 * addresses each time.  So, we will keep a single dbdma_cmd block which can be
 * fiddled with.
 * When DEAD status is first reported the content of the faulted dbdma block is
 * copied into the emergency buffer and we note that the buffer is in use.
 * we then bump the start physical address by the amount that was successfully
 * output before it died.
 * On any subsequent DEAD result we just do the bump-ups (we know that we are
 * already using the emergency dbdma_cmd).
 * CHECK: this just tries to "do it".  It is possible that we should abandon
 * xfers when the number of residual bytes gets below a certain value - I can
 * see that this might cause a loop-forever if a too small transfer causes
 * DEAD status.  However this is a TODO for now - we'll see what gets reported.
 * When we get a successful transfer result with the emergency buffer we just
 * pretend that it completed using the original dmdma_cmd and carry on.  The
 * 'next_cmd' field will already point back to the original loop of blocks.
 */
static inline void snd_pmac_pcm_dead_xfer(struct pmac_stream *rec,
                                          volatile struct dbdma_cmd __iomem *cp)
{
        unsigned short req, res ;
        unsigned int phy ;

        /* printk(KERN_WARNING "snd-powermac: DMA died - patching it up!\n"); */

        /* to clear DEAD status we must first clear RUN
           set it to quiescent to be on the safe side */
        (void)in_le32(&rec->dma->status);
        out_le32(&rec->dma->control, (RUN|PAUSE|FLUSH|WAKE) << 16);

        if (!emergency_in_use) { /* new problem */
                memcpy((void *)emergency_dbdma.cmds, (void *)cp,
                       sizeof(struct dbdma_cmd));
                emergency_in_use = 1;
                st_le16(&cp->xfer_status, 0);
                st_le16(&cp->req_count, rec->period_size);
                cp = emergency_dbdma.cmds;
        }

        /* now bump the values to reflect the amount
           we haven't yet shifted */
        req = ld_le16(&cp->req_count);
        res = ld_le16(&cp->res_count);
        phy = ld_le32(&cp->phy_addr);
        phy += (req - res);
        st_le16(&cp->req_count, res);
        st_le16(&cp->res_count, 0);
        st_le16(&cp->xfer_status, 0);
        st_le32(&cp->phy_addr, phy);

        st_le32(&cp->cmd_dep, rec->cmd.addr
                + sizeof(struct dbdma_cmd)*((rec->cur_period+1)%rec->nperiods));

        st_le16(&cp->command, OUTPUT_MORE | BR_ALWAYS | INTR_ALWAYS);

        /* point at our patched up command block */
        out_le32(&rec->dma->cmdptr, emergency_dbdma.addr);

        /* we must re-start the controller */
        (void)in_le32(&rec->dma->status);
        /* should complete clearing the DEAD status */
        out_le32(&rec->dma->control, ((RUN|WAKE) << 16) + (RUN|WAKE));
}

/*
 * update playback/capture pointer from interrupts
 */
static void snd_pmac_pcm_update(struct snd_pmac *chip, struct pmac_stream *rec)
{
        volatile struct dbdma_cmd __iomem *cp;
        int c;
        int stat;

        spin_lock(&chip->reg_lock);
        if (rec->running) {
                for (c = 0; c < rec->nperiods; c++) { /* at most all fragments */

                        if (emergency_in_use)   /* already using DEAD xfer? */
                                cp = emergency_dbdma.cmds;
                        else
                                cp = &rec->cmd.cmds[rec->cur_period];

                        stat = ld_le16(&cp->xfer_status);

                        if (stat & DEAD) {
                                snd_pmac_pcm_dead_xfer(rec, cp);
                                break; /* this block is still going */
                        }

                        if (emergency_in_use)
                                emergency_in_use = 0 ; /* done that */

                        if (! (stat & ACTIVE))
                                break;

                        /*printk("update frag %d\n", rec->cur_period);*/
                        st_le16(&cp->xfer_status, 0);
                        st_le16(&cp->req_count, rec->period_size);
                        /*st_le16(&cp->res_count, 0);*/
                        rec->cur_period++;
                        if (rec->cur_period >= rec->nperiods) {
                                rec->cur_period = 0;
                        }

                        spin_unlock(&chip->reg_lock);
                        snd_pcm_period_elapsed(rec->substream);
                        spin_lock(&chip->reg_lock);
                }
        }
        spin_unlock(&chip->reg_lock);
}


/*
 * hw info
 */

static struct snd_pcm_hardware snd_pmac_playback =
{
        .info =                 (SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_MMAP |
                                 SNDRV_PCM_INFO_MMAP_VALID |
                                 SNDRV_PCM_INFO_RESUME),
        .formats =              SNDRV_PCM_FMTBIT_S16_BE | SNDRV_PCM_FMTBIT_S16_LE,
        .rates =                SNDRV_PCM_RATE_8000_44100,
        .rate_min =             7350,
        .rate_max =             44100,
        .channels_min =         2,
        .channels_max =         2,
        .buffer_bytes_max =     131072,
        .period_bytes_min =     256,
        .period_bytes_max =     16384,
        .periods_min =          3,
        .periods_max =          PMAC_MAX_FRAGS,
};

static struct snd_pcm_hardware snd_pmac_capture =
{
        .info =                 (SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_MMAP |
                                 SNDRV_PCM_INFO_MMAP_VALID |
                                 SNDRV_PCM_INFO_RESUME),
        .formats =              SNDRV_PCM_FMTBIT_S16_BE | SNDRV_PCM_FMTBIT_S16_LE,
        .rates =                SNDRV_PCM_RATE_8000_44100,
        .rate_min =             7350,
        .rate_max =             44100,
        .channels_min =         2,
        .channels_max =         2,
        .buffer_bytes_max =     131072,
        .period_bytes_min =     256,
        .period_bytes_max =     16384,
        .periods_min =          3,
        .periods_max =          PMAC_MAX_FRAGS,
};


#if 0 // NYI
static int snd_pmac_hw_rule_rate(struct snd_pcm_hw_params *params,
                                 struct snd_pcm_hw_rule *rule)
{
        struct snd_pmac *chip = rule->private;
        struct pmac_stream *rec = snd_pmac_get_stream(chip, rule->deps[0]);
        int i, freq_table[8], num_freqs;

        if (! rec)
                return -EINVAL;
        num_freqs = 0;
        for (i = chip->num_freqs - 1; i >= 0; i--) {
                if (rec->cur_freqs & (1 << i))
                        freq_table[num_freqs++] = chip->freq_table[i];
        }

        return snd_interval_list(hw_param_interval(params, rule->var),
                                 num_freqs, freq_table, 0);
}

static int snd_pmac_hw_rule_format(struct snd_pcm_hw_params *params,
                                   struct snd_pcm_hw_rule *rule)
{
        struct snd_pmac *chip = rule->private;
        struct pmac_stream *rec = snd_pmac_get_stream(chip, rule->deps[0]);

        if (! rec)
                return -EINVAL;
        return snd_mask_refine_set(hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT),
                                   rec->cur_formats);
}
#endif // NYI

static int snd_pmac_pcm_open(struct snd_pmac *chip, struct pmac_stream *rec,
                             struct snd_pcm_substream *subs)
{
        struct snd_pcm_runtime *runtime = subs->runtime;
        int i;

        /* look up frequency table and fill bit mask */
        runtime->hw.rates = 0;
        for (i = 0; i < chip->num_freqs; i++)
                if (chip->freqs_ok & (1 << i))
                        runtime->hw.rates |=
                                snd_pcm_rate_to_rate_bit(chip->freq_table[i]);

        /* check for minimum and maximum rates */
        for (i = 0; i < chip->num_freqs; i++) {
                if (chip->freqs_ok & (1 << i)) {
                        runtime->hw.rate_max = chip->freq_table[i];
                        break;
                }
        }
        for (i = chip->num_freqs - 1; i >= 0; i--) {
                if (chip->freqs_ok & (1 << i)) {
                        runtime->hw.rate_min = chip->freq_table[i];
                        break;
                }
        }
        runtime->hw.formats = chip->formats_ok;
        if (chip->can_capture) {
                if (! chip->can_duplex)
                        runtime->hw.info |= SNDRV_PCM_INFO_HALF_DUPLEX;
                runtime->hw.info |= SNDRV_PCM_INFO_JOINT_DUPLEX;
        }
        runtime->private_data = rec;
        rec->substream = subs;

#if 0 /* FIXME: still under development.. */
        snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
                            snd_pmac_hw_rule_rate, chip, rec->stream, -1);
        snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
                            snd_pmac_hw_rule_format, chip, rec->stream, -1);
#endif

        runtime->hw.periods_max = rec->cmd.size - 1;

        /* constraints to fix choppy sound */
        snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
        return 0;
}

static int snd_pmac_pcm_close(struct snd_pmac *chip, struct pmac_stream *rec,
                              struct snd_pcm_substream *subs)
{
        struct pmac_stream *astr;

        snd_pmac_dma_stop(rec);

        astr = snd_pmac_get_stream(chip, another_stream(rec->stream));
        if (! astr)
                return -EINVAL;

        /* reset constraints */
        astr->cur_freqs = chip->freqs_ok;
        astr->cur_formats = chip->formats_ok;

        return 0;
}

static int snd_pmac_playback_open(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);

        subs->runtime->hw = snd_pmac_playback;
        return snd_pmac_pcm_open(chip, &chip->playback, subs);
}

static int snd_pmac_capture_open(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);

        subs->runtime->hw = snd_pmac_capture;
        return snd_pmac_pcm_open(chip, &chip->capture, subs);
}

static int snd_pmac_playback_close(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);

        return snd_pmac_pcm_close(chip, &chip->playback, subs);
}

static int snd_pmac_capture_close(struct snd_pcm_substream *subs)
{
        struct snd_pmac *chip = snd_pcm_substream_chip(subs);

        return snd_pmac_pcm_close(chip, &chip->capture, subs);
}

/*
 */

static struct snd_pcm_ops snd_pmac_playback_ops = {
        .open =         snd_pmac_playback_open,
        .close =        snd_pmac_playback_close,
        .ioctl =        snd_pcm_lib_ioctl,
        .hw_params =    snd_pmac_pcm_hw_params,
        .hw_free =      snd_pmac_pcm_hw_free,
        .prepare =      snd_pmac_playback_prepare,
        .trigger =      snd_pmac_playback_trigger,
        .pointer =      snd_pmac_playback_pointer,
};

static struct snd_pcm_ops snd_pmac_capture_ops = {
        .open =         snd_pmac_capture_open,
        .close =        snd_pmac_capture_close,
        .ioctl =        snd_pcm_lib_ioctl,
        .hw_params =    snd_pmac_pcm_hw_params,
        .hw_free =      snd_pmac_pcm_hw_free,
        .prepare =      snd_pmac_capture_prepare,
        .trigger =      snd_pmac_capture_trigger,
        .pointer =      snd_pmac_capture_pointer,
};

int __init snd_pmac_pcm_new(struct snd_pmac *chip)
{
        struct snd_pcm *pcm;
        int err;
        int num_captures = 1;

        if (! chip->can_capture)
                num_captures = 0;
        err = snd_pcm_new(chip->card, chip->card->driver, 0, 1, num_captures, &pcm);
        if (err < 0)
                return err;

        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_pmac_playback_ops);
        if (chip->can_capture)
                snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_pmac_capture_ops);

        pcm->private_data = chip;
        pcm->info_flags = SNDRV_PCM_INFO_JOINT_DUPLEX;
        strcpy(pcm->name, chip->card->shortname);
        chip->pcm = pcm;

        chip->formats_ok = SNDRV_PCM_FMTBIT_S16_BE;
        if (chip->can_byte_swap)
                chip->formats_ok |= SNDRV_PCM_FMTBIT_S16_LE;

        chip->playback.cur_formats = chip->formats_ok;
        chip->capture.cur_formats = chip->formats_ok;
        chip->playback.cur_freqs = chip->freqs_ok;
        chip->capture.cur_freqs = chip->freqs_ok;

        /* preallocate 64k buffer */
        snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
                                              &chip->pdev->dev,
                                              64 * 1024, 64 * 1024);

        return 0;
}


static void snd_pmac_dbdma_reset(struct snd_pmac *chip)
{
        out_le32(&chip->playback.dma->control, (RUN|PAUSE|FLUSH|WAKE|DEAD) << 16);
        snd_pmac_wait_ack(&chip->playback);
        out_le32(&chip->capture.dma->control, (RUN|PAUSE|FLUSH|WAKE|DEAD) << 16);
        snd_pmac_wait_ack(&chip->capture);
}


/*
 * handling beep
 */
void snd_pmac_beep_dma_start(struct snd_pmac *chip, int bytes, unsigned long addr, int speed)
{
        struct pmac_stream *rec = &chip->playback;

        snd_pmac_dma_stop(rec);
        st_le16(&chip->extra_dma.cmds->req_count, bytes);
        st_le16(&chip->extra_dma.cmds->xfer_status, 0);
        st_le32(&chip->extra_dma.cmds->cmd_dep, chip->extra_dma.addr);
        st_le32(&chip->extra_dma.cmds->phy_addr, addr);
        st_le16(&chip->extra_dma.cmds->command, OUTPUT_MORE + BR_ALWAYS);
        out_le32(&chip->awacs->control,
                 (in_le32(&chip->awacs->control) & ~0x1f00)
                 | (speed << 8));
        out_le32(&chip->awacs->byteswap, 0);
        snd_pmac_dma_set_command(rec, &chip->extra_dma);
        snd_pmac_dma_run(rec, RUN);
}

void snd_pmac_beep_dma_stop(struct snd_pmac *chip)
{
        snd_pmac_dma_stop(&chip->playback);
        st_le16(&chip->extra_dma.cmds->command, DBDMA_STOP);
        snd_pmac_pcm_set_format(chip); /* reset format */
}


/*
 * interrupt handlers
 */
static irqreturn_t
snd_pmac_tx_intr(int irq, void *devid)
{
        struct snd_pmac *chip = devid;
        snd_pmac_pcm_update(chip, &chip->playback);
        return IRQ_HANDLED;
}


static irqreturn_t
snd_pmac_rx_intr(int irq, void *devid)
{
        struct snd_pmac *chip = devid;
        snd_pmac_pcm_update(chip, &chip->capture);
        return IRQ_HANDLED;
}


static irqreturn_t
snd_pmac_ctrl_intr(int irq, void *devid)
{
        struct snd_pmac *chip = devid;
        int ctrl = in_le32(&chip->awacs->control);

        /*printk("pmac: control interrupt.. 0x%x\n", ctrl);*/
        if (ctrl & MASK_PORTCHG) {
                /* do something when headphone is plugged/unplugged? */
                if (chip->update_automute)
                        chip->update_automute(chip, 1);
        }
        if (ctrl & MASK_CNTLERR) {
                int err = (in_le32(&chip->awacs->codec_stat) & MASK_ERRCODE) >> 16;
                if (err && chip->model <= PMAC_SCREAMER)
                        snd_printk(KERN_DEBUG "error %x\n", err);
        }
        /* Writing 1s to the CNTLERR and PORTCHG bits clears them... */
        out_le32(&chip->awacs->control, ctrl);
        return IRQ_HANDLED;
}


/*
 * a wrapper to feature call for compatibility
 */
static void snd_pmac_sound_feature(struct snd_pmac *chip, int enable)
{
        if (ppc_md.feature_call)
                ppc_md.feature_call(PMAC_FTR_SOUND_CHIP_ENABLE, chip->node, 0, enable);
}

/*
 * release resources
 */

static int snd_pmac_free(struct snd_pmac *chip)
{
        /* stop sounds */
        if (chip->initialized) {
                snd_pmac_dbdma_reset(chip);
                /* disable interrupts from awacs interface */
                out_le32(&chip->awacs->control, in_le32(&chip->awacs->control) & 0xfff);
        }

        if (chip->node)
                snd_pmac_sound_feature(chip, 0);

        /* clean up mixer if any */
        if (chip->mixer_free)
                chip->mixer_free(chip);

        snd_pmac_detach_beep(chip);

        /* release resources */
        if (chip->irq >= 0)
                free_irq(chip->irq, (void*)chip);
        if (chip->tx_irq >= 0)
                free_irq(chip->tx_irq, (void*)chip);
        if (chip->rx_irq >= 0)
                free_irq(chip->rx_irq, (void*)chip);
        snd_pmac_dbdma_free(chip, &chip->playback.cmd);
        snd_pmac_dbdma_free(chip, &chip->capture.cmd);
        snd_pmac_dbdma_free(chip, &chip->extra_dma);
        snd_pmac_dbdma_free(chip, &emergency_dbdma);
        if (chip->macio_base)
                iounmap(chip->macio_base);
        if (chip->latch_base)
                iounmap(chip->latch_base);
        if (chip->awacs)
                iounmap(chip->awacs);
        if (chip->playback.dma)
                iounmap(chip->playback.dma);
        if (chip->capture.dma)
                iounmap(chip->capture.dma);

        if (chip->node) {
                int i;
                for (i = 0; i < 3; i++) {
                        if (chip->requested & (1 << i))
                                release_mem_region(chip->rsrc[i].start,
                                                   chip->rsrc[i].end -
                                                   chip->rsrc[i].start + 1);
                }
        }

        if (chip->pdev)
                pci_dev_put(chip->pdev);
        of_node_put(chip->node);
        kfree(chip);
        return 0;
}


/*
 * free the device
 */
static int snd_pmac_dev_free(struct snd_device *device)
{
        struct snd_pmac *chip = device->device_data;
        return snd_pmac_free(chip);
}


/*
 * check the machine support byteswap (little-endian)
 */

static void __init detect_byte_swap(struct snd_pmac *chip)
{
        struct device_node *mio;

        /* if seems that Keylargo can't byte-swap  */
        for (mio = chip->node->parent; mio; mio = mio->parent) {
                if (strcmp(mio->name, "mac-io") == 0) {
                        if (of_device_is_compatible(mio, "Keylargo"))
                                chip->can_byte_swap = 0;
                        break;
                }
        }

        /* it seems the Pismo & iBook can't byte-swap in hardware. */
        if (machine_is_compatible("PowerBook3,1") ||
            machine_is_compatible("PowerBook2,1"))
                chip->can_byte_swap = 0 ;

        if (machine_is_compatible("PowerBook2,1"))
                chip->can_duplex = 0;
}


/*
 * detect a sound chip
 */
static int __init snd_pmac_detect(struct snd_pmac *chip)
{
        struct device_node *sound;
        struct device_node *dn;
        const unsigned int *prop;
        unsigned int l;
        struct macio_chip* macio;

        if (!machine_is(powermac))
                return -ENODEV;

        chip->subframe = 0;
        chip->revision = 0;
        chip->freqs_ok = 0xff; /* all ok */
        chip->model = PMAC_AWACS;
        chip->can_byte_swap = 1;
        chip->can_duplex = 1;
        chip->can_capture = 1;
        chip->num_freqs = ARRAY_SIZE(awacs_freqs);
        chip->freq_table = awacs_freqs;
        chip->pdev = NULL;

        chip->control_mask = MASK_IEPC | MASK_IEE | 0x11; /* default */

        /* check machine type */
        if (machine_is_compatible("AAPL,3400/2400")
            || machine_is_compatible("AAPL,3500"))
                chip->is_pbook_3400 = 1;
        else if (machine_is_compatible("PowerBook1,1")
                 || machine_is_compatible("AAPL,PowerBook1998"))
                chip->is_pbook_G3 = 1;
        chip->node = of_find_node_by_name(NULL, "awacs");
        sound = of_node_get(chip->node);

        /*
         * powermac G3 models have a node called "davbus"
         * with a child called "sound".
         */
        if (!chip->node)
                chip->node = of_find_node_by_name(NULL, "davbus");
        /*
         * if we didn't find a davbus device, try 'i2s-a' since
         * this seems to be what iBooks have
         */
        if (! chip->node) {
                chip->node = of_find_node_by_name(NULL, "i2s-a");
                if (chip->node && chip->node->parent &&
                    chip->node->parent->parent) {
                        if (of_device_is_compatible(chip->node->parent->parent,
                                                 "K2-Keylargo"))
                                chip->is_k2 = 1;
                }
        }
        if (! chip->node)
                return -ENODEV;

        if (!sound) {
                sound = of_find_node_by_name(NULL, "sound");
                while (sound && sound->parent != chip->node)
                        sound = of_find_node_by_name(sound, "sound");
        }
        if (! sound) {
                of_node_put(chip->node);
                chip->node = NULL;

                return -ENODEV;
        }
        prop = of_get_property(sound, "sub-frame", NULL);
        if (prop && *prop < 16)
                chip->subframe = *prop;
        prop = of_get_property(sound, "layout-id", NULL);
        if (prop) {
                /* partly deprecate snd-powermac, for those machines
                 * that have a layout-id property for now */
                printk(KERN_INFO "snd-powermac no longer handles any "
                                 "machines with a layout-id property "
                                 "in the device-tree, use snd-aoa.\n");
                of_node_put(sound);
                of_node_put(chip->node);
                chip->node = NULL;
                return -ENODEV;
        }
        /* This should be verified on older screamers */
        if (of_device_is_compatible(sound, "screamer")) {
                chip->model = PMAC_SCREAMER;
                // chip->can_byte_swap = 0; /* FIXME: check this */
        }
        if (of_device_is_compatible(sound, "burgundy")) {
                chip->model = PMAC_BURGUNDY;
                chip->control_mask = MASK_IEPC | 0x11; /* disable IEE */
        }
        if (of_device_is_compatible(sound, "daca")) {
                chip->model = PMAC_DACA;
                chip->can_capture = 0;  /* no capture */
                chip->can_duplex = 0;
                // chip->can_byte_swap = 0; /* FIXME: check this */
                chip->control_mask = MASK_IEPC | 0x11; /* disable IEE */
        }
        if (of_device_is_compatible(sound, "tumbler")) {
                chip->model = PMAC_TUMBLER;
                chip->can_capture = 0;  /* no capture */
                chip->can_duplex = 0;
                // chip->can_byte_swap = 0; /* FIXME: check this */
                chip->num_freqs = ARRAY_SIZE(tumbler_freqs);
                chip->freq_table = tumbler_freqs;
                chip->control_mask = MASK_IEPC | 0x11; /* disable IEE */
        }
        if (of_device_is_compatible(sound, "snapper")) {
                chip->model = PMAC_SNAPPER;
                // chip->can_byte_swap = 0; /* FIXME: check this */
                chip->num_freqs = ARRAY_SIZE(tumbler_freqs);
                chip->freq_table = tumbler_freqs;
                chip->control_mask = MASK_IEPC | 0x11; /* disable IEE */
        }
        prop = of_get_property(sound, "device-id", NULL);
        if (prop)
                chip->device_id = *prop;
        dn = of_find_node_by_name(NULL, "perch");
        chip->has_iic = (dn != NULL);
        of_node_put(dn);

        /* We need the PCI device for DMA allocations, let's use a crude method
         * for now ...
         */
        macio = macio_find(chip->node, macio_unknown);
        if (macio == NULL)
                printk(KERN_WARNING "snd-powermac: can't locate macio !\n");
        else {
                struct pci_dev *pdev = NULL;

                for_each_pci_dev(pdev) {
                        struct device_node *np = pci_device_to_OF_node(pdev);
                        if (np && np == macio->of_node) {
                                chip->pdev = pdev;
                                break;
                        }
                }
        }
        if (chip->pdev == NULL)
                printk(KERN_WARNING "snd-powermac: can't locate macio PCI"
                       " device !\n");

        detect_byte_swap(chip);

        /* look for a property saying what sample rates
           are available */
        prop = of_get_property(sound, "sample-rates", &l);
        if (! prop)
                prop = of_get_property(sound, "output-frame-rates", &l);
        if (prop) {
                int i;
                chip->freqs_ok = 0;
                for (l /= sizeof(int); l > 0; --l) {
                        unsigned int r = *prop++;
                        /* Apple 'Fixed' format */
                        if (r >= 0x10000)
                                r >>= 16;
                        for (i = 0; i < chip->num_freqs; ++i) {
                                if (r == chip->freq_table[i]) {
                                        chip->freqs_ok |= (1 << i);
                                        break;
                                }
                        }
                }
        } else {
                /* assume only 44.1khz */
                chip->freqs_ok = 1;
        }

        of_node_put(sound);
        return 0;
}

#ifdef PMAC_SUPPORT_AUTOMUTE
/*
 * auto-mute
 */
static int pmac_auto_mute_get(struct snd_kcontrol *kcontrol,
                              struct snd_ctl_elem_value *ucontrol)
{
        struct snd_pmac *chip = snd_kcontrol_chip(kcontrol);
        ucontrol->value.integer.value[0] = chip->auto_mute;
        return 0;
}

static int pmac_auto_mute_put(struct snd_kcontrol *kcontrol,
                              struct snd_ctl_elem_value *ucontrol)
{
        struct snd_pmac *chip = snd_kcontrol_chip(kcontrol);
        if (ucontrol->value.integer.value[0] != chip->auto_mute) {
                chip->auto_mute = !!ucontrol->value.integer.value[0];
                if (chip->update_automute)
                        chip->update_automute(chip, 1);
                return 1;
        }
        return 0;
}

static int pmac_hp_detect_get(struct snd_kcontrol *kcontrol,
                              struct snd_ctl_elem_value *ucontrol)
{
        struct snd_pmac *chip = snd_kcontrol_chip(kcontrol);
        if (chip->detect_headphone)
                ucontrol->value.integer.value[0] = chip->detect_headphone(chip);
        else
                ucontrol->value.integer.value[0] = 0;
        return 0;
}

static struct snd_kcontrol_new auto_mute_controls[] __initdata = {
        { .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
          .name = "Auto Mute Switch",
          .info = snd_pmac_boolean_mono_info,
          .get = pmac_auto_mute_get,
          .put = pmac_auto_mute_put,
        },
        { .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
          .name = "Headphone Detection",
          .access = SNDRV_CTL_ELEM_ACCESS_READ,
          .info = snd_pmac_boolean_mono_info,
          .get = pmac_hp_detect_get,
        },
};

int __init snd_pmac_add_automute(struct snd_pmac *chip)
{
        int err;
        chip->auto_mute = 1;
        err = snd_ctl_add(chip->card, snd_ctl_new1(&auto_mute_controls[0], chip));
        if (err < 0) {
                printk(KERN_ERR "snd-powermac: Failed to add automute control\n");
                return err;
        }
        chip->hp_detect_ctl = snd_ctl_new1(&auto_mute_controls[1], chip);
        return snd_ctl_add(chip->card, chip->hp_detect_ctl);
}
#endif /* PMAC_SUPPORT_AUTOMUTE */

/*
 * create and detect a pmac chip record
 */
int __init snd_pmac_new(struct snd_card *card, struct snd_pmac **chip_return)
{
        struct snd_pmac *chip;
        struct device_node *np;
        int i, err;
        unsigned int irq;
        unsigned long ctrl_addr, txdma_addr, rxdma_addr;
        static struct snd_device_ops ops = {
                .dev_free =     snd_pmac_dev_free,
        };

        *chip_return = NULL;

        chip = kzalloc(sizeof(*chip), GFP_KERNEL);
        if (chip == NULL)
                return -ENOMEM;
        chip->card = card;

        spin_lock_init(&chip->reg_lock);
        chip->irq = chip->tx_irq = chip->rx_irq = -1;

        chip->playback.stream = SNDRV_PCM_STREAM_PLAYBACK;
        chip->capture.stream = SNDRV_PCM_STREAM_CAPTURE;

        if ((err = snd_pmac_detect(chip)) < 0)
                goto __error;

        if (snd_pmac_dbdma_alloc(chip, &chip->playback.cmd, PMAC_MAX_FRAGS + 1) < 0 ||
            snd_pmac_dbdma_alloc(chip, &chip->capture.cmd, PMAC_MAX_FRAGS + 1) < 0 ||
            snd_pmac_dbdma_alloc(chip, &chip->extra_dma, 2) < 0 ||
            snd_pmac_dbdma_alloc(chip, &emergency_dbdma, 2) < 0) {
                err = -ENOMEM;
                goto __error;
        }

        np = chip->node;
        chip->requested = 0;
        if (chip->is_k2) {
                static char *rnames[] = {
                        "Sound Control", "Sound DMA" };
                for (i = 0; i < 2; i ++) {
                        if (of_address_to_resource(np->parent, i,
                                                   &chip->rsrc[i])) {
                                printk(KERN_ERR "snd: can't translate rsrc "
                                       " %d (%s)\n", i, rnames[i]);
                                err = -ENODEV;
                                goto __error;
                        }
                        if (request_mem_region(chip->rsrc[i].start,
                                               chip->rsrc[i].end -
                                               chip->rsrc[i].start + 1,
                                               rnames[i]) == NULL) {
                                printk(KERN_ERR "snd: can't request rsrc "
                                       " %d (%s: 0x%016llx:%016llx)\n",
                                       i, rnames[i],
                                       (unsigned long long)chip->rsrc[i].start,
                                       (unsigned long long)chip->rsrc[i].end);
                                err = -ENODEV;
                                goto __error;
                        }
                        chip->requested |= (1 << i);
                }
                ctrl_addr = chip->rsrc[0].start;
                txdma_addr = chip->rsrc[1].start;
                rxdma_addr = txdma_addr + 0x100;
        } else {
                static char *rnames[] = {
                        "Sound Control", "Sound Tx DMA", "Sound Rx DMA" };
                for (i = 0; i < 3; i ++) {
                        if (of_address_to_resource(np, i,
                                                   &chip->rsrc[i])) {
                                printk(KERN_ERR "snd: can't translate rsrc "
                                       " %d (%s)\n", i, rnames[i]);
                                err = -ENODEV;
                                goto __error;
                        }
                        if (request_mem_region(chip->rsrc[i].start,
                                               chip->rsrc[i].end -
                                               chip->rsrc[i].start + 1,
                                               rnames[i]) == NULL) {
                                printk(KERN_ERR "snd: can't request rsrc "
                                       " %d (%s: 0x%016llx:%016llx)\n",
                                       i, rnames[i],
                                       (unsigned long long)chip->rsrc[i].start,
                                       (unsigned long long)chip->rsrc[i].end);
                                err = -ENODEV;
                                goto __error;
                        }
                        chip->requested |= (1 << i);
                }
                ctrl_addr = chip->rsrc[0].start;
                txdma_addr = chip->rsrc[1].start;
                rxdma_addr = chip->rsrc[2].start;
        }

        chip->awacs = ioremap(ctrl_addr, 0x1000);
        chip->playback.dma = ioremap(txdma_addr, 0x100);
        chip->capture.dma = ioremap(rxdma_addr, 0x100);
        if (chip->model <= PMAC_BURGUNDY) {
                irq = irq_of_parse_and_map(np, 0);
                if (request_irq(irq, snd_pmac_ctrl_intr, 0,
                                "PMac", (void*)chip)) {
                        snd_printk(KERN_ERR "pmac: unable to grab IRQ %d\n",
                                   irq);
                        err = -EBUSY;
                        goto __error;
                }
                chip->irq = irq;
        }
        irq = irq_of_parse_and_map(np, 1);
        if (request_irq(irq, snd_pmac_tx_intr, 0, "PMac Output", (void*)chip)){
                snd_printk(KERN_ERR "pmac: unable to grab IRQ %d\n", irq);
                err = -EBUSY;
                goto __error;
        }
        chip->tx_irq = irq;
        irq = irq_of_parse_and_map(np, 2);
        if (request_irq(irq, snd_pmac_rx_intr, 0, "PMac Input", (void*)chip)) {
                snd_printk(KERN_ERR "pmac: unable to grab IRQ %d\n", irq);
                err = -EBUSY;
                goto __error;
        }
        chip->rx_irq = irq;

        snd_pmac_sound_feature(chip, 1);

        /* reset & enable interrupts */
        if (chip->model <= PMAC_BURGUNDY)
                out_le32(&chip->awacs->control, chip->control_mask);

        /* Powerbooks have odd ways of enabling inputs such as
           an expansion-bay CD or sound from an internal modem
           or a PC-card modem. */
        if (chip->is_pbook_3400) {
                /* Enable CD and PC-card sound inputs. */
                /* This is done by reading from address
                 * f301a000, + 0x10 to enable the expansion-bay
                 * CD sound input, + 0x80 to enable the PC-card
                 * sound input.  The 0x100 enables the SCSI bus
                 * terminator power.
                 */
                chip->latch_base = ioremap (0xf301a000, 0x1000);
                in_8(chip->latch_base + 0x190);
        } else if (chip->is_pbook_G3) {
                struct device_node* mio;
                for (mio = chip->node->parent; mio; mio = mio->parent) {
                        if (strcmp(mio->name, "mac-io") == 0) {
                                struct resource r;
                                if (of_address_to_resource(mio, 0, &r) == 0)
                                        chip->macio_base =
                                                ioremap(r.start, 0x40);
                                break;
                        }
                }
                /* Enable CD sound input. */
                /* The relevant bits for writing to this byte are 0x8f.
                 * I haven't found out what the 0x80 bit does.
                 * For the 0xf bits, writing 3 or 7 enables the CD
                 * input, any other value disables it.  Values
                 * 1, 3, 5, 7 enable the microphone.  Values 0, 2,
                 * 4, 6, 8 - f enable the input from the modem.
                 */
                if (chip->macio_base)
                        out_8(chip->macio_base + 0x37, 3);
        }

        /* Reset dbdma channels */
        snd_pmac_dbdma_reset(chip);

        if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0)
                goto __error;

        *chip_return = chip;
        return 0;

 __error:
        snd_pmac_free(chip);
        return err;
}


/*
 * sleep notify for powerbook
 */

#ifdef CONFIG_PM

/*
 * Save state when going to sleep, restore it afterwards.
 */

void snd_pmac_suspend(struct snd_pmac *chip)
{
        unsigned long flags;

        snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
        if (chip->suspend)
                chip->suspend(chip);
        snd_pcm_suspend_all(chip->pcm);
        spin_lock_irqsave(&chip->reg_lock, flags);
        snd_pmac_beep_stop(chip);
        spin_unlock_irqrestore(&chip->reg_lock, flags);
        if (chip->irq >= 0)
                disable_irq(chip->irq);
        if (chip->tx_irq >= 0)
                disable_irq(chip->tx_irq);
        if (chip->rx_irq >= 0)
                disable_irq(chip->rx_irq);
        snd_pmac_sound_feature(chip, 0);
}

void snd_pmac_resume(struct snd_pmac *chip)
{
        snd_pmac_sound_feature(chip, 1);
        if (chip->resume)
                chip->resume(chip);
        /* enable CD sound input */
        if (chip->macio_base && chip->is_pbook_G3)
                out_8(chip->macio_base + 0x37, 3);
        else if (chip->is_pbook_3400)
                in_8(chip->latch_base + 0x190);

        snd_pmac_pcm_set_format(chip);

        if (chip->irq >= 0)
                enable_irq(chip->irq);
        if (chip->tx_irq >= 0)
                enable_irq(chip->tx_irq);
        if (chip->rx_irq >= 0)
                enable_irq(chip->rx_irq);

        snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
}

#endif /* CONFIG_PM */