cx23885-alsa.c

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/*
 *
 *  Support for CX23885 analog audio capture
 *
 *    (c) 2008 Mijhail Moreyra <[email protected]>
 *    Adapted from cx88-alsa.c
 *    (c) 2009 Steven Toth <[email protected]>
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/vmalloc.h>
#include <linux/dma-mapping.h>
#include <linux/pci.h>

#include <asm/delay.h>

#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/control.h>
#include <sound/initval.h>

#include <sound/tlv.h>


#include "cx23885.h"
#include "cx23885-reg.h"

#define AUDIO_SRAM_CHANNEL  SRAM_CH07

#define dprintk(level, fmt, arg...) if (audio_debug >= level) \
    printk(KERN_INFO "%s: " fmt, chip->dev->name , ## arg)

#define dprintk_core(level, fmt, arg...)    if (audio_debug >= level) \
    printk(KERN_DEBUG "%s: " fmt, chip->dev->name , ## arg)

/****************************************************************************
            Module global static vars
 ****************************************************************************/

static unsigned int disable_analog_audio;
module_param(disable_analog_audio, int, 0644);
MODULE_PARM_DESC(disable_analog_audio, "disable analog audio ALSA driver");

static unsigned int audio_debug;
module_param(audio_debug, int, 0644);
MODULE_PARM_DESC(audio_debug, "enable debug messages [analog audio]");

/****************************************************************************
            Board specific funtions
 ****************************************************************************/

/* Constants taken from cx88-reg.h */
#define AUD_INT_DN_RISCI1       (1 <<  0)
#define AUD_INT_UP_RISCI1       (1 <<  1)
#define AUD_INT_RDS_DN_RISCI1   (1 <<  2)
#define AUD_INT_DN_RISCI2       (1 <<  4) /* yes, 3 is skipped */
#define AUD_INT_UP_RISCI2       (1 <<  5)
#define AUD_INT_RDS_DN_RISCI2   (1 <<  6)
#define AUD_INT_DN_SYNC         (1 << 12)
#define AUD_INT_UP_SYNC         (1 << 13)
#define AUD_INT_RDS_DN_SYNC     (1 << 14)
#define AUD_INT_OPC_ERR         (1 << 16)
#define AUD_INT_BER_IRQ         (1 << 20)
#define AUD_INT_MCHG_IRQ        (1 << 21)
#define GP_COUNT_CONTROL_RESET  0x3

/*
 * BOARD Specific: Sets audio DMA
 */

static int cx23885_start_audio_dma(struct cx23885_audio_dev *chip)
{
    struct cx23885_audio_buffer *buf = chip->buf;
    struct cx23885_dev *dev  = chip->dev;
    struct sram_channel *audio_ch =
        &dev->sram_channels[AUDIO_SRAM_CHANNEL];

    dprintk(1, "%s()\n", __func__);

    /* Make sure RISC/FIFO are off before changing FIFO/RISC settings */
    cx_clear(AUD_INT_DMA_CTL, 0x11);

    /* setup fifo + format - out channel */
    cx23885_sram_channel_setup(chip->dev, audio_ch, buf->bpl,
        buf->risc.dma);

    /* sets bpl size */
    cx_write(AUD_INT_A_LNGTH, buf->bpl);

    /* This is required to get good audio (1 seems to be ok) */
    cx_write(AUD_INT_A_MODE, 1);

    /* reset counter */
    cx_write(AUD_INT_A_GPCNT_CTL, GP_COUNT_CONTROL_RESET);
    atomic_set(&chip->count, 0);

    dprintk(1, "Start audio DMA, %d B/line, %d lines/FIFO, %d periods, %d "
        "byte buffer\n", buf->bpl, cx_read(audio_ch->cmds_start+12)>>1,
        chip->num_periods, buf->bpl * chip->num_periods);

    /* Enables corresponding bits at AUD_INT_STAT */
    cx_write(AUDIO_INT_INT_MSK, AUD_INT_OPC_ERR | AUD_INT_DN_SYNC |
                    AUD_INT_DN_RISCI1);

    /* Clean any pending interrupt bits already set */
    cx_write(AUDIO_INT_INT_STAT, ~0);

    /* enable audio irqs */
    cx_set(PCI_INT_MSK, chip->dev->pci_irqmask | PCI_MSK_AUD_INT);

    /* start dma */
    cx_set(DEV_CNTRL2, (1<<5)); /* Enables Risc Processor */
    cx_set(AUD_INT_DMA_CTL, 0x11); /* audio downstream FIFO and
                      RISC enable */
    if (audio_debug)
        cx23885_sram_channel_dump(chip->dev, audio_ch);

    return 0;
}

/*
 * BOARD Specific: Resets audio DMA
 */
static int cx23885_stop_audio_dma(struct cx23885_audio_dev *chip)
{
    struct cx23885_dev *dev = chip->dev;
    dprintk(1, "Stopping audio DMA\n");

    /* stop dma */
    cx_clear(AUD_INT_DMA_CTL, 0x11);

    /* disable irqs */
    cx_clear(PCI_INT_MSK, PCI_MSK_AUD_INT);
    cx_clear(AUDIO_INT_INT_MSK, AUD_INT_OPC_ERR | AUD_INT_DN_SYNC |
                    AUD_INT_DN_RISCI1);

    if (audio_debug)
        cx23885_sram_channel_dump(chip->dev,
            &dev->sram_channels[AUDIO_SRAM_CHANNEL]);

    return 0;
}

/*
 * BOARD Specific: Handles audio IRQ
 */
int cx23885_audio_irq(struct cx23885_dev *dev, u32 status, u32 mask)
{
    struct cx23885_audio_dev *chip = dev->audio_dev;

    if (0 == (status & mask))
        return 0;

    cx_write(AUDIO_INT_INT_STAT, status);

    /* risc op code error */
    if (status & AUD_INT_OPC_ERR) {
        printk(KERN_WARNING "%s/1: Audio risc op code error\n",
            dev->name);
        cx_clear(AUD_INT_DMA_CTL, 0x11);
        cx23885_sram_channel_dump(dev,
            &dev->sram_channels[AUDIO_SRAM_CHANNEL]);
    }
    if (status & AUD_INT_DN_SYNC) {
        dprintk(1, "Downstream sync error\n");
        cx_write(AUD_INT_A_GPCNT_CTL, GP_COUNT_CONTROL_RESET);
        return 1;
    }
    /* risc1 downstream */
    if (status & AUD_INT_DN_RISCI1) {
        atomic_set(&chip->count, cx_read(AUD_INT_A_GPCNT));
        snd_pcm_period_elapsed(chip->substream);
    }
    /* FIXME: Any other status should deserve a special handling? */

    return 1;
}

static int dsp_buffer_free(struct cx23885_audio_dev *chip)
{
    BUG_ON(!chip->dma_size);

    dprintk(2, "Freeing buffer\n");
    videobuf_dma_unmap(&chip->pci->dev, chip->dma_risc);
    videobuf_dma_free(chip->dma_risc);
    btcx_riscmem_free(chip->pci, &chip->buf->risc);
    kfree(chip->buf);

    chip->dma_risc = NULL;
    chip->dma_size = 0;

    return 0;
}

/****************************************************************************
                ALSA PCM Interface
 ****************************************************************************/

/*
 * Digital hardware definition
 */
#define DEFAULT_FIFO_SIZE   4096

static struct snd_pcm_hardware snd_cx23885_digital_hw = {
    .info = SNDRV_PCM_INFO_MMAP |
        SNDRV_PCM_INFO_INTERLEAVED |
        SNDRV_PCM_INFO_BLOCK_TRANSFER |
        SNDRV_PCM_INFO_MMAP_VALID,
    .formats = SNDRV_PCM_FMTBIT_S16_LE,

    .rates =        SNDRV_PCM_RATE_48000,
    .rate_min =     48000,
    .rate_max =     48000,
    .channels_min = 2,
    .channels_max = 2,
    /* Analog audio output will be full of clicks and pops if there
       are not exactly four lines in the SRAM FIFO buffer.  */
    .period_bytes_min = DEFAULT_FIFO_SIZE/4,
    .period_bytes_max = DEFAULT_FIFO_SIZE/4,
    .periods_min = 1,
    .periods_max = 1024,
    .buffer_bytes_max = (1024*1024),
};

/*
 * audio pcm capture open callback
 */
static int snd_cx23885_pcm_open(struct snd_pcm_substream *substream)
{
    struct cx23885_audio_dev *chip = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err;

    if (!chip) {
        printk(KERN_ERR "BUG: cx23885 can't find device struct."
                " Can't proceed with open\n");
        return -ENODEV;
    }

    err = snd_pcm_hw_constraint_pow2(runtime, 0,
        SNDRV_PCM_HW_PARAM_PERIODS);
    if (err < 0)
        goto _error;

    chip->substream = substream;

    runtime->hw = snd_cx23885_digital_hw;

    if (chip->dev->sram_channels[AUDIO_SRAM_CHANNEL].fifo_size !=
        DEFAULT_FIFO_SIZE) {
        unsigned int bpl = chip->dev->
            sram_channels[AUDIO_SRAM_CHANNEL].fifo_size / 4;
        bpl &= ~7; /* must be multiple of 8 */
        runtime->hw.period_bytes_min = bpl;
        runtime->hw.period_bytes_max = bpl;
    }

    return 0;
_error:
    dprintk(1, "Error opening PCM!\n");
    return err;
}

/*
 * audio close callback
 */
static int snd_cx23885_close(struct snd_pcm_substream *substream)
{
    return 0;
}

/*
 * hw_params callback
 */
static int snd_cx23885_hw_params(struct snd_pcm_substream *substream,
                  struct snd_pcm_hw_params *hw_params)
{
    struct cx23885_audio_dev *chip = snd_pcm_substream_chip(substream);
    struct videobuf_dmabuf *dma;

    struct cx23885_audio_buffer *buf;
    int ret;

    if (substream->runtime->dma_area) {
        dsp_buffer_free(chip);
        substream->runtime->dma_area = NULL;
    }

    chip->period_size = params_period_bytes(hw_params);
    chip->num_periods = params_periods(hw_params);
    chip->dma_size = chip->period_size * params_periods(hw_params);

    BUG_ON(!chip->dma_size);
    BUG_ON(chip->num_periods & (chip->num_periods-1));

    buf = kzalloc(sizeof(*buf), GFP_KERNEL);
    if (NULL == buf)
        return -ENOMEM;

    buf->bpl = chip->period_size;

    dma = &buf->dma;
    videobuf_dma_init(dma);
    ret = videobuf_dma_init_kernel(dma, PCI_DMA_FROMDEVICE,
            (PAGE_ALIGN(chip->dma_size) >> PAGE_SHIFT));
    if (ret < 0)
        goto error;

    ret = videobuf_dma_map(&chip->pci->dev, dma);
    if (ret < 0)
        goto error;

    ret = cx23885_risc_databuffer(chip->pci, &buf->risc, dma->sglist,
                   chip->period_size, chip->num_periods, 1);
    if (ret < 0)
        goto error;

    /* Loop back to start of program */
    buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP|RISC_IRQ1|RISC_CNT_INC);
    buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma);
    buf->risc.jmp[2] = cpu_to_le32(0); /* bits 63-32 */

    chip->buf = buf;
    chip->dma_risc = dma;

    substream->runtime->dma_area = chip->dma_risc->vaddr;
    substream->runtime->dma_bytes = chip->dma_size;
    substream->runtime->dma_addr = 0;

    return 0;

error:
    kfree(buf);
    return ret;
}

/*
 * hw free callback
 */
static int snd_cx23885_hw_free(struct snd_pcm_substream *substream)
{

    struct cx23885_audio_dev *chip = snd_pcm_substream_chip(substream);

    if (substream->runtime->dma_area) {
        dsp_buffer_free(chip);
        substream->runtime->dma_area = NULL;
    }

    return 0;
}

/*
 * prepare callback
 */
static int snd_cx23885_prepare(struct snd_pcm_substream *substream)
{
    return 0;
}

/*
 * trigger callback
 */
static int snd_cx23885_card_trigger(struct snd_pcm_substream *substream,
    int cmd)
{
    struct cx23885_audio_dev *chip = snd_pcm_substream_chip(substream);
    int err;

    /* Local interrupts are already disabled by ALSA */
    spin_lock(&chip->lock);

    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
        err = cx23885_start_audio_dma(chip);
        break;
    case SNDRV_PCM_TRIGGER_STOP:
        err = cx23885_stop_audio_dma(chip);
        break;
    default:
        err = -EINVAL;
        break;
    }

    spin_unlock(&chip->lock);

    return err;
}

/*
 * pointer callback
 */
static snd_pcm_uframes_t snd_cx23885_pointer(
    struct snd_pcm_substream *substream)
{
    struct cx23885_audio_dev *chip = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    u16 count;

    count = atomic_read(&chip->count);

    return runtime->period_size * (count & (runtime->periods-1));
}

/*
 * page callback (needed for mmap)
 */
static struct page *snd_cx23885_page(struct snd_pcm_substream *substream,
                unsigned long offset)
{
    void *pageptr = substream->runtime->dma_area + offset;
    return vmalloc_to_page(pageptr);
}

/*
 * operators
 */
static struct snd_pcm_ops snd_cx23885_pcm_ops = {
    .open = snd_cx23885_pcm_open,
    .close = snd_cx23885_close,
    .ioctl = snd_pcm_lib_ioctl,
    .hw_params = snd_cx23885_hw_params,
    .hw_free = snd_cx23885_hw_free,
    .prepare = snd_cx23885_prepare,
    .trigger = snd_cx23885_card_trigger,
    .pointer = snd_cx23885_pointer,
    .page = snd_cx23885_page,
};

/*
 * create a PCM device
 */
static int snd_cx23885_pcm(struct cx23885_audio_dev *chip, int device,
    char *name)
{
    int err;
    struct snd_pcm *pcm;

    err = snd_pcm_new(chip->card, name, device, 0, 1, &pcm);
    if (err < 0)
        return err;
    pcm->private_data = chip;
    strcpy(pcm->name, name);
    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_cx23885_pcm_ops);

    return 0;
}

/****************************************************************************
            Basic Flow for Sound Devices
 ****************************************************************************/

/*
 * Alsa Constructor - Component probe
 */

struct cx23885_audio_dev *cx23885_audio_register(struct cx23885_dev *dev)
{
    struct snd_card *card;
    struct cx23885_audio_dev *chip;
    int err;

    if (disable_analog_audio)
        return NULL;

    if (dev->sram_channels[AUDIO_SRAM_CHANNEL].cmds_start == 0) {
        printk(KERN_WARNING "%s(): Missing SRAM channel configuration "
            "for analog TV Audio\n", __func__);
        return NULL;
    }

    err = snd_card_create(SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
            THIS_MODULE, sizeof(struct cx23885_audio_dev), &card);
    if (err < 0)
        goto error;

    chip = (struct cx23885_audio_dev *) card->private_data;
    chip->dev = dev;
    chip->pci = dev->pci;
    chip->card = card;
    spin_lock_init(&chip->lock);

    snd_card_set_dev(card, &dev->pci->dev);

    err = snd_cx23885_pcm(chip, 0, "CX23885 Digital");
    if (err < 0)
        goto error;

    strcpy(card->driver, "CX23885");
    sprintf(card->shortname, "Conexant CX23885");
    sprintf(card->longname, "%s at %s", card->shortname, dev->name);

    err = snd_card_register(card);
    if (err < 0)
        goto error;

    dprintk(0, "registered ALSA audio device\n");

    return chip;

error:
    snd_card_free(card);
    printk(KERN_ERR "%s(): Failed to register analog "
            "audio adapter\n", __func__);

    return NULL;
}

/*
 * ALSA destructor
 */
void cx23885_audio_unregister(struct cx23885_dev *dev)
{
    struct cx23885_audio_dev *chip = dev->audio_dev;

    snd_card_free(chip->card);
}