saa7134-alsa.c

linux-2.6.15.6

/*
 *   SAA713x ALSA support for V4L
 *
 *
 *   Caveats:
 *        - Volume doesn't work (it's always at max)
 *
 *   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, version 2
 *
 *   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 <sound/driver.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/wait.h>
#include <linux/moduleparam.h>
#include <linux/module.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/initval.h>
#include <linux/interrupt.h>

#include "saa7134.h"
#include "saa7134-reg.h"

static unsigned int debug  = 0;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug,"enable debug messages [alsa]");

/*
 * Configuration macros
 */

/* defaults */
#define MIXER_ADDR_TVTUNER	0
#define MIXER_ADDR_LINE1	1
#define MIXER_ADDR_LINE2	2
#define MIXER_ADDR_LAST		2


static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for SAA7134 capture interface(s).");

#define dprintk(fmt, arg...)    if (debug) \
	printk(KERN_DEBUG "%s/alsa: " fmt, dev->name , ##arg)



/*
 * Main chip structure
 */

typedef struct snd_card_saa7134 {
	snd_card_t *card;
	spinlock_t mixer_lock;
	int mixer_volume[MIXER_ADDR_LAST+1][2];
	int capture_source[MIXER_ADDR_LAST+1][2];
	struct pci_dev *pci;
	struct saa7134_dev *dev;

	unsigned long iobase;
	int irq;

	spinlock_t lock;
} snd_card_saa7134_t;



/*
 * PCM structure
 */

typedef struct snd_card_saa7134_pcm {
	struct saa7134_dev *dev;

	spinlock_t lock;

	snd_pcm_substream_t *substream;
} snd_card_saa7134_pcm_t;

static snd_card_t *snd_saa7134_cards[SNDRV_CARDS];


/*
 * saa7134 DMA audio stop
 *
 *   Called when the capture device is released or the buffer overflows
 *
 *   - Copied verbatim from saa7134-oss's dsp_dma_stop.
 *
 */

static void saa7134_dma_stop(struct saa7134_dev *dev)
{
	dev->dmasound.dma_blk     = -1;
	dev->dmasound.dma_running = 0;
	saa7134_set_dmabits(dev);
}

/*
 * saa7134 DMA audio start
 *
 *   Called when preparing the capture device for use
 *
 *   - Copied verbatim from saa7134-oss's dsp_dma_start.
 *
 */

static void saa7134_dma_start(struct saa7134_dev *dev)
{
	dev->dmasound.dma_blk     = 0;
	dev->dmasound.dma_running = 1;
	saa7134_set_dmabits(dev);
}

/*
 * saa7134 audio DMA IRQ handler
 *
 *   Called whenever we get an SAA7134_IRQ_REPORT_DONE_RA3 interrupt
 *   Handles shifting between the 2 buffers, manages the read counters,
 *  and notifies ALSA when periods elapse
 *
 *   - Mostly copied from saa7134-oss's saa7134_irq_oss_done.
 *
 */

static void saa7134_irq_alsa_done(struct saa7134_dev *dev,
				  unsigned long status)
{
	int next_blk, reg = 0;

	spin_lock(&dev->slock);
	if (UNSET == dev->dmasound.dma_blk) {
		dprintk("irq: recording stopped\n");
		goto done;
	}
	if (0 != (status & 0x0f000000))
		dprintk("irq: lost %ld\n", (status >> 24) & 0x0f);
	if (0 == (status & 0x10000000)) {
		/* odd */
		if (0 == (dev->dmasound.dma_blk & 0x01))
			reg = SAA7134_RS_BA1(6);
	} else {
		/* even */
		if (1 == (dev->dmasound.dma_blk & 0x01))
			reg = SAA7134_RS_BA2(6);
	}
	if (0 == reg) {
		dprintk("irq: field oops [%s]\n",
			(status & 0x10000000) ? "even" : "odd");
		goto done;
	}

	if (dev->dmasound.read_count >= dev->dmasound.blksize * (dev->dmasound.blocks-2)) {
		dprintk("irq: overrun [full=%d/%d] - Blocks in %d\n",dev->dmasound.read_count,
			dev->dmasound.bufsize, dev->dmasound.blocks);
		spin_unlock(&dev->slock);
		snd_pcm_stop(dev->dmasound.substream,SNDRV_PCM_STATE_XRUN);
		return;
	}

	/* next block addr */
	next_blk = (dev->dmasound.dma_blk + 2) % dev->dmasound.blocks;
	saa_writel(reg,next_blk * dev->dmasound.blksize);
	if (debug > 2)
		dprintk("irq: ok, %s, next_blk=%d, addr=%x, blocks=%u, size=%u, read=%u\n",
			(status & 0x10000000) ? "even" : "odd ", next_blk,
			next_blk * dev->dmasound.blksize, dev->dmasound.blocks, dev->dmasound.blksize, dev->dmasound.read_count);

	/* update status & wake waiting readers */
	dev->dmasound.dma_blk = (dev->dmasound.dma_blk + 1) % dev->dmasound.blocks;
	dev->dmasound.read_count += dev->dmasound.blksize;

	dev->dmasound.recording_on = reg;

	if (dev->dmasound.read_count >= snd_pcm_lib_period_bytes(dev->dmasound.substream)) {
		spin_unlock(&dev->slock);
		snd_pcm_period_elapsed(dev->dmasound.substream);
		spin_lock(&dev->slock);
	}

 done:
	spin_unlock(&dev->slock);

}

/*
 * IRQ request handler
 *
 *   Runs along with saa7134's IRQ handler, discards anything that isn't
 *   DMA sound
 *
 */

static irqreturn_t saa7134_alsa_irq(int irq, void *dev_id, struct pt_regs *regs)
{
	struct saa7134_dmasound *dmasound = dev_id;
	struct saa7134_dev *dev = dmasound->priv_data;

	unsigned long report, status;
	int loop, handled = 0;

	for (loop = 0; loop < 10; loop++) {
		report = saa_readl(SAA7134_IRQ_REPORT);
		status = saa_readl(SAA7134_IRQ_STATUS);

		if (report & SAA7134_IRQ_REPORT_DONE_RA3) {
			handled = 1;
			saa_writel(SAA7134_IRQ_REPORT,report);
			saa7134_irq_alsa_done(dev, status);
		} else {
			goto out;
		}
	}

	if (loop == 10) {
		dprintk("error! looping IRQ!");
	}

out:
	return IRQ_RETVAL(handled);
}

/*
 * ALSA capture trigger
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called whenever a capture is started or stopped. Must be defined,
 *   but there's nothing we want to do here
 *
 */

static int snd_card_saa7134_capture_trigger(snd_pcm_substream_t * substream,
					  int cmd)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_saa7134_pcm_t *pcm = runtime->private_data;
	struct saa7134_dev *dev=pcm->dev;
	int err = 0;

	spin_lock(&dev->slock);
	if (cmd == SNDRV_PCM_TRIGGER_START) {
		/* start dma */
		saa7134_dma_start(dev);
	} else if (cmd == SNDRV_PCM_TRIGGER_STOP) {
		/* stop dma */
		saa7134_dma_stop(dev);
	} else {
		err = -EINVAL;
	}
	spin_unlock(&dev->slock);

	return err;
}

/*
 * DMA buffer initialization
 *
 *   Uses V4L functions to initialize the DMA. Shouldn't be necessary in
 *  ALSA, but I was unable to use ALSA's own DMA, and had to force the
 *  usage of V4L's
 *
 *   - Copied verbatim from saa7134-oss.
 *
 */

static int dsp_buffer_init(struct saa7134_dev *dev)
{
	int err;

	BUG_ON(!dev->dmasound.bufsize);

	videobuf_dma_init(&dev->dmasound.dma);
	err = videobuf_dma_init_kernel(&dev->dmasound.dma, PCI_DMA_FROMDEVICE,
				       (dev->dmasound.bufsize + PAGE_SIZE) >> PAGE_SHIFT);
	if (0 != err)
		return err;
	return 0;
}

/*
 * DMA buffer release
 *
 *   Called after closing the device, during snd_card_saa7134_capture_close
 *
 */

static int dsp_buffer_free(struct saa7134_dev *dev)
{
	if (!dev->dmasound.blksize)
		BUG();

	videobuf_dma_free(&dev->dmasound.dma);

	dev->dmasound.blocks  = 0;
	dev->dmasound.blksize = 0;
	dev->dmasound.bufsize = 0;

       return 0;
}


/*
 * ALSA PCM preparation
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called right after the capture device is opened, this function configures
 *  the buffer using the previously defined functions, allocates the memory,
 *  sets up the hardware registers, and then starts the DMA. When this function
 *  returns, the audio should be flowing.
 *
 */

static int snd_card_saa7134_capture_prepare(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	int bswap, sign;
	u32 fmt, control;
	snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
	struct saa7134_dev *dev;
	snd_card_saa7134_pcm_t *pcm = runtime->private_data;

	pcm->dev->dmasound.substream = substream;

	dev = saa7134->dev;

	if (snd_pcm_format_width(runtime->format) == 8)
		fmt = 0x00;
	else
		fmt = 0x01;

	if (snd_pcm_format_signed(runtime->format))
		sign = 1;
	else
		sign = 0;

	if (snd_pcm_format_big_endian(runtime->format))
		bswap = 1;
	else
		bswap = 0;

	switch (dev->pci->device) {
	  case PCI_DEVICE_ID_PHILIPS_SAA7134:
		if (1 == runtime->channels)
			fmt |= (1 << 3);
		if (2 == runtime->channels)
			fmt |= (3 << 3);
		if (sign)
			fmt |= 0x04;

		fmt |= (MIXER_ADDR_TVTUNER == dev->dmasound.input) ? 0xc0 : 0x80;
		saa_writeb(SAA7134_NUM_SAMPLES0, ((dev->dmasound.blksize - 1) & 0x0000ff));
		saa_writeb(SAA7134_NUM_SAMPLES1, ((dev->dmasound.blksize - 1) & 0x00ff00) >>  8);
		saa_writeb(SAA7134_NUM_SAMPLES2, ((dev->dmasound.blksize - 1) & 0xff0000) >> 16);
		saa_writeb(SAA7134_AUDIO_FORMAT_CTRL, fmt);

		break;
	  case PCI_DEVICE_ID_PHILIPS_SAA7133:
	  case PCI_DEVICE_ID_PHILIPS_SAA7135:
		if (1 == runtime->channels)
			fmt |= (1 << 4);
		if (2 == runtime->channels)
			fmt |= (2 << 4);
		if (!sign)
			fmt |= 0x04;
		saa_writel(SAA7133_NUM_SAMPLES, dev->dmasound.blksize -1);
		saa_writel(SAA7133_AUDIO_CHANNEL, 0x543210 | (fmt << 24));
		break;
	}

	dprintk("rec_start: afmt=%d ch=%d  =>  fmt=0x%x swap=%c\n",
		runtime->format, runtime->channels, fmt,
		bswap ? 'b' : '-');
	/* dma: setup channel 6 (= AUDIO) */
	control = SAA7134_RS_CONTROL_BURST_16 |
		SAA7134_RS_CONTROL_ME |
		(dev->dmasound.pt.dma >> 12);
	if (bswap)
		control |= SAA7134_RS_CONTROL_BSWAP;

	saa_writel(SAA7134_RS_BA1(6),0);
	saa_writel(SAA7134_RS_BA2(6),dev->dmasound.blksize);
	saa_writel(SAA7134_RS_PITCH(6),0);
	saa_writel(SAA7134_RS_CONTROL(6),control);

	dev->dmasound.rate = runtime->rate;

	return 0;

}

/*
 * ALSA pointer fetching
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called whenever a period elapses, it must return the current hardware
 *  position of the buffer.
 *   Also resets the read counter used to prevent overruns
 *
 */

static snd_pcm_uframes_t snd_card_saa7134_capture_pointer(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_saa7134_pcm_t *pcm = runtime->private_data;
	struct saa7134_dev *dev=pcm->dev;

	if (dev->dmasound.read_count) {
		dev->dmasound.read_count  -= snd_pcm_lib_period_bytes(substream);
		dev->dmasound.read_offset += snd_pcm_lib_period_bytes(substream);
		if (dev->dmasound.read_offset == dev->dmasound.bufsize)
			dev->dmasound.read_offset = 0;
	}

	return bytes_to_frames(runtime, dev->dmasound.read_offset);
}

/*
 * ALSA hardware capabilities definition
 */

static snd_pcm_hardware_t snd_card_saa7134_capture =
{
	.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 | \
				SNDRV_PCM_FMTBIT_S16_BE | \
				SNDRV_PCM_FMTBIT_S8 | \
				SNDRV_PCM_FMTBIT_U8 | \
				SNDRV_PCM_FMTBIT_U16_LE | \
				SNDRV_PCM_FMTBIT_U16_BE,
	.rates =		SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_48000,
	.rate_min =		32000,
	.rate_max =		48000,
	.channels_min =		1,
	.channels_max =		2,
	.buffer_bytes_max =	(256*1024),
	.period_bytes_min =	64,
	.period_bytes_max =	(256*1024),
	.periods_min =		2,
	.periods_max =		1024,
};

static void snd_card_saa7134_runtime_free(snd_pcm_runtime_t *runtime)
{
	snd_card_saa7134_pcm_t *pcm = runtime->private_data;

	kfree(pcm);
}


/*
 * ALSA hardware params
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called on initialization, right before the PCM preparation
 *
 */

static int snd_card_saa7134_hw_params(snd_pcm_substream_t * substream,
				    snd_pcm_hw_params_t * hw_params)
{
	snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
	struct saa7134_dev *dev;
	unsigned int period_size, periods;
	int err;

	period_size = params_period_bytes(hw_params);
	periods = params_periods(hw_params);

	snd_assert(period_size >= 0x100 && period_size <= 0x10000,
		   return -EINVAL);
	snd_assert(periods >= 2, return -EINVAL);
	snd_assert(period_size * periods <= 1024 * 1024, return -EINVAL);

	dev = saa7134->dev;

	if (dev->dmasound.blocks == periods &&
	    dev->dmasound.blksize == period_size)
		return 0;

	/* release the old buffer */
	if (substream->runtime->dma_area) {
		saa7134_pgtable_free(dev->pci, &dev->dmasound.pt);
		videobuf_dma_pci_unmap(dev->pci, &dev->dmasound.dma);
		dsp_buffer_free(dev);
		substream->runtime->dma_area = NULL;
	}
	dev->dmasound.blocks  = periods;
	dev->dmasound.blksize = period_size;
	dev->dmasound.bufsize = period_size * periods;

	err = dsp_buffer_init(dev);
	if (0 != err) {
		dev->dmasound.blocks  = 0;
		dev->dmasound.blksize = 0;
		dev->dmasound.bufsize = 0;
		return err;
	}