Initial import

1 files changed, 364 insertions, 0 deletions

diff --git a/drivers/media/pci/ivtv/ivtv-alsa-pcm.c b/drivers/media/pci/ivtv/ivtv-alsa-pcm.c
new file mode 100644
index 000000000..f198b9826
--- /dev/null
+++ b/drivers/media/pci/ivtv/ivtv-alsa-pcm.c
@@ -0,0 +1,364 @@
+/*
+ *  ALSA PCM device for the
+ *  ALSA interface to ivtv PCM capture streams
+ *
+ *  Copyright (C) 2009,2012  Andy Walls <awalls@md.metrocast.net>
+ *  Copyright (C) 2009  Devin Heitmueller <dheitmueller@kernellabs.com>
+ *
+ *  Portions of this work were sponsored by ONELAN Limited for the cx18 driver
+ *
+ *  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 <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/vmalloc.h>
+
+#include <media/v4l2-device.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+
+#include "ivtv-driver.h"
+#include "ivtv-queue.h"
+#include "ivtv-streams.h"
+#include "ivtv-fileops.h"
+#include "ivtv-alsa.h"
+#include "ivtv-alsa-pcm.h"
+
+static unsigned int pcm_debug;
+module_param(pcm_debug, int, 0644);
+MODULE_PARM_DESC(pcm_debug, "enable debug messages for pcm");
+
+#define dprintk(fmt, arg...) \
+	do { \
+		if (pcm_debug) \
+			pr_info("ivtv-alsa-pcm %s: " fmt, __func__, ##arg); \
+	} while (0)
+
+static struct snd_pcm_hardware snd_ivtv_hw_capture = {
+	.info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
+		SNDRV_PCM_INFO_MMAP           |
+		SNDRV_PCM_INFO_INTERLEAVED    |
+		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,
+	.buffer_bytes_max = 62720 * 8,	/* just about the value in usbaudio.c */
+	.period_bytes_min = 64,		/* 12544/2, */
+	.period_bytes_max = 12544,
+	.periods_min = 2,
+	.periods_max = 98,		/* 12544, */
+};
+
+static void ivtv_alsa_announce_pcm_data(struct snd_ivtv_card *itvsc,
+					u8 *pcm_data,
+					size_t num_bytes)
+{
+	struct snd_pcm_substream *substream;
+	struct snd_pcm_runtime *runtime;
+	unsigned int oldptr;
+	unsigned int stride;
+	int period_elapsed = 0;
+	int length;
+
+	dprintk("ivtv alsa announce ptr=%p data=%p num_bytes=%zu\n", itvsc,
+		pcm_data, num_bytes);
+
+	substream = itvsc->capture_pcm_substream;
+	if (substream == NULL) {
+		dprintk("substream was NULL\n");
+		return;
+	}
+
+	runtime = substream->runtime;
+	if (runtime == NULL) {
+		dprintk("runtime was NULL\n");
+		return;
+	}
+
+	stride = runtime->frame_bits >> 3;
+	if (stride == 0) {
+		dprintk("stride is zero\n");
+		return;
+	}
+
+	length = num_bytes / stride;
+	if (length == 0) {
+		dprintk("%s: length was zero\n", __func__);
+		return;
+	}
+
+	if (runtime->dma_area == NULL) {
+		dprintk("dma area was NULL - ignoring\n");
+		return;
+	}
+
+	oldptr = itvsc->hwptr_done_capture;
+	if (oldptr + length >= runtime->buffer_size) {
+		unsigned int cnt =
+			runtime->buffer_size - oldptr;
+		memcpy(runtime->dma_area + oldptr * stride, pcm_data,
+		       cnt * stride);
+		memcpy(runtime->dma_area, pcm_data + cnt * stride,
+		       length * stride - cnt * stride);
+	} else {
+		memcpy(runtime->dma_area + oldptr * stride, pcm_data,
+		       length * stride);
+	}
+	snd_pcm_stream_lock(substream);
+
+	itvsc->hwptr_done_capture += length;
+	if (itvsc->hwptr_done_capture >=
+	    runtime->buffer_size)
+		itvsc->hwptr_done_capture -=
+			runtime->buffer_size;
+
+	itvsc->capture_transfer_done += length;
+	if (itvsc->capture_transfer_done >=
+	    runtime->period_size) {
+		itvsc->capture_transfer_done -=
+			runtime->period_size;
+		period_elapsed = 1;
+	}
+
+	snd_pcm_stream_unlock(substream);
+
+	if (period_elapsed)
+		snd_pcm_period_elapsed(substream);
+}
+
+static int snd_ivtv_pcm_capture_open(struct snd_pcm_substream *substream)
+{
+	struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct v4l2_device *v4l2_dev = itvsc->v4l2_dev;
+	struct ivtv *itv = to_ivtv(v4l2_dev);
+	struct ivtv_stream *s;
+	struct ivtv_open_id item;
+	int ret;
+
+	/* Instruct the CX2341[56] to start sending packets */
+	snd_ivtv_lock(itvsc);
+
+	if (ivtv_init_on_first_open(itv)) {
+		snd_ivtv_unlock(itvsc);
+		return -ENXIO;
+	}
+
+	s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
+
+	v4l2_fh_init(&item.fh, &s->vdev);
+	item.itv = itv;
+	item.type = s->type;
+
+	/* See if the stream is available */
+	if (ivtv_claim_stream(&item, item.type)) {
+		/* No, it's already in use */
+		snd_ivtv_unlock(itvsc);
+		return -EBUSY;
+	}
+
+	if (test_bit(IVTV_F_S_STREAMOFF, &s->s_flags) ||
+	    test_and_set_bit(IVTV_F_S_STREAMING, &s->s_flags)) {
+		/* We're already streaming.  No additional action required */
+		snd_ivtv_unlock(itvsc);
+		return 0;
+	}
+
+
+	runtime->hw = snd_ivtv_hw_capture;
+	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
+	itvsc->capture_pcm_substream = substream;
+	runtime->private_data = itv;
+
+	itv->pcm_announce_callback = ivtv_alsa_announce_pcm_data;
+
+	/* Not currently streaming, so start it up */
+	set_bit(IVTV_F_S_STREAMING, &s->s_flags);
+	ret = ivtv_start_v4l2_encode_stream(s);
+	snd_ivtv_unlock(itvsc);
+
+	return ret;
+}
+
+static int snd_ivtv_pcm_capture_close(struct snd_pcm_substream *substream)
+{
+	struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);
+	struct v4l2_device *v4l2_dev = itvsc->v4l2_dev;
+	struct ivtv *itv = to_ivtv(v4l2_dev);
+	struct ivtv_stream *s;
+
+	/* Instruct the ivtv to stop sending packets */
+	snd_ivtv_lock(itvsc);
+	s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
+	ivtv_stop_v4l2_encode_stream(s, 0);
+	clear_bit(IVTV_F_S_STREAMING, &s->s_flags);
+
+	ivtv_release_stream(s);
+
+	itv->pcm_announce_callback = NULL;
+	snd_ivtv_unlock(itvsc);
+
+	return 0;
+}
+
+static int snd_ivtv_pcm_ioctl(struct snd_pcm_substream *substream,
+		     unsigned int cmd, void *arg)
+{
+	struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);
+	int ret;
+
+	snd_ivtv_lock(itvsc);
+	ret = snd_pcm_lib_ioctl(substream, cmd, arg);
+	snd_ivtv_unlock(itvsc);
+	return ret;
+}
+
+
+static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
+					size_t size)
+{
+	struct snd_pcm_runtime *runtime = subs->runtime;
+
+	dprintk("Allocating vbuffer\n");
+	if (runtime->dma_area) {
+		if (runtime->dma_bytes > size)
+			return 0;
+
+		vfree(runtime->dma_area);
+	}
+	runtime->dma_area = vmalloc(size);
+	if (!runtime->dma_area)
+		return -ENOMEM;
+
+	runtime->dma_bytes = size;
+
+	return 0;
+}
+
+static int snd_ivtv_pcm_hw_params(struct snd_pcm_substream *substream,
+			 struct snd_pcm_hw_params *params)
+{
+	dprintk("%s called\n", __func__);
+
+	return snd_pcm_alloc_vmalloc_buffer(substream,
+					   params_buffer_bytes(params));
+}
+
+static int snd_ivtv_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);
+	unsigned long flags;
+
+	spin_lock_irqsave(&itvsc->slock, flags);
+	if (substream->runtime->dma_area) {
+		dprintk("freeing pcm capture region\n");
+		vfree(substream->runtime->dma_area);
+		substream->runtime->dma_area = NULL;
+	}
+	spin_unlock_irqrestore(&itvsc->slock, flags);
+
+	return 0;
+}
+
+static int snd_ivtv_pcm_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);
+
+	itvsc->hwptr_done_capture = 0;
+	itvsc->capture_transfer_done = 0;
+
+	return 0;
+}
+
+static int snd_ivtv_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	return 0;
+}
+
+static
+snd_pcm_uframes_t snd_ivtv_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	unsigned long flags;
+	snd_pcm_uframes_t hwptr_done;
+	struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);
+
+	spin_lock_irqsave(&itvsc->slock, flags);
+	hwptr_done = itvsc->hwptr_done_capture;
+	spin_unlock_irqrestore(&itvsc->slock, flags);
+
+	return hwptr_done;
+}
+
+static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
+					     unsigned long offset)
+{
+	void *pageptr = subs->runtime->dma_area + offset;
+
+	return vmalloc_to_page(pageptr);
+}
+
+static struct snd_pcm_ops snd_ivtv_pcm_capture_ops = {
+	.open		= snd_ivtv_pcm_capture_open,
+	.close		= snd_ivtv_pcm_capture_close,
+	.ioctl		= snd_ivtv_pcm_ioctl,
+	.hw_params	= snd_ivtv_pcm_hw_params,
+	.hw_free	= snd_ivtv_pcm_hw_free,
+	.prepare	= snd_ivtv_pcm_prepare,
+	.trigger	= snd_ivtv_pcm_trigger,
+	.pointer	= snd_ivtv_pcm_pointer,
+	.page		= snd_pcm_get_vmalloc_page,
+};
+
+int snd_ivtv_pcm_create(struct snd_ivtv_card *itvsc)
+{
+	struct snd_pcm *sp;
+	struct snd_card *sc = itvsc->sc;
+	struct v4l2_device *v4l2_dev = itvsc->v4l2_dev;
+	struct ivtv *itv = to_ivtv(v4l2_dev);
+	int ret;
+
+	ret = snd_pcm_new(sc, "CX2341[56] PCM",
+			  0, /* PCM device 0, the only one for this card */
+			  0, /* 0 playback substreams */
+			  1, /* 1 capture substream */
+			  &sp);
+	if (ret) {
+		IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",
+			      __func__, ret);
+		goto err_exit;
+	}
+
+	spin_lock_init(&itvsc->slock);
+
+	snd_pcm_set_ops(sp, SNDRV_PCM_STREAM_CAPTURE,
+			&snd_ivtv_pcm_capture_ops);
+	sp->info_flags = 0;
+	sp->private_data = itvsc;
+	strlcpy(sp->name, itv->card_name, sizeof(sp->name));
+
+	return 0;
+
+err_exit:
+	return ret;
+}