1 files changed, 427 insertions, 0 deletions
diff --git a/drivers/staging/line6/playback.c b/drivers/staging/line6/playback.c
new file mode 100644
index 000000000000..acb06126a6a5
--- /dev/null
+++ b/drivers/staging/line6/playback.c
@@ -0,0 +1,427 @@
+/*
+ * Line6 Linux USB driver - 0.8.0
+ *
+ * Copyright (C) 2004-2009 Markus Grabner (grabner@icg.tugraz.at)
+ *
+ *	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.
+ *
+ */
+
+#include "driver.h"
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include "audio.h"
+#include "pcm.h"
+#include "pod.h"
+#include "playback.h"
+
+
+/*
+	Software stereo volume control.
+*/
+static void change_volume(struct urb *urb_out, int volume[],
+			  int bytes_per_frame)
+{
+	int chn = 0;
+
+	if (volume[0] == 256 && volume[1] == 256)
+		return;  /* maximum volume - no change */
+
+	if (bytes_per_frame == 4) {
+		short *p, *buf_end;
+		p = (short *)urb_out->transfer_buffer;
+		buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
+
+		for (; p < buf_end; ++p) {
+			*p = (*p * volume[chn & 1]) >> 8;
+			++chn;
+		}
+	} else if (bytes_per_frame == 6) {
+		unsigned char *p, *buf_end;
+		p = (unsigned char *)urb_out->transfer_buffer;
+		buf_end = p + urb_out->transfer_buffer_length;
+
+		for (; p < buf_end; p += 3) {
+			int val;
+			val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16);
+			val = (val * volume[chn & 1]) >> 8;
+			p[0] = val;
+			p[1] = val >> 8;
+			p[2] = val >> 16;
+			++chn;
+		}
+	}
+}
+
+/*
+	Find a free URB, prepare audio data, and submit URB.
+*/
+static int submit_audio_out_urb(struct snd_pcm_substream *substream)
+{
+	int index;
+	unsigned long flags;
+	int i, urb_size, urb_frames;
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+	const int bytes_per_frame = line6pcm->properties->bytes_per_frame;
+	const int frame_increment = line6pcm->properties->snd_line6_rates.rats[0].num_min;
+	const int frame_factor = line6pcm->properties->snd_line6_rates.rats[0].den * (USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct urb *urb_out;
+
+	spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
+	index = find_first_zero_bit(&line6pcm->active_urb_out, LINE6_ISO_BUFFERS);
+
+	if (index < 0 || index >= LINE6_ISO_BUFFERS) {
+		spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
+		dev_err(s2m(substream), "no free URB found\n");
+		return -EINVAL;
+	}
+
+	urb_out = line6pcm->urb_audio_out[index];
+	urb_size = 0;
+
+	for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
+		/* compute frame size for given sampling rate */
+		int n, fs;
+		struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
+		line6pcm->count_out += frame_increment;
+		n = line6pcm->count_out / frame_factor;
+		line6pcm->count_out -= n * frame_factor;
+		fs = n * bytes_per_frame;
+		fout->offset = urb_size;
+		fout->length = fs;
+		urb_size += fs;
+	}
+
+	urb_frames = urb_size / bytes_per_frame;
+
+	if (test_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags)) {
+		urb_out->transfer_buffer = line6pcm->wrap_out;
+		memset(line6pcm->wrap_out, 0, urb_size);
+	} else {
+		if (line6pcm->pos_out + urb_frames > runtime->buffer_size) {
+			/*
+				The transferred area goes over buffer boundary,
+				copy the data to the temp buffer.
+			*/
+			int len;
+			len = runtime->buffer_size - line6pcm->pos_out;
+			urb_out->transfer_buffer = line6pcm->wrap_out;
+
+			if (len > 0) {
+				memcpy(line6pcm->wrap_out, runtime->dma_area + line6pcm->pos_out * bytes_per_frame, len * bytes_per_frame);
+				memcpy(line6pcm->wrap_out + len * bytes_per_frame, runtime->dma_area, (urb_frames - len) * bytes_per_frame);
+			} else
+				dev_err(s2m(substream), "driver bug: len = %d\n", len);  /* this is somewhat paranoid */
+		} else {
+			/* set the buffer pointer */
+			urb_out->transfer_buffer = runtime->dma_area + line6pcm->pos_out * bytes_per_frame;
+		}
+	}
+
+	if ((line6pcm->pos_out += urb_frames) >= runtime->buffer_size)
+		line6pcm->pos_out -= runtime->buffer_size;
+
+	urb_out->transfer_buffer_length = urb_size;
+	urb_out->context = substream;
+	change_volume(urb_out, line6pcm->volume, bytes_per_frame);
+
+#if DO_DUMP_PCM_SEND
+	for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
+		struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
+		line6_write_hexdump(line6pcm->line6, 'P', urb_out->transfer_buffer + fout->offset, fout->length);
+	}
+#endif
+
+	if (usb_submit_urb(urb_out, GFP_ATOMIC) == 0)
+		set_bit(index, &line6pcm->active_urb_out);
+	else
+		dev_err(s2m(substream), "URB out #%d submission failed\n", index);
+
+	spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
+	return 0;
+}
+
+/*
+	Submit all currently available playback URBs.
+*/
+static int submit_audio_out_all_urbs(struct snd_pcm_substream *substream)
+{
+	int ret, i;
+
+	for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
+		ret = submit_audio_out_urb(substream);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+/*
+	Unlink all currently active playback URBs.
+*/
+static void unlink_audio_out_urbs(struct snd_line6_pcm *line6pcm)
+{
+	unsigned int i;
+
+	for (i = LINE6_ISO_BUFFERS; i--;) {
+		if (test_bit(i, &line6pcm->active_urb_out)) {
+			if (!test_and_set_bit(i, &line6pcm->unlink_urb_out)) {
+				struct urb *u = line6pcm->urb_audio_out[i];
+				usb_unlink_urb(u);
+			}
+		}
+	}
+}
+
+/*
+	Wait until unlinking of all currently active playback URBs has been finished.
+*/
+static void wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
+{
+	int timeout = HZ;
+	unsigned int i;
+	int alive;
+
+	do {
+		alive = 0;
+		for (i = LINE6_ISO_BUFFERS; i--;) {
+			if (test_bit(i, &line6pcm->active_urb_out))
+				alive++;
+		}
+		if (!alive)
+			break;
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(1);
+	} while (--timeout > 0);
+	if (alive)
+		snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
+
+	line6pcm->active_urb_out = 0;
+	line6pcm->unlink_urb_out = 0;
+}
+
+/*
+	Unlink all currently active playback URBs, and wait for finishing.
+*/
+void unlink_wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
+{
+	unlink_audio_out_urbs(line6pcm);
+	wait_clear_audio_out_urbs(line6pcm);
+}
+
+/*
+	Callback for completed playback URB.
+*/
+static void audio_out_callback(struct urb *urb)
+{
+	int i, index, length = 0, shutdown = 0;
+	unsigned long flags;
+
+	struct snd_pcm_substream *substream = (struct snd_pcm_substream *)urb->context;
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	/* find index of URB */
+	for (index = LINE6_ISO_BUFFERS; index--;)
+		if (urb == line6pcm->urb_audio_out[index])
+			break;
+
+	if (index < 0)
+		return;  /* URB has been unlinked asynchronously */
+
+	for (i = LINE6_ISO_PACKETS; i--;)
+		length += urb->iso_frame_desc[i].length;
+
+	spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
+	line6pcm->pos_out_done += length / line6pcm->properties->bytes_per_frame;
+
+	if (line6pcm->pos_out_done >= runtime->buffer_size)
+		line6pcm->pos_out_done -= runtime->buffer_size;
+
+	clear_bit(index, &line6pcm->active_urb_out);
+
+	for (i = LINE6_ISO_PACKETS; i--;)
+		if (urb->iso_frame_desc[i].status == -ESHUTDOWN) {
+			shutdown = 1;
+			break;
+		}
+
+	if (test_bit(index, &line6pcm->unlink_urb_out))
+		shutdown = 1;
+
+	spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
+
+	if (!shutdown) {
+		submit_audio_out_urb(substream);
+
+		if ((line6pcm->bytes_out += length) >= line6pcm->period_out) {
+			line6pcm->bytes_out -= line6pcm->period_out;
+			snd_pcm_period_elapsed(substream);
+		}
+	}
+}
+
+/* open playback callback */
+static int snd_line6_playback_open(struct snd_pcm_substream *substream)
+{
+	int err;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+
+	err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+					    (&line6pcm->properties->snd_line6_rates));
+	if (err < 0)
+		return err;
+
+	runtime->hw = line6pcm->properties->snd_line6_playback_hw;
+	return 0;
+}
+
+/* close playback callback */
+static int snd_line6_playback_close(struct snd_pcm_substream *substream)
+{
+	return 0;
+}
+
+/* hw_params playback callback */
+static int snd_line6_playback_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *hw_params)
+{
+	int ret;
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+
+	/* -- Florian Demski [FD] */
+	/* don't ask me why, but this fixes the bug on my machine */
+	if (line6pcm == NULL) {
+		if (substream->pcm == NULL)
+			return -ENOMEM;
+		if (substream->pcm->private_data == NULL)
+			return -ENOMEM;
+		substream->private_data = substream->pcm->private_data;
+		line6pcm = snd_pcm_substream_chip(substream);
+	}
+	/* -- [FD] end */
+
+	ret = snd_pcm_lib_malloc_pages(substream,
+				       params_buffer_bytes(hw_params));
+	if (ret < 0)
+		return ret;
+
+	line6pcm->period_out = params_period_bytes(hw_params);
+	line6pcm->wrap_out = kmalloc(2 * LINE6_ISO_PACKET_SIZE_MAX, GFP_KERNEL);
+
+	if (!line6pcm->wrap_out) {
+		dev_err(s2m(substream), "cannot malloc wrap_out\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/* hw_free playback callback */
+static int snd_line6_playback_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+	unlink_wait_clear_audio_out_urbs(line6pcm);
+
+	kfree(line6pcm->wrap_out);
+	line6pcm->wrap_out = NULL;
+
+	return snd_pcm_lib_free_pages(substream);
+}
+
+/* trigger playback callback */
+int snd_line6_playback_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+	int err;
+	line6pcm->count_out = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		if (!test_and_set_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags)) {
+			err = submit_audio_out_all_urbs(substream);
+
+			if (err < 0) {
+				clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags);
+				return err;
+			}
+		}
+
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+		if (test_and_clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags))
+			unlink_audio_out_urbs(line6pcm);
+
+		break;
+
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		set_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
+		break;
+
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		clear_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* playback pointer callback */
+static snd_pcm_uframes_t
+snd_line6_playback_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+	return line6pcm->pos_out_done;
+}
+
+/* playback operators */
+struct snd_pcm_ops snd_line6_playback_ops = {
+	.open =        snd_line6_playback_open,
+	.close =       snd_line6_playback_close,
+	.ioctl =       snd_pcm_lib_ioctl,
+	.hw_params =   snd_line6_playback_hw_params,
+	.hw_free =     snd_line6_playback_hw_free,
+	.prepare =     snd_line6_prepare,
+	.trigger =     snd_line6_trigger,
+	.pointer =     snd_line6_playback_pointer,
+};
+
+int create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
+{
+	int i;
+
+	/* create audio URBs and fill in constant values: */
+	for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
+		struct urb *urb;
+
+		/* URB for audio out: */
+		urb = line6pcm->urb_audio_out[i] = usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
+
+		if (urb == NULL) {
+			dev_err(line6pcm->line6->ifcdev, "Out of memory\n");
+			return -ENOMEM;
+		}
+
+		urb->dev = line6pcm->line6->usbdev;
+		urb->pipe = usb_sndisocpipe(line6pcm->line6->usbdev, line6pcm->ep_audio_write & USB_ENDPOINT_NUMBER_MASK);
+		urb->transfer_flags = URB_ISO_ASAP;
+		urb->start_frame = -1;
+		urb->number_of_packets = LINE6_ISO_PACKETS;
+		urb->interval = LINE6_ISO_INTERVAL;
+		urb->error_count = 0;
+		urb->complete = audio_out_callback;
+	}
+
+	return 0;
+}