1 files changed, 299 insertions, 0 deletions
diff --git a/sound/usb/line6/capture.c b/sound/usb/line6/capture.c
new file mode 100644
index 000000000..8efd9f00c
--- /dev/null
+++ b/sound/usb/line6/capture.c
@@ -0,0 +1,299 @@
+/*
+ * Line 6 Linux USB driver
+ *
+ * Copyright (C) 2004-2010 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 <linux/slab.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include "capture.h"
+#include "driver.h"
+#include "pcm.h"
+
+/*
+	Find a free URB and submit it.
+	must be called in line6pcm->in.lock context
+*/
+static int submit_audio_in_urb(struct snd_line6_pcm *line6pcm)
+{
+	int index;
+	int i, urb_size;
+	int ret;
+	struct urb *urb_in;
+
+	index = find_first_zero_bit(&line6pcm->in.active_urbs,
+				    line6pcm->line6->iso_buffers);
+
+	if (index < 0 || index >= line6pcm->line6->iso_buffers) {
+		dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
+		return -EINVAL;
+	}
+
+	urb_in = line6pcm->in.urbs[index];
+	urb_size = 0;
+
+	for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
+		struct usb_iso_packet_descriptor *fin =
+		    &urb_in->iso_frame_desc[i];
+		fin->offset = urb_size;
+		fin->length = line6pcm->max_packet_size_in;
+		urb_size += line6pcm->max_packet_size_in;
+	}
+
+	urb_in->transfer_buffer =
+	    line6pcm->in.buffer +
+	    index * LINE6_ISO_PACKETS * line6pcm->max_packet_size_in;
+	urb_in->transfer_buffer_length = urb_size;
+	urb_in->context = line6pcm;
+
+	ret = usb_submit_urb(urb_in, GFP_ATOMIC);
+
+	if (ret == 0)
+		set_bit(index, &line6pcm->in.active_urbs);
+	else
+		dev_err(line6pcm->line6->ifcdev,
+			"URB in #%d submission failed (%d)\n", index, ret);
+
+	return 0;
+}
+
+/*
+	Submit all currently available capture URBs.
+	must be called in line6pcm->in.lock context
+*/
+int line6_submit_audio_in_all_urbs(struct snd_line6_pcm *line6pcm)
+{
+	int ret = 0, i;
+
+	for (i = 0; i < line6pcm->line6->iso_buffers; ++i) {
+		ret = submit_audio_in_urb(line6pcm);
+		if (ret < 0)
+			break;
+	}
+
+	return ret;
+}
+
+/*
+	Copy data into ALSA capture buffer.
+*/
+void line6_capture_copy(struct snd_line6_pcm *line6pcm, char *fbuf, int fsize)
+{
+	struct snd_pcm_substream *substream =
+	    get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	const int bytes_per_frame =
+		line6pcm->properties->bytes_per_channel *
+		line6pcm->properties->capture_hw.channels_max;
+	int frames = fsize / bytes_per_frame;
+
+	if (runtime == NULL)
+		return;
+
+	if (line6pcm->in.pos_done + frames > runtime->buffer_size) {
+		/*
+		   The transferred area goes over buffer boundary,
+		   copy two separate chunks.
+		 */
+		int len;
+
+		len = runtime->buffer_size - line6pcm->in.pos_done;
+
+		if (len > 0) {
+			memcpy(runtime->dma_area +
+			       line6pcm->in.pos_done * bytes_per_frame, fbuf,
+			       len * bytes_per_frame);
+			memcpy(runtime->dma_area, fbuf + len * bytes_per_frame,
+			       (frames - len) * bytes_per_frame);
+		} else {
+			/* this is somewhat paranoid */
+			dev_err(line6pcm->line6->ifcdev,
+				"driver bug: len = %d\n", len);
+		}
+	} else {
+		/* copy single chunk */
+		memcpy(runtime->dma_area +
+		       line6pcm->in.pos_done * bytes_per_frame, fbuf, fsize);
+	}
+
+	line6pcm->in.pos_done += frames;
+	if (line6pcm->in.pos_done >= runtime->buffer_size)
+		line6pcm->in.pos_done -= runtime->buffer_size;
+}
+
+void line6_capture_check_period(struct snd_line6_pcm *line6pcm, int length)
+{
+	struct snd_pcm_substream *substream =
+	    get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
+
+	line6pcm->in.bytes += length;
+	if (line6pcm->in.bytes >= line6pcm->in.period) {
+		line6pcm->in.bytes %= line6pcm->in.period;
+		spin_unlock(&line6pcm->in.lock);
+		snd_pcm_period_elapsed(substream);
+		spin_lock(&line6pcm->in.lock);
+	}
+}
+
+/*
+ * Callback for completed capture URB.
+ */
+static void audio_in_callback(struct urb *urb)
+{
+	int i, index, length = 0, shutdown = 0;
+	unsigned long flags;
+
+	struct snd_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context;
+
+	line6pcm->in.last_frame = urb->start_frame;
+
+	/* find index of URB */
+	for (index = 0; index < line6pcm->line6->iso_buffers; ++index)
+		if (urb == line6pcm->in.urbs[index])
+			break;
+
+	spin_lock_irqsave(&line6pcm->in.lock, flags);
+
+	for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
+		char *fbuf;
+		int fsize;
+		struct usb_iso_packet_descriptor *fin = &urb->iso_frame_desc[i];
+
+		if (fin->status == -EXDEV) {
+			shutdown = 1;
+			break;
+		}
+
+		fbuf = urb->transfer_buffer + fin->offset;
+		fsize = fin->actual_length;
+
+		if (fsize > line6pcm->max_packet_size_in) {
+			dev_err(line6pcm->line6->ifcdev,
+				"driver and/or device bug: packet too large (%d > %d)\n",
+				fsize, line6pcm->max_packet_size_in);
+		}
+
+		length += fsize;
+
+		BUILD_BUG_ON_MSG(LINE6_ISO_PACKETS != 1,
+			"The following code assumes LINE6_ISO_PACKETS == 1");
+		/* TODO:
+		 * Also, if iso_buffers != 2, the prev frame is almost random at
+		 * playback side.
+		 * This needs to be redesigned. It should be "stable", but we may
+		 * experience sync problems on such high-speed configs.
+		 */
+
+		line6pcm->prev_fbuf = fbuf;
+		line6pcm->prev_fsize = fsize /
+			(line6pcm->properties->bytes_per_channel *
+			line6pcm->properties->capture_hw.channels_max);
+
+		if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
+		    test_bit(LINE6_STREAM_PCM, &line6pcm->in.running) &&
+		    fsize > 0)
+			line6_capture_copy(line6pcm, fbuf, fsize);
+	}
+
+	clear_bit(index, &line6pcm->in.active_urbs);
+
+	if (test_and_clear_bit(index, &line6pcm->in.unlink_urbs))
+		shutdown = 1;
+
+	if (!shutdown) {
+		submit_audio_in_urb(line6pcm);
+
+		if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
+		    test_bit(LINE6_STREAM_PCM, &line6pcm->in.running))
+			line6_capture_check_period(line6pcm, length);
+	}
+
+	spin_unlock_irqrestore(&line6pcm->in.lock, flags);
+}
+
+/* open capture callback */
+static int snd_line6_capture_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->rates);
+	if (err < 0)
+		return err;
+
+	line6_pcm_acquire(line6pcm, LINE6_STREAM_CAPTURE_HELPER, false);
+
+	runtime->hw = line6pcm->properties->capture_hw;
+	return 0;
+}
+
+/* close capture callback */
+static int snd_line6_capture_close(struct snd_pcm_substream *substream)
+{
+	struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
+
+	line6_pcm_release(line6pcm, LINE6_STREAM_CAPTURE_HELPER);
+	return 0;
+}
+
+/* capture operators */
+const struct snd_pcm_ops snd_line6_capture_ops = {
+	.open = snd_line6_capture_open,
+	.close = snd_line6_capture_close,
+	.ioctl = snd_pcm_lib_ioctl,
+	.hw_params = snd_line6_hw_params,
+	.hw_free = snd_line6_hw_free,
+	.prepare = snd_line6_prepare,
+	.trigger = snd_line6_trigger,
+	.pointer = snd_line6_pointer,
+};
+
+int line6_create_audio_in_urbs(struct snd_line6_pcm *line6pcm)
+{
+	struct usb_line6 *line6 = line6pcm->line6;
+	int i;
+
+	line6pcm->in.urbs = kcalloc(line6->iso_buffers, sizeof(struct urb *),
+				    GFP_KERNEL);
+	if (line6pcm->in.urbs == NULL)
+		return -ENOMEM;
+
+	/* create audio URBs and fill in constant values: */
+	for (i = 0; i < line6->iso_buffers; ++i) {
+		struct urb *urb;
+
+		/* URB for audio in: */
+		urb = line6pcm->in.urbs[i] =
+		    usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
+
+		if (urb == NULL)
+			return -ENOMEM;
+
+		urb->dev = line6->usbdev;
+		urb->pipe =
+		    usb_rcvisocpipe(line6->usbdev,
+				    line6->properties->ep_audio_r &
+				    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_in_callback;
+		if (usb_urb_ep_type_check(urb))
+			return -EINVAL;
+	}
+
+	return 0;
+}