1 files changed, 429 insertions, 0 deletions

diff --git a/sound/usb/line6/playback.c b/sound/usb/line6/playback.c
new file mode 100644
index 000000000000..05dee690f487
--- /dev/null
+++ b/sound/usb/line6/playback.c
@@ -0,0 +1,429 @@
+/*
+ * 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"
+#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) {
+                __le16 *p, *buf_end;
+
+                p = (__le16 *)urb_out->transfer_buffer;
+                buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
+
+                for (; p < buf_end; ++p) {
+                        short pv = le16_to_cpu(*p);
+                        int val = (pv * volume[chn & 1]) >> 8;
+                        pv = clamp(val, 0x7fff, -0x8000);
+                        *p = cpu_to_le16(pv);
+                        ++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;
+                        val = clamp(val, 0x7fffff, -0x800000);
+                        p[0] = val;
+                        p[1] = val >> 8;
+                        p[2] = val >> 16;
+                        ++chn;
+                }
+        }
+}
+
+/*
+        Create signal for impulse response test.
+*/
+static void create_impulse_test_signal(struct snd_line6_pcm *line6pcm,
+                                       struct urb *urb_out, int bytes_per_frame)
+{
+        int frames = urb_out->transfer_buffer_length / bytes_per_frame;
+
+        if (bytes_per_frame == 4) {
+                int i;
+                short *pi = (short *)line6pcm->prev_fbuf;
+                short *po = (short *)urb_out->transfer_buffer;
+
+                for (i = 0; i < frames; ++i) {
+                        po[0] = pi[0];
+                        po[1] = 0;
+                        pi += 2;
+                        po += 2;
+                }
+        } else if (bytes_per_frame == 6) {
+                int i, j;
+                unsigned char *pi = line6pcm->prev_fbuf;
+                unsigned char *po = urb_out->transfer_buffer;
+
+                for (i = 0; i < frames; ++i) {
+                        for (j = 0; j < bytes_per_frame / 2; ++j)
+                                po[j] = pi[j];
+
+                        for (; j < bytes_per_frame; ++j)
+                                po[j] = 0;
+
+                        pi += bytes_per_frame;
+                        po += bytes_per_frame;
+                }
+        }
+        if (--line6pcm->impulse_count <= 0) {
+                ((unsigned char *)(urb_out->transfer_buffer))[bytes_per_frame -
+                                                              1] =
+                    line6pcm->impulse_volume;
+                line6pcm->impulse_count = line6pcm->impulse_period;
+        }
+}
+
+/*
+        Add signal to buffer for software monitoring.
+*/
+static void add_monitor_signal(struct urb *urb_out, unsigned char *signal,
+                               int volume, int bytes_per_frame)
+{
+        if (volume == 0)
+                return;         /* zero volume - no change */
+
+        if (bytes_per_frame == 4) {
+                __le16 *pi, *po, *buf_end;
+
+                pi = (__le16 *)signal;
+                po = (__le16 *)urb_out->transfer_buffer;
+                buf_end = po + urb_out->transfer_buffer_length / sizeof(*po);
+
+                for (; po < buf_end; ++pi, ++po) {
+                        short pov = le16_to_cpu(*po);
+                        short piv = le16_to_cpu(*pi);
+                        int val = pov + ((piv * volume) >> 8);
+                        pov = clamp(val, 0x7fff, -0x8000);
+                        *po = cpu_to_le16(pov);
+                }
+        }
+
+        /*
+           We don't need to handle devices with 6 bytes per frame here
+           since they all support hardware monitoring.
+         */
+}
+
+/*
+        Find a free URB, prepare audio data, and submit URB.
+        must be called in line6pcm->out.lock context
+*/
+static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm)
+{
+        int index;
+        int i, urb_size, urb_frames;
+        int ret;
+        const int bytes_per_frame = line6pcm->properties->bytes_per_frame;
+        const int frame_increment =
+                line6pcm->properties->rates.rats[0].num_min;
+        const int frame_factor =
+                line6pcm->properties->rates.rats[0].den *
+                (USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL);
+        struct urb *urb_out;
+
+        index =
+            find_first_zero_bit(&line6pcm->out.active_urbs, LINE6_ISO_BUFFERS);
+
+        if (index < 0 || index >= LINE6_ISO_BUFFERS) {
+                dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
+                return -EINVAL;
+        }
+
+        urb_out = line6pcm->out.urbs[index];
+        urb_size = 0;
+
+        for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
+                /* compute frame size for given sampling rate */
+                int fsize = 0;
+                struct usb_iso_packet_descriptor *fout =
+                    &urb_out->iso_frame_desc[i];
+
+                fsize = line6pcm->prev_fsize;
+                if (fsize == 0) {
+                        int n;
+
+                        line6pcm->out.count += frame_increment;
+                        n = line6pcm->out.count / frame_factor;
+                        line6pcm->out.count -= n * frame_factor;
+                        fsize = n * bytes_per_frame;
+                }
+
+                fout->offset = urb_size;
+                fout->length = fsize;
+                urb_size += fsize;
+        }
+
+        if (urb_size == 0) {
+                /* can't determine URB size */
+                dev_err(line6pcm->line6->ifcdev, "driver bug: urb_size = 0\n");
+                return -EINVAL;
+        }
+
+        urb_frames = urb_size / bytes_per_frame;
+        urb_out->transfer_buffer =
+            line6pcm->out.buffer +
+            index * LINE6_ISO_PACKETS * line6pcm->max_packet_size;
+        urb_out->transfer_buffer_length = urb_size;
+        urb_out->context = line6pcm;
+
+        if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running) &&
+            !test_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags)) {
+                struct snd_pcm_runtime *runtime =
+                    get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK)->runtime;
+
+                if (line6pcm->out.pos + 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->out.pos;
+
+                        if (len > 0) {
+                                memcpy(urb_out->transfer_buffer,
+                                       runtime->dma_area +
+                                       line6pcm->out.pos * bytes_per_frame,
+                                       len * bytes_per_frame);
+                                memcpy(urb_out->transfer_buffer +
+                                       len * bytes_per_frame, runtime->dma_area,
+                                       (urb_frames - len) * bytes_per_frame);
+                        } else
+                                dev_err(line6pcm->line6->ifcdev, "driver bug: len = %d\n",
+                                        len);
+                } else {
+                        memcpy(urb_out->transfer_buffer,
+                               runtime->dma_area +
+                               line6pcm->out.pos * bytes_per_frame,
+                               urb_out->transfer_buffer_length);
+                }
+
+                line6pcm->out.pos += urb_frames;
+                if (line6pcm->out.pos >= runtime->buffer_size)
+                        line6pcm->out.pos -= runtime->buffer_size;
+
+                change_volume(urb_out, line6pcm->volume_playback,
+                              bytes_per_frame);
+        } else {
+                memset(urb_out->transfer_buffer, 0,
+                       urb_out->transfer_buffer_length);
+        }
+
+        spin_lock_nested(&line6pcm->in.lock, SINGLE_DEPTH_NESTING);
+        if (line6pcm->prev_fbuf) {
+                if (test_bit(LINE6_STREAM_IMPULSE, &line6pcm->out.running)) {
+                        create_impulse_test_signal(line6pcm, urb_out,
+                                                   bytes_per_frame);
+                        if (test_bit(LINE6_STREAM_PCM, &line6pcm->in.running)) {
+                                line6_capture_copy(line6pcm,
+                                                   urb_out->transfer_buffer,
+                                                   urb_out->
+                                                   transfer_buffer_length);
+                                line6_capture_check_period(line6pcm,
+                                        urb_out->transfer_buffer_length);
+                        }
+                } else {
+                        if (!(line6pcm->line6->properties->capabilities & LINE6_CAP_HWMON)
+                            && line6pcm->out.running && line6pcm->in.running)
+                                add_monitor_signal(urb_out, line6pcm->prev_fbuf,
+                                                   line6pcm->volume_monitor,
+                                                   bytes_per_frame);
+                }
+                line6pcm->prev_fbuf = NULL;
+                line6pcm->prev_fsize = 0;
+        }
+        spin_unlock(&line6pcm->in.lock);
+
+        ret = usb_submit_urb(urb_out, GFP_ATOMIC);
+
+        if (ret == 0)
+                set_bit(index, &line6pcm->out.active_urbs);
+        else
+                dev_err(line6pcm->line6->ifcdev,
+                        "URB out #%d submission failed (%d)\n", index, ret);
+
+        return 0;
+}
+
+/*
+        Submit all currently available playback URBs.
+        must be called in line6pcm->out.lock context
+ */
+int line6_submit_audio_out_all_urbs(struct snd_line6_pcm *line6pcm)
+{
+        int ret = 0, i;
+
+        for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
+                ret = submit_audio_out_urb(line6pcm);
+                if (ret < 0)
+                        break;
+        }
+
+        return ret;
+}
+
+/*
+        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_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context;
+        struct snd_pcm_substream *substream =
+            get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK);
+
+#if USE_CLEAR_BUFFER_WORKAROUND
+        memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
+#endif
+
+        line6pcm->out.last_frame = urb->start_frame;
+
+        /* find index of URB */
+        for (index = 0; index < LINE6_ISO_BUFFERS; index++)
+                if (urb == line6pcm->out.urbs[index])
+                        break;
+
+        if (index >= LINE6_ISO_BUFFERS)
+                return;         /* URB has been unlinked asynchronously */
+
+        for (i = 0; i < LINE6_ISO_PACKETS; i++)
+                length += urb->iso_frame_desc[i].length;
+
+        spin_lock_irqsave(&line6pcm->out.lock, flags);
+
+        if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) {
+                struct snd_pcm_runtime *runtime = substream->runtime;
+
+                line6pcm->out.pos_done +=
+                    length / line6pcm->properties->bytes_per_frame;
+
+                if (line6pcm->out.pos_done >= runtime->buffer_size)
+                        line6pcm->out.pos_done -= runtime->buffer_size;
+        }
+
+        clear_bit(index, &line6pcm->out.active_urbs);
+
+        for (i = 0; i < LINE6_ISO_PACKETS; i++)
+                if (urb->iso_frame_desc[i].status == -EXDEV) {
+                        shutdown = 1;
+                        break;
+                }
+
+        if (test_and_clear_bit(index, &line6pcm->out.unlink_urbs))
+                shutdown = 1;
+
+        if (!shutdown) {
+                submit_audio_out_urb(line6pcm);
+
+                if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) {
+                        line6pcm->out.bytes += length;
+                        if (line6pcm->out.bytes >= line6pcm->out.period) {
+                                line6pcm->out.bytes %= line6pcm->out.period;
+                                spin_unlock(&line6pcm->out.lock);
+                                snd_pcm_period_elapsed(substream);
+                                spin_lock(&line6pcm->out.lock);
+                        }
+                }
+        }
+        spin_unlock_irqrestore(&line6pcm->out.lock, flags);
+}
+
+/* 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->rates);
+        if (err < 0)
+                return err;
+
+        runtime->hw = line6pcm->properties->playback_hw;
+        return 0;
+}
+
+/* close playback callback */
+static int snd_line6_playback_close(struct snd_pcm_substream *substream)
+{
+        return 0;
+}
+
+/* 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_hw_params,
+        .hw_free = snd_line6_hw_free,
+        .prepare = snd_line6_prepare,
+        .trigger = snd_line6_trigger,
+        .pointer = snd_line6_pointer,
+};
+
+int line6_create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
+{
+        struct usb_line6 *line6 = line6pcm->line6;
+        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->out.urbs[i] =
+                    usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
+
+                if (urb == NULL)
+                        return -ENOMEM;
+
+                urb->dev = line6->usbdev;
+                urb->pipe =
+                    usb_sndisocpipe(line6->usbdev,
+                                    line6->properties->ep_audio_w &
+                                    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;
+}