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607 lines
16 KiB
607 lines
16 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* Line 6 Linux USB driver |
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* |
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* Copyright (C) 2004-2010 Markus Grabner ([email protected]) |
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*/ |
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|
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#include <linux/slab.h> |
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#include <linux/export.h> |
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#include <sound/core.h> |
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#include <sound/control.h> |
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#include <sound/pcm.h> |
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#include <sound/pcm_params.h> |
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#include "capture.h" |
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#include "driver.h" |
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#include "playback.h" |
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/* impulse response volume controls */ |
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static int snd_line6_impulse_volume_info(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_info *uinfo) |
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{ |
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uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; |
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uinfo->count = 1; |
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uinfo->value.integer.min = 0; |
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uinfo->value.integer.max = 255; |
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return 0; |
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} |
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static int snd_line6_impulse_volume_get(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_value *ucontrol) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol); |
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ucontrol->value.integer.value[0] = line6pcm->impulse_volume; |
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return 0; |
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} |
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static int snd_line6_impulse_volume_put(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_value *ucontrol) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol); |
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int value = ucontrol->value.integer.value[0]; |
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int err; |
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if (line6pcm->impulse_volume == value) |
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return 0; |
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line6pcm->impulse_volume = value; |
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if (value > 0) { |
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err = line6_pcm_acquire(line6pcm, LINE6_STREAM_IMPULSE, true); |
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if (err < 0) { |
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line6pcm->impulse_volume = 0; |
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return err; |
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} |
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} else { |
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line6_pcm_release(line6pcm, LINE6_STREAM_IMPULSE); |
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} |
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return 1; |
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} |
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/* impulse response period controls */ |
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static int snd_line6_impulse_period_info(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_info *uinfo) |
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{ |
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uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; |
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uinfo->count = 1; |
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uinfo->value.integer.min = 0; |
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uinfo->value.integer.max = 2000; |
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return 0; |
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} |
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static int snd_line6_impulse_period_get(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_value *ucontrol) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol); |
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ucontrol->value.integer.value[0] = line6pcm->impulse_period; |
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return 0; |
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} |
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static int snd_line6_impulse_period_put(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_value *ucontrol) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol); |
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int value = ucontrol->value.integer.value[0]; |
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if (line6pcm->impulse_period == value) |
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return 0; |
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line6pcm->impulse_period = value; |
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return 1; |
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} |
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/* |
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Unlink all currently active URBs. |
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*/ |
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static void line6_unlink_audio_urbs(struct snd_line6_pcm *line6pcm, |
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struct line6_pcm_stream *pcms) |
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{ |
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int i; |
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for (i = 0; i < line6pcm->line6->iso_buffers; i++) { |
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if (test_bit(i, &pcms->active_urbs)) { |
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if (!test_and_set_bit(i, &pcms->unlink_urbs)) |
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usb_unlink_urb(pcms->urbs[i]); |
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} |
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} |
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} |
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/* |
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Wait until unlinking of all currently active URBs has been finished. |
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*/ |
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static void line6_wait_clear_audio_urbs(struct snd_line6_pcm *line6pcm, |
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struct line6_pcm_stream *pcms) |
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{ |
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int timeout = HZ; |
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int i; |
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int alive; |
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do { |
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alive = 0; |
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for (i = 0; i < line6pcm->line6->iso_buffers; i++) { |
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if (test_bit(i, &pcms->active_urbs)) |
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alive++; |
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} |
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if (!alive) |
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break; |
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set_current_state(TASK_UNINTERRUPTIBLE); |
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schedule_timeout(1); |
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} while (--timeout > 0); |
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if (alive) |
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dev_err(line6pcm->line6->ifcdev, |
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"timeout: still %d active urbs..\n", alive); |
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} |
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static inline struct line6_pcm_stream * |
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get_stream(struct snd_line6_pcm *line6pcm, int direction) |
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{ |
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return (direction == SNDRV_PCM_STREAM_PLAYBACK) ? |
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&line6pcm->out : &line6pcm->in; |
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} |
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/* allocate a buffer if not opened yet; |
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* call this in line6pcm.state_mutex |
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*/ |
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static int line6_buffer_acquire(struct snd_line6_pcm *line6pcm, |
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struct line6_pcm_stream *pstr, int direction, int type) |
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{ |
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const int pkt_size = |
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(direction == SNDRV_PCM_STREAM_PLAYBACK) ? |
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line6pcm->max_packet_size_out : |
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line6pcm->max_packet_size_in; |
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/* Invoked multiple times in a row so allocate once only */ |
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if (!test_and_set_bit(type, &pstr->opened) && !pstr->buffer) { |
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pstr->buffer = |
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kmalloc(array3_size(line6pcm->line6->iso_buffers, |
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LINE6_ISO_PACKETS, pkt_size), |
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GFP_KERNEL); |
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if (!pstr->buffer) |
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return -ENOMEM; |
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} |
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return 0; |
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} |
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/* free a buffer if all streams are closed; |
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* call this in line6pcm.state_mutex |
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*/ |
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static void line6_buffer_release(struct snd_line6_pcm *line6pcm, |
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struct line6_pcm_stream *pstr, int type) |
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{ |
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clear_bit(type, &pstr->opened); |
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if (!pstr->opened) { |
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line6_wait_clear_audio_urbs(line6pcm, pstr); |
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kfree(pstr->buffer); |
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pstr->buffer = NULL; |
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} |
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} |
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/* start a PCM stream */ |
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static int line6_stream_start(struct snd_line6_pcm *line6pcm, int direction, |
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int type) |
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{ |
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unsigned long flags; |
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struct line6_pcm_stream *pstr = get_stream(line6pcm, direction); |
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int ret = 0; |
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spin_lock_irqsave(&pstr->lock, flags); |
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if (!test_and_set_bit(type, &pstr->running) && |
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!(pstr->active_urbs || pstr->unlink_urbs)) { |
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pstr->count = 0; |
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/* Submit all currently available URBs */ |
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if (direction == SNDRV_PCM_STREAM_PLAYBACK) |
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ret = line6_submit_audio_out_all_urbs(line6pcm); |
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else |
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ret = line6_submit_audio_in_all_urbs(line6pcm); |
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} |
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if (ret < 0) |
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clear_bit(type, &pstr->running); |
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spin_unlock_irqrestore(&pstr->lock, flags); |
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return ret; |
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} |
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/* stop a PCM stream; this doesn't sync with the unlinked URBs */ |
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static void line6_stream_stop(struct snd_line6_pcm *line6pcm, int direction, |
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int type) |
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{ |
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unsigned long flags; |
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struct line6_pcm_stream *pstr = get_stream(line6pcm, direction); |
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spin_lock_irqsave(&pstr->lock, flags); |
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clear_bit(type, &pstr->running); |
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if (!pstr->running) { |
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spin_unlock_irqrestore(&pstr->lock, flags); |
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line6_unlink_audio_urbs(line6pcm, pstr); |
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spin_lock_irqsave(&pstr->lock, flags); |
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if (direction == SNDRV_PCM_STREAM_CAPTURE) { |
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line6pcm->prev_fbuf = NULL; |
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line6pcm->prev_fsize = 0; |
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} |
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} |
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spin_unlock_irqrestore(&pstr->lock, flags); |
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} |
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/* common PCM trigger callback */ |
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int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream); |
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struct snd_pcm_substream *s; |
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int err; |
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clear_bit(LINE6_FLAG_PREPARED, &line6pcm->flags); |
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snd_pcm_group_for_each_entry(s, substream) { |
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if (s->pcm->card != substream->pcm->card) |
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continue; |
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switch (cmd) { |
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case SNDRV_PCM_TRIGGER_START: |
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case SNDRV_PCM_TRIGGER_RESUME: |
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if (s->stream == SNDRV_PCM_STREAM_CAPTURE && |
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(line6pcm->line6->properties->capabilities & |
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LINE6_CAP_IN_NEEDS_OUT)) { |
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err = line6_stream_start(line6pcm, SNDRV_PCM_STREAM_PLAYBACK, |
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LINE6_STREAM_CAPTURE_HELPER); |
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if (err < 0) |
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return err; |
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} |
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err = line6_stream_start(line6pcm, s->stream, |
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LINE6_STREAM_PCM); |
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if (err < 0) |
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return err; |
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break; |
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case SNDRV_PCM_TRIGGER_STOP: |
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case SNDRV_PCM_TRIGGER_SUSPEND: |
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if (s->stream == SNDRV_PCM_STREAM_CAPTURE && |
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(line6pcm->line6->properties->capabilities & |
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LINE6_CAP_IN_NEEDS_OUT)) { |
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line6_stream_stop(line6pcm, SNDRV_PCM_STREAM_PLAYBACK, |
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LINE6_STREAM_CAPTURE_HELPER); |
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} |
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line6_stream_stop(line6pcm, s->stream, |
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LINE6_STREAM_PCM); |
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break; |
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case SNDRV_PCM_TRIGGER_PAUSE_PUSH: |
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if (s->stream != SNDRV_PCM_STREAM_PLAYBACK) |
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return -EINVAL; |
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set_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags); |
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break; |
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case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: |
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if (s->stream != SNDRV_PCM_STREAM_PLAYBACK) |
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return -EINVAL; |
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clear_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags); |
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break; |
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default: |
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return -EINVAL; |
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} |
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} |
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return 0; |
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} |
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/* common PCM pointer callback */ |
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snd_pcm_uframes_t snd_line6_pointer(struct snd_pcm_substream *substream) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream); |
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struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream); |
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return pstr->pos_done; |
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} |
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/* Acquire and optionally start duplex streams: |
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* type is either LINE6_STREAM_IMPULSE or LINE6_STREAM_MONITOR |
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*/ |
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int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int type, bool start) |
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{ |
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struct line6_pcm_stream *pstr; |
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int ret = 0, dir; |
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/* TODO: We should assert SNDRV_PCM_STREAM_PLAYBACK/CAPTURE == 0/1 */ |
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mutex_lock(&line6pcm->state_mutex); |
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for (dir = 0; dir < 2; dir++) { |
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pstr = get_stream(line6pcm, dir); |
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ret = line6_buffer_acquire(line6pcm, pstr, dir, type); |
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if (ret < 0) |
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goto error; |
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if (!pstr->running) |
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line6_wait_clear_audio_urbs(line6pcm, pstr); |
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} |
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if (start) { |
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for (dir = 0; dir < 2; dir++) { |
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ret = line6_stream_start(line6pcm, dir, type); |
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if (ret < 0) |
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goto error; |
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} |
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} |
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error: |
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mutex_unlock(&line6pcm->state_mutex); |
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if (ret < 0) |
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line6_pcm_release(line6pcm, type); |
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return ret; |
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} |
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EXPORT_SYMBOL_GPL(line6_pcm_acquire); |
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/* Stop and release duplex streams */ |
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void line6_pcm_release(struct snd_line6_pcm *line6pcm, int type) |
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{ |
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struct line6_pcm_stream *pstr; |
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int dir; |
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mutex_lock(&line6pcm->state_mutex); |
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for (dir = 0; dir < 2; dir++) |
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line6_stream_stop(line6pcm, dir, type); |
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for (dir = 0; dir < 2; dir++) { |
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pstr = get_stream(line6pcm, dir); |
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line6_buffer_release(line6pcm, pstr, type); |
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} |
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mutex_unlock(&line6pcm->state_mutex); |
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} |
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EXPORT_SYMBOL_GPL(line6_pcm_release); |
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/* common PCM hw_params callback */ |
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int snd_line6_hw_params(struct snd_pcm_substream *substream, |
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struct snd_pcm_hw_params *hw_params) |
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{ |
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int ret; |
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struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream); |
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struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream); |
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mutex_lock(&line6pcm->state_mutex); |
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ret = line6_buffer_acquire(line6pcm, pstr, substream->stream, |
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LINE6_STREAM_PCM); |
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if (ret < 0) |
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goto error; |
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pstr->period = params_period_bytes(hw_params); |
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error: |
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mutex_unlock(&line6pcm->state_mutex); |
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return ret; |
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} |
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/* common PCM hw_free callback */ |
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int snd_line6_hw_free(struct snd_pcm_substream *substream) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream); |
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struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream); |
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mutex_lock(&line6pcm->state_mutex); |
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line6_buffer_release(line6pcm, pstr, LINE6_STREAM_PCM); |
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mutex_unlock(&line6pcm->state_mutex); |
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return 0; |
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} |
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/* control info callback */ |
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static int snd_line6_control_playback_info(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_info *uinfo) |
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{ |
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uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; |
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uinfo->count = 2; |
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uinfo->value.integer.min = 0; |
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uinfo->value.integer.max = 256; |
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return 0; |
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} |
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/* control get callback */ |
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static int snd_line6_control_playback_get(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_value *ucontrol) |
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{ |
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int i; |
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struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol); |
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for (i = 0; i < 2; i++) |
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ucontrol->value.integer.value[i] = line6pcm->volume_playback[i]; |
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return 0; |
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} |
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/* control put callback */ |
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static int snd_line6_control_playback_put(struct snd_kcontrol *kcontrol, |
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struct snd_ctl_elem_value *ucontrol) |
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{ |
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int i, changed = 0; |
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struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol); |
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for (i = 0; i < 2; i++) |
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if (line6pcm->volume_playback[i] != |
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ucontrol->value.integer.value[i]) { |
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line6pcm->volume_playback[i] = |
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ucontrol->value.integer.value[i]; |
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changed = 1; |
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} |
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return changed; |
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} |
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/* control definition */ |
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static const struct snd_kcontrol_new line6_controls[] = { |
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{ |
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.iface = SNDRV_CTL_ELEM_IFACE_MIXER, |
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.name = "PCM Playback Volume", |
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.info = snd_line6_control_playback_info, |
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.get = snd_line6_control_playback_get, |
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.put = snd_line6_control_playback_put |
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}, |
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{ |
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.iface = SNDRV_CTL_ELEM_IFACE_MIXER, |
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.name = "Impulse Response Volume", |
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.info = snd_line6_impulse_volume_info, |
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.get = snd_line6_impulse_volume_get, |
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.put = snd_line6_impulse_volume_put |
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}, |
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{ |
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.iface = SNDRV_CTL_ELEM_IFACE_MIXER, |
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.name = "Impulse Response Period", |
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.info = snd_line6_impulse_period_info, |
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.get = snd_line6_impulse_period_get, |
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.put = snd_line6_impulse_period_put |
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}, |
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}; |
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/* |
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Cleanup the PCM device. |
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*/ |
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static void cleanup_urbs(struct line6_pcm_stream *pcms, int iso_buffers) |
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{ |
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int i; |
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|
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/* Most likely impossible in current code... */ |
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if (pcms->urbs == NULL) |
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return; |
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for (i = 0; i < iso_buffers; i++) { |
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if (pcms->urbs[i]) { |
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usb_kill_urb(pcms->urbs[i]); |
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usb_free_urb(pcms->urbs[i]); |
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} |
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} |
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kfree(pcms->urbs); |
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pcms->urbs = NULL; |
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} |
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static void line6_cleanup_pcm(struct snd_pcm *pcm) |
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{ |
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struct snd_line6_pcm *line6pcm = snd_pcm_chip(pcm); |
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cleanup_urbs(&line6pcm->out, line6pcm->line6->iso_buffers); |
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cleanup_urbs(&line6pcm->in, line6pcm->line6->iso_buffers); |
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kfree(line6pcm); |
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} |
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/* create a PCM device */ |
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static int snd_line6_new_pcm(struct usb_line6 *line6, struct snd_pcm **pcm_ret) |
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{ |
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struct snd_pcm *pcm; |
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int err; |
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err = snd_pcm_new(line6->card, (char *)line6->properties->name, |
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0, 1, 1, pcm_ret); |
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if (err < 0) |
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return err; |
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pcm = *pcm_ret; |
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strcpy(pcm->name, line6->properties->name); |
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|
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/* set operators */ |
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snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, |
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&snd_line6_playback_ops); |
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snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_line6_capture_ops); |
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|
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/* pre-allocation of buffers */ |
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snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, |
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NULL, 64 * 1024, 128 * 1024); |
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return 0; |
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} |
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|
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/* |
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Sync with PCM stream stops. |
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*/ |
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void line6_pcm_disconnect(struct snd_line6_pcm *line6pcm) |
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{ |
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line6_unlink_audio_urbs(line6pcm, &line6pcm->out); |
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line6_unlink_audio_urbs(line6pcm, &line6pcm->in); |
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line6_wait_clear_audio_urbs(line6pcm, &line6pcm->out); |
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line6_wait_clear_audio_urbs(line6pcm, &line6pcm->in); |
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} |
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/* |
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Create and register the PCM device and mixer entries. |
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Create URBs for playback and capture. |
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*/ |
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int line6_init_pcm(struct usb_line6 *line6, |
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struct line6_pcm_properties *properties) |
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{ |
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int i, err; |
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unsigned ep_read = line6->properties->ep_audio_r; |
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unsigned ep_write = line6->properties->ep_audio_w; |
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struct snd_pcm *pcm; |
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struct snd_line6_pcm *line6pcm; |
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|
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if (!(line6->properties->capabilities & LINE6_CAP_PCM)) |
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return 0; /* skip PCM initialization and report success */ |
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err = snd_line6_new_pcm(line6, &pcm); |
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if (err < 0) |
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return err; |
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line6pcm = kzalloc(sizeof(*line6pcm), GFP_KERNEL); |
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if (!line6pcm) |
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return -ENOMEM; |
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mutex_init(&line6pcm->state_mutex); |
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line6pcm->pcm = pcm; |
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line6pcm->properties = properties; |
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line6pcm->volume_playback[0] = line6pcm->volume_playback[1] = 255; |
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line6pcm->volume_monitor = 255; |
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line6pcm->line6 = line6; |
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|
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spin_lock_init(&line6pcm->out.lock); |
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spin_lock_init(&line6pcm->in.lock); |
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line6pcm->impulse_period = LINE6_IMPULSE_DEFAULT_PERIOD; |
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|
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line6->line6pcm = line6pcm; |
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|
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pcm->private_data = line6pcm; |
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pcm->private_free = line6_cleanup_pcm; |
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|
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line6pcm->max_packet_size_in = |
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usb_maxpacket(line6->usbdev, |
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usb_rcvisocpipe(line6->usbdev, ep_read), 0); |
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line6pcm->max_packet_size_out = |
|
usb_maxpacket(line6->usbdev, |
|
usb_sndisocpipe(line6->usbdev, ep_write), 1); |
|
if (!line6pcm->max_packet_size_in || !line6pcm->max_packet_size_out) { |
|
dev_err(line6pcm->line6->ifcdev, |
|
"cannot get proper max packet size\n"); |
|
return -EINVAL; |
|
} |
|
|
|
err = line6_create_audio_out_urbs(line6pcm); |
|
if (err < 0) |
|
return err; |
|
|
|
err = line6_create_audio_in_urbs(line6pcm); |
|
if (err < 0) |
|
return err; |
|
|
|
/* mixer: */ |
|
for (i = 0; i < ARRAY_SIZE(line6_controls); i++) { |
|
err = snd_ctl_add(line6->card, |
|
snd_ctl_new1(&line6_controls[i], line6pcm)); |
|
if (err < 0) |
|
return err; |
|
} |
|
|
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(line6_init_pcm); |
|
|
|
/* prepare pcm callback */ |
|
int snd_line6_prepare(struct snd_pcm_substream *substream) |
|
{ |
|
struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream); |
|
struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream); |
|
|
|
mutex_lock(&line6pcm->state_mutex); |
|
if (!pstr->running) |
|
line6_wait_clear_audio_urbs(line6pcm, pstr); |
|
|
|
if (!test_and_set_bit(LINE6_FLAG_PREPARED, &line6pcm->flags)) { |
|
line6pcm->out.count = 0; |
|
line6pcm->out.pos = 0; |
|
line6pcm->out.pos_done = 0; |
|
line6pcm->out.bytes = 0; |
|
line6pcm->in.count = 0; |
|
line6pcm->in.pos_done = 0; |
|
line6pcm->in.bytes = 0; |
|
} |
|
|
|
mutex_unlock(&line6pcm->state_mutex); |
|
return 0; |
|
}
|
|
|