Adding upstream version 14.2.upstream/14.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2473 insertions, 0 deletions

diff --git a/src/modules/alsa/alsa-source.c b/src/modules/alsa/alsa-source.c
new file mode 100644
index 0000000..76370f8
--- /dev/null
+++ b/src/modules/alsa/alsa-source.c
@@ -0,0 +1,2473 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2004-2008 Lennart Poettering
+  Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as published
+  by the Free Software Foundation; either version 2.1 of the License,
+  or (at your option) any later version.
+
+  PulseAudio 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 Lesser General Public License
+  along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <signal.h>
+#include <stdio.h>
+
+#include <alsa/asoundlib.h>
+
+#include <pulse/rtclock.h>
+#include <pulse/timeval.h>
+#include <pulse/util.h>
+#include <pulse/volume.h>
+#include <pulse/xmalloc.h>
+
+#include <pulsecore/core.h>
+#include <pulsecore/i18n.h>
+#include <pulsecore/module.h>
+#include <pulsecore/memchunk.h>
+#include <pulsecore/sink.h>
+#include <pulsecore/modargs.h>
+#include <pulsecore/core-rtclock.h>
+#include <pulsecore/core-util.h>
+#include <pulsecore/sample-util.h>
+#include <pulsecore/log.h>
+#include <pulsecore/macro.h>
+#include <pulsecore/thread.h>
+#include <pulsecore/thread-mq.h>
+#include <pulsecore/rtpoll.h>
+#include <pulsecore/time-smoother.h>
+
+#include <modules/reserve-wrap.h>
+
+#include "alsa-util.h"
+#include "alsa-source.h"
+
+/* #define DEBUG_TIMING */
+
+#define DEFAULT_DEVICE "default"
+
+#define DEFAULT_TSCHED_BUFFER_USEC (2*PA_USEC_PER_SEC)             /* 2s */
+#define DEFAULT_TSCHED_WATERMARK_USEC (20*PA_USEC_PER_MSEC)        /* 20ms */
+
+#define TSCHED_WATERMARK_INC_STEP_USEC (10*PA_USEC_PER_MSEC)       /* 10ms  */
+#define TSCHED_WATERMARK_DEC_STEP_USEC (5*PA_USEC_PER_MSEC)        /* 5ms */
+#define TSCHED_WATERMARK_VERIFY_AFTER_USEC (20*PA_USEC_PER_SEC)    /* 20s */
+#define TSCHED_WATERMARK_INC_THRESHOLD_USEC (0*PA_USEC_PER_MSEC)   /* 0ms */
+#define TSCHED_WATERMARK_DEC_THRESHOLD_USEC (100*PA_USEC_PER_MSEC) /* 100ms */
+#define TSCHED_WATERMARK_STEP_USEC (10*PA_USEC_PER_MSEC)           /* 10ms */
+
+#define TSCHED_MIN_SLEEP_USEC (10*PA_USEC_PER_MSEC)                /* 10ms */
+#define TSCHED_MIN_WAKEUP_USEC (4*PA_USEC_PER_MSEC)                /* 4ms */
+
+#define SMOOTHER_WINDOW_USEC  (10*PA_USEC_PER_SEC)                 /* 10s */
+#define SMOOTHER_ADJUST_USEC  (1*PA_USEC_PER_SEC)                  /* 1s */
+
+#define SMOOTHER_MIN_INTERVAL (2*PA_USEC_PER_MSEC)                 /* 2ms */
+#define SMOOTHER_MAX_INTERVAL (200*PA_USEC_PER_MSEC)               /* 200ms */
+
+#define VOLUME_ACCURACY (PA_VOLUME_NORM/100)
+
+struct userdata {
+    pa_core *core;
+    pa_module *module;
+    pa_source *source;
+
+    pa_thread *thread;
+    pa_thread_mq thread_mq;
+    pa_rtpoll *rtpoll;
+
+    snd_pcm_t *pcm_handle;
+
+    char *paths_dir;
+    pa_alsa_fdlist *mixer_fdl;
+    pa_alsa_mixer_pdata *mixer_pd;
+    pa_hashmap *mixers;
+    snd_mixer_t *mixer_handle;
+    pa_alsa_path_set *mixer_path_set;
+    pa_alsa_path *mixer_path;
+
+    pa_cvolume hardware_volume;
+
+    pa_sample_spec verified_sample_spec;
+    pa_sample_format_t *supported_formats;
+    unsigned int *supported_rates;
+    struct {
+        size_t fragment_size;
+        size_t nfrags;
+        size_t tsched_size;
+        size_t tsched_watermark;
+    } initial_info;
+
+    size_t
+        frame_size,
+        fragment_size,
+        hwbuf_size,
+        tsched_size,
+        tsched_watermark,
+        tsched_watermark_ref,
+        hwbuf_unused,
+        min_sleep,
+        min_wakeup,
+        watermark_inc_step,
+        watermark_dec_step,
+        watermark_inc_threshold,
+        watermark_dec_threshold;
+
+    snd_pcm_uframes_t frames_per_block;
+
+    pa_usec_t watermark_dec_not_before;
+    pa_usec_t min_latency_ref;
+    pa_usec_t tsched_watermark_usec;
+
+    char *device_name;  /* name of the PCM device */
+    char *control_device; /* name of the control device */
+
+    bool use_mmap:1, use_tsched:1, deferred_volume:1, fixed_latency_range:1;
+
+    bool first;
+
+    pa_rtpoll_item *alsa_rtpoll_item;
+
+    pa_smoother *smoother;
+    uint64_t read_count;
+    pa_usec_t smoother_interval;
+    pa_usec_t last_smoother_update;
+
+    pa_reserve_wrapper *reserve;
+    pa_hook_slot *reserve_slot;
+    pa_reserve_monitor_wrapper *monitor;
+    pa_hook_slot *monitor_slot;
+
+    /* ucm context */
+    pa_alsa_ucm_mapping_context *ucm_context;
+};
+
+enum {
+    SOURCE_MESSAGE_SYNC_MIXER = PA_SOURCE_MESSAGE_MAX
+};
+
+static void userdata_free(struct userdata *u);
+static int unsuspend(struct userdata *u, bool recovering);
+
+static pa_hook_result_t reserve_cb(pa_reserve_wrapper *r, void *forced, struct userdata *u) {
+    pa_assert(r);
+    pa_assert(u);
+
+    pa_log_debug("Suspending source %s, because another application requested us to release the device.", u->source->name);
+
+    if (pa_source_suspend(u->source, true, PA_SUSPEND_APPLICATION) < 0)
+        return PA_HOOK_CANCEL;
+
+    return PA_HOOK_OK;
+}
+
+static void reserve_done(struct userdata *u) {
+    pa_assert(u);
+
+    if (u->reserve_slot) {
+        pa_hook_slot_free(u->reserve_slot);
+        u->reserve_slot = NULL;
+    }
+
+    if (u->reserve) {
+        pa_reserve_wrapper_unref(u->reserve);
+        u->reserve = NULL;
+    }
+}
+
+static void reserve_update(struct userdata *u) {
+    const char *description;
+    pa_assert(u);
+
+    if (!u->source || !u->reserve)
+        return;
+
+    if ((description = pa_proplist_gets(u->source->proplist, PA_PROP_DEVICE_DESCRIPTION)))
+        pa_reserve_wrapper_set_application_device_name(u->reserve, description);
+}
+
+static int reserve_init(struct userdata *u, const char *dname) {
+    char *rname;
+
+    pa_assert(u);
+    pa_assert(dname);
+
+    if (u->reserve)
+        return 0;
+
+    if (pa_in_system_mode())
+        return 0;
+
+    if (!(rname = pa_alsa_get_reserve_name(dname)))
+        return 0;
+
+    /* We are resuming, try to lock the device */
+    u->reserve = pa_reserve_wrapper_get(u->core, rname);
+    pa_xfree(rname);
+
+    if (!(u->reserve))
+        return -1;
+
+    reserve_update(u);
+
+    pa_assert(!u->reserve_slot);
+    u->reserve_slot = pa_hook_connect(pa_reserve_wrapper_hook(u->reserve), PA_HOOK_NORMAL, (pa_hook_cb_t) reserve_cb, u);
+
+    return 0;
+}
+
+static pa_hook_result_t monitor_cb(pa_reserve_monitor_wrapper *w, void* busy, struct userdata *u) {
+    pa_assert(w);
+    pa_assert(u);
+
+    if (PA_PTR_TO_UINT(busy) && !u->reserve) {
+        pa_log_debug("Suspending source %s, because another application is blocking the access to the device.", u->source->name);
+        pa_source_suspend(u->source, true, PA_SUSPEND_APPLICATION);
+    } else {
+        pa_log_debug("Resuming source %s, because other applications aren't blocking access to the device any more.", u->source->name);
+        pa_source_suspend(u->source, false, PA_SUSPEND_APPLICATION);
+    }
+
+    return PA_HOOK_OK;
+}
+
+static void monitor_done(struct userdata *u) {
+    pa_assert(u);
+
+    if (u->monitor_slot) {
+        pa_hook_slot_free(u->monitor_slot);
+        u->monitor_slot = NULL;
+    }
+
+    if (u->monitor) {
+        pa_reserve_monitor_wrapper_unref(u->monitor);
+        u->monitor = NULL;
+    }
+}
+
+static int reserve_monitor_init(struct userdata *u, const char *dname) {
+    char *rname;
+
+    pa_assert(u);
+    pa_assert(dname);
+
+    if (pa_in_system_mode())
+        return 0;
+
+    if (!(rname = pa_alsa_get_reserve_name(dname)))
+        return 0;
+
+    /* We are resuming, try to lock the device */
+    u->monitor = pa_reserve_monitor_wrapper_get(u->core, rname);
+    pa_xfree(rname);
+
+    if (!(u->monitor))
+        return -1;
+
+    pa_assert(!u->monitor_slot);
+    u->monitor_slot = pa_hook_connect(pa_reserve_monitor_wrapper_hook(u->monitor), PA_HOOK_NORMAL, (pa_hook_cb_t) monitor_cb, u);
+
+    return 0;
+}
+
+static void fix_min_sleep_wakeup(struct userdata *u) {
+    size_t max_use, max_use_2;
+
+    pa_assert(u);
+    pa_assert(u->use_tsched);
+
+    max_use = u->hwbuf_size - u->hwbuf_unused;
+    max_use_2 = pa_frame_align(max_use/2, &u->source->sample_spec);
+
+    u->min_sleep = pa_usec_to_bytes(TSCHED_MIN_SLEEP_USEC, &u->source->sample_spec);
+    u->min_sleep = PA_CLAMP(u->min_sleep, u->frame_size, max_use_2);
+
+    u->min_wakeup = pa_usec_to_bytes(TSCHED_MIN_WAKEUP_USEC, &u->source->sample_spec);
+    u->min_wakeup = PA_CLAMP(u->min_wakeup, u->frame_size, max_use_2);
+}
+
+static void fix_tsched_watermark(struct userdata *u) {
+    size_t max_use;
+    pa_assert(u);
+    pa_assert(u->use_tsched);
+
+    max_use = u->hwbuf_size - u->hwbuf_unused;
+
+    if (u->tsched_watermark > max_use - u->min_sleep)
+        u->tsched_watermark = max_use - u->min_sleep;
+
+    if (u->tsched_watermark < u->min_wakeup)
+        u->tsched_watermark = u->min_wakeup;
+
+   u->tsched_watermark_usec = pa_bytes_to_usec(u->tsched_watermark, &u->source->sample_spec);
+}
+
+static void increase_watermark(struct userdata *u) {
+    size_t old_watermark;
+    pa_usec_t old_min_latency, new_min_latency;
+
+    pa_assert(u);
+    pa_assert(u->use_tsched);
+
+    /* First, just try to increase the watermark */
+    old_watermark = u->tsched_watermark;
+    u->tsched_watermark = PA_MIN(u->tsched_watermark * 2, u->tsched_watermark + u->watermark_inc_step);
+    fix_tsched_watermark(u);
+
+    if (old_watermark != u->tsched_watermark) {
+        pa_log_info("Increasing wakeup watermark to %0.2f ms",
+                    (double) u->tsched_watermark_usec / PA_USEC_PER_MSEC);
+        return;
+    }
+
+    /* Hmm, we cannot increase the watermark any further, hence let's
+     raise the latency unless doing so was disabled in
+     configuration */
+    if (u->fixed_latency_range)
+        return;
+
+    old_min_latency = u->source->thread_info.min_latency;
+    new_min_latency = PA_MIN(old_min_latency * 2, old_min_latency + TSCHED_WATERMARK_INC_STEP_USEC);
+    new_min_latency = PA_MIN(new_min_latency, u->source->thread_info.max_latency);
+
+    if (old_min_latency != new_min_latency) {
+        pa_log_info("Increasing minimal latency to %0.2f ms",
+                    (double) new_min_latency / PA_USEC_PER_MSEC);
+
+        pa_source_set_latency_range_within_thread(u->source, new_min_latency, u->source->thread_info.max_latency);
+    }
+
+    /* When we reach this we're officially fucked! */
+}
+
+static void decrease_watermark(struct userdata *u) {
+    size_t old_watermark;
+    pa_usec_t now;
+
+    pa_assert(u);
+    pa_assert(u->use_tsched);
+
+    now = pa_rtclock_now();
+
+    if (u->watermark_dec_not_before <= 0)
+        goto restart;
+
+    if (u->watermark_dec_not_before > now)
+        return;
+
+    old_watermark = u->tsched_watermark;
+
+    if (u->tsched_watermark < u->watermark_dec_step)
+        u->tsched_watermark = u->tsched_watermark / 2;
+    else
+        u->tsched_watermark = PA_MAX(u->tsched_watermark / 2, u->tsched_watermark - u->watermark_dec_step);
+
+    fix_tsched_watermark(u);
+
+    if (old_watermark != u->tsched_watermark)
+        pa_log_info("Decreasing wakeup watermark to %0.2f ms",
+                    (double) u->tsched_watermark_usec / PA_USEC_PER_MSEC);
+
+    /* We don't change the latency range*/
+
+restart:
+    u->watermark_dec_not_before = now + TSCHED_WATERMARK_VERIFY_AFTER_USEC;
+}
+
+/* Called from IO Context on unsuspend or from main thread when creating source */
+static void reset_watermark(struct userdata *u, size_t tsched_watermark, pa_sample_spec *ss,
+                            bool in_thread) {
+    u->tsched_watermark = pa_convert_size(tsched_watermark, ss, &u->source->sample_spec);
+
+    u->watermark_inc_step = pa_usec_to_bytes(TSCHED_WATERMARK_INC_STEP_USEC, &u->source->sample_spec);
+    u->watermark_dec_step = pa_usec_to_bytes(TSCHED_WATERMARK_DEC_STEP_USEC, &u->source->sample_spec);
+
+    u->watermark_inc_threshold = pa_usec_to_bytes_round_up(TSCHED_WATERMARK_INC_THRESHOLD_USEC, &u->source->sample_spec);
+    u->watermark_dec_threshold = pa_usec_to_bytes_round_up(TSCHED_WATERMARK_DEC_THRESHOLD_USEC, &u->source->sample_spec);
+
+    fix_min_sleep_wakeup(u);
+    fix_tsched_watermark(u);
+
+    if (in_thread)
+        pa_source_set_latency_range_within_thread(u->source,
+                                                  u->min_latency_ref,
+                                                  pa_bytes_to_usec(u->hwbuf_size, ss));
+    else {
+        pa_source_set_latency_range(u->source,
+                                    0,
+                                    pa_bytes_to_usec(u->hwbuf_size, ss));
+
+        /* work-around assert in pa_source_set_latency_within_thead,
+           keep track of min_latency and reuse it when
+           this routine is called from IO context */
+        u->min_latency_ref = u->source->thread_info.min_latency;
+    }
+
+    pa_log_info("Time scheduling watermark is %0.2fms",
+                (double) u->tsched_watermark_usec / PA_USEC_PER_MSEC);
+}
+
+static void hw_sleep_time(struct userdata *u, pa_usec_t *sleep_usec, pa_usec_t*process_usec) {
+    pa_usec_t wm, usec;
+
+    pa_assert(sleep_usec);
+    pa_assert(process_usec);
+
+    pa_assert(u);
+    pa_assert(u->use_tsched);
+
+    usec = pa_source_get_requested_latency_within_thread(u->source);
+
+    if (usec == (pa_usec_t) -1)
+        usec = pa_bytes_to_usec(u->hwbuf_size, &u->source->sample_spec);
+
+    wm = u->tsched_watermark_usec;
+
+    if (wm > usec)
+        wm = usec/2;
+
+    *sleep_usec = usec - wm;
+    *process_usec = wm;
+
+#ifdef DEBUG_TIMING
+    pa_log_debug("Buffer time: %lu ms; Sleep time: %lu ms; Process time: %lu ms",
+                 (unsigned long) (usec / PA_USEC_PER_MSEC),
+                 (unsigned long) (*sleep_usec / PA_USEC_PER_MSEC),
+                 (unsigned long) (*process_usec / PA_USEC_PER_MSEC));
+#endif
+}
+
+/* Reset smoother and counters */
+static void reset_vars(struct userdata *u) {
+
+    pa_smoother_reset(u->smoother, pa_rtclock_now(), true);
+    u->smoother_interval = SMOOTHER_MIN_INTERVAL;
+    u->last_smoother_update = 0;
+
+    u->read_count = 0;
+    u->first = true;
+}
+
+/* Called from IO context */
+static void close_pcm(struct userdata *u) {
+    pa_smoother_pause(u->smoother, pa_rtclock_now());
+
+    /* Let's suspend */
+    snd_pcm_close(u->pcm_handle);
+    u->pcm_handle = NULL;
+
+    if (u->alsa_rtpoll_item) {
+        pa_rtpoll_item_free(u->alsa_rtpoll_item);
+        u->alsa_rtpoll_item = NULL;
+    }
+}
+
+static int try_recover(struct userdata *u, const char *call, int err) {
+    pa_assert(u);
+    pa_assert(call);
+    pa_assert(err < 0);
+
+    pa_log_debug("%s: %s", call, pa_alsa_strerror(err));
+
+    pa_assert(err != -EAGAIN);
+
+    if (err == -EPIPE)
+        pa_log_debug("%s: Buffer overrun!", call);
+
+    if (err == -ESTRPIPE)
+        pa_log_debug("%s: System suspended!", call);
+
+    if ((err = snd_pcm_recover(u->pcm_handle, err, 1)) < 0) {
+        pa_log("%s: %s, trying to restart PCM", call, pa_alsa_strerror(err));
+
+        /* As a last measure, restart the PCM and inform the caller about it. */
+        close_pcm(u);
+        if (unsuspend(u, true) < 0)
+            return -1;
+
+        return 1;
+    }
+
+    reset_vars(u);
+    return 0;
+}
+
+static size_t check_left_to_record(struct userdata *u, size_t n_bytes, bool on_timeout) {
+    size_t left_to_record;
+    size_t rec_space = u->hwbuf_size - u->hwbuf_unused;
+    bool overrun = false;
+
+    /* We use <= instead of < for this check here because an overrun
+     * only happens after the last sample was processed, not already when
+     * it is removed from the buffer. This is particularly important
+     * when block transfer is used. */
+
+    if (n_bytes <= rec_space)
+        left_to_record = rec_space - n_bytes;
+    else {
+
+        /* We got a dropout. What a mess! */
+        left_to_record = 0;
+        overrun = true;
+
+#ifdef DEBUG_TIMING
+        PA_DEBUG_TRAP;
+#endif
+
+        if (pa_log_ratelimit(PA_LOG_INFO))
+            pa_log_info("Overrun!");
+    }
+
+#ifdef DEBUG_TIMING
+    pa_log_debug("%0.2f ms left to record", (double) pa_bytes_to_usec(left_to_record, &u->source->sample_spec) / PA_USEC_PER_MSEC);
+#endif
+
+    if (u->use_tsched) {
+        bool reset_not_before = true;
+
+        if (overrun || left_to_record < u->watermark_inc_threshold)
+            increase_watermark(u);
+        else if (left_to_record > u->watermark_dec_threshold) {
+            reset_not_before = false;
+
+            /* We decrease the watermark only if have actually
+             * been woken up by a timeout. If something else woke
+             * us up it's too easy to fulfill the deadlines... */
+
+            if (on_timeout)
+                decrease_watermark(u);
+        }
+
+        if (reset_not_before)
+            u->watermark_dec_not_before = 0;
+    }
+
+    return left_to_record;
+}
+
+static int mmap_read(struct userdata *u, pa_usec_t *sleep_usec, bool polled, bool on_timeout) {
+    bool work_done = false;
+    bool recovery_done = false;
+    pa_usec_t max_sleep_usec = 0, process_usec = 0;
+    size_t left_to_record;
+    unsigned j = 0;
+
+    pa_assert(u);
+    pa_source_assert_ref(u->source);
+
+    if (u->use_tsched)
+        hw_sleep_time(u, &max_sleep_usec, &process_usec);
+
+    for (;;) {
+        snd_pcm_sframes_t n;
+        size_t n_bytes;
+        int r;
+        bool after_avail = true;
+
+        if (PA_UNLIKELY((n = pa_alsa_safe_avail(u->pcm_handle, u->hwbuf_size, &u->source->sample_spec)) < 0)) {
+
+            recovery_done = true;
+            if ((r = try_recover(u, "snd_pcm_avail", (int) n)) >= 0)
+                continue;
+
+            return r;
+        }
+
+        n_bytes = (size_t) n * u->frame_size;
+
+#ifdef DEBUG_TIMING
+        pa_log_debug("avail: %lu", (unsigned long) n_bytes);
+#endif
+
+        left_to_record = check_left_to_record(u, n_bytes, on_timeout);
+        on_timeout = false;
+
+        if (u->use_tsched)
+            if (!polled &&
+                pa_bytes_to_usec(left_to_record, &u->source->sample_spec) > process_usec+max_sleep_usec/2) {
+#ifdef DEBUG_TIMING
+                pa_log_debug("Not reading, because too early.");
+#endif
+                break;
+            }
+
+        if (PA_UNLIKELY(n_bytes <= 0)) {
+
+            if (polled)
+                PA_ONCE_BEGIN {
+                    char *dn = pa_alsa_get_driver_name_by_pcm(u->pcm_handle);
+                    pa_log(_("ALSA woke us up to read new data from the device, but there was actually nothing to read.\n"
+                             "Most likely this is a bug in the ALSA driver '%s'. Please report this issue to the ALSA developers.\n"
+                             "We were woken up with POLLIN set -- however a subsequent snd_pcm_avail() returned 0 or another value < min_avail."),
+                           pa_strnull(dn));
+                    pa_xfree(dn);
+                } PA_ONCE_END;
+
+#ifdef DEBUG_TIMING
+            pa_log_debug("Not reading, because not necessary.");
+#endif
+            break;
+        }
+
+        if (++j > 10) {
+#ifdef DEBUG_TIMING
+            pa_log_debug("Not filling up, because already too many iterations.");
+#endif
+
+            break;
+        }
+
+        polled = false;
+
+#ifdef DEBUG_TIMING
+        pa_log_debug("Reading");
+#endif
+
+        for (;;) {
+            pa_memchunk chunk;
+            void *p;
+            int err;
+            const snd_pcm_channel_area_t *areas;
+            snd_pcm_uframes_t offset, frames;
+            snd_pcm_sframes_t sframes;
+
+            frames = (snd_pcm_uframes_t) (n_bytes / u->frame_size);
+/*             pa_log_debug("%lu frames to read", (unsigned long) frames); */
+
+            if (PA_UNLIKELY((err = pa_alsa_safe_mmap_begin(u->pcm_handle, &areas, &offset, &frames, u->hwbuf_size, &u->source->sample_spec)) < 0)) {
+
+                if (!after_avail && err == -EAGAIN)
+                    break;
+
+                recovery_done = true;
+                if ((r = try_recover(u, "snd_pcm_mmap_begin", err)) == 0)
+                    continue;
+
+                if (r == 1)
+                    break;
+
+                return r;
+            }
+
+            /* Make sure that if these memblocks need to be copied they will fit into one slot */
+            frames = PA_MIN(frames, u->frames_per_block);
+
+            if (!after_avail && frames == 0)
+                break;
+
+            pa_assert(frames > 0);
+            after_avail = false;
+
+            /* Check these are multiples of 8 bit */
+            pa_assert((areas[0].first & 7) == 0);
+            pa_assert((areas[0].step & 7) == 0);
+
+            /* We assume a single interleaved memory buffer */
+            pa_assert((areas[0].first >> 3) == 0);
+            pa_assert((areas[0].step >> 3) == u->frame_size);
+
+            p = (uint8_t*) areas[0].addr + (offset * u->frame_size);
+
+            chunk.memblock = pa_memblock_new_fixed(u->core->mempool, p, frames * u->frame_size, true);
+            chunk.length = pa_memblock_get_length(chunk.memblock);
+            chunk.index = 0;
+
+            pa_source_post(u->source, &chunk);
+            pa_memblock_unref_fixed(chunk.memblock);
+
+            if (PA_UNLIKELY((sframes = snd_pcm_mmap_commit(u->pcm_handle, offset, frames)) < 0)) {
+
+                recovery_done = true;
+                if ((r = try_recover(u, "snd_pcm_mmap_commit", (int) sframes)) == 0)
+                    continue;
+
+                if (r == 1)
+                    break;
+
+                return r;
+            }
+
+            work_done = true;
+
+            u->read_count += frames * u->frame_size;
+
+#ifdef DEBUG_TIMING
+            pa_log_debug("Read %lu bytes (of possible %lu bytes)", (unsigned long) (frames * u->frame_size), (unsigned long) n_bytes);
+#endif
+
+            if ((size_t) frames * u->frame_size >= n_bytes)
+                break;
+
+            n_bytes -= (size_t) frames * u->frame_size;
+        }
+    }
+
+    if (u->use_tsched) {
+        *sleep_usec = pa_bytes_to_usec(left_to_record, &u->source->sample_spec);
+        process_usec = u->tsched_watermark_usec;
+
+        if (*sleep_usec > process_usec)
+            *sleep_usec -= process_usec;
+        else
+            *sleep_usec = 0;
+
+        /* If the PCM was recovered, it may need restarting. Reduce the sleep time
+         * to 0 to ensure immediate restart. */
+        if (recovery_done)
+            *sleep_usec = 0;
+    }
+
+    return work_done ? 1 : 0;
+}
+
+static int unix_read(struct userdata *u, pa_usec_t *sleep_usec, bool polled, bool on_timeout) {
+    int work_done = false;
+    bool recovery_done = false;
+    pa_usec_t max_sleep_usec = 0, process_usec = 0;
+    size_t left_to_record;
+    unsigned j = 0;
+
+    pa_assert(u);
+    pa_source_assert_ref(u->source);
+
+    if (u->use_tsched)
+        hw_sleep_time(u, &max_sleep_usec, &process_usec);
+
+    for (;;) {
+        snd_pcm_sframes_t n;
+        size_t n_bytes;
+        int r;
+        bool after_avail = true;
+
+        if (PA_UNLIKELY((n = pa_alsa_safe_avail(u->pcm_handle, u->hwbuf_size, &u->source->sample_spec)) < 0)) {
+
+            recovery_done = true;
+            if ((r = try_recover(u, "snd_pcm_avail", (int) n)) >= 0)
+                continue;
+
+            return r;
+        }
+
+        n_bytes = (size_t) n * u->frame_size;
+        left_to_record = check_left_to_record(u, n_bytes, on_timeout);
+        on_timeout = false;
+
+        if (u->use_tsched)
+            if (!polled &&
+                pa_bytes_to_usec(left_to_record, &u->source->sample_spec) > process_usec+max_sleep_usec/2)
+                break;
+
+        if (PA_UNLIKELY(n_bytes <= 0)) {
+
+            if (polled)
+                PA_ONCE_BEGIN {
+                    char *dn = pa_alsa_get_driver_name_by_pcm(u->pcm_handle);
+                    pa_log(_("ALSA woke us up to read new data from the device, but there was actually nothing to read.\n"
+                             "Most likely this is a bug in the ALSA driver '%s'. Please report this issue to the ALSA developers.\n"
+                             "We were woken up with POLLIN set -- however a subsequent snd_pcm_avail() returned 0 or another value < min_avail."),
+                           pa_strnull(dn));
+                    pa_xfree(dn);
+                } PA_ONCE_END;
+
+            break;
+        }
+
+        if (++j > 10) {
+#ifdef DEBUG_TIMING
+            pa_log_debug("Not filling up, because already too many iterations.");
+#endif
+
+            break;
+        }
+
+        polled = false;
+
+        for (;;) {
+            void *p;
+            snd_pcm_sframes_t frames;
+            pa_memchunk chunk;
+
+            chunk.memblock = pa_memblock_new(u->core->mempool, (size_t) -1);
+
+            frames = (snd_pcm_sframes_t) (pa_memblock_get_length(chunk.memblock) / u->frame_size);
+
+            if (frames > (snd_pcm_sframes_t) (n_bytes/u->frame_size))
+                frames = (snd_pcm_sframes_t) (n_bytes/u->frame_size);
+
+/*             pa_log_debug("%lu frames to read", (unsigned long) n); */
+
+            p = pa_memblock_acquire(chunk.memblock);
+            frames = snd_pcm_readi(u->pcm_handle, (uint8_t*) p, (snd_pcm_uframes_t) frames);
+            pa_memblock_release(chunk.memblock);
+
+            if (PA_UNLIKELY(frames < 0)) {
+                pa_memblock_unref(chunk.memblock);
+
+                if (!after_avail && (int) frames == -EAGAIN)
+                    break;
+
+                recovery_done = true;
+                if ((r = try_recover(u, "snd_pcm_readi", (int) frames)) == 0)
+                    continue;
+
+                if (r == 1)
+                    break;
+
+                return r;
+            }
+
+            if (!after_avail && frames == 0) {
+                pa_memblock_unref(chunk.memblock);
+                break;
+            }
+
+            pa_assert(frames > 0);
+            after_avail = false;
+
+            chunk.index = 0;
+            chunk.length = (size_t) frames * u->frame_size;
+
+            pa_source_post(u->source, &chunk);
+            pa_memblock_unref(chunk.memblock);
+
+            work_done = true;
+
+            u->read_count += frames * u->frame_size;
+
+/*             pa_log_debug("read %lu frames", (unsigned long) frames); */
+
+            if ((size_t) frames * u->frame_size >= n_bytes)
+                break;
+
+            n_bytes -= (size_t) frames * u->frame_size;
+        }
+    }
+
+    if (u->use_tsched) {
+        *sleep_usec = pa_bytes_to_usec(left_to_record, &u->source->sample_spec);
+        process_usec = u->tsched_watermark_usec;
+
+        if (*sleep_usec > process_usec)
+            *sleep_usec -= process_usec;
+        else
+            *sleep_usec = 0;
+
+        /* If the PCM was recovered, it may need restarting. Reduce the sleep time
+         * to 0 to ensure immediate restart. */
+        if (recovery_done)
+            *sleep_usec = 0;
+    }
+
+    return work_done ? 1 : 0;
+}
+
+static void update_smoother(struct userdata *u) {
+    snd_pcm_sframes_t delay = 0;
+    uint64_t position;
+    int err;
+    pa_usec_t now1 = 0, now2;
+    snd_pcm_status_t *status;
+    snd_htimestamp_t htstamp = { 0, 0 };
+
+    snd_pcm_status_alloca(&status);
+
+    pa_assert(u);
+    pa_assert(u->pcm_handle);
+
+    /* Let's update the time smoother */
+
+    if (PA_UNLIKELY((err = pa_alsa_safe_delay(u->pcm_handle, status, &delay, u->hwbuf_size, &u->source->sample_spec, true)) < 0)) {
+        pa_log_warn("Failed to get delay: %s", pa_alsa_strerror(err));
+        return;
+    }
+
+    snd_pcm_status_get_htstamp(status, &htstamp);
+    now1 = pa_timespec_load(&htstamp);
+
+    /* Hmm, if the timestamp is 0, then it wasn't set and we take the current time */
+    if (now1 <= 0)
+        now1 = pa_rtclock_now();
+
+    /* check if the time since the last update is bigger than the interval */
+    if (u->last_smoother_update > 0)
+        if (u->last_smoother_update + u->smoother_interval > now1)
+            return;
+
+    position = u->read_count + ((uint64_t) delay * (uint64_t) u->frame_size);
+    now2 = pa_bytes_to_usec(position, &u->source->sample_spec);
+
+    pa_smoother_put(u->smoother, now1, now2);
+
+    u->last_smoother_update = now1;
+    /* exponentially increase the update interval up to the MAX limit */
+    u->smoother_interval = PA_MIN (u->smoother_interval * 2, SMOOTHER_MAX_INTERVAL);
+}
+
+static int64_t source_get_latency(struct userdata *u) {
+    int64_t delay;
+    pa_usec_t now1, now2;
+
+    pa_assert(u);
+
+    now1 = pa_rtclock_now();
+    now2 = pa_smoother_get(u->smoother, now1);
+
+    delay = (int64_t) now2 - (int64_t) pa_bytes_to_usec(u->read_count, &u->source->sample_spec);
+
+    return delay;
+}
+
+static int build_pollfd(struct userdata *u) {
+    pa_assert(u);
+    pa_assert(u->pcm_handle);
+
+    if (u->alsa_rtpoll_item)
+        pa_rtpoll_item_free(u->alsa_rtpoll_item);
+
+    if (!(u->alsa_rtpoll_item = pa_alsa_build_pollfd(u->pcm_handle, u->rtpoll)))
+        return -1;
+
+    return 0;
+}
+
+/* Called from IO context */
+static void suspend(struct userdata *u) {
+    pa_assert(u);
+
+    /* PCM may have been invalidated due to device failure.
+     * In that case, there is nothing to do. */
+    if (!u->pcm_handle)
+        return;
+
+    /* Close PCM device */
+    close_pcm(u);
+
+    pa_log_info("Device suspended...");
+}
+
+/* Called from IO context */
+static int update_sw_params(struct userdata *u) {
+    snd_pcm_uframes_t avail_min;
+    int err;
+
+    pa_assert(u);
+
+    /* Use the full buffer if no one asked us for anything specific */
+    u->hwbuf_unused = 0;
+
+    if (u->use_tsched) {
+        pa_usec_t latency;
+
+        if ((latency = pa_source_get_requested_latency_within_thread(u->source)) != (pa_usec_t) -1) {
+            size_t b;
+
+            pa_log_debug("latency set to %0.2fms", (double) latency / PA_USEC_PER_MSEC);
+
+            b = pa_usec_to_bytes(latency, &u->source->sample_spec);
+
+            /* We need at least one sample in our buffer */
+
+            if (PA_UNLIKELY(b < u->frame_size))
+                b = u->frame_size;
+
+            u->hwbuf_unused = PA_LIKELY(b < u->hwbuf_size) ? (u->hwbuf_size - b) : 0;
+        }
+
+        fix_min_sleep_wakeup(u);
+        fix_tsched_watermark(u);
+    }
+
+    pa_log_debug("hwbuf_unused=%lu", (unsigned long) u->hwbuf_unused);
+
+    avail_min = 1;
+
+    if (u->use_tsched) {
+        pa_usec_t sleep_usec, process_usec;
+
+        hw_sleep_time(u, &sleep_usec, &process_usec);
+        avail_min += pa_usec_to_bytes(sleep_usec, &u->source->sample_spec) / u->frame_size;
+    }
+
+    pa_log_debug("setting avail_min=%lu", (unsigned long) avail_min);
+
+    if ((err = pa_alsa_set_sw_params(u->pcm_handle, avail_min, !u->use_tsched)) < 0) {
+        pa_log("Failed to set software parameters: %s", pa_alsa_strerror(err));
+        return err;
+    }
+
+    return 0;
+}
+
+/* Called from IO Context on unsuspend */
+static void update_size(struct userdata *u, pa_sample_spec *ss) {
+    pa_assert(u);
+    pa_assert(ss);
+
+    u->frame_size = pa_frame_size(ss);
+    u->frames_per_block = pa_mempool_block_size_max(u->core->mempool) / u->frame_size;
+
+    /* use initial values including module arguments */
+    u->fragment_size = u->initial_info.fragment_size;
+    u->hwbuf_size = u->initial_info.nfrags * u->fragment_size;
+    u->tsched_size = u->initial_info.tsched_size;
+    u->tsched_watermark = u->initial_info.tsched_watermark;
+
+    u->tsched_watermark_ref = u->tsched_watermark;
+
+    pa_log_info("Updated frame_size %zu, frames_per_block %lu, fragment_size %zu, hwbuf_size %zu, tsched(size %zu, watermark %zu)",
+                u->frame_size, (unsigned long) u->frames_per_block, u->fragment_size, u->hwbuf_size, u->tsched_size, u->tsched_watermark);
+}
+
+/* Called from IO context */
+static int unsuspend(struct userdata *u, bool recovering) {
+    pa_sample_spec ss;
+    int err, i;
+    bool b, d;
+    snd_pcm_uframes_t period_frames, buffer_frames;
+    snd_pcm_uframes_t tsched_frames = 0;
+    bool frame_size_changed = false;
+
+    pa_assert(u);
+    pa_assert(!u->pcm_handle);
+
+    pa_log_info("Trying resume...");
+
+    /*
+     * On some machines, during the system suspend and resume, the thread_func could receive
+     * POLLERR events before the dev nodes in /dev/snd/ are accessible, and thread_func calls
+     * the unsuspend() to try to recover the PCM, this will make the snd_pcm_open() fail, here
+     * we add msleep and retry to make sure those nodes are accessible.
+     */
+    for (i = 0; i < 4; i++) {
+	if ((err = snd_pcm_open(&u->pcm_handle, u->device_name, SND_PCM_STREAM_CAPTURE,
+				SND_PCM_NONBLOCK|
+				SND_PCM_NO_AUTO_RESAMPLE|
+				SND_PCM_NO_AUTO_CHANNELS|
+				SND_PCM_NO_AUTO_FORMAT)) < 0 && recovering)
+	    pa_msleep(25);
+	else
+	    break;
+    }
+
+    if (err < 0) {
+	pa_log("Error opening PCM device %s: %s", u->device_name, pa_alsa_strerror(err));
+        goto fail;
+    }
+
+    if (pa_frame_size(&u->source->sample_spec) != u->frame_size) {
+        update_size(u, &u->source->sample_spec);
+        tsched_frames = u->tsched_size / u->frame_size;
+        frame_size_changed = true;
+    }
+
+    ss = u->source->sample_spec;
+    period_frames = u->fragment_size / u->frame_size;
+    buffer_frames = u->hwbuf_size / u->frame_size;
+    b = u->use_mmap;
+    d = u->use_tsched;
+
+    if ((err = pa_alsa_set_hw_params(u->pcm_handle, &ss, &period_frames, &buffer_frames, tsched_frames, &b, &d, true)) < 0) {
+        pa_log("Failed to set hardware parameters: %s", pa_alsa_strerror(err));
+        goto fail;
+    }
+
+    if (b != u->use_mmap || d != u->use_tsched) {
+        pa_log_warn("Resume failed, couldn't get original access mode.");
+        goto fail;
+    }
+
+    if (!pa_sample_spec_equal(&ss, &u->source->sample_spec)) {
+        pa_log_warn("Resume failed, couldn't restore original sample settings.");
+        goto fail;
+    }
+
+    if (frame_size_changed) {
+        u->fragment_size = (size_t)(period_frames * u->frame_size);
+        u->hwbuf_size = (size_t)(buffer_frames * u->frame_size);
+        pa_proplist_setf(u->source->proplist, PA_PROP_DEVICE_BUFFERING_BUFFER_SIZE, "%zu", u->hwbuf_size);
+        pa_proplist_setf(u->source->proplist, PA_PROP_DEVICE_BUFFERING_FRAGMENT_SIZE, "%zu", u->fragment_size);
+
+    } else if (period_frames * u->frame_size != u->fragment_size ||
+                buffer_frames * u->frame_size != u->hwbuf_size) {
+        pa_log_warn("Resume failed, couldn't restore original fragment settings. (Old: %zu/%zu, New %lu/%lu)",
+                    u->hwbuf_size, u->fragment_size,
+                    (unsigned long) buffer_frames * u->frame_size, (unsigned long) period_frames * u->frame_size);
+        goto fail;
+    }
+
+    if (update_sw_params(u) < 0)
+        goto fail;
+
+    if (build_pollfd(u) < 0)
+        goto fail;
+
+    /* FIXME: We need to reload the volume somehow */
+
+    reset_vars(u);
+
+    /* reset the watermark to the value defined when source was created */
+    if (u->use_tsched && !recovering)
+        reset_watermark(u, u->tsched_watermark_ref, &u->source->sample_spec, true);
+
+    pa_log_info("Resumed successfully...");
+
+    return 0;
+
+fail:
+    if (u->pcm_handle) {
+        snd_pcm_close(u->pcm_handle);
+        u->pcm_handle = NULL;
+    }
+
+    return -PA_ERR_IO;
+}
+
+/* Called from the IO thread or the main thread depending on whether deferred
+ * volume is enabled or not (with deferred volume all mixer handling is done
+ * from the IO thread).
+ *
+ * Sets the mixer settings to match the current source and port state (the port
+ * is given as an argument, because active_port may still point to the old
+ * port, if we're switching ports). */
+static void sync_mixer(struct userdata *u, pa_device_port *port) {
+    pa_alsa_setting *setting = NULL;
+
+    pa_assert(u);
+
+    if (!u->mixer_path)
+        return;
+
+    /* port may be NULL, because if we use a synthesized mixer path, then the
+     * source has no ports. */
+    if (port && !u->ucm_context) {
+        pa_alsa_port_data *data;
+
+        data = PA_DEVICE_PORT_DATA(port);
+        setting = data->setting;
+    }
+
+    pa_alsa_path_select(u->mixer_path, setting, u->mixer_handle, u->source->muted);
+
+    if (u->source->set_mute)
+        u->source->set_mute(u->source);
+    if (u->source->flags & PA_SOURCE_DEFERRED_VOLUME) {
+        if (u->source->write_volume)
+            u->source->write_volume(u->source);
+    } else {
+        if (u->source->set_volume)
+            u->source->set_volume(u->source);
+    }
+}
+
+/* Called from IO context */
+static int source_process_msg(pa_msgobject *o, int code, void *data, int64_t offset, pa_memchunk *chunk) {
+    struct userdata *u = PA_SOURCE(o)->userdata;
+
+    switch (code) {
+
+        case PA_SOURCE_MESSAGE_GET_LATENCY: {
+            int64_t r = 0;
+
+            if (u->pcm_handle)
+                r = source_get_latency(u);
+
+            *((int64_t*) data) = r;
+
+            return 0;
+        }
+
+        case SOURCE_MESSAGE_SYNC_MIXER: {
+            pa_device_port *port = data;
+
+            sync_mixer(u, port);
+            return 0;
+        }
+    }
+
+    return pa_source_process_msg(o, code, data, offset, chunk);
+}
+
+/* Called from main context */
+static int source_set_state_in_main_thread_cb(pa_source *s, pa_source_state_t new_state, pa_suspend_cause_t new_suspend_cause) {
+    pa_source_state_t old_state;
+    struct userdata *u;
+
+    pa_source_assert_ref(s);
+    pa_assert_se(u = s->userdata);
+
+    /* When our session becomes active, we need to sync the mixer, because
+     * another user may have changed the mixer settings.
+     *
+     * If deferred volume is enabled, the syncing is done in the
+     * set_state_in_io_thread() callback instead. */
+    if (!(s->flags & PA_SOURCE_DEFERRED_VOLUME)
+            && (s->suspend_cause & PA_SUSPEND_SESSION)
+            && !(new_suspend_cause & PA_SUSPEND_SESSION))
+        sync_mixer(u, s->active_port);
+
+    old_state = u->source->state;
+
+    if (PA_SOURCE_IS_OPENED(old_state) && new_state == PA_SOURCE_SUSPENDED)
+        reserve_done(u);
+    else if (old_state == PA_SOURCE_SUSPENDED && PA_SOURCE_IS_OPENED(new_state))
+        if (reserve_init(u, u->device_name) < 0)
+            return -PA_ERR_BUSY;
+
+    return 0;
+}
+
+/* Called from the IO thread. */
+static int source_set_state_in_io_thread_cb(pa_source *s, pa_source_state_t new_state, pa_suspend_cause_t new_suspend_cause) {
+    struct userdata *u;
+
+    pa_assert(s);
+    pa_assert_se(u = s->userdata);
+
+    /* When our session becomes active, we need to sync the mixer, because
+     * another user may have changed the mixer settings.
+     *
+     * If deferred volume is disabled, the syncing is done in the
+     * set_state_in_main_thread() callback instead. */
+    if ((s->flags & PA_SOURCE_DEFERRED_VOLUME)
+            && (s->suspend_cause & PA_SUSPEND_SESSION)
+            && !(new_suspend_cause & PA_SUSPEND_SESSION))
+        sync_mixer(u, s->active_port);
+
+    /* It may be that only the suspend cause is changing, in which case there's
+     * nothing more to do. */
+    if (new_state == s->thread_info.state)
+        return 0;
+
+    switch (new_state) {
+
+        case PA_SOURCE_SUSPENDED: {
+            pa_assert(PA_SOURCE_IS_OPENED(s->thread_info.state));
+
+            suspend(u);
+
+            break;
+        }
+
+        case PA_SOURCE_IDLE:
+        case PA_SOURCE_RUNNING: {
+            int r;
+
+            if (s->thread_info.state == PA_SOURCE_INIT) {
+                if (build_pollfd(u) < 0)
+                    /* FIXME: This will cause an assertion failure, because
+                     * with the current design pa_source_put() is not allowed
+                     * to fail and pa_source_put() has no fallback code that
+                     * would start the source suspended if opening the device
+                     * fails. */
+                    return -PA_ERR_IO;
+            }
+
+            if (s->thread_info.state == PA_SOURCE_SUSPENDED) {
+                if ((r = unsuspend(u, false)) < 0)
+                    return r;
+            }
+
+            break;
+        }
+
+        case PA_SOURCE_UNLINKED:
+        case PA_SOURCE_INIT:
+        case PA_SOURCE_INVALID_STATE:
+            ;
+    }
+
+    return 0;
+}
+
+static int ctl_mixer_callback(snd_mixer_elem_t *elem, unsigned int mask) {
+    struct userdata *u = snd_mixer_elem_get_callback_private(elem);
+
+    pa_assert(u);
+    pa_assert(u->mixer_handle);
+
+    if (mask == SND_CTL_EVENT_MASK_REMOVE)
+        return 0;
+
+    if (!PA_SOURCE_IS_LINKED(u->source->state))
+        return 0;
+
+    if (u->source->suspend_cause & PA_SUSPEND_SESSION)
+        return 0;
+
+    if (mask & SND_CTL_EVENT_MASK_VALUE) {
+        pa_source_get_volume(u->source, true);
+        pa_source_get_mute(u->source, true);
+    }
+
+    return 0;
+}
+
+static int io_mixer_callback(snd_mixer_elem_t *elem, unsigned int mask) {
+    struct userdata *u = snd_mixer_elem_get_callback_private(elem);
+
+    pa_assert(u);
+    pa_assert(u->mixer_handle);
+
+    if (mask == SND_CTL_EVENT_MASK_REMOVE)
+        return 0;
+
+    if (u->source->suspend_cause & PA_SUSPEND_SESSION)
+        return 0;
+
+    if (mask & SND_CTL_EVENT_MASK_VALUE)
+        pa_source_update_volume_and_mute(u->source);
+
+    return 0;
+}
+
+static void source_get_volume_cb(pa_source *s) {
+    struct userdata *u = s->userdata;
+    pa_cvolume r;
+    char volume_buf[PA_CVOLUME_SNPRINT_VERBOSE_MAX];
+
+    pa_assert(u);
+    pa_assert(u->mixer_path);
+    pa_assert(u->mixer_handle);
+
+    if (pa_alsa_path_get_volume(u->mixer_path, u->mixer_handle, &s->channel_map, &r) < 0)
+        return;
+
+    /* Shift down by the base volume, so that 0dB becomes maximum volume */
+    pa_sw_cvolume_multiply_scalar(&r, &r, s->base_volume);
+
+    pa_log_debug("Read hardware volume: %s",
+                 pa_cvolume_snprint_verbose(volume_buf, sizeof(volume_buf), &r, &s->channel_map, u->mixer_path->has_dB));
+
+    if (pa_cvolume_equal(&u->hardware_volume, &r))
+        return;
+
+    s->real_volume = u->hardware_volume = r;
+
+    /* Hmm, so the hardware volume changed, let's reset our software volume */
+    if (u->mixer_path->has_dB)
+        pa_source_set_soft_volume(s, NULL);
+}
+
+static void source_set_volume_cb(pa_source *s) {
+    struct userdata *u = s->userdata;
+    pa_cvolume r;
+    char volume_buf[PA_CVOLUME_SNPRINT_VERBOSE_MAX];
+    bool deferred_volume = !!(s->flags & PA_SOURCE_DEFERRED_VOLUME);
+
+    pa_assert(u);
+    pa_assert(u->mixer_path);
+    pa_assert(u->mixer_handle);
+
+    /* Shift up by the base volume */
+    pa_sw_cvolume_divide_scalar(&r, &s->real_volume, s->base_volume);
+
+    if (pa_alsa_path_set_volume(u->mixer_path, u->mixer_handle, &s->channel_map, &r, deferred_volume, !deferred_volume) < 0)
+        return;
+
+    /* Shift down by the base volume, so that 0dB becomes maximum volume */
+    pa_sw_cvolume_multiply_scalar(&r, &r, s->base_volume);
+
+    u->hardware_volume = r;
+
+    if (u->mixer_path->has_dB) {
+        pa_cvolume new_soft_volume;
+        bool accurate_enough;
+
+        /* Match exactly what the user requested by software */
+        pa_sw_cvolume_divide(&new_soft_volume, &s->real_volume, &u->hardware_volume);
+
+        /* If the adjustment to do in software is only minimal we
+         * can skip it. That saves us CPU at the expense of a bit of
+         * accuracy */
+        accurate_enough =
+            (pa_cvolume_min(&new_soft_volume) >= (PA_VOLUME_NORM - VOLUME_ACCURACY)) &&
+            (pa_cvolume_max(&new_soft_volume) <= (PA_VOLUME_NORM + VOLUME_ACCURACY));
+
+        pa_log_debug("Requested volume: %s",
+                     pa_cvolume_snprint_verbose(volume_buf, sizeof(volume_buf), &s->real_volume, &s->channel_map, true));
+        pa_log_debug("Got hardware volume: %s",
+                     pa_cvolume_snprint_verbose(volume_buf, sizeof(volume_buf), &u->hardware_volume, &s->channel_map, true));
+        pa_log_debug("Calculated software volume: %s (accurate-enough=%s)",
+                     pa_cvolume_snprint_verbose(volume_buf, sizeof(volume_buf), &new_soft_volume, &s->channel_map, true),
+                     pa_yes_no(accurate_enough));
+
+        if (!accurate_enough)
+            s->soft_volume = new_soft_volume;
+
+    } else {
+        pa_log_debug("Wrote hardware volume: %s",
+                     pa_cvolume_snprint_verbose(volume_buf, sizeof(volume_buf), &r, &s->channel_map, false));
+
+        /* We can't match exactly what the user requested, hence let's
+         * at least tell the user about it */
+
+        s->real_volume = r;
+    }
+}
+
+static void source_write_volume_cb(pa_source *s) {
+    struct userdata *u = s->userdata;
+    pa_cvolume hw_vol = s->thread_info.current_hw_volume;
+
+    pa_assert(u);
+    pa_assert(u->mixer_path);
+    pa_assert(u->mixer_handle);
+    pa_assert(s->flags & PA_SOURCE_DEFERRED_VOLUME);
+
+    /* Shift up by the base volume */
+    pa_sw_cvolume_divide_scalar(&hw_vol, &hw_vol, s->base_volume);
+
+    if (pa_alsa_path_set_volume(u->mixer_path, u->mixer_handle, &s->channel_map, &hw_vol, true, true) < 0)
+        pa_log_error("Writing HW volume failed");
+    else {
+        pa_cvolume tmp_vol;
+        bool accurate_enough;
+
+        /* Shift down by the base volume, so that 0dB becomes maximum volume */
+        pa_sw_cvolume_multiply_scalar(&hw_vol, &hw_vol, s->base_volume);
+
+        pa_sw_cvolume_divide(&tmp_vol, &hw_vol, &s->thread_info.current_hw_volume);
+        accurate_enough =
+            (pa_cvolume_min(&tmp_vol) >= (PA_VOLUME_NORM - VOLUME_ACCURACY)) &&
+            (pa_cvolume_max(&tmp_vol) <= (PA_VOLUME_NORM + VOLUME_ACCURACY));
+
+        if (!accurate_enough) {
+            char volume_buf[2][PA_CVOLUME_SNPRINT_VERBOSE_MAX];
+
+            pa_log_debug("Written HW volume did not match with the request: %s (request) != %s",
+                         pa_cvolume_snprint_verbose(volume_buf[0],
+                                                    sizeof(volume_buf[0]),
+                                                    &s->thread_info.current_hw_volume,
+                                                    &s->channel_map,
+                                                    true),
+                         pa_cvolume_snprint_verbose(volume_buf[1], sizeof(volume_buf[1]), &hw_vol, &s->channel_map, true));
+        }
+    }
+}
+
+static int source_get_mute_cb(pa_source *s, bool *mute) {
+    struct userdata *u = s->userdata;
+
+    pa_assert(u);
+    pa_assert(u->mixer_path);
+    pa_assert(u->mixer_handle);
+
+    if (pa_alsa_path_get_mute(u->mixer_path, u->mixer_handle, mute) < 0)
+        return -1;
+
+    return 0;
+}
+
+static void source_set_mute_cb(pa_source *s) {
+    struct userdata *u = s->userdata;
+
+    pa_assert(u);
+    pa_assert(u->mixer_path);
+    pa_assert(u->mixer_handle);
+
+    pa_alsa_path_set_mute(u->mixer_path, u->mixer_handle, s->muted);
+}
+
+static void mixer_volume_init(struct userdata *u) {
+    pa_assert(u);
+
+    if (!u->mixer_path || !u->mixer_path->has_volume) {
+        pa_source_set_write_volume_callback(u->source, NULL);
+        pa_source_set_get_volume_callback(u->source, NULL);
+        pa_source_set_set_volume_callback(u->source, NULL);
+
+        pa_log_info("Driver does not support hardware volume control, falling back to software volume control.");
+    } else {
+        pa_source_set_get_volume_callback(u->source, source_get_volume_cb);
+        pa_source_set_set_volume_callback(u->source, source_set_volume_cb);
+
+        if (u->mixer_path->has_dB && u->deferred_volume) {
+            pa_source_set_write_volume_callback(u->source, source_write_volume_cb);
+            pa_log_info("Successfully enabled deferred volume.");
+        } else
+            pa_source_set_write_volume_callback(u->source, NULL);
+
+        if (u->mixer_path->has_dB) {
+            pa_source_enable_decibel_volume(u->source, true);
+            pa_log_info("Hardware volume ranges from %0.2f dB to %0.2f dB.", u->mixer_path->min_dB, u->mixer_path->max_dB);
+
+            u->source->base_volume = pa_sw_volume_from_dB(-u->mixer_path->max_dB);
+            u->source->n_volume_steps = PA_VOLUME_NORM+1;
+
+            pa_log_info("Fixing base volume to %0.2f dB", pa_sw_volume_to_dB(u->source->base_volume));
+        } else {
+            pa_source_enable_decibel_volume(u->source, false);
+            pa_log_info("Hardware volume ranges from %li to %li.", u->mixer_path->min_volume, u->mixer_path->max_volume);
+
+            u->source->base_volume = PA_VOLUME_NORM;
+            u->source->n_volume_steps = u->mixer_path->max_volume - u->mixer_path->min_volume + 1;
+        }
+
+        pa_log_info("Using hardware volume control. Hardware dB scale %s.", u->mixer_path->has_dB ? "supported" : "not supported");
+    }
+
+    if (!u->mixer_path || !u->mixer_path->has_mute) {
+        pa_source_set_get_mute_callback(u->source, NULL);
+        pa_source_set_set_mute_callback(u->source, NULL);
+        pa_log_info("Driver does not support hardware mute control, falling back to software mute control.");
+    } else {
+        pa_source_set_get_mute_callback(u->source, source_get_mute_cb);
+        pa_source_set_set_mute_callback(u->source, source_set_mute_cb);
+        pa_log_info("Using hardware mute control.");
+    }
+}
+
+static int source_set_port_ucm_cb(pa_source *s, pa_device_port *p) {
+    struct userdata *u = s->userdata;
+    pa_alsa_ucm_port_data *data;
+
+    pa_assert(u);
+    pa_assert(p);
+    pa_assert(u->ucm_context);
+
+    data = PA_DEVICE_PORT_DATA(p);
+    u->mixer_path = data->path;
+    mixer_volume_init(u);
+
+    if (s->flags & PA_SOURCE_DEFERRED_VOLUME)
+        pa_asyncmsgq_send(u->source->asyncmsgq, PA_MSGOBJECT(u->source), SOURCE_MESSAGE_SYNC_MIXER, p, 0, NULL);
+    else
+        sync_mixer(u, p);
+
+    return pa_alsa_ucm_set_port(u->ucm_context, p, false);
+}
+
+static int source_set_port_cb(pa_source *s, pa_device_port *p) {
+    struct userdata *u = s->userdata;
+    pa_alsa_port_data *data;
+
+    pa_assert(u);
+    pa_assert(p);
+    pa_assert(u->mixer_handle);
+    pa_assert(!u->ucm_context);
+
+    data = PA_DEVICE_PORT_DATA(p);
+    pa_assert_se(u->mixer_path = data->path);
+    mixer_volume_init(u);
+
+    if (s->flags & PA_SOURCE_DEFERRED_VOLUME)
+        pa_asyncmsgq_send(u->source->asyncmsgq, PA_MSGOBJECT(u->source), SOURCE_MESSAGE_SYNC_MIXER, p, 0, NULL);
+    else
+        sync_mixer(u, p);
+
+    return 0;
+}
+
+static void source_update_requested_latency_cb(pa_source *s) {
+    struct userdata *u = s->userdata;
+    pa_assert(u);
+    pa_assert(u->use_tsched); /* only when timer scheduling is used
+                               * we can dynamically adjust the
+                               * latency */
+
+    if (!u->pcm_handle)
+        return;
+
+    update_sw_params(u);
+}
+
+static void source_reconfigure_cb(pa_source *s, pa_sample_spec *spec, bool passthrough) {
+    struct userdata *u = s->userdata;
+    int i;
+    bool format_supported = false;
+    bool rate_supported = false;
+
+    pa_assert(u);
+
+    for (i = 0; u->supported_formats[i] != PA_SAMPLE_MAX; i++) {
+        if (u->supported_formats[i] == spec->format) {
+            pa_source_set_sample_format(u->source, spec->format);
+            format_supported = true;
+            break;
+        }
+    }
+
+    if (!format_supported) {
+        pa_log_info("Source does not support sample format of %s, set it to a verified value",
+                    pa_sample_format_to_string(spec->format));
+        pa_source_set_sample_format(u->source, u->verified_sample_spec.format);
+    }
+
+    for (i = 0; u->supported_rates[i]; i++) {
+        if (u->supported_rates[i] == spec->rate) {
+            pa_source_set_sample_rate(u->source, spec->rate);
+            rate_supported = true;
+            break;
+        }
+    }
+
+    if (!rate_supported) {
+        pa_log_info("Source does not support sample rate of %u, set it to a verfied value", spec->rate);
+        pa_source_set_sample_rate(u->source, u->verified_sample_spec.rate);
+    }
+}
+
+static void thread_func(void *userdata) {
+    struct userdata *u = userdata;
+    unsigned short revents = 0;
+
+    pa_assert(u);
+
+    pa_log_debug("Thread starting up");
+
+    if (u->core->realtime_scheduling)
+        pa_thread_make_realtime(u->core->realtime_priority);
+
+    pa_thread_mq_install(&u->thread_mq);
+
+    for (;;) {
+        int ret;
+        pa_usec_t rtpoll_sleep = 0, real_sleep;
+
+#ifdef DEBUG_TIMING
+        pa_log_debug("Loop");
+#endif
+
+        /* Read some data and pass it to the sources */
+        if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
+            int work_done;
+            pa_usec_t sleep_usec = 0;
+            bool on_timeout = pa_rtpoll_timer_elapsed(u->rtpoll);
+
+            if (u->first) {
+                pa_log_info("Starting capture.");
+                snd_pcm_start(u->pcm_handle);
+
+                pa_smoother_resume(u->smoother, pa_rtclock_now(), true);
+
+                u->first = false;
+            }
+
+            if (u->use_mmap)
+                work_done = mmap_read(u, &sleep_usec, revents & POLLIN, on_timeout);
+            else
+                work_done = unix_read(u, &sleep_usec, revents & POLLIN, on_timeout);
+
+            if (work_done < 0)
+                goto fail;
+
+/*             pa_log_debug("work_done = %i", work_done); */
+
+            if (work_done)
+                update_smoother(u);
+
+            if (u->use_tsched) {
+                pa_usec_t cusec;
+
+                /* OK, the capture buffer is now empty, let's
+                 * calculate when to wake up next */
+
+/*                 pa_log_debug("Waking up in %0.2fms (sound card clock).", (double) sleep_usec / PA_USEC_PER_MSEC); */
+
+                /* Convert from the sound card time domain to the
+                 * system time domain */
+                cusec = pa_smoother_translate(u->smoother, pa_rtclock_now(), sleep_usec);
+
+/*                 pa_log_debug("Waking up in %0.2fms (system clock).", (double) cusec / PA_USEC_PER_MSEC); */
+
+                /* We don't trust the conversion, so we wake up whatever comes first */
+                rtpoll_sleep = PA_MIN(sleep_usec, cusec);
+            }
+        }
+
+        if (u->source->flags & PA_SOURCE_DEFERRED_VOLUME) {
+            pa_usec_t volume_sleep;
+            pa_source_volume_change_apply(u->source, &volume_sleep);
+            if (volume_sleep > 0) {
+                if (rtpoll_sleep > 0)
+                    rtpoll_sleep = PA_MIN(volume_sleep, rtpoll_sleep);
+                else
+                    rtpoll_sleep = volume_sleep;
+            }
+        }
+
+        if (rtpoll_sleep > 0) {
+            pa_rtpoll_set_timer_relative(u->rtpoll, rtpoll_sleep);
+            real_sleep = pa_rtclock_now();
+        }
+        else
+            pa_rtpoll_set_timer_disabled(u->rtpoll);
+
+        /* Hmm, nothing to do. Let's sleep */
+        if ((ret = pa_rtpoll_run(u->rtpoll)) < 0)
+            goto fail;
+
+        if (rtpoll_sleep > 0) {
+            real_sleep = pa_rtclock_now() - real_sleep;
+#ifdef DEBUG_TIMING
+            pa_log_debug("Expected sleep: %0.2fms, real sleep: %0.2fms (diff %0.2f ms)",
+                (double) rtpoll_sleep / PA_USEC_PER_MSEC, (double) real_sleep / PA_USEC_PER_MSEC,
+                (double) ((int64_t) real_sleep - (int64_t) rtpoll_sleep) / PA_USEC_PER_MSEC);
+#endif
+            if (u->use_tsched && real_sleep > rtpoll_sleep + u->tsched_watermark_usec)
+                pa_log_info("Scheduling delay of %0.2f ms > %0.2f ms, you might want to investigate this to improve latency...",
+                    (double) (real_sleep - rtpoll_sleep) / PA_USEC_PER_MSEC,
+                    (double) (u->tsched_watermark_usec) / PA_USEC_PER_MSEC);
+        }
+
+        if (u->source->flags & PA_SOURCE_DEFERRED_VOLUME)
+            pa_source_volume_change_apply(u->source, NULL);
+
+        if (ret == 0)
+            goto finish;
+
+        /* Tell ALSA about this and process its response */
+        if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
+            struct pollfd *pollfd;
+            int err;
+            unsigned n;
+
+            pollfd = pa_rtpoll_item_get_pollfd(u->alsa_rtpoll_item, &n);
+
+            if ((err = snd_pcm_poll_descriptors_revents(u->pcm_handle, pollfd, n, &revents)) < 0) {
+                pa_log("snd_pcm_poll_descriptors_revents() failed: %s", pa_alsa_strerror(err));
+                goto fail;
+            }
+
+            if (revents & ~POLLIN) {
+                if ((err = pa_alsa_recover_from_poll(u->pcm_handle, revents)) < 0)
+                    goto fail;
+
+                /* Stream needs to be restarted */
+                if (err == 1) {
+                    close_pcm(u);
+                    if (unsuspend(u, true) < 0)
+                        goto fail;
+                } else
+                    reset_vars(u);
+
+                revents = 0;
+            } else if (revents && u->use_tsched && pa_log_ratelimit(PA_LOG_DEBUG))
+                pa_log_debug("Wakeup from ALSA!");
+
+        } else
+            revents = 0;
+    }
+
+fail:
+    /* If this was no regular exit from the loop we have to continue
+     * processing messages until we received PA_MESSAGE_SHUTDOWN */
+    pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
+    pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
+
+finish:
+    pa_log_debug("Thread shutting down");
+}
+
+static void set_source_name(pa_source_new_data *data, pa_modargs *ma, const char *device_id, const char *device_name, pa_alsa_mapping *mapping) {
+    const char *n;
+    char *t;
+
+    pa_assert(data);
+    pa_assert(ma);
+    pa_assert(device_name);
+
+    if ((n = pa_modargs_get_value(ma, "source_name", NULL))) {
+        pa_source_new_data_set_name(data, n);
+        data->namereg_fail = true;
+        return;
+    }
+
+    if ((n = pa_modargs_get_value(ma, "name", NULL)))
+        data->namereg_fail = true;
+    else {
+        n = device_id ? device_id : device_name;
+        data->namereg_fail = false;
+    }
+
+    if (mapping)
+        t = pa_sprintf_malloc("alsa_input.%s.%s", n, mapping->name);
+    else
+        t = pa_sprintf_malloc("alsa_input.%s", n);
+
+    pa_source_new_data_set_name(data, t);
+    pa_xfree(t);
+}
+
+static void find_mixer(struct userdata *u, pa_alsa_mapping *mapping, const char *element, bool ignore_dB) {
+    const char *mdev;
+
+    if (!mapping && !element)
+        return;
+
+    if (!element && mapping && pa_alsa_path_set_is_empty(mapping->input_path_set))
+        return;
+
+    u->mixers = pa_hashmap_new_full(pa_idxset_string_hash_func, pa_idxset_string_compare_func,
+                                    NULL, (pa_free_cb_t) pa_alsa_mixer_free);
+
+    mdev = pa_proplist_gets(mapping->proplist, "alsa.mixer_device");
+    if (mdev) {
+        u->mixer_handle = pa_alsa_open_mixer_by_name(u->mixers, mdev, false);
+    } else {
+        u->mixer_handle = pa_alsa_open_mixer_for_pcm(u->mixers, u->pcm_handle, false);
+    }
+    if (!u->mixer_handle) {
+        pa_log_info("Failed to find a working mixer device.");
+        return;
+    }
+
+    if (element) {
+
+        if (!(u->mixer_path = pa_alsa_path_synthesize(element, PA_ALSA_DIRECTION_INPUT)))
+            goto fail;
+
+        if (pa_alsa_path_probe(u->mixer_path, NULL, u->mixer_handle, ignore_dB) < 0)
+            goto fail;
+
+        pa_log_debug("Probed mixer path %s:", u->mixer_path->name);
+        pa_alsa_path_dump(u->mixer_path);
+    } else {
+        u->mixer_path_set = mapping->input_path_set;
+    }
+
+    return;
+
+fail:
+
+    if (u->mixer_path) {
+        pa_alsa_path_free(u->mixer_path);
+        u->mixer_path = NULL;
+    }
+
+    u->mixer_handle = NULL;
+    pa_hashmap_free(u->mixers);
+    u->mixers = NULL;
+}
+
+static int setup_mixer(struct userdata *u, bool ignore_dB) {
+    bool need_mixer_callback = false;
+
+    pa_assert(u);
+
+    /* This code is before the u->mixer_handle check, because if the UCM
+     * configuration doesn't specify volume or mute controls, u->mixer_handle
+     * will be NULL, but the UCM device enable sequence will still need to be
+     * executed. */
+    if (u->source->active_port && u->ucm_context) {
+        if (pa_alsa_ucm_set_port(u->ucm_context, u->source->active_port, false) < 0)
+            return -1;
+    }
+
+    if (!u->mixer_handle)
+        return 0;
+
+    if (u->source->active_port) {
+        if (!u->ucm_context) {
+            pa_alsa_port_data *data;
+
+            /* We have a list of supported paths, so let's activate the
+             * one that has been chosen as active */
+
+            data = PA_DEVICE_PORT_DATA(u->source->active_port);
+            u->mixer_path = data->path;
+
+            pa_alsa_path_select(data->path, data->setting, u->mixer_handle, u->source->muted);
+        } else {
+            pa_alsa_ucm_port_data *data;
+
+            data = PA_DEVICE_PORT_DATA(u->source->active_port);
+
+            /* Now activate volume controls, if any */
+            if (data->path) {
+                u->mixer_path = data->path;
+                pa_alsa_path_select(u->mixer_path, NULL, u->mixer_handle, u->source->muted);
+            }
+        }
+    } else {
+
+        if (!u->mixer_path && u->mixer_path_set)
+            u->mixer_path = pa_hashmap_first(u->mixer_path_set->paths);
+
+        if (u->mixer_path) {
+            /* Hmm, we have only a single path, then let's activate it */
+
+            pa_alsa_path_select(u->mixer_path, u->mixer_path->settings, u->mixer_handle, u->source->muted);
+        } else
+            return 0;
+    }
+
+    mixer_volume_init(u);
+
+    /* Will we need to register callbacks? */
+    if (u->mixer_path_set && u->mixer_path_set->paths) {
+        pa_alsa_path *p;
+        void *state;
+
+        PA_HASHMAP_FOREACH(p, u->mixer_path_set->paths, state) {
+            if (p->has_volume || p->has_mute)
+                need_mixer_callback = true;
+        }
+    }
+    else if (u->mixer_path)
+        need_mixer_callback = u->mixer_path->has_volume || u->mixer_path->has_mute;
+
+    if (need_mixer_callback) {
+        int (*mixer_callback)(snd_mixer_elem_t *, unsigned int);
+        if (u->source->flags & PA_SOURCE_DEFERRED_VOLUME) {
+            u->mixer_pd = pa_alsa_mixer_pdata_new();
+            mixer_callback = io_mixer_callback;
+
+            if (pa_alsa_set_mixer_rtpoll(u->mixer_pd, u->mixer_handle, u->rtpoll) < 0) {
+                pa_log("Failed to initialize file descriptor monitoring");
+                return -1;
+            }
+        } else {
+            u->mixer_fdl = pa_alsa_fdlist_new();
+            mixer_callback = ctl_mixer_callback;
+
+            if (pa_alsa_fdlist_set_handle(u->mixer_fdl, u->mixer_handle, NULL, u->core->mainloop) < 0) {
+                pa_log("Failed to initialize file descriptor monitoring");
+                return -1;
+            }
+        }
+
+        if (u->mixer_path_set)
+            pa_alsa_path_set_set_callback(u->mixer_path_set, u->mixer_handle, mixer_callback, u);
+        else
+            pa_alsa_path_set_callback(u->mixer_path, u->mixer_handle, mixer_callback, u);
+    }
+
+    return 0;
+}
+
+pa_source *pa_alsa_source_new(pa_module *m, pa_modargs *ma, const char*driver, pa_card *card, pa_alsa_mapping *mapping) {
+
+    struct userdata *u = NULL;
+    const char *dev_id = NULL, *key, *mod_name;
+    pa_sample_spec ss;
+    char *thread_name = NULL;
+    uint32_t alternate_sample_rate;
+    pa_channel_map map;
+    uint32_t nfrags, frag_size, buffer_size, tsched_size, tsched_watermark;
+    snd_pcm_uframes_t period_frames, buffer_frames, tsched_frames;
+    size_t frame_size;
+    bool use_mmap = true;
+    bool use_tsched = true;
+    bool ignore_dB = false;
+    bool namereg_fail = false;
+    bool deferred_volume = false;
+    bool fixed_latency_range = false;
+    bool b;
+    bool d;
+    bool avoid_resampling;
+    pa_source_new_data data;
+    bool volume_is_set;
+    bool mute_is_set;
+    pa_alsa_profile_set *profile_set = NULL;
+    void *state;
+
+    pa_assert(m);
+    pa_assert(ma);
+
+    ss = m->core->default_sample_spec;
+    map = m->core->default_channel_map;
+    avoid_resampling = m->core->avoid_resampling;
+
+    /* Pick sample spec overrides from the mapping, if any */
+    if (mapping) {
+        if (mapping->sample_spec.format != PA_SAMPLE_INVALID)
+            ss.format = mapping->sample_spec.format;
+        if (mapping->sample_spec.rate != 0)
+            ss.rate = mapping->sample_spec.rate;
+        if (mapping->sample_spec.channels != 0) {
+            ss.channels = mapping->sample_spec.channels;
+            if (pa_channel_map_valid(&mapping->channel_map))
+                pa_assert(pa_channel_map_compatible(&mapping->channel_map, &ss));
+        }
+    }
+
+    /* Override with modargs if provided */
+    if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_ALSA) < 0) {
+        pa_log("Failed to parse sample specification and channel map");
+        goto fail;
+    }
+
+    alternate_sample_rate = m->core->alternate_sample_rate;
+    if (pa_modargs_get_alternate_sample_rate(ma, &alternate_sample_rate) < 0) {
+        pa_log("Failed to parse alternate sample rate");
+        goto fail;
+    }
+
+    frame_size = pa_frame_size(&ss);
+
+    nfrags = m->core->default_n_fragments;
+    frag_size = (uint32_t) pa_usec_to_bytes(m->core->default_fragment_size_msec*PA_USEC_PER_MSEC, &ss);
+    if (frag_size <= 0)
+        frag_size = (uint32_t) frame_size;
+    tsched_size = (uint32_t) pa_usec_to_bytes(DEFAULT_TSCHED_BUFFER_USEC, &ss);
+    tsched_watermark = (uint32_t) pa_usec_to_bytes(DEFAULT_TSCHED_WATERMARK_USEC, &ss);
+
+    if (pa_modargs_get_value_u32(ma, "fragments", &nfrags) < 0 ||
+        pa_modargs_get_value_u32(ma, "fragment_size", &frag_size) < 0 ||
+        pa_modargs_get_value_u32(ma, "tsched_buffer_size", &tsched_size) < 0 ||
+        pa_modargs_get_value_u32(ma, "tsched_buffer_watermark", &tsched_watermark) < 0) {
+        pa_log("Failed to parse buffer metrics");
+        goto fail;
+    }
+
+    buffer_size = nfrags * frag_size;
+
+    period_frames = frag_size/frame_size;
+    buffer_frames = buffer_size/frame_size;
+    tsched_frames = tsched_size/frame_size;
+
+    if (pa_modargs_get_value_boolean(ma, "mmap", &use_mmap) < 0) {
+        pa_log("Failed to parse mmap argument.");
+        goto fail;
+    }
+
+    if (pa_modargs_get_value_boolean(ma, "tsched", &use_tsched) < 0) {
+        pa_log("Failed to parse tsched argument.");
+        goto fail;
+    }
+
+    if (pa_modargs_get_value_boolean(ma, "ignore_dB", &ignore_dB) < 0) {
+        pa_log("Failed to parse ignore_dB argument.");
+        goto fail;
+    }
+
+    deferred_volume = m->core->deferred_volume;
+    if (pa_modargs_get_value_boolean(ma, "deferred_volume", &deferred_volume) < 0) {
+        pa_log("Failed to parse deferred_volume argument.");
+        goto fail;
+    }
+
+    if (pa_modargs_get_value_boolean(ma, "fixed_latency_range", &fixed_latency_range) < 0) {
+        pa_log("Failed to parse fixed_latency_range argument.");
+        goto fail;
+    }
+
+    use_tsched = pa_alsa_may_tsched(use_tsched);
+
+    u = pa_xnew0(struct userdata, 1);
+    u->core = m->core;
+    u->module = m;
+    u->use_mmap = use_mmap;
+    u->use_tsched = use_tsched;
+    u->tsched_size = tsched_size;
+    u->initial_info.nfrags = (size_t) nfrags;
+    u->initial_info.fragment_size = (size_t) frag_size;
+    u->initial_info.tsched_size = (size_t) tsched_size;
+    u->initial_info.tsched_watermark = (size_t) tsched_watermark;
+    u->deferred_volume = deferred_volume;
+    u->fixed_latency_range = fixed_latency_range;
+    u->first = true;
+    u->rtpoll = pa_rtpoll_new();
+
+    if (pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll) < 0) {
+        pa_log("pa_thread_mq_init() failed.");
+        goto fail;
+    }
+
+    u->smoother = pa_smoother_new(
+            SMOOTHER_ADJUST_USEC,
+            SMOOTHER_WINDOW_USEC,
+            true,
+            true,
+            5,
+            pa_rtclock_now(),
+            true);
+    u->smoother_interval = SMOOTHER_MIN_INTERVAL;
+
+    /* use ucm */
+    if (mapping && mapping->ucm_context.ucm)
+        u->ucm_context = &mapping->ucm_context;
+
+    dev_id = pa_modargs_get_value(
+            ma, "device_id",
+            pa_modargs_get_value(ma, "device", DEFAULT_DEVICE));
+
+    u->paths_dir = pa_xstrdup(pa_modargs_get_value(ma, "paths_dir", NULL));
+
+    if (reserve_init(u, dev_id) < 0)
+        goto fail;
+
+    if (reserve_monitor_init(u, dev_id) < 0)
+        goto fail;
+
+    b = use_mmap;
+    d = use_tsched;
+
+    /* Force ALSA to reread its configuration if module-alsa-card didn't
+     * do it for us. This matters if our device was hot-plugged after ALSA
+     * has already read its configuration - see
+     * https://bugs.freedesktop.org/show_bug.cgi?id=54029
+     */
+
+    if (!card)
+        snd_config_update_free_global();
+
+    if (mapping) {
+
+        if (!(dev_id = pa_modargs_get_value(ma, "device_id", NULL))) {
+            pa_log("device_id= not set");
+            goto fail;
+        }
+
+        if ((mod_name = pa_proplist_gets(mapping->proplist, PA_ALSA_PROP_UCM_MODIFIER))) {
+            if (snd_use_case_set(u->ucm_context->ucm->ucm_mgr, "_enamod", mod_name) < 0)
+                pa_log("Failed to enable ucm modifier %s", mod_name);
+            else
+                pa_log_debug("Enabled ucm modifier %s", mod_name);
+        }
+
+        if (!(u->pcm_handle = pa_alsa_open_by_device_id_mapping(
+                      dev_id,
+                      &u->device_name,
+                      &ss, &map,
+                      SND_PCM_STREAM_CAPTURE,
+                      &period_frames, &buffer_frames, tsched_frames,
+                      &b, &d, mapping)))
+            goto fail;
+
+    } else if ((dev_id = pa_modargs_get_value(ma, "device_id", NULL))) {
+
+        if (!(profile_set = pa_alsa_profile_set_new(NULL, &map)))
+            goto fail;
+
+        if (!(u->pcm_handle = pa_alsa_open_by_device_id_auto(
+                      dev_id,
+                      &u->device_name,
+                      &ss, &map,
+                      SND_PCM_STREAM_CAPTURE,
+                      &period_frames, &buffer_frames, tsched_frames,
+                      &b, &d, profile_set, &mapping)))
+            goto fail;
+
+    } else {
+
+        if (!(u->pcm_handle = pa_alsa_open_by_device_string(
+                      pa_modargs_get_value(ma, "device", DEFAULT_DEVICE),
+                      &u->device_name,
+                      &ss, &map,
+                      SND_PCM_STREAM_CAPTURE,
+                      &period_frames, &buffer_frames, tsched_frames,
+                      &b, &d, false)))
+            goto fail;
+    }
+
+    pa_assert(u->device_name);
+    pa_log_info("Successfully opened device %s.", u->device_name);
+
+    if (pa_alsa_pcm_is_modem(u->pcm_handle)) {
+        pa_log_notice("Device %s is modem, refusing further initialization.", u->device_name);
+        goto fail;
+    }
+
+    if (mapping)
+        pa_log_info("Selected mapping '%s' (%s).", mapping->description, mapping->name);
+
+    if (use_mmap && !b) {
+        pa_log_info("Device doesn't support mmap(), falling back to UNIX read/write mode.");
+        u->use_mmap = use_mmap = false;
+    }
+
+    if (use_tsched && (!b || !d)) {
+        pa_log_info("Cannot enable timer-based scheduling, falling back to sound IRQ scheduling.");
+        u->use_tsched = use_tsched = false;
+    }
+
+    if (u->use_mmap)
+        pa_log_info("Successfully enabled mmap() mode.");
+
+    if (u->use_tsched) {
+        pa_log_info("Successfully enabled timer-based scheduling mode.");
+        if (u->fixed_latency_range)
+            pa_log_info("Disabling latency range changes on overrun");
+    }
+
+    u->verified_sample_spec = ss;
+
+    u->supported_formats = pa_alsa_get_supported_formats(u->pcm_handle, ss.format);
+    if (!u->supported_formats) {
+        pa_log_error("Failed to find any supported sample formats.");
+        goto fail;
+    }
+
+    u->supported_rates = pa_alsa_get_supported_rates(u->pcm_handle, ss.rate);
+    if (!u->supported_rates) {
+        pa_log_error("Failed to find any supported sample rates.");
+        goto fail;
+    }
+
+    /* ALSA might tweak the sample spec, so recalculate the frame size */
+    frame_size = pa_frame_size(&ss);
+
+    pa_source_new_data_init(&data);
+    data.driver = driver;
+    data.module = m;
+    data.card = card;
+    set_source_name(&data, ma, dev_id, u->device_name, mapping);
+
+    /* We need to give pa_modargs_get_value_boolean() a pointer to a local
+     * variable instead of using &data.namereg_fail directly, because
+     * data.namereg_fail is a bitfield and taking the address of a bitfield
+     * variable is impossible. */
+    namereg_fail = data.namereg_fail;
+    if (pa_modargs_get_value_boolean(ma, "namereg_fail", &namereg_fail) < 0) {
+        pa_log("Failed to parse namereg_fail argument.");
+        pa_source_new_data_done(&data);
+        goto fail;
+    }
+    data.namereg_fail = namereg_fail;
+
+    if (pa_modargs_get_value_boolean(ma, "avoid_resampling", &avoid_resampling) < 0) {
+        pa_log("Failed to parse avoid_resampling argument.");
+        pa_source_new_data_done(&data);
+        goto fail;
+    }
+    pa_source_new_data_set_avoid_resampling(&data, avoid_resampling);
+
+    pa_source_new_data_set_sample_spec(&data, &ss);
+    pa_source_new_data_set_channel_map(&data, &map);
+    pa_source_new_data_set_alternate_sample_rate(&data, alternate_sample_rate);
+
+    pa_alsa_init_proplist_pcm(m->core, data.proplist, u->pcm_handle);
+    pa_proplist_sets(data.proplist, PA_PROP_DEVICE_STRING, u->device_name);
+    pa_proplist_setf(data.proplist, PA_PROP_DEVICE_BUFFERING_BUFFER_SIZE, "%lu", (unsigned long) (buffer_frames * frame_size));
+    pa_proplist_setf(data.proplist, PA_PROP_DEVICE_BUFFERING_FRAGMENT_SIZE, "%lu", (unsigned long) (period_frames * frame_size));
+    pa_proplist_sets(data.proplist, PA_PROP_DEVICE_ACCESS_MODE, u->use_tsched ? "mmap+timer" : (u->use_mmap ? "mmap" : "serial"));
+
+    if (mapping) {
+        pa_proplist_sets(data.proplist, PA_PROP_DEVICE_PROFILE_NAME, mapping->name);
+        pa_proplist_sets(data.proplist, PA_PROP_DEVICE_PROFILE_DESCRIPTION, mapping->description);
+
+        state = NULL;
+        while ((key = pa_proplist_iterate(mapping->proplist, &state)))
+            pa_proplist_sets(data.proplist, key, pa_proplist_gets(mapping->proplist, key));
+    }
+
+    pa_alsa_init_description(data.proplist, card);
+
+    if (u->control_device)
+        pa_alsa_init_proplist_ctl(data.proplist, u->control_device);
+
+    if (pa_modargs_get_proplist(ma, "source_properties", data.proplist, PA_UPDATE_REPLACE) < 0) {
+        pa_log("Invalid properties");
+        pa_source_new_data_done(&data);
+        goto fail;
+    }
+
+    if (u->ucm_context) {
+        pa_alsa_ucm_add_ports(&data.ports, data.proplist, u->ucm_context, false, card, u->pcm_handle, ignore_dB);
+        find_mixer(u, mapping, pa_modargs_get_value(ma, "control", NULL), ignore_dB);
+    } else {
+        find_mixer(u, mapping, pa_modargs_get_value(ma, "control", NULL), ignore_dB);
+        if (u->mixer_path_set)
+            pa_alsa_add_ports(&data, u->mixer_path_set, card);
+    }
+
+    u->source = pa_source_new(m->core, &data, PA_SOURCE_HARDWARE|PA_SOURCE_LATENCY|(u->use_tsched ? PA_SOURCE_DYNAMIC_LATENCY : 0));
+    volume_is_set = data.volume_is_set;
+    mute_is_set = data.muted_is_set;
+    pa_source_new_data_done(&data);
+
+    if (!u->source) {
+        pa_log("Failed to create source object");
+        goto fail;
+    }
+
+    if (u->ucm_context) {
+        pa_device_port *port;
+        unsigned h_prio = 0;
+        PA_HASHMAP_FOREACH(port, u->source->ports, state) {
+            if (!h_prio || port->priority > h_prio)
+                h_prio = port->priority;
+        }
+        /* ucm ports prioriy is 100, 200, ..., 900, change it to units digit */
+        h_prio = h_prio / 100;
+        u->source->priority += h_prio;
+    }
+
+    if (pa_modargs_get_value_u32(ma, "deferred_volume_safety_margin",
+                                 &u->source->thread_info.volume_change_safety_margin) < 0) {
+        pa_log("Failed to parse deferred_volume_safety_margin parameter");
+        goto fail;
+    }
+
+    if (pa_modargs_get_value_s32(ma, "deferred_volume_extra_delay",
+                                 &u->source->thread_info.volume_change_extra_delay) < 0) {
+        pa_log("Failed to parse deferred_volume_extra_delay parameter");
+        goto fail;
+    }
+
+    u->source->parent.process_msg = source_process_msg;
+    if (u->use_tsched)
+        u->source->update_requested_latency = source_update_requested_latency_cb;
+    u->source->set_state_in_main_thread = source_set_state_in_main_thread_cb;
+    u->source->set_state_in_io_thread = source_set_state_in_io_thread_cb;
+    if (u->ucm_context)
+        u->source->set_port = source_set_port_ucm_cb;
+    else
+        u->source->set_port = source_set_port_cb;
+    u->source->reconfigure = source_reconfigure_cb;
+    u->source->userdata = u;
+
+    pa_source_set_asyncmsgq(u->source, u->thread_mq.inq);
+    pa_source_set_rtpoll(u->source, u->rtpoll);
+
+    u->frame_size = frame_size;
+    u->frames_per_block = pa_mempool_block_size_max(m->core->mempool) / frame_size;
+    u->fragment_size = frag_size = (size_t) (period_frames * frame_size);
+    u->hwbuf_size = buffer_size = (size_t) (buffer_frames * frame_size);
+    pa_cvolume_mute(&u->hardware_volume, u->source->sample_spec.channels);
+
+    pa_log_info("Using %0.1f fragments of size %lu bytes (%0.2fms), buffer size is %lu bytes (%0.2fms)",
+                (double) u->hwbuf_size / (double) u->fragment_size,
+                (long unsigned) u->fragment_size,
+                (double) pa_bytes_to_usec(u->fragment_size, &ss) / PA_USEC_PER_MSEC,
+                (long unsigned) u->hwbuf_size,
+                (double) pa_bytes_to_usec(u->hwbuf_size, &ss) / PA_USEC_PER_MSEC);
+
+    if (u->use_tsched) {
+        u->tsched_watermark_ref = tsched_watermark;
+        reset_watermark(u, u->tsched_watermark_ref, &ss, false);
+    }
+    else
+        pa_source_set_fixed_latency(u->source, pa_bytes_to_usec(u->hwbuf_size, &ss));
+
+    reserve_update(u);
+
+    if (update_sw_params(u) < 0)
+        goto fail;
+
+    if (setup_mixer(u, ignore_dB) < 0)
+        goto fail;
+
+    pa_alsa_dump(PA_LOG_DEBUG, u->pcm_handle);
+
+    thread_name = pa_sprintf_malloc("alsa-source-%s", pa_strnull(pa_proplist_gets(u->source->proplist, "alsa.id")));
+    if (!(u->thread = pa_thread_new(thread_name, thread_func, u))) {
+        pa_log("Failed to create thread.");
+        goto fail;
+    }
+    pa_xfree(thread_name);
+    thread_name = NULL;
+
+    /* Get initial mixer settings */
+    if (volume_is_set) {
+        if (u->source->set_volume)
+            u->source->set_volume(u->source);
+    } else {
+        if (u->source->get_volume)
+            u->source->get_volume(u->source);
+    }
+
+    if (mute_is_set) {
+        if (u->source->set_mute)
+            u->source->set_mute(u->source);
+    } else {
+        if (u->source->get_mute) {
+            bool mute;
+
+            if (u->source->get_mute(u->source, &mute) >= 0)
+                pa_source_set_mute(u->source, mute, false);
+        }
+    }
+
+    if ((volume_is_set || mute_is_set) && u->source->write_volume)
+        u->source->write_volume(u->source);
+
+    pa_source_put(u->source);
+
+    if (profile_set)
+        pa_alsa_profile_set_free(profile_set);
+
+    return u->source;
+
+fail:
+    pa_xfree(thread_name);
+
+    if (u)
+        userdata_free(u);
+
+    if (profile_set)
+        pa_alsa_profile_set_free(profile_set);
+
+    return NULL;
+}
+
+static void userdata_free(struct userdata *u) {
+    pa_assert(u);
+
+    if (u->source)
+        pa_source_unlink(u->source);
+
+    if (u->thread) {
+        pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
+        pa_thread_free(u->thread);
+    }
+
+    pa_thread_mq_done(&u->thread_mq);
+
+    if (u->source)
+        pa_source_unref(u->source);
+
+    if (u->mixer_pd)
+        pa_alsa_mixer_pdata_free(u->mixer_pd);
+
+    if (u->alsa_rtpoll_item)
+        pa_rtpoll_item_free(u->alsa_rtpoll_item);
+
+    if (u->rtpoll)
+        pa_rtpoll_free(u->rtpoll);
+
+    if (u->pcm_handle) {
+        snd_pcm_drop(u->pcm_handle);
+        snd_pcm_close(u->pcm_handle);
+    }
+
+    if (u->mixer_fdl)
+        pa_alsa_fdlist_free(u->mixer_fdl);
+
+    /* Only free the mixer_path if the sink owns it */
+    if (u->mixer_path && !u->mixer_path_set && !u->ucm_context)
+        pa_alsa_path_free(u->mixer_path);
+
+    if (u->mixers)
+        pa_hashmap_free(u->mixers);
+
+    if (u->smoother)
+        pa_smoother_free(u->smoother);
+
+    if (u->supported_formats)
+        pa_xfree(u->supported_formats);
+
+    if (u->supported_rates)
+        pa_xfree(u->supported_rates);
+
+    reserve_done(u);
+    monitor_done(u);
+
+    pa_xfree(u->device_name);
+    pa_xfree(u->control_device);
+    pa_xfree(u->paths_dir);
+    pa_xfree(u);
+}
+
+void pa_alsa_source_free(pa_source *s) {
+    struct userdata *u;
+
+    pa_source_assert_ref(s);
+    pa_assert_se(u = s->userdata);
+
+    userdata_free(u);
+}