]> code.delx.au - pulseaudio/blobdiff - src/modules/module-alsa-source.c
Merge branch 'master' of ssh://rootserver/home/lennart/git/public/pulseaudio
[pulseaudio] / src / modules / module-alsa-source.c
index 9922668bfac05425c38207fa63b75a9438619b7a..a6e4c9074cd3f03e3de2520b482423966f7c17da 100644 (file)
@@ -1,9 +1,7 @@
-/* $Id$ */
-
 /***
   This file is part of PulseAudio.
 
-  Copyright 2004-2006 Lennart Poettering
+  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
 #include <config.h>
 #endif
 
-#include <assert.h>
 #include <stdio.h>
 
 #include <asoundlib.h>
 
+#ifdef HAVE_VALGRIND_MEMCHECK_H
+#include <valgrind/memcheck.h>
+#endif
+
 #include <pulse/xmalloc.h>
 #include <pulse/util.h>
+#include <pulse/timeval.h>
 
 #include <pulsecore/core-error.h>
 #include <pulsecore/core.h>
 #include <pulsecore/core-error.h>
 #include <pulsecore/thread-mq.h>
 #include <pulsecore/rtpoll.h>
+#include <pulsecore/time-smoother.h>
+#include <pulsecore/rtclock.h>
 
 #include "alsa-util.h"
 #include "module-alsa-source-symdef.h"
 
-PA_MODULE_AUTHOR("Lennart Poettering")
-PA_MODULE_DESCRIPTION("ALSA Source")
-PA_MODULE_VERSION(PACKAGE_VERSION)
+PA_MODULE_AUTHOR("Lennart Poettering");
+PA_MODULE_DESCRIPTION("ALSA Source");
+PA_MODULE_VERSION(PACKAGE_VERSION);
+PA_MODULE_LOAD_ONCE(FALSE);
 PA_MODULE_USAGE(
         "source_name=<name for the source> "
         "device=<ALSA device> "
+        "device_id=<ALSA card index> "
         "format=<sample format> "
-        "channels=<number of channels> "
         "rate=<sample rate> "
+        "channels=<number of channels> "
+        "channel_map=<channel map> "
         "fragments=<number of fragments> "
         "fragment_size=<fragment size> "
-        "channel_map=<channel map> "
-        "mmap=<enable memory mapping?>")
+        "mmap=<enable memory mapping?> "
+        "tsched=<enable system timer based scheduling mode?> "
+        "tsched_buffer_size=<buffer size when using timer based scheduling> "
+        "tsched_buffer_watermark=<upper fill watermark>");
+
+static const char* const valid_modargs[] = {
+    "source_name",
+    "device",
+    "device_id",
+    "format",
+    "rate",
+    "channels",
+    "channel_map",
+    "fragments",
+    "fragment_size",
+    "mmap",
+    "tsched",
+    "tsched_buffer_size",
+    "tsched_buffer_watermark",
+    NULL
+};
 
 #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_MIN_SLEEP_USEC (3*PA_USEC_PER_MSEC)           /* 3ms */
+#define TSCHED_MIN_WAKEUP_USEC (3*PA_USEC_PER_MSEC)          /* 3ms */
 
 struct userdata {
     pa_core *core;
     pa_module *module;
     pa_source *source;
-    
+
     pa_thread *thread;
     pa_thread_mq thread_mq;
     pa_rtpoll *rtpoll;
@@ -83,235 +113,388 @@ struct userdata {
     snd_mixer_t *mixer_handle;
     snd_mixer_elem_t *mixer_elem;
     long hw_volume_max, hw_volume_min;
+    long hw_dB_max, hw_dB_min;
+    pa_bool_t hw_dB_supported;
+    pa_bool_t mixer_seperate_channels;
+
+    pa_cvolume hardware_volume;
 
-    size_t frame_size, fragment_size, hwbuf_size;
+    size_t frame_size, fragment_size, hwbuf_size, tsched_watermark;
     unsigned nfragments;
 
     char *device_name;
 
-    int use_mmap;
+    pa_bool_t use_mmap, use_tsched;
 
     pa_rtpoll_item *alsa_rtpoll_item;
-};
 
-static const char* const valid_modargs[] = {
-    "device",
-    "source_name",
-    "channels",
-    "rate",
-    "format",
-    "fragments",
-    "fragment_size",
-    "channel_map",
-    "mmap",
-    NULL
+    snd_mixer_selem_channel_id_t mixer_map[SND_MIXER_SCHN_LAST];
+
+    pa_smoother *smoother;
+    int64_t frame_index;
+
+    snd_pcm_sframes_t hwbuf_unused_frames;
 };
 
-static int mmap_read(struct userdata *u) {
+static void fix_tsched_watermark(struct userdata *u) {
+    size_t max_use;
+    size_t min_sleep, min_wakeup;
+    pa_assert(u);
+
+    max_use = u->hwbuf_size - (size_t) u->hwbuf_unused_frames * u->frame_size;
+
+    min_sleep = pa_usec_to_bytes(TSCHED_MIN_SLEEP_USEC, &u->source->sample_spec);
+    min_wakeup = pa_usec_to_bytes(TSCHED_MIN_WAKEUP_USEC, &u->source->sample_spec);
+
+    if (min_sleep > max_use/2)
+        min_sleep = pa_frame_align(max_use/2, &u->source->sample_spec);
+    if (min_sleep < u->frame_size)
+        min_sleep = u->frame_size;
+
+    if (min_wakeup > max_use/2)
+        min_wakeup = pa_frame_align(max_use/2, &u->source->sample_spec);
+    if (min_wakeup < u->frame_size)
+        min_wakeup = u->frame_size;
+
+    if (u->tsched_watermark > max_use-min_sleep)
+        u->tsched_watermark = max_use-min_sleep;
+
+    if (u->tsched_watermark < min_wakeup)
+        u->tsched_watermark = min_wakeup;
+}
+
+static pa_usec_t hw_sleep_time(struct userdata *u, pa_usec_t *sleep_usec, pa_usec_t*process_usec) {
+    pa_usec_t wm, usec;
+
+    pa_assert(u);
+
+    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);
+
+/*     pa_log_debug("hw buffer time: %u ms", (unsigned) (usec / PA_USEC_PER_MSEC)); */
+
+    wm = pa_bytes_to_usec(u->tsched_watermark, &u->source->sample_spec);
+
+    if (usec >= wm) {
+        *sleep_usec = usec - wm;
+        *process_usec = wm;
+    } else
+        *process_usec = *sleep_usec = usec /= 2;
+
+/*     pa_log_debug("after watermark: %u ms", (unsigned) (*sleep_usec / PA_USEC_PER_MSEC)); */
+
+    return usec;
+}
+
+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, snd_strerror(err));
+
+    pa_assert(err != -EAGAIN);
+
+    if (err == -EPIPE)
+        pa_log_debug("%s: Buffer overrun!", call);
+
+    if ((err = snd_pcm_recover(u->pcm_handle, err, 1)) == 0) {
+        snd_pcm_start(u->pcm_handle);
+        return 0;
+    }
+
+    pa_log("%s: %s", call, snd_strerror(err));
+    return -1;
+}
+
+static size_t check_left_to_record(struct userdata *u, snd_pcm_sframes_t n) {
+    size_t left_to_record;
+    size_t rec_space = u->hwbuf_size - (size_t) u->hwbuf_unused_frames*u->frame_size;
+
+    if ((size_t) n*u->frame_size < rec_space)
+        left_to_record = rec_space - ((size_t) n*u->frame_size);
+    else
+        left_to_record = 0;
+
+    if (left_to_record > 0) {
+/*         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); */
+    } else {
+        pa_log_info("Overrun!");
+
+        if (u->use_tsched) {
+            size_t old_watermark = u->tsched_watermark;
+
+            u->tsched_watermark *= 2;
+            fix_tsched_watermark(u);
+
+            if (old_watermark != u->tsched_watermark)
+                pa_log_notice("Increasing wakeup watermark to %0.2f ms",
+                              (double) pa_bytes_to_usec(u->tsched_watermark, &u->source->sample_spec) / PA_USEC_PER_MSEC);
+        }
+    }
+
+    return left_to_record;
+}
+
+static int mmap_read(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polled) {
     int work_done = 0;
-    
+    pa_usec_t max_sleep_usec = 0, process_usec = 0;
+    size_t left_to_record;
+
     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;
-        int err;
-        const snd_pcm_channel_area_t *areas;
-        snd_pcm_uframes_t offset, frames;
-        pa_memchunk chunk;
-        void *p;
-        
-        if ((n = snd_pcm_avail_update(u->pcm_handle)) < 0) {
-
-            if (n == -EPIPE)
-                pa_log_debug("snd_pcm_avail_update: Buffer underrun!");
-            
-            if ((err = snd_pcm_recover(u->pcm_handle, n, 1)) == 0)
+        int r;
+
+        snd_pcm_hwsync(u->pcm_handle);
+
+        if (PA_UNLIKELY((n = pa_alsa_safe_avail_update(u->pcm_handle, u->hwbuf_size, &u->source->sample_spec)) < 0)) {
+
+            if ((r = try_recover(u, "snd_pcm_avail_update", (int) n)) == 0)
                 continue;
 
-            if (err == -EAGAIN)
-                return work_done;
-            
-            pa_log("snd_pcm_avail_update: %s", snd_strerror(err));
-            return -1;
+            return r;
         }
 
-/*         pa_log("Got request for %i samples", (int) n); */
-        
-        if (n <= 0)
-            return work_done;
+        left_to_record = check_left_to_record(u, n);
 
-        frames = n;
-        
-        if ((err = snd_pcm_mmap_begin(u->pcm_handle, &areas, &offset, &frames)) < 0) {
-            
-            if (err == -EPIPE)
-                pa_log_debug("snd_pcm_mmap_begin: Buffer underrun!");
+        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 ((err = snd_pcm_recover(u->pcm_handle, err, 1)) == 0)
-                continue;
+        if (PA_UNLIKELY(n <= 0)) {
 
-            if (err == -EAGAIN)
-                return work_done;
+            if (polled)
+                pa_log("ALSA woke us up to read new data from the device, but there was actually nothing to read! "
+                       "Most likely this is an ALSA driver bug. Please report this issue to the PulseAudio device.");
 
-            pa_log("Failed to write data to DSP: %s", snd_strerror(err));
-            return -1;
+            break;
         }
 
-        /* Check these are multiples of 8 bit */
-        pa_assert((areas[0].first & 7) == 0);
-        pa_assert((areas[0].step & 7)== 0);
+        polled = FALSE;
 
-        /* We assume a single interleaved memory buffer */
-        pa_assert((areas[0].first >> 3) == 0);
-        pa_assert((areas[0].step >> 3) == u->frame_size);
+        for (;;) {
+            int err;
+            const snd_pcm_channel_area_t *areas;
+            snd_pcm_uframes_t offset, frames = (snd_pcm_uframes_t) n;
+            pa_memchunk chunk;
+            void *p;
+            snd_pcm_sframes_t sframes;
 
-        p = (uint8_t*) areas[0].addr + (offset * u->frame_size);
-        
-        chunk.memblock = pa_memblock_new_fixed(u->core->mempool, p, frames * u->frame_size, 1);
-        chunk.length = pa_memblock_get_length(chunk.memblock);
-        chunk.index = 0;
+/*             pa_log_debug("%lu frames to read", (unsigned long) frames); */
 
-        pa_source_post(u->source, &chunk);
+            if (PA_UNLIKELY((err = pa_alsa_safe_mmap_begin(u->pcm_handle, &areas, &offset, &frames, u->hwbuf_size, &u->source->sample_spec)) < 0)) {
 
-        /* FIXME: Maybe we can do something to keep this memory block
-         * a little bit longer around? */
-        pa_memblock_unref_fixed(chunk.memblock);
+                if ((r = try_recover(u, "snd_pcm_mmap_begin", err)) == 0)
+                    continue;
 
-        if ((err = snd_pcm_mmap_commit(u->pcm_handle, offset, frames)) < 0) {
+                return r;
+            }
 
-            if (err == -EPIPE)
-                pa_log_debug("snd_pcm_mmap_commit: Buffer underrun!");
-            
-            if ((err = snd_pcm_recover(u->pcm_handle, err, 1)) == 0)
-                continue;
-            
-            if (err == -EAGAIN)
-                return work_done;
-            
-            pa_log("Failed to write data to DSP: %s", snd_strerror(err));
-            return -1;
-        }
+            /* Make sure that if these memblocks need to be copied they will fit into one slot */
+            if (frames > pa_mempool_block_size_max(u->source->core->mempool)/u->frame_size)
+                frames = pa_mempool_block_size_max(u->source->core->mempool)/u->frame_size;
+
+            /* 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)) {
+
+                if ((r = try_recover(u, "snd_pcm_mmap_commit", (int) sframes)) == 0)
+                    continue;
+
+                return r;
+            }
+
+            work_done = 1;
+
+            u->frame_index += (int64_t) frames;
+
+/*             pa_log_debug("read %lu frames", (unsigned long) frames); */
 
-        work_done = 1;
+            if (frames >= (snd_pcm_uframes_t) n)
+                break;
 
-/*         pa_log("wrote %i samples", (int) frames); */
+            n -= (snd_pcm_sframes_t) frames;
+        }
     }
+
+    *sleep_usec = pa_bytes_to_usec(left_to_record, &u->source->sample_spec) - process_usec;
+    return work_done;
 }
 
-static int unix_read(struct userdata *u) {
-    snd_pcm_status_t *status;
+static int unix_read(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polled) {
     int work_done = 0;
-
-    snd_pcm_status_alloca(&status);
+    pa_usec_t max_sleep_usec = 0, process_usec = 0;
+    size_t left_to_record;
 
     pa_assert(u);
     pa_source_assert_ref(u->source);
 
+    if (u->use_tsched)
+        hw_sleep_time(u, &max_sleep_usec, &process_usec);
+
     for (;;) {
-        void *p;
-        snd_pcm_sframes_t t;
-        ssize_t l;
-        int err;
-        pa_memchunk chunk;
-        
-        if ((err = snd_pcm_status(u->pcm_handle, status)) < 0) {
-            pa_log("Failed to query DSP status data: %s", snd_strerror(err));
-            return -1;
+        snd_pcm_sframes_t n;
+        int r;
+
+        snd_pcm_hwsync(u->pcm_handle);
+
+        if (PA_UNLIKELY((n = pa_alsa_safe_avail_update(u->pcm_handle, u->hwbuf_size, &u->source->sample_spec)) < 0)) {
+
+            if ((r = try_recover(u, "snd_pcm_avail_update", (int) n)) == 0)
+                continue;
+
+            return r;
         }
 
-        if (snd_pcm_status_get_avail_max(status)*u->frame_size >= u->hwbuf_size)
-            pa_log_debug("Buffer overrun!");
-                    
-        l = snd_pcm_status_get_avail(status) * u->frame_size;
+        left_to_record = check_left_to_record(u, n);
+
+        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 <= 0)) {
+
+            if (polled)
+                pa_log("ALSA woke us up to read new data from the device, but there was actually nothing to read! "
+                       "Most likely this is an ALSA driver bug. Please report this issue to the PulseAudio developers.");
 
-        if (l <= 0)
             return work_done;
-                    
-        chunk.memblock = pa_memblock_new(u->core->mempool, l);
-
-        p = pa_memblock_acquire(chunk.memblock);
-        t = snd_pcm_readi(u->pcm_handle, (uint8_t*) p, l / u->frame_size);
-        pa_memblock_release(chunk.memblock);
-        
-/*                     pa_log("wrote %i bytes of %u (%u)", t*u->frame_size, u->memchunk.length, l);   */
-        
-        pa_assert(t != 0);
-                    
-        if (t < 0) {
-            pa_memblock_unref(chunk.memblock);
-            
-            if ((t = snd_pcm_recover(u->pcm_handle, t, 1)) == 0)
-                continue;
-                        
-            if (t == -EAGAIN) {
-                pa_log_debug("EAGAIN");
-                return work_done;
-            } else {
-                pa_log("Failed to read data from DSP: %s", snd_strerror(t));
-                return -1;
+        }
+
+        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 > n)
+                frames = n;
+
+/*             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);
+
+            pa_assert(frames != 0);
+
+            if (PA_UNLIKELY(frames < 0)) {
+                pa_memblock_unref(chunk.memblock);
+
+                if ((r = try_recover(u, "snd_pcm_readi", (int) (frames))) == 0)
+                    continue;
+
+                return r;
             }
-        } 
-                        
-        chunk.index = 0;
-        chunk.length = t * u->frame_size;
 
-        pa_source_post(u->source, &chunk);
-        pa_memblock_unref(chunk.memblock);
-                    
-        work_done = 1;
+            chunk.index = 0;
+            chunk.length = (size_t) frames * u->frame_size;
 
-        if (t * u->frame_size >= (unsigned) l)
-            return work_done;
+            pa_source_post(u->source, &chunk);
+            pa_memblock_unref(chunk.memblock);
+
+            work_done = 1;
+
+            u->frame_index += frames;
+
+/*             pa_log_debug("read %lu frames", (unsigned long) frames); */
+
+            if (frames >= n)
+                break;
+
+            n -= frames;
+        }
     }
+
+    *sleep_usec = pa_bytes_to_usec(left_to_record, &u->source->sample_spec) - process_usec;
+    return work_done;
 }
 
-static pa_usec_t source_get_latency(struct userdata *u) {
-    pa_usec_t r = 0;
-    snd_pcm_status_t *status;
-    snd_pcm_sframes_t frames = 0;
+static void update_smoother(struct userdata *u) {
+    snd_pcm_sframes_t delay = 0;
+    int64_t frames;
     int err;
+    pa_usec_t now1, now2;
 
-    snd_pcm_status_alloca(&status);
-    
     pa_assert(u);
     pa_assert(u->pcm_handle);
 
-    if ((err = snd_pcm_status(u->pcm_handle, status)) < 0) 
-        pa_log("Failed to get delay: %s", snd_strerror(err));
-    else
-        frames = snd_pcm_status_get_delay(status);
+    /* Let's update the time smoother */
+
+    snd_pcm_hwsync(u->pcm_handle);
+    snd_pcm_avail_update(u->pcm_handle);
+
+    if (PA_UNLIKELY((err = snd_pcm_delay(u->pcm_handle, &delay)) < 0)) {
+        pa_log_warn("Failed to get delay: %s", snd_strerror(err));
+        return;
+    }
+
+    frames = u->frame_index + delay;
+
+    now1 = pa_rtclock_usec();
+    now2 = pa_bytes_to_usec((uint64_t) frames * u->frame_size, &u->source->sample_spec);
 
-    if (frames > 0)
-        r = pa_bytes_to_usec(frames * u->frame_size, &u->source->sample_spec);
+    pa_smoother_put(u->smoother, now1, now2);
+}
+
+static pa_usec_t source_get_latency(struct userdata *u) {
+    pa_usec_t r = 0;
+    int64_t delay;
+    pa_usec_t now1, now2;
+
+    pa_assert(u);
+
+    now1 = pa_rtclock_usec();
+    now2 = pa_smoother_get(u->smoother, now1);
+
+    delay = (int64_t) now2 - (int64_t) pa_bytes_to_usec((uint64_t) u->frame_index * u->frame_size, &u->source->sample_spec);
+
+    if (delay > 0)
+        r = (pa_usec_t) delay;
 
     return r;
 }
 
 static int build_pollfd(struct userdata *u) {
-    int err;
-    struct pollfd *pollfd;
-    int n;
-    
     pa_assert(u);
     pa_assert(u->pcm_handle);
 
-    if ((n = snd_pcm_poll_descriptors_count(u->pcm_handle)) < 0) {
-        pa_log("snd_pcm_poll_descriptors_count() failed: %s", snd_strerror(n));
-        return -1;
-    }
-
     if (u->alsa_rtpoll_item)
         pa_rtpoll_item_free(u->alsa_rtpoll_item);
 
-    u->alsa_rtpoll_item = pa_rtpoll_item_new(u->rtpoll, n);
-    pollfd = pa_rtpoll_item_get_pollfd(u->alsa_rtpoll_item, NULL);
-    
-    if ((err = snd_pcm_poll_descriptors(u->pcm_handle, pollfd, n)) < 0) {
-        pa_log("snd_pcm_poll_descriptors() failed: %s", snd_strerror(err));
+    if (!(u->alsa_rtpoll_item = pa_alsa_build_pollfd(u->pcm_handle, u->rtpoll)))
         return -1;
-    }
-    
+
     return 0;
 }
 
@@ -319,6 +502,8 @@ static int suspend(struct userdata *u) {
     pa_assert(u);
     pa_assert(u->pcm_handle);
 
+    pa_smoother_pause(u->smoother, pa_rtclock_usec());
+
     /* Let's suspend */
     snd_pcm_close(u->pcm_handle);
     u->pcm_handle = NULL;
@@ -327,15 +512,69 @@ static int suspend(struct userdata *u) {
         pa_rtpoll_item_free(u->alsa_rtpoll_item);
         u->alsa_rtpoll_item = NULL;
     }
-    
+
     pa_log_info("Device suspended...");
-    
+
+    return 0;
+}
+
+static int update_sw_params(struct userdata *u) {
+    snd_pcm_uframes_t avail_min;
+    int err;
+
+    pa_assert(u);
+
+    /* Use the full buffer if noone asked us for anything specific */
+    u->hwbuf_unused_frames = 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_frames = (snd_pcm_sframes_t)
+                (PA_LIKELY(b < u->hwbuf_size) ?
+                 ((u->hwbuf_size - b) / u->frame_size) : 0);
+        }
+
+        fix_tsched_watermark(u);
+    }
+
+    pa_log_debug("hwbuf_unused_frames=%lu", (unsigned long) u->hwbuf_unused_frames);
+
+    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);
+    }
+
+    pa_log_debug("setting avail_min=%lu", (unsigned long) avail_min);
+
+    if ((err = pa_alsa_set_sw_params(u->pcm_handle, avail_min)) < 0) {
+        pa_log("Failed to set software parameters: %s", snd_strerror(err));
+        return err;
+    }
+
     return 0;
 }
 
 static int unsuspend(struct userdata *u) {
     pa_sample_spec ss;
-    int err, b;
+    int err;
+    pa_bool_t b, d;
     unsigned nfrags;
     snd_pcm_uframes_t period_size;
 
@@ -345,7 +584,12 @@ static int unsuspend(struct userdata *u) {
     pa_log_info("Trying resume...");
 
     snd_config_update_free_global();
-    if ((err = snd_pcm_open(&u->pcm_handle, u->device_name, SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK)) < 0) {
+
+    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) {
         pa_log("Error opening PCM device %s: %s", u->device_name, snd_strerror(err));
         goto fail;
     }
@@ -354,39 +598,41 @@ static int unsuspend(struct userdata *u) {
     nfrags = u->nfragments;
     period_size = u->fragment_size / u->frame_size;
     b = u->use_mmap;
-    
-    if ((err = pa_alsa_set_hw_params(u->pcm_handle, &ss, &nfrags, &period_size, &b)) < 0) {
+    d = u->use_tsched;
+
+    if ((err = pa_alsa_set_hw_params(u->pcm_handle, &ss, &nfrags, &period_size, u->hwbuf_size / u->frame_size, &b, &d, TRUE)) < 0) {
         pa_log("Failed to set hardware parameters: %s", snd_strerror(err));
         goto fail;
     }
 
-    if (b != u->use_mmap) {
+    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 (nfrags != u->nfragments || period_size*u->frame_size != u->fragment_size) {
-        pa_log_warn("Resume failed, couldn't restore original fragment settings.");
+        pa_log_warn("Resume failed, couldn't restore original fragment settings. (Old: %lu*%lu, New %lu*%lu)",
+                    (unsigned long) u->nfragments, (unsigned long) u->fragment_size,
+                    (unsigned long) nfrags, period_size * u->frame_size);
         goto fail;
     }
 
-    if ((err = pa_alsa_set_sw_params(u->pcm_handle)) < 0) {
-        pa_log("Failed to set software parameters: %s", snd_strerror(err));
+    if (update_sw_params(u) < 0)
         goto fail;
-    }
 
     if (build_pollfd(u) < 0)
         goto fail;
-    
-    snd_pcm_start(u->pcm_handle);
-    
+
     /* FIXME: We need to reload the volume somehow */
-                
+
+    snd_pcm_start(u->pcm_handle);
+    pa_smoother_resume(u->smoother, pa_rtclock_usec());
+
     pa_log_info("Resumed successfully...");
 
     return 0;
@@ -419,30 +665,37 @@ static int source_process_msg(pa_msgobject *o, int code, void *data, int64_t off
         case PA_SOURCE_MESSAGE_SET_STATE:
 
             switch ((pa_source_state_t) PA_PTR_TO_UINT(data)) {
-                
+
                 case PA_SOURCE_SUSPENDED:
-                    pa_assert(PA_SOURCE_OPENED(u->source->thread_info.state));
+                    pa_assert(PA_SOURCE_IS_OPENED(u->source->thread_info.state));
 
                     if (suspend(u) < 0)
                         return -1;
-                    
+
                     break;
 
                 case PA_SOURCE_IDLE:
                 case PA_SOURCE_RUNNING:
 
+                    if (u->source->thread_info.state == PA_SOURCE_INIT) {
+                        if (build_pollfd(u) < 0)
+                            return -1;
+
+                        snd_pcm_start(u->pcm_handle);
+                    }
+
                     if (u->source->thread_info.state == PA_SOURCE_SUSPENDED) {
                         if (unsuspend(u) < 0)
                             return -1;
                     }
-                    
+
                     break;
 
                 case PA_SOURCE_UNLINKED:
                 case PA_SOURCE_INIT:
                     ;
             }
-            
+
             break;
     }
 
@@ -459,78 +712,215 @@ static int mixer_callback(snd_mixer_elem_t *elem, unsigned int mask) {
         return 0;
 
     if (mask & SND_CTL_EVENT_MASK_VALUE) {
-        pa_source_get_volume(u->source);
-        pa_source_get_mute(u->source);
+        pa_source_get_volume(u->source, TRUE);
+        pa_source_get_mute(u->source, TRUE);
     }
 
     return 0;
 }
 
+static pa_volume_t from_alsa_volume(struct userdata *u, long alsa_vol) {
+
+    return (pa_volume_t) round(((double) (alsa_vol - u->hw_volume_min) * PA_VOLUME_NORM) /
+                               (double) (u->hw_volume_max - u->hw_volume_min));
+}
+
+static long to_alsa_volume(struct userdata *u, pa_volume_t vol) {
+    long alsa_vol;
+
+    alsa_vol = (long) round(((double) vol * (double) (u->hw_volume_max - u->hw_volume_min))
+                            / PA_VOLUME_NORM) + u->hw_volume_min;
+
+    return PA_CLAMP_UNLIKELY(alsa_vol, u->hw_volume_min, u->hw_volume_max);
+}
+
 static int source_get_volume_cb(pa_source *s) {
     struct userdata *u = s->userdata;
     int err;
-    int i;
+    unsigned i;
+    pa_cvolume r;
+    char t[PA_CVOLUME_SNPRINT_MAX];
 
     pa_assert(u);
     pa_assert(u->mixer_elem);
 
-    for (i = 0; i < s->sample_spec.channels; i++) {
-        long set_vol, vol;
+    if (u->mixer_seperate_channels) {
 
-        pa_assert(snd_mixer_selem_has_capture_channel(u->mixer_elem, i));
+        r.channels = s->sample_spec.channels;
 
-        if ((err = snd_mixer_selem_get_capture_volume(u->mixer_elem, i, &vol)) < 0)
-            goto fail;
+        for (i = 0; i < s->sample_spec.channels; i++) {
+            long alsa_vol;
+
+            if (u->hw_dB_supported) {
+
+                if ((err = snd_mixer_selem_get_capture_dB(u->mixer_elem, u->mixer_map[i], &alsa_vol)) < 0)
+                    goto fail;
+
+#ifdef HAVE_VALGRIND_MEMCHECK_H
+                VALGRIND_MAKE_MEM_DEFINED(&alsa_vol, sizeof(alsa_vol));
+#endif
+
+                r.values[i] = pa_sw_volume_from_dB((double) (alsa_vol - u->hw_dB_max) / 100.0);
+            } else {
+
+                if ((err = snd_mixer_selem_get_capture_volume(u->mixer_elem, u->mixer_map[i], &alsa_vol)) < 0)
+                    goto fail;
+
+                r.values[i] = from_alsa_volume(u, alsa_vol);
+            }
+        }
+
+    } else {
+        long alsa_vol;
+
+        if (u->hw_dB_supported) {
+
+            if ((err = snd_mixer_selem_get_capture_dB(u->mixer_elem, SND_MIXER_SCHN_MONO, &alsa_vol)) < 0)
+                goto fail;
+
+#ifdef HAVE_VALGRIND_MEMCHECK_H
+            VALGRIND_MAKE_MEM_DEFINED(&alsa_vol, sizeof(alsa_vol));
+#endif
+
+            pa_cvolume_set(&r, s->sample_spec.channels, pa_sw_volume_from_dB((double) (alsa_vol - u->hw_dB_max) / 100.0));
+
+        } else {
+
+            if ((err = snd_mixer_selem_get_capture_volume(u->mixer_elem, SND_MIXER_SCHN_MONO, &alsa_vol)) < 0)
+                goto fail;
+
+            pa_cvolume_set(&r, s->sample_spec.channels, from_alsa_volume(u, alsa_vol));
+        }
+    }
+
+    pa_log_debug("Read hardware volume: %s", pa_cvolume_snprint(t, sizeof(t), &r));
+
+    if (!pa_cvolume_equal(&u->hardware_volume, &r)) {
 
-        set_vol = (long) roundf(((float) s->volume.values[i] * (u->hw_volume_max - u->hw_volume_min)) / PA_VOLUME_NORM) + u->hw_volume_min;
+        u->hardware_volume = s->volume = r;
 
-        /* Try to avoid superfluous volume changes */
-        if (set_vol != vol)
-            s->volume.values[i] = (pa_volume_t) roundf(((float) (vol - u->hw_volume_min) * PA_VOLUME_NORM) / (u->hw_volume_max - u->hw_volume_min));
+        if (u->hw_dB_supported) {
+            pa_cvolume reset;
+
+            /* Hmm, so the hardware volume changed, let's reset our software volume */
+
+            pa_cvolume_reset(&reset, s->sample_spec.channels);
+            pa_source_set_soft_volume(s, &reset);
+        }
     }
 
     return 0;
 
 fail:
     pa_log_error("Unable to read volume: %s", snd_strerror(err));
-    
-    s->get_volume = NULL;
-    s->set_volume = NULL;
+
     return -1;
 }
 
 static int source_set_volume_cb(pa_source *s) {
     struct userdata *u = s->userdata;
     int err;
-    int i;
+    unsigned i;
+    pa_cvolume r;
 
     pa_assert(u);
     pa_assert(u->mixer_elem);
 
-    for (i = 0; i < s->sample_spec.channels; i++) {
-        long alsa_vol;
+    if (u->mixer_seperate_channels) {
+
+        r.channels = s->sample_spec.channels;
+
+        for (i = 0; i < s->sample_spec.channels; i++) {
+            long alsa_vol;
+            pa_volume_t vol;
+
+            vol = s->volume.values[i];
+
+            if (u->hw_dB_supported) {
+
+                alsa_vol = (long) (pa_sw_volume_to_dB(vol) * 100);
+                alsa_vol += u->hw_dB_max;
+                alsa_vol = PA_CLAMP_UNLIKELY(alsa_vol, u->hw_dB_min, u->hw_dB_max);
+
+                if ((err = snd_mixer_selem_set_capture_dB(u->mixer_elem, u->mixer_map[i], alsa_vol, 1)) < 0)
+                    goto fail;
+
+                if ((err = snd_mixer_selem_get_capture_dB(u->mixer_elem, u->mixer_map[i], &alsa_vol)) < 0)
+                    goto fail;
+
+                r.values[i] = pa_sw_volume_from_dB((double) (alsa_vol - u->hw_dB_max) / 100.0);
+
+            } else {
+                alsa_vol = to_alsa_volume(u, vol);
+
+                if ((err = snd_mixer_selem_set_capture_volume(u->mixer_elem, u->mixer_map[i], alsa_vol)) < 0)
+                    goto fail;
+
+                if ((err = snd_mixer_selem_get_capture_volume(u->mixer_elem, u->mixer_map[i], &alsa_vol)) < 0)
+                    goto fail;
+
+                r.values[i] = from_alsa_volume(u, alsa_vol);
+            }
+        }
+
+    } else {
         pa_volume_t vol;
+        long alsa_vol;
 
-        pa_assert(snd_mixer_selem_has_capture_channel(u->mixer_elem, i));
+        vol = pa_cvolume_max(&s->volume);
 
-        vol = s->volume.values[i];
+        if (u->hw_dB_supported) {
+            alsa_vol = (long) (pa_sw_volume_to_dB(vol) * 100);
+            alsa_vol += u->hw_dB_max;
+            alsa_vol = PA_CLAMP_UNLIKELY(alsa_vol, u->hw_dB_min, u->hw_dB_max);
 
-        if (vol > PA_VOLUME_NORM)
-            vol = PA_VOLUME_NORM;
+            if ((err = snd_mixer_selem_set_capture_dB_all(u->mixer_elem, alsa_vol, 1)) < 0)
+                goto fail;
 
-        alsa_vol = (long) roundf(((float) vol * (u->hw_volume_max - u->hw_volume_min)) / PA_VOLUME_NORM) + u->hw_volume_min;
+            if ((err = snd_mixer_selem_get_capture_dB(u->mixer_elem, SND_MIXER_SCHN_MONO, &alsa_vol)) < 0)
+                goto fail;
 
-        if ((err = snd_mixer_selem_set_capture_volume(u->mixer_elem, i, alsa_vol)) < 0)
-            goto fail;
+            pa_cvolume_set(&r, s->volume.channels, pa_sw_volume_from_dB((double) (alsa_vol - u->hw_dB_max) / 100.0));
+
+        } else {
+            alsa_vol = to_alsa_volume(u, vol);
+
+            if ((err = snd_mixer_selem_set_capture_volume_all(u->mixer_elem, alsa_vol)) < 0)
+                goto fail;
+
+            if ((err = snd_mixer_selem_get_capture_volume(u->mixer_elem, SND_MIXER_SCHN_MONO, &alsa_vol)) < 0)
+                goto fail;
+
+            pa_cvolume_set(&r, s->sample_spec.channels, from_alsa_volume(u, alsa_vol));
+        }
     }
 
+    u->hardware_volume = r;
+
+    if (u->hw_dB_supported) {
+        char t[PA_CVOLUME_SNPRINT_MAX];
+
+        /* Match exactly what the user requested by software */
+
+        pa_sw_cvolume_divide(&r, &s->volume, &r);
+        pa_source_set_soft_volume(s, &r);
+
+        pa_log_debug("Requested volume: %s", pa_cvolume_snprint(t, sizeof(t), &s->volume));
+        pa_log_debug("Got hardware volume: %s", pa_cvolume_snprint(t, sizeof(t), &u->hardware_volume));
+        pa_log_debug("Calculated software volume: %s", pa_cvolume_snprint(t, sizeof(t), &r));
+
+    } else
+
+        /* We can't match exactly what the user requested, hence let's
+         * at least tell the user about it */
+
+        s->volume = r;
+
     return 0;
 
 fail:
     pa_log_error("Unable to set volume: %s", snd_strerror(err));
-    
-    s->get_volume = NULL;
-    s->set_volume = NULL;
+
     return -1;
 }
 
@@ -543,9 +933,6 @@ static int source_get_mute_cb(pa_source *s) {
 
     if ((err = snd_mixer_selem_get_capture_switch(u->mixer_elem, 0, &sw)) < 0) {
         pa_log_error("Unable to get switch: %s", snd_strerror(err));
-
-        s->get_mute = NULL;
-        s->set_mute = NULL;
         return -1;
     }
 
@@ -563,97 +950,117 @@ static int source_set_mute_cb(pa_source *s) {
 
     if ((err = snd_mixer_selem_set_capture_switch_all(u->mixer_elem, !s->muted)) < 0) {
         pa_log_error("Unable to set switch: %s", snd_strerror(err));
-        
-        s->get_mute = NULL;
-        s->set_mute = NULL;
         return -1;
     }
 
     return 0;
 }
 
+static void source_update_requested_latency_cb(pa_source *s) {
+    struct userdata *u = s->userdata;
+    pa_assert(u);
+
+    if (!u->pcm_handle)
+        return;
+
+    update_sw_params(u);
+}
+
 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->high_priority)
-        pa_make_realtime();
+    if (u->core->realtime_scheduling)
+        pa_make_realtime(u->core->realtime_priority);
 
     pa_thread_mq_install(&u->thread_mq);
     pa_rtpoll_install(u->rtpoll);
-    
-    if (build_pollfd(u) < 0)
-        goto fail;
 
-    snd_pcm_start(u->pcm_handle);
-    
     for (;;) {
         int ret;
 
+/*         pa_log_debug("loop"); */
+
         /* Read some data and pass it to the sources */
-        if (PA_SOURCE_OPENED(u->source->thread_info.state)) {
-            
-            if (u->use_mmap) {
-                if (mmap_read(u) < 0)
-                    goto fail;
+        if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
+            int work_done = 0;
+            pa_usec_t sleep_usec = 0;
 
-            } else {
-                if (unix_read(u) < 0)
-                    goto fail;
+            if (u->use_mmap)
+                work_done = mmap_read(u, &sleep_usec, revents & POLLIN);
+            else
+                work_done = unix_read(u, &sleep_usec, revents & POLLIN);
+
+            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_usec(), 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 */
+                pa_rtpoll_set_timer_relative(u->rtpoll, PA_MIN(sleep_usec, cusec));
             }
-        }
+        } else if (u->use_tsched)
 
-        /* Now give the source outputs some to time to process their data */
-        if ((ret = pa_source_process_outputs(u->source)) < 0)
-            goto fail;
-        if (ret > 0)
-            continue;
-        
-        /* Check whether there is a message for us to process */
-        if ((ret = pa_thread_mq_process(&u->thread_mq) < 0))
-            goto finish;
-        if (ret > 0)
-            continue;
+            /* OK, we're in an invalid state, let's disable our timers */
+            pa_rtpoll_set_timer_disabled(u->rtpoll);
 
         /* Hmm, nothing to do. Let's sleep */
-        if (pa_rtpoll_run(u->rtpoll) < 0) {
-            pa_log("poll() failed: %s", pa_cstrerror(errno));
+        if ((ret = pa_rtpoll_run(u->rtpoll, TRUE)) < 0)
             goto fail;
-        }
+
+        if (ret == 0)
+            goto finish;
 
         /* Tell ALSA about this and process its response */
-        if (PA_SOURCE_OPENED(u->source->thread_info.state)) {
+        if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
             struct pollfd *pollfd;
-            unsigned short revents = 0;
             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", snd_strerror(err));
                 goto fail;
             }
 
-            if (revents & (POLLERR|POLLNVAL|POLLHUP)) {
-                if (revents & POLLERR)
-                    pa_log_warn("Got POLLERR from ALSA");
-                if (revents & POLLNVAL)
-                    pa_log_warn("Got POLLNVAL from ALSA"); 
-                if (revents & POLLHUP)
-                    pa_log_warn("Got POLLHUP from ALSA");
+            if (revents & (POLLOUT|POLLERR|POLLNVAL|POLLHUP|POLLPRI)) {
+                if (pa_alsa_recover_from_poll(u->pcm_handle, revents) < 0)
+                    goto fail;
 
-                goto fail;
+                snd_pcm_start(u->pcm_handle);
             }
-        }
+
+            if (revents && u->use_tsched)
+                pa_log_debug("Wakeup from ALSA!%s%s", (revents & POLLIN) ? " INPUT" : "", (revents & POLLOUT) ? " OUTPUT" : "");
+        } else
+            revents = 0;
     }
 
 fail:
-    /* We have to continue processing messages until we receive the
-     * SHUTDOWN message */
+    /* 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);
 
@@ -662,27 +1069,29 @@ finish:
 }
 
 int pa__init(pa_module*m) {
-    
+
     pa_modargs *ma = NULL;
     struct userdata *u = NULL;
-    const char *dev;
+    const char *dev_id;
     pa_sample_spec ss;
     pa_channel_map map;
-    unsigned nfrags, frag_size;
-    snd_pcm_uframes_t period_size;
+    uint32_t nfrags, hwbuf_size, frag_size, tsched_size, tsched_watermark;
+    snd_pcm_uframes_t period_frames, tsched_frames;
     size_t frame_size;
     snd_pcm_info_t *pcm_info = NULL;
     int err;
-    char *t;
     const char *name;
     char *name_buf = NULL;
-    int namereg_fail;
-    int use_mmap = 1, b;
+    pa_bool_t namereg_fail;
+    pa_bool_t use_mmap = TRUE, b, use_tsched = TRUE, d;
+    pa_source_new_data data;
 
     snd_pcm_info_alloca(&pcm_info);
 
     pa_assert(m);
-    
+
+    pa_alsa_redirect_errors_inc();
+
     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
         pa_log("Failed to parse module arguments");
         goto fail;
@@ -697,186 +1106,338 @@ int pa__init(pa_module*m) {
     frame_size = pa_frame_size(&ss);
 
     nfrags = m->core->default_n_fragments;
-    frag_size = pa_usec_to_bytes(m->core->default_fragment_size_msec*1000, &ss);
+    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 = frame_size;
-
-    if (pa_modargs_get_value_u32(ma, "fragments", &nfrags) < 0 || pa_modargs_get_value_u32(ma, "fragment_size", &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;
     }
-    period_size = frag_size/frame_size;
+
+    hwbuf_size = frag_size * nfrags;
+    period_frames = frag_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 timer_scheduling argument.");
+        goto fail;
+    }
+
+    if (use_tsched && !pa_rtclock_hrtimer()) {
+        pa_log_notice("Disabling timer-based scheduling because high-resolution timers are not available from the kernel.");
+        use_tsched = FALSE;
+    }
+
     u = pa_xnew0(struct userdata, 1);
     u->core = m->core;
     u->module = m;
     m->userdata = u;
     u->use_mmap = use_mmap;
-    pa_thread_mq_init(&u->thread_mq, m->core->mainloop);
+    u->use_tsched = use_tsched;
     u->rtpoll = pa_rtpoll_new();
+    pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll);
     u->alsa_rtpoll_item = NULL;
-    pa_rtpoll_item_new_asyncmsgq(u->rtpoll, u->thread_mq.inq);
+
+    u->smoother = pa_smoother_new(DEFAULT_TSCHED_WATERMARK_USEC, DEFAULT_TSCHED_WATERMARK_USEC, TRUE, 5);
+    pa_smoother_set_time_offset(u->smoother, pa_rtclock_usec());
 
     snd_config_update_free_global();
-    if ((err = snd_pcm_open(&u->pcm_handle, dev = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK)) < 0) {
-        pa_log("Error opening PCM device %s: %s", dev, snd_strerror(err));
-        goto fail;
-    }
 
-    u->device_name = pa_xstrdup(dev);
+    b = use_mmap;
+    d = use_tsched;
 
-    if ((err = snd_pcm_info(u->pcm_handle, pcm_info)) < 0) {
-        pa_log("Error fetching PCM info: %s", snd_strerror(err));
-        goto fail;
-    }
+    if ((dev_id = pa_modargs_get_value(ma, "device_id", NULL))) {
 
-    b = use_mmap;
-    if ((err = pa_alsa_set_hw_params(u->pcm_handle, &ss, &nfrags, &period_size, &b)) < 0) {
-        pa_log("Failed to set hardware parameters: %s", snd_strerror(err));
-        goto fail;
+        if (!(u->pcm_handle = pa_alsa_open_by_device_id(
+                      dev_id,
+                      &u->device_name,
+                      &ss, &map,
+                      SND_PCM_STREAM_CAPTURE,
+                      &nfrags, &period_frames, tsched_frames,
+                      &b, &d)))
+            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,
+                      &nfrags, &period_frames, tsched_frames,
+                      &b, &d)))
+            goto fail;
     }
 
+    pa_assert(u->device_name);
+    pa_log_info("Successfully opened device %s.", u->device_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 = b;
+        u->use_mmap = use_mmap = FALSE;
+    }
+
+    if (use_tsched && (!b || !d)) {
+        pa_log_info("Cannot enabled 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 ((err = pa_alsa_set_sw_params(u->pcm_handle)) < 0) {
-        pa_log("Failed to set software parameters: %s", snd_strerror(err));
+    if (u->use_tsched)
+        pa_log_info("Successfully enabled timer-based scheduling mode.");
+
+    if ((err = snd_pcm_info(u->pcm_handle, pcm_info)) < 0) {
+        pa_log("Error fetching PCM info: %s", snd_strerror(err));
         goto fail;
     }
-    
+
     /* ALSA might tweak the sample spec, so recalculate the frame size */
     frame_size = pa_frame_size(&ss);
 
-    if (ss.channels != map.channels)
-        /* Seems ALSA didn't like the channel number, so let's fix the channel map */
-        pa_channel_map_init_auto(&map, ss.channels, PA_CHANNEL_MAP_ALSA);
-
     if ((err = snd_mixer_open(&u->mixer_handle, 0)) < 0)
         pa_log("Error opening mixer: %s", snd_strerror(err));
     else {
-        
-        if ((pa_alsa_prepare_mixer(u->mixer_handle, dev) < 0) ||
-            !(u->mixer_elem = pa_alsa_find_elem(u->mixer_handle, "Capture", NULL))) {
+        pa_bool_t found = FALSE;
+
+        if (pa_alsa_prepare_mixer(u->mixer_handle, u->device_name) >= 0)
+            found = TRUE;
+        else {
+            snd_pcm_info_t* info;
+
+            snd_pcm_info_alloca(&info);
+
+            if (snd_pcm_info(u->pcm_handle, info) >= 0) {
+                char *md;
+                int card;
+
+                if ((card = snd_pcm_info_get_card(info)) >= 0) {
+
+                    md = pa_sprintf_malloc("hw:%i", card);
+
+                    if (strcmp(u->device_name, md))
+                        if (pa_alsa_prepare_mixer(u->mixer_handle, md) >= 0)
+                            found = TRUE;
+                    pa_xfree(md);
+                }
+            }
+        }
+
+        if (found)
+            if (!(u->mixer_elem = pa_alsa_find_elem(u->mixer_handle, "Capture", "Mic", FALSE)))
+                found = FALSE;
+
+        if (!found) {
             snd_mixer_close(u->mixer_handle);
             u->mixer_handle = NULL;
         }
     }
 
     if ((name = pa_modargs_get_value(ma, "source_name", NULL)))
-        namereg_fail = 1;
+        namereg_fail = TRUE;
     else {
-        name = name_buf = pa_sprintf_malloc("alsa_input.%s", dev);
-        namereg_fail = 0;
+        name = name_buf = pa_sprintf_malloc("alsa_input.%s", u->device_name);
+        namereg_fail = FALSE;
     }
 
-    u->source = pa_source_new(m->core, __FILE__, name, namereg_fail, &ss, &map);
+    pa_source_new_data_init(&data);
+    data.driver = __FILE__;
+    data.module = m;
+    pa_source_new_data_set_name(&data, name);
+    data.namereg_fail = namereg_fail;
+    pa_source_new_data_set_sample_spec(&data, &ss);
+    pa_source_new_data_set_channel_map(&data, &map);
+
+    pa_alsa_init_proplist(data.proplist, pcm_info);
+    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) (period_frames * frame_size * nfrags));
+    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"));
+
+    u->source = pa_source_new(m->core, &data, PA_SOURCE_HARDWARE|PA_SOURCE_LATENCY);
+    pa_source_new_data_done(&data);
     pa_xfree(name_buf);
-    
+
     if (!u->source) {
         pa_log("Failed to create source object");
         goto fail;
     }
 
     u->source->parent.process_msg = source_process_msg;
+    u->source->update_requested_latency = source_update_requested_latency_cb;
     u->source->userdata = u;
 
-    pa_source_set_module(u->source, m);
     pa_source_set_asyncmsgq(u->source, u->thread_mq.inq);
     pa_source_set_rtpoll(u->source, u->rtpoll);
-    pa_source_set_description(u->source, t = pa_sprintf_malloc(
-                                      "ALSA PCM on %s (%s)%s",
-                                      dev,
-                                      snd_pcm_info_get_name(pcm_info),
-                                      use_mmap ? " via DMA" : ""));
-    pa_xfree(t);
-
-    u->source->flags = PA_SOURCE_HARDWARE|PA_SOURCE_CAN_SUSPEND|PA_SOURCE_LATENCY|PA_SOURCE_HW_VOLUME_CTRL;
 
     u->frame_size = frame_size;
-    u->fragment_size = frag_size = period_size * frame_size;
+    u->fragment_size = frag_size = (uint32_t) (period_frames * frame_size);
     u->nfragments = nfrags;
     u->hwbuf_size = u->fragment_size * nfrags;
-
-    pa_log_info("Using %u fragments of size %lu bytes.", nfrags, (long unsigned) u->fragment_size);
+    u->hwbuf_unused_frames = 0;
+    u->tsched_watermark = tsched_watermark;
+    u->frame_index = 0;
+    u->hw_dB_supported = FALSE;
+    u->hw_dB_min = u->hw_dB_max = 0;
+    u->hw_volume_min = u->hw_volume_max = 0;
+    u->mixer_seperate_channels = FALSE;
+    pa_cvolume_mute(&u->hardware_volume, u->source->sample_spec.channels);
+
+    if (use_tsched)
+        fix_tsched_watermark(u);
+
+    pa_source_set_latency_range(u->source,
+                                !use_tsched ? pa_bytes_to_usec(u->hwbuf_size, &ss) : (pa_usec_t) -1,
+                                pa_bytes_to_usec(u->hwbuf_size, &ss));
+
+    pa_log_info("Using %u fragments of size %lu bytes, buffer time is %0.2fms",
+                nfrags, (long unsigned) u->fragment_size,
+                (double) pa_bytes_to_usec(u->hwbuf_size, &ss) / PA_USEC_PER_MSEC);
+
+    if (use_tsched)
+        pa_log_info("Time scheduling watermark is %0.2fms",
+                    (double) pa_bytes_to_usec(u->tsched_watermark, &ss) / PA_USEC_PER_MSEC);
+
+    if (update_sw_params(u) < 0)
+        goto fail;
 
     if (u->mixer_handle) {
-        assert(u->mixer_elem);
-        
+        pa_assert(u->mixer_elem);
+
         if (snd_mixer_selem_has_capture_volume(u->mixer_elem)) {
-            int i;
+            pa_bool_t suitable = FALSE;
+
+            if (snd_mixer_selem_get_capture_volume_range(u->mixer_elem, &u->hw_volume_min, &u->hw_volume_max) < 0)
+                pa_log_info("Failed to get volume range. Falling back to software volume control.");
+            else if (u->hw_volume_min >= u->hw_volume_max)
+                pa_log_warn("Your kernel driver is broken: it reports a volume range from %li to %li which makes no sense.", u->hw_volume_min, u->hw_volume_max);
+            else {
+                pa_log_info("Volume ranges from %li to %li.", u->hw_volume_min, u->hw_volume_max);
+                suitable = TRUE;
+            }
 
-            for (i = 0;i < ss.channels;i++) {
-                if (!snd_mixer_selem_has_capture_channel(u->mixer_elem, i))
-                    break;
+            if (suitable) {
+                if (snd_mixer_selem_get_capture_dB_range(u->mixer_elem, &u->hw_dB_min, &u->hw_dB_max) < 0)
+                    pa_log_info("Mixer doesn't support dB information.");
+                else {
+#ifdef HAVE_VALGRIND_MEMCHECK_H
+                    VALGRIND_MAKE_MEM_DEFINED(&u->hw_dB_min, sizeof(u->hw_dB_min));
+                    VALGRIND_MAKE_MEM_DEFINED(&u->hw_dB_max, sizeof(u->hw_dB_max));
+#endif
+
+                    if (u->hw_dB_min >= u->hw_dB_max)
+                        pa_log_warn("Your kernel driver is broken: it reports a volume range from %0.2f dB to %0.2f dB which makes no sense.", (double) u->hw_dB_min/100.0, (double) u->hw_dB_max/100.0);
+                    else {
+                        pa_log_info("Volume ranges from %0.2f dB to %0.2f dB.", (double) u->hw_dB_min/100.0, (double) u->hw_dB_max/100.0);
+                        u->hw_dB_supported = TRUE;
+
+                        if (u->hw_dB_max > 0) {
+                            u->source->base_volume = pa_sw_volume_from_dB(- (double) u->hw_dB_max/100.0);
+                            pa_log_info("Fixing base volume to %0.2f dB", pa_sw_volume_to_dB(u->source->base_volume));
+                        } else
+                            pa_log_info("No particular base volume set, fixing to 0 dB");
+
+                    }
+                }
+
+                if (!u->hw_dB_supported &&
+                    u->hw_volume_max - u->hw_volume_min < 3) {
+
+                    pa_log_info("Device has less than 4 volume levels. Falling back to software volume control.");
+                    suitable = FALSE;
+                }
             }
 
-            if (i == ss.channels) {
+            if (suitable) {
+                u->mixer_seperate_channels = pa_alsa_calc_mixer_map(u->mixer_elem, &map, u->mixer_map, FALSE) >= 0;
+
                 u->source->get_volume = source_get_volume_cb;
                 u->source->set_volume = source_set_volume_cb;
-                snd_mixer_selem_get_capture_volume_range(u->mixer_elem, &u->hw_volume_min, &u->hw_volume_max);
-            }
+                u->source->flags |= PA_SOURCE_HW_VOLUME_CTRL | (u->hw_dB_supported ? PA_SOURCE_DECIBEL_VOLUME : 0);
+                pa_log_info("Using hardware volume control. Hardware dB scale %s.", u->hw_dB_supported ? "supported" : "not supported");
+            } else
+                pa_log_info("Using software volume control.");
         }
-        
+
         if (snd_mixer_selem_has_capture_switch(u->mixer_elem)) {
             u->source->get_mute = source_get_mute_cb;
             u->source->set_mute = source_set_mute_cb;
-        }
+            u->source->flags |= PA_SOURCE_HW_MUTE_CTRL;
+        } else
+            pa_log_info("Using software mute control.");
 
         u->mixer_fdl = pa_alsa_fdlist_new();
-        
+
         if (pa_alsa_fdlist_set_mixer(u->mixer_fdl, u->mixer_handle, m->core->mainloop) < 0) {
-            pa_log("failed to initialise file descriptor monitoring");
+            pa_log("Failed to initialize file descriptor monitoring");
             goto fail;
         }
-        
+
         snd_mixer_elem_set_callback(u->mixer_elem, mixer_callback);
         snd_mixer_elem_set_callback_private(u->mixer_elem, u);
     } else
         u->mixer_fdl = NULL;
 
+    pa_alsa_dump(u->pcm_handle);
+
     if (!(u->thread = pa_thread_new(thread_func, u))) {
         pa_log("Failed to create thread.");
         goto fail;
     }
     /* Get initial mixer settings */
-    if (u->source->get_volume)
-        u->source->get_volume(u->source);
-    if (u->source->get_mute)
-        u->source->get_mute(u->source);
+    if (data.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 (data.muted_is_set) {
+        if (u->source->set_mute)
+            u->source->set_mute(u->source);
+    } else {
+        if (u->source->get_mute)
+            u->source->get_mute(u->source);
+    }
+
+    pa_source_put(u->source);
 
-    pa_source_put(u->source);    
-    
     pa_modargs_free(ma);
-    
+
     return 0;
-    
+
 fail:
 
     if (ma)
         pa_modargs_free(ma);
 
     pa__done(m);
-    
+
     return -1;
 }
 
 void pa__done(pa_module*m) {
     struct userdata *u;
-    
+
     pa_assert(m);
 
-    if (!(u = m->userdata))
+    if (!(u = m->userdata)) {
+        pa_alsa_redirect_errors_dec();
         return;
+    }
 
     if (u->source)
         pa_source_unlink(u->source);
@@ -893,10 +1454,10 @@ void pa__done(pa_module*m) {
 
     if (u->alsa_rtpoll_item)
         pa_rtpoll_item_free(u->alsa_rtpoll_item);
-    
+
     if (u->rtpoll)
         pa_rtpoll_free(u->rtpoll);
-    
+
     if (u->mixer_fdl)
         pa_alsa_fdlist_free(u->mixer_fdl);
 
@@ -908,9 +1469,12 @@ void pa__done(pa_module*m) {
         snd_pcm_close(u->pcm_handle);
     }
 
+    if (u->smoother)
+        pa_smoother_free(u->smoother);
+
     pa_xfree(u->device_name);
     pa_xfree(u);
 
     snd_config_update_free_global();
+    pa_alsa_redirect_errors_dec();
 }
-