11 files changed, 259 insertions, 27 deletions

diff --git a/apps/lang/english.lang b/apps/lang/english.lang
index fc575a3764..7366a80030 100644
--- a/apps/lang/english.lang
+++ b/apps/lang/english.lang
@@ -13052,3 +13052,37 @@
     *: "Western European"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_CROSSFEED_MEIER
+  desc: in sound settings
+  user: core
+  <source>
+    *: none
+    swcodec: "Simple (Meier)"
+  </source>
+  <dest>
+    *: none
+    swcodec: "Simple (Meier)"
+  </dest>
+  <voice>
+    *: none
+    swcodec: "Simple"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_CROSSFEED_CUSTOM
+  desc: in sound settings
+  user: core
+  <source>
+    *: none
+    swcodec: "Custom"
+  </source>
+  <dest>
+    *: none
+    swcodec: "Custom"
+  </dest>
+  <voice>
+    *: none
+    swcodec: "Custom"
+  </voice>
+</phrase>
diff --git a/apps/plugin.c b/apps/plugin.c
index afb336ebdc..e0e565e504 100644
--- a/apps/plugin.c
+++ b/apps/plugin.c
@@ -565,7 +565,7 @@ static const struct plugin_api rockbox_api = {
     audio_set_output_source,
     audio_set_input_source,
 #endif
-    dsp_crossfeed_enable,
+    dsp_set_crossfeed_type ,
     dsp_eq_enable,
     dsp_dither_enable,
 #ifdef HAVE_PITCHCONTROL
diff --git a/apps/plugin.h b/apps/plugin.h
index b1d3c16979..bb2778164b 100644
--- a/apps/plugin.h
+++ b/apps/plugin.h
@@ -682,7 +682,7 @@ struct plugin_api {
     void (*audio_set_output_source)(int monitor);
     void (*audio_set_input_source)(int source, unsigned flags);
 #endif
-    void (*dsp_crossfeed_enable)(bool enable);
+    void (*dsp_set_crossfeed_type)(int type);
     void (*dsp_eq_enable)(bool enable);
     void (*dsp_dither_enable)(bool enable);
 #ifdef HAVE_PITCHCONTROL
diff --git a/apps/plugins/mpegplayer/mpeg_settings.c b/apps/plugins/mpegplayer/mpeg_settings.c
index 7f92fb7c69..bcef4c66bf 100644
--- a/apps/plugins/mpegplayer/mpeg_settings.c
+++ b/apps/plugins/mpegplayer/mpeg_settings.c
@@ -457,8 +457,9 @@ static void sync_audio_setting(int setting, bool global)
         break;
 
     case MPEG_AUDIO_CROSSFEED:
-        rb->dsp_crossfeed_enable((global || settings.crossfeed) ?
-                                 rb->global_settings->crossfeed : false);
+        rb->dsp_set_crossfeed_type((global || settings.crossfeed) ?
+                                   rb->global_settings->crossfeed :
+                                   CROSSFEED_TYPE_NONE);
         break;
 
     case MPEG_AUDIO_EQUALIZER:
diff --git a/apps/settings.c b/apps/settings.c
index d777eb1565..3bf9c5bf17 100644
--- a/apps/settings.c
+++ b/apps/settings.c
@@ -979,7 +979,7 @@ void settings_apply(bool read_disk)
     audio_set_crossfade(global_settings.crossfade);
 #endif
     replaygain_update();
-    dsp_crossfeed_enable(global_settings.crossfeed);
+    dsp_set_crossfeed_type(global_settings.crossfeed);
     dsp_set_crossfeed_direct_gain(global_settings.crossfeed_direct_gain);
     dsp_set_crossfeed_cross_params(global_settings.crossfeed_cross_gain,
                                    global_settings.crossfeed_hf_attenuation,
diff --git a/apps/settings.h b/apps/settings.h
index 55d3344cb2..ef0bae520e 100644
--- a/apps/settings.h
+++ b/apps/settings.h
@@ -325,7 +325,7 @@ struct user_settings
     struct replaygain_settings replaygain_settings;
 
     /* Crossfeed */
-    bool crossfeed;                             /* enable crossfeed */
+    int crossfeed;                              /* crossfeed type */
     unsigned int crossfeed_direct_gain;         /* dB x 10 */
     unsigned int crossfeed_cross_gain;          /* dB x 10 */
     unsigned int crossfeed_hf_attenuation;      /* dB x 10 */
diff --git a/apps/settings_list.c b/apps/settings_list.c
index 10d00d5c89..accd51dfe1 100644
--- a/apps/settings_list.c
+++ b/apps/settings_list.c
@@ -1402,8 +1402,10 @@ const struct settings_list settings[] = {
 #endif
 
     /* crossfeed */
-    OFFON_SETTING(F_SOUNDSETTING, crossfeed, LANG_CROSSFEED, false,
-                  "crossfeed", dsp_crossfeed_enable),
+    CHOICE_SETTING(F_SOUNDSETTING, crossfeed, LANG_CROSSFEED, 0,"crossfeed",
+                   "off,meier,custom", dsp_set_crossfeed_type, 3,
+                   ID2P(LANG_OFF), ID2P(LANG_CROSSFEED_MEIER),
+                   ID2P(LANG_CROSSFEED_CUSTOM)),
     INT_SETTING_NOWRAP(F_SOUNDSETTING, crossfeed_direct_gain,
                        LANG_CROSSFEED_DIRECT_GAIN, -15,
                        "crossfeed direct gain", UNIT_DB, -60, 0, 5,
diff --git a/lib/rbcodec/dsp/crossfeed.c b/lib/rbcodec/dsp/crossfeed.c
index 344addadd7..3fb51a7594 100644
--- a/lib/rbcodec/dsp/crossfeed.c
+++ b/lib/rbcodec/dsp/crossfeed.c
@@ -8,6 +8,7 @@
  * $Id$
  *
  * Copyright (C) 2006 Thom Johansen
+ * Copyright (C) 2010 Bertrik Sikken
  * Copyright (C) 2012 Michael Sevakis
  *
  * This program is free software; you can redistribute it and/or
@@ -31,7 +32,11 @@
 #include <string.h>
 
 /* Implemented here or in target assembly code */
-void crossfeed_process(struct dsp_proc_entry *this, struct dsp_buffer **buf_p);
+void crossfeed_process(struct dsp_proc_entry *this,
+                       struct dsp_buffer **buf_p);
+void crossfeed_meier_process(struct dsp_proc_entry *this,
+                             struct dsp_buffer **buf_p);
+
 
 /**
  * Applies crossfeed to the stereo signal.
@@ -46,20 +51,44 @@ static struct crossfeed_state
 {
     int32_t gain;           /* 00h: Direct path gain */
     int32_t coefs[3];       /* 04h: Coefficients for the shelving filter */
-    int32_t history[4];     /* 10h: Format is x[n - 1], y[n - 1] (L + R) */
-    int32_t delay[13*2];    /* 20h: Delay line buffer (L + R interleaved) */
+    union
+    {
+        struct              /* 10h: Data for meier crossfeed */
+        {
+            int32_t vcl;
+            int32_t vcr;
+            int32_t vdiff;
+            int32_t coef1;
+            int32_t coef2;
+        };
+        struct              /* 10h: Data for custom crossfeed */
+        {
+            int32_t history[4]; /* 10h: Format is x[n - 1], y[n - 1] (L + R) */
+            int32_t delay[13*2];/* 20h: Delay line buffer (L + R interleaved) */
+        };
+    };
     int32_t *index;         /* 88h: Current pointer into the delay line */
     struct dsp_config *dsp; /* 8ch: Current DSP */
                             /* 90h */
 } crossfeed_state IBSS_ATTR;
 
+static int crossfeed_type = CROSSFEED_TYPE_NONE;
+
 /* Discard the sample histories */
 static void crossfeed_flush(struct dsp_proc_entry *this)
 {
     struct crossfeed_state *state = (void *)this->data;
-    memset(state->history, 0, sizeof (state->history));
-    memset(state->delay, 0, sizeof (state->delay));
-    state->index = state->delay;
+
+    if (crossfeed_type == CROSSFEED_TYPE_CUSTOM)
+    {
+        memset(state->history, 0,
+            sizeof (state->history) + sizeof (state->delay));
+        state->index = state->delay;
+    }
+    else
+    {
+        state->vcl = state->vcr = state->vdiff = 0;
+    }
 }
 
 
@@ -74,30 +103,48 @@ static void crossfeed_process_new_format(struct dsp_proc_entry *this,
 
     DSP_PRINT_FORMAT(DSP_PROC_CROSSFEED, DSP_PROC_CROSSFEED, buf->format);
 
+    bool was_active = dsp_proc_active(state->dsp, DSP_PROC_CROSSFEED);
     bool active = buf->format.num_channels >= 2;
     dsp_proc_activate(state->dsp, DSP_PROC_CROSSFEED, active);
 
     if (!active)
     {
         /* Can't do this. Sleep until next change */
-        crossfeed_flush(this);
         DEBUGF("  DSP_PROC_CROSSFEED- deactivated\n");
         return;
     }
 
-    /* Switch to the real function and call it once */
-    this->process[0] = crossfeed_process;
+    dsp_proc_fn_type fn = crossfeed_process;
+
+    if (crossfeed_type != CROSSFEED_TYPE_CUSTOM)
+    {
+        /* 1 / (F.Rforward.C) */
+        state->coef1 = (0x7fffffff / NATIVE_FREQUENCY) * 2128;
+        /* 1 / (F.Rcross.C) */
+        state->coef2 = (0x7fffffff / NATIVE_FREQUENCY) * 1000;
+        fn = crossfeed_meier_process;
+    }
+
+    if (!was_active || this->process[0] != fn)
+    {
+        crossfeed_flush(this); /* Going online or actual type change */
+        this->process[0] = fn; /* Set real function */
+    }
+
+    /* Call it once */
     dsp_proc_call(this, buf_p, (unsigned)buf->format.changed - 1);
 }
 
-/* Enable or disable the crossfeed */
-void dsp_crossfeed_enable(bool enable)
+/* Set the type of crossfeed to use */
+void dsp_set_crossfeed_type(int type)
 {
-    if (enable != !crossfeed_state.dsp)
-        return;
+    if (type == crossfeed_type)
+        return; /* No change */
+
+    crossfeed_type = type;
 
     struct dsp_config *dsp = dsp_get_config(CODEC_IDX_AUDIO);
-    dsp_proc_enable(dsp, DSP_PROC_CROSSFEED, enable);
+    dsp_proc_enable(dsp, DSP_PROC_CROSSFEED, type != CROSSFEED_TYPE_NONE);
 }
 
 /* Set the gain of the dry mix */
@@ -182,6 +229,50 @@ void crossfeed_process(struct dsp_proc_entry *this, struct dsp_buffer **buf_p)
 }
 #endif /* CPU */
 
+#if !defined(CPU_COLDFIRE) && !defined(CPU_ARM)
+/**
+ * Implementation of the "simple" passive crossfeed circuit by Jan Meier.
+ * See also: http://www.meier-audio.homepage.t-online.de/passivefilter.htm
+ */
+
+void crossfeed_meier_process(struct dsp_proc_entry *this,
+                             struct dsp_buffer **buf_p)
+{
+    struct dsp_buffer *buf = *buf_p;
+
+    /* Get filter state */
+    struct crossfeed_state *state = (struct crossfeed_state *)this->data;
+    int32_t vcl = state->vcl;
+    int32_t vcr = state->vcr;
+    int32_t vdiff = state->vdiff;
+    int32_t coef1 = state->coef1;
+    int32_t coef2 = state->coef2;
+
+    int count = buf->remcount;
+
+    for (int i = 0; i < count; i++)
+    {
+        /* Calculate new output */
+        int32_t lout = buf->p32[0][i] + vcl;
+        int32_t rout = buf->p32[1][i] + vcr;
+        buf->p32[0][i] = lout;
+        buf->p32[1][i] = rout;
+
+        /* Update filter state */
+        int32_t common = FRACMUL(vdiff, coef2);
+        vcl -= FRACMUL(vcl, coef1) + common;
+        vcr -= FRACMUL(vcr, coef1) - common;
+
+        vdiff = lout - rout;
+    }
+
+    /* Store filter state */
+    state->vcl = vcl;
+    state->vcr = vcr;
+    state->vdiff = vdiff;
+}
+#endif /* CPU */
+
 /* DSP message hook */
 static intptr_t crossfeed_configure(struct dsp_proc_entry *this,
                                     struct dsp_config *dsp,
@@ -191,11 +282,19 @@ static intptr_t crossfeed_configure(struct dsp_proc_entry *this,
     switch (setting)
     {
     case DSP_PROC_INIT:
-        this->data = (intptr_t)&crossfeed_state;
+        if (value == 0)
+        {
+            /* New object */
+            this->data = (intptr_t)&crossfeed_state;
+            this->process[1] = crossfeed_process_new_format;
+            ((struct crossfeed_state *)this->data)->dsp = dsp;
+        }
+
+        /* Force format change call each time */
         this->process[0] = crossfeed_process_new_format;
-        this->process[1] = crossfeed_process_new_format;
-        ((struct crossfeed_state *)this->data)->dsp = dsp;
         dsp_proc_activate(dsp, DSP_PROC_CROSSFEED, true);
+        break;
+
     case DSP_FLUSH:
         crossfeed_flush(this);
         break;
diff --git a/lib/rbcodec/dsp/crossfeed.h b/lib/rbcodec/dsp/crossfeed.h
index 63261bde9f..2c4d47dba5 100644
--- a/lib/rbcodec/dsp/crossfeed.h
+++ b/lib/rbcodec/dsp/crossfeed.h
@@ -21,7 +21,14 @@
 #ifndef CROSSFEED_H
 #define CROSSFEED_H
 
-void dsp_crossfeed_enable(bool enable);
+enum crossfeed_type
+{
+    CROSSFEED_TYPE_NONE,
+    CROSSFEED_TYPE_MEIER,
+    CROSSFEED_TYPE_CUSTOM,
+};
+
+void dsp_set_crossfeed_type(int type);
 void dsp_set_crossfeed_direct_gain(int gain);
 void dsp_set_crossfeed_cross_params(long lf_gain, long hf_gain, long cutoff);
 
diff --git a/lib/rbcodec/dsp/dsp_arm.S b/lib/rbcodec/dsp/dsp_arm.S
index 1674d6617a..4fdaf8d5a8 100644
--- a/lib/rbcodec/dsp/dsp_arm.S
+++ b/lib/rbcodec/dsp/dsp_arm.S
@@ -8,6 +8,8 @@
  * $Id$
  *
  * Copyright (C) 2006-2007 Thom Johansen
+ * Copyright (C) 2010 Bertrik Sikken
+ * Copyright (C) 2012 Michael Sevakis
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -247,6 +249,48 @@ crossfeed_process:
     .size   crossfeed_process, .-crossfeed_process
 
 /****************************************************************************
+ * void crossfeed_meier_process(struct dsp_proc_entry *this,
+ *                              struct dsp_buffer **buf_p)
+ */
+    .section .text
+    .global crossfeed_meier_process
+crossfeed_meier_process:
+    @ input: r0 = this, r1 = buf_p
+    ldr     r1, [r1]                   @ r1 = buf = *buf_p;
+    ldr     r0, [r0]                   @ r0 = this->data = &crossfeed_state
+    stmfd   sp!, { r4-r10, lr }        @ stack non-volatile context
+    ldmia   r1, { r1-r3 }              @ r1 = buf->remcout, r2=p32[0], r3=p32[1]
+    add     r0, r0, #16                @ r0 = &state->vcl
+    ldmia   r0, { r4-r8 }              @ r4 = vcl, r5 = vcr, r6 = vdiff
+                                       @ r7 = coef1, r8 = coef2
+.cfm_loop:
+    ldr     r12, [r2]                  @ r12 = lout
+    ldr     r14, [r3]                  @ r14 = rout
+    smull   r9, r10, r8, r6            @ r9, r10  = common = coef2*vdiff
+    add     r12, r12, r4               @ lout += vcl
+    add     r14, r14, r5               @ rout += vcr
+    sub     r6, r12, r14               @ r6 = vdiff = lout - rout
+    str     r12, [r2], #4              @ store left channel
+    str     r14, [r3], #4              @ store right channel
+    rsbs    r12, r9, #0                @ r12 = -common (lo)
+    rsc     r14, r10, #0               @ r14 = -common (hi)
+    smlal   r9, r10, r7, r4            @ r9, r10  = res1 = coef1*vcl + common
+    smlal   r12, r14, r7, r5           @ r12, r14 = res2 = coef1*vcr - common
+    subs    r1, r1, #1                 @ count--
+    mov     r9, r9, lsr #31            @ r9 = convert res1 to s0.31
+    orr     r9, r9, r10, asl #1        @ .
+    mov     r12, r12, lsr #31          @ r12 = convert res2 to s0.31
+    orr     r12, r12, r14, asl #1      @ .
+    sub     r4, r4, r9                 @ r4 = vcl -= res1
+    sub     r5, r5, r12                @ r5 = vcr -= res2
+    bgt     .cfm_loop                  @ more samples?
+
+    stmia   r0, { r4-r6 }              @ save vcl, vcr, vdiff
+    ldmpc   regs=r4-r10                @ restore non-volatile context, return
+    .size   crossfeed_meier_process, .-crossfeed_meier_process
+
+
+/****************************************************************************
  * int lin_resample_resample(struct resample_data *data,
  *                           struct dsp_buffer *src,
  *                           struct dsp_buffer *dst)
diff --git a/lib/rbcodec/dsp/dsp_cf.S b/lib/rbcodec/dsp/dsp_cf.S
index c710df5177..7d193e0957 100644
--- a/lib/rbcodec/dsp/dsp_cf.S
+++ b/lib/rbcodec/dsp/dsp_cf.S
@@ -8,7 +8,8 @@
  * $Id$
  *
  * Copyright (C) 2006 Thom Johansen
- * Portions Copyright (C) 2007 Michael Sevakis
+ * Copyright (C) 2007, 2012 Michael Sevakis
+ * Copyright (C) 2010 Bertrik Sikken
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -134,6 +135,50 @@ crossfeed_process:
     .size       crossfeed_process,.-crossfeed_process
 
 /****************************************************************************
+ * void crossfeed_meier_process(struct dsp_proc_entry *this,
+ *                              struct dsp_buffer **buf_p)
+ */
+    .section .text
+    .global crossfeed_meier_process
+crossfeed_meier_process:
+    | input: 4(sp) = this, 8(sp) = buf_p
+    movem.l     4(%sp), %a0-%a1         | %a0 = this, %a1 = buf_p
+    lea.l       -24(%sp), %sp           | save non-volatiles
+    movem.l     %d2-%d6/%a2, (%sp)      | .
+    move.l      (%a0), %a0              | %a0 = &this->data = &crossfeed_state
+    move.l      (%a1), %a1              | %a1 = buf = *buf_p
+    movem.l     16(%a0), %d1-%d5        | %d1 = vcl, %d2 = vcr, %d3 = vdiff,
+                                        | %d4 = coef1, %d5 = coef2
+    movem.l     (%a1), %d0/%a1-%a2      | %d0 = count = buf->remcount
+                                        | %a1 = p32[0], %a2 = p32[1]
+    | Register usage in loop:
+    | %d0 = count, %d1 = vcl, %d2 = vcr, %d3 = vdiff/lout,
+    | %d4 = coef1, %d5 = coef2, %d6 = rout/scratch
+    | %a1 = p32[0], %a2 = p32[1]
+10: | loop
+    mac.l       %d5, %d3, %acc0         | %acc0 = common = coef2*vdiff
+    move.l      %acc0, %acc1            | copy common
+    mac.l       %d4, %d1, (%a1), %d3, %acc0 | %acc0 += coef1*vcl, %d3 = lout
+    msac.l      %d4, %d2, (%a2), %d6, %acc1 | %acc1 -= coef1*vcr, %d6 = rout
+    add.l       %d1, %d3                | lout += vcl
+    add.l       %d2, %d6                | rout += vcr
+    move.l      %d3, (%a1)+             | store left channel, pos inc
+    move.l      %d6, (%a2)+             | store right channel, pos inc
+    sub.l       %d6, %d3                | vdiff = lout - rout
+    movclr.l    %acc0, %d6              | %d4 = fetch res1 in s0.31
+    sub.l       %d6, %d1                | vcl -= res1
+    movclr.l    %acc1, %d6              | %d5 = fetch -res2 in s0.31
+    add.l       %d6, %d2                | vcr += -res2
+    subq.l      #1, %d0                 | count--
+    bgt         10b | loop              | more samples?
+                                        |
+    movem.l     %d1-%d3, 16(%a0)        | save vcl, vcr, vdiff
+    movem.l     (%sp), %d2-%d6/%a2      | restore non-volatiles
+    lea.l       24(%sp), %sp            | .
+    rts                                 |
+    .size   crossfeed_meier_process, .-crossfeed_meier_process
+
+/****************************************************************************
  * int lin_resample_resample(struct resample_data *data,
  *                           struct dsp_buffer *src,
  *                           struct dsp_buffer *dst)