Use settings for DAC AGC, cpeaker driver bias current (which is unused in rockbox), dither, and headphone bias current taken from c200v2 firmware. These should result in several mA power savings on all as3525, and probably an improvement on AS3525v2 as well as the c200v1 and e200v1. RMAA tests on the e200v1, clipv1 and clipv2 show no measurable difference in output when driving a 16 ohm load.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25821 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 9 insertions, 6 deletions

diff --git a/firmware/drivers/audio/as3514.c b/firmware/drivers/audio/as3514.c
index a3be9e9246..c161cd69d0 100644
--- a/firmware/drivers/audio/as3514.c
+++ b/firmware/drivers/audio/as3514.c
@@ -173,18 +173,21 @@ void audiohw_preinit(void)
     /* Turn on SUM, DAC */
     as3514_write(AS3514_AUDIOSET1, AUDIOSET1_DAC_on | AUDIOSET1_SUM_on);
 
-    /* Set BIAS on, DITH on, AGC on, IBR_DAC max, LSP_LP on, IBR_LSP min */
-    as3514_write(AS3514_AUDIOSET2,
-                 AUDIOSET2_IBR_DAC_0 | AUDIOSET2_LSP_LP |
-                 AUDIOSET2_IBR_LSP_50);
+    /* Set BIAS on, DITH off, AGC off, IBR_DAC max reduction, LSP_LP on, 
+       IBR_LSP max reduction (50%), taken from c200v2 OF
+     */
+    as3514_write(AS3514_AUDIOSET2, AUDIOSET2_IBR_LSP_50 | AUDIOSET2_LSP_LP |
+            AUDIOSET2_IBR_DAC_50 | AUDIOSET2_AGC_off |AUDIOSET2_DITH_off );
 
 /* AMS Sansas based on the AS3525 need HPCM enabled, otherwise they output the
    L-R signal on both L and R headphone outputs instead of normal stereo.
    Turning it off saves a little power on targets that don't need it. */
 #if (CONFIG_CPU == AS3525)
-    /* Set HPCM on, ZCU on */
-    as3514_write(AS3514_AUDIOSET3, 0);
+    /* Set HPCM on, ZCU off, reduce bias current, settings taken from c200v2 OF
+     */
+    as3514_write(AS3514_AUDIOSET3, AUDIOSET3_IBR_HPH | AUDIOSET3_ZCU_off);
 #else
+    /* TODO: check if AS3525 settings save power on e200v1 or as3525v2 */
     /* Set HPCM off, ZCU on */
     as3514_write(AS3514_AUDIOSET3, AUDIOSET3_HPCM_off);
 #endif