tester wanted: am7930

[Tetsuya Isaki <isaki%pastel-flower.jp@localhost>]

Hi,

I'd like am7930 users to test the following patch.
As a result of recent audio improvement, I think that null_filter
became unnecessary.

Thanks,
---
Tetsuya Isaki <isaki%pastel-flower.jp@localhost / isaki%NetBSD.org@localhost>

RCS file: /cvsroot/src/sys/dev/ic/am7930.c,v
retrieving revision 1.57
diff -u -r1.57 am7930.c
--- sys/dev/ic/am7930.c	29 Aug 2017 06:38:49 -0000	1.57
+++ sys/dev/ic/am7930.c	30 Sep 2017 12:51:00 -0000
@@ -137,8 +137,6 @@
 #define NGER (sizeof(ger_coeff) / sizeof(ger_coeff[0]))
 };
 
-extern stream_filter_factory_t null_filter;
-
 /*
  * Reset chip and set boot-time softc defaults.
  */
@@ -218,9 +216,6 @@
 	DPRINTF(("sa_close: closed.\n"));
 }
 
-/*
- * XXX should be extended to handle a few of the more common formats.
- */
 int
 am7930_set_params(void *addr, int setmode, int usemode, audio_params_t *p,
     audio_params_t *r, stream_filter_list_t *pfil, stream_filter_list_t *rfil)
@@ -240,8 +235,6 @@
 		if (sc->sc_glue->output_conv != NULL) {
 			hw = *p;
 			hw.encoding = AUDIO_ENCODING_NONE;
-			hw.precision = 8;
-			pfil->append(pfil, null_filter, &hw);
 			hw.precision *= sc->sc_glue->factor;
 			pfil->append(pfil, sc->sc_glue->output_conv, &hw);
 		}
@@ -264,8 +257,6 @@
 		if (sc->sc_glue->input_conv != NULL) {
 			hw = *r;
 			hw.encoding = AUDIO_ENCODING_NONE;
-			hw.precision = 8;
-			rfil->append(rfil, null_filter, &hw);
 			hw.precision *= sc->sc_glue->factor;
 			rfil->append(rfil, sc->sc_glue->input_conv, &hw);
 		}