svn commit: r282017 - head/sys/dev/sound/pcm

[Hans Petter Selasky]

Author: hselasky
Date: Sun Apr 26 11:39:13 2015
New Revision: 282017
URL: https://svnweb.freebsd.org/changeset/base/282017

Log:
  Allow DSP basename cloning to be disabled or enabled at boot and
  runtime. This is useful when implementing OSS sound stacks in
  userspace via libcuse for example.
  
  MFC after:	2 weeks

Modified:
  head/sys/dev/sound/pcm/dsp.c

Modified: head/sys/dev/sound/pcm/dsp.c
==============================================================================
--- head/sys/dev/sound/pcm/dsp.c	Sun Apr 26 11:35:36 2015	(r282016)
+++ head/sys/dev/sound/pcm/dsp.c	Sun Apr 26 11:39:13 2015	(r282017)
@@ -48,6 +48,11 @@ SYSCTL_INT(_hw_snd, OID_AUTO, compat_lin
     &dsp_mmap_allow_prot_exec, 0,
     "linux mmap compatibility (-1=force disable 0=auto 1=force enable)");
 
+static int dsp_basename_clone = 1;
+SYSCTL_INT(_hw_snd, OID_AUTO, basename_clone, CTLFLAG_RWTUN,
+    &dsp_basename_clone, 0,
+    "DSP basename cloning (0: Disable; 1: Enabled)");
+
 struct dsp_cdevinfo {
 	struct pcm_channel *rdch, *wrch;
 	struct pcm_channel *volch;
@@ -2357,9 +2362,10 @@ dsp_clone(void *arg,
 			devname = devcmp;
 		devhw = dsp_cdevs[i].hw;
 		devcmax = dsp_cdevs[i].max - 1;
-		if (strcmp(name, devcmp) == 0)
-			unit = snd_unit;
-		else if (dsp_stdclone(name, devcmp, devsep,
+		if (strcmp(name, devcmp) == 0) {
+			if (dsp_basename_clone != 0)
+				unit = snd_unit;
+		} else if (dsp_stdclone(name, devcmp, devsep,
 		    dsp_cdevs[i].use_sep, &unit, &cunit) != 0) {
 			unit = -1;
 			cunit = -1;