3 files changed, 6 insertions, 0 deletions

diff --git a/drivers/isdn/mISDN/dsp.h b/drivers/isdn/mISDN/dsp.h
index 564ea3efd5e3..18af86879c05 100644
--- a/drivers/isdn/mISDN/dsp.h
+++ b/drivers/isdn/mISDN/dsp.h
@@ -116,6 +116,7 @@ struct dsp_conf {
 #define ECHOCAN_BUFF_MASK 0x3ff /* -1 */
 
 struct dsp_dtmf {
+        int             enable; /* dtmf is enabled */
         int             treshold; /* above this is dtmf (square of) */
         int             software; /* dtmf uses software decoding */
         int             hardware; /* dtmf uses hardware decoding */
diff --git a/drivers/isdn/mISDN/dsp_core.c b/drivers/isdn/mISDN/dsp_core.c
index c35750647c66..c12cd2f94254 100644
--- a/drivers/isdn/mISDN/dsp_core.c
+++ b/drivers/isdn/mISDN/dsp_core.c
@@ -306,6 +306,7 @@ dsp_control_req(struct dsp *dsp, struct mISDNhead *hh, struct sk_buff *skb)
                                         "to %d\n", *((int *)data));
                         dsp->dtmf.treshold = (*(int *)data) * 10000;
                 }
+                dsp->dtmf.enable = 1;
                 /* init goertzel */
                 dsp_dtmf_goertzel_init(dsp);
 
@@ -316,6 +317,7 @@ dsp_control_req(struct dsp *dsp, struct mISDNhead *hh, struct sk_buff *skb)
         case DTMF_TONE_STOP: /* turn off DTMF */
                 if (dsp_debug & DEBUG_DSP_CORE)
                         printk(KERN_DEBUG "%s: stop dtmf\n", __func__);
+                dsp->dtmf.enable = 0;
                 dsp->dtmf.hardware = 0;
                 dsp->dtmf.software = 0;
                 break;
diff --git a/drivers/isdn/mISDN/dsp_dtmf.c b/drivers/isdn/mISDN/dsp_dtmf.c
index efc371c1f0dc..9ae2d33b06f7 100644
--- a/drivers/isdn/mISDN/dsp_dtmf.c
+++ b/drivers/isdn/mISDN/dsp_dtmf.c
@@ -51,6 +51,9 @@ void dsp_dtmf_hardware(struct dsp *dsp)
 {
         int hardware = 1;
 
+        if (!dsp->dtmf.enable)
+                return;
+
         if (!dsp->features.hfc_dtmf)
                 hardware = 0;