1 files changed, 35 insertions, 10 deletions

diff --git a/sound/usb/clock.c b/sound/usb/clock.c
index 5e634a2eb282..9e2703a25156 100644
--- a/sound/usb/clock.c
+++ b/sound/usb/clock.c
@@ -253,7 +253,7 @@ static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
 {
         struct usb_device *dev = chip->dev;
         unsigned char data[4];
-        int err, crate;
+        int err, cur_rate, prev_rate;
         int clock = snd_usb_clock_find_source(chip, fmt->clock);
 
         if (clock < 0)
@@ -266,6 +266,19 @@ static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
                 return -ENXIO;
         }
 
+        err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
+                              USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
+                              UAC2_CS_CONTROL_SAM_FREQ << 8,
+                              snd_usb_ctrl_intf(chip) | (clock << 8),
+                              data, sizeof(data));
+        if (err < 0) {
+                snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq (v2)\n",
+                           dev->devnum, iface, fmt->altsetting);
+                prev_rate = 0;
+        } else {
+                prev_rate = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
+        }
+
         data[0] = rate;
         data[1] = rate >> 8;
         data[2] = rate >> 16;
@@ -280,19 +293,31 @@ static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
                 return err;
         }
 
-        if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
-                                   USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
-                                   UAC2_CS_CONTROL_SAM_FREQ << 8,
-                                   snd_usb_ctrl_intf(chip) | (clock << 8),
-                                   data, sizeof(data))) < 0) {
+        err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
+                              USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
+                              UAC2_CS_CONTROL_SAM_FREQ << 8,
+                              snd_usb_ctrl_intf(chip) | (clock << 8),
+                              data, sizeof(data));
+        if (err < 0) {
                 snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq (v2)\n",
                            dev->devnum, iface, fmt->altsetting);
-                return err;
+                cur_rate = 0;
+        } else {
+                cur_rate = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
         }
 
-        crate = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
-        if (crate != rate)
-                snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", crate, rate);
+        if (cur_rate != rate) {
+                snd_printd(KERN_WARNING
+                           "current rate %d is different from the runtime rate %d\n",
+                           cur_rate, rate);
+        }
+
+        /* Some devices doesn't respond to sample rate changes while the
+         * interface is active. */
+        if (rate != prev_rate) {
+                usb_set_interface(dev, iface, 0);
+                usb_set_interface(dev, iface, fmt->altsetting);
+        }
 
         return 0;
 }