ALSA: usb-audio: Use rwsem for disconnect protection

[pandora-kernel.git] / sound / usb / mixer.c

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index fe56c9d..298070e 100644 (file)
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -287,25 +287,32 @@ static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int v
        unsigned char buf[2];
        int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
        int timeout = 10;
-       int err;
+       int idx = 0, err;
 
        err = snd_usb_autoresume(cval->mixer->chip);
        if (err < 0)
                return -EIO;
+       down_read(&chip->shutdown_rwsem);
        while (timeout-- > 0) {
+               if (chip->shutdown)
+                       break;
+               idx = snd_usb_ctrl_intf(chip) | (cval->id << 8);
                if (snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
                                    USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
-                                   validx, snd_usb_ctrl_intf(chip) | (cval->id << 8),
-                                   buf, val_len) >= val_len) {
+                                   validx, idx, buf, val_len) >= val_len) {
                        *value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
-                       snd_usb_autosuspend(cval->mixer->chip);
-                       return 0;
+                       err = 0;
+                       goto out;
                }
        }
-       snd_usb_autosuspend(cval->mixer->chip);
        snd_printdd(KERN_ERR "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
-                   request, validx, snd_usb_ctrl_intf(chip) | (cval->id << 8), cval->val_type);
-       return -EINVAL;
+                   request, validx, idx, cval->val_type);
+       err = -EINVAL;
+
+ out:
+       up_read(&chip->shutdown_rwsem);
+       snd_usb_autosuspend(cval->mixer->chip);
+       return err;
 }
 
 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret)
@@ -313,7 +320,7 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v
        struct snd_usb_audio *chip = cval->mixer->chip;
        unsigned char buf[2 + 3*sizeof(__u16)]; /* enough space for one range */
        unsigned char *val;
-       int ret, size;
+       int idx = 0, ret, size;
        __u8 bRequest;
 
        if (request == UAC_GET_CUR) {
@@ -330,16 +337,22 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v
        if (ret)
                goto error;
 
-       ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
+       down_read(&chip->shutdown_rwsem);
+       if (chip->shutdown)
+               ret = -ENODEV;
+       else {
+               idx = snd_usb_ctrl_intf(chip) | (cval->id << 8);
+               ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
                              USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
-                             validx, snd_usb_ctrl_intf(chip) | (cval->id << 8),
-                             buf, size);
+                             validx, idx, buf, size);
+       }
+       up_read(&chip->shutdown_rwsem);
        snd_usb_autosuspend(chip);
 
        if (ret < 0) {
 error:
                snd_printk(KERN_ERR "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
-                          request, validx, snd_usb_ctrl_intf(chip) | (cval->id << 8), cval->val_type);
+                          request, validx, idx, cval->val_type);
                return ret;
        }
 
@@ -417,7 +430,7 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
 {
        struct snd_usb_audio *chip = cval->mixer->chip;
        unsigned char buf[2];
-       int val_len, err, timeout = 10;
+       int idx = 0, val_len, err, timeout = 10;
 
        if (cval->mixer->protocol == UAC_VERSION_1) {
                val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
@@ -440,19 +453,27 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
        err = snd_usb_autoresume(chip);
        if (err < 0)
                return -EIO;
-       while (timeout-- > 0)
+       down_read(&chip->shutdown_rwsem);
+       while (timeout-- > 0) {
+               if (chip->shutdown)
+                       break;
+               idx = snd_usb_ctrl_intf(chip) | (cval->id << 8);
                if (snd_usb_ctl_msg(chip->dev,
                                    usb_sndctrlpipe(chip->dev, 0), request,
                                    USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
-                                   validx, snd_usb_ctrl_intf(chip) | (cval->id << 8),
-                                   buf, val_len) >= 0) {
-                       snd_usb_autosuspend(chip);
-                       return 0;
+                                   validx, idx, buf, val_len) >= 0) {
+                       err = 0;
+                       goto out;
                }
-       snd_usb_autosuspend(chip);
+       }
        snd_printdd(KERN_ERR "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
-                   request, validx, snd_usb_ctrl_intf(chip) | (cval->id << 8), cval->val_type, buf[0], buf[1]);
-       return -EINVAL;
+                   request, validx, idx, cval->val_type, buf[0], buf[1]);
+       err = -EINVAL;
+
+ out:
+       up_read(&chip->shutdown_rwsem);
+       snd_usb_autosuspend(chip);
+       return err;
 }
 
 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval, int validx, int value)