ALSA: 6fire: make buffers DMA-able (pcm)

Patch makes pcm buffers DMA-able by allocating each one separately.

Signed-off-by: Torsten Schenk <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Takashi Iwai <[e-mail]>

sound/usb/6fire/pcm.c

···
 	urb->instance.number_of_packets = PCM_N_PACKETS_PER_URB;
 }
 
+static int usb6fire_pcm_buffers_init(struct pcm_runtime *rt)
+{
+	int i;
+
+	for (i = 0; i < PCM_N_URBS; i++) {
+		rt->out_urbs[i].buffer = kzalloc(PCM_N_PACKETS_PER_URB
+				* PCM_MAX_PACKET_SIZE, GFP_KERNEL);
+		if (!rt->out_urbs[i].buffer)
+			return -ENOMEM;
+		rt->in_urbs[i].buffer = kzalloc(PCM_N_PACKETS_PER_URB
+				* PCM_MAX_PACKET_SIZE, GFP_KERNEL);
+		if (!rt->in_urbs[i].buffer)
+			return -ENOMEM;
+	}
+	return 0;
+}
+
+static void usb6fire_pcm_buffers_destroy(struct pcm_runtime *rt)
+{
+	int i;
+
+	for (i = 0; i < PCM_N_URBS; i++) {
+		kfree(rt->out_urbs[i].buffer);
+		kfree(rt->in_urbs[i].buffer);
+	}
+}
+
 int usb6fire_pcm_init(struct sfire_chip *chip)
 {
 	int i;
···
 
 	if (!rt)
 		return -ENOMEM;
+
+	ret = usb6fire_pcm_buffers_init(rt);
+	if (ret) {
+		usb6fire_pcm_buffers_destroy(rt);
+		kfree(rt);
+		return ret;
+	}
 
 	rt->chip = chip;
 	rt->stream_state = STREAM_DISABLED;
···
 
 	ret = snd_pcm_new(chip->card, "DMX6FireUSB", 0, 1, 1, &pcm);
 	if (ret < 0) {
+		usb6fire_pcm_buffers_destroy(rt);
 		kfree(rt);
 		snd_printk(KERN_ERR PREFIX "cannot create pcm instance.\n");
 		return ret;
···
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &pcm_ops);
 
 	if (ret) {
+		usb6fire_pcm_buffers_destroy(rt);
 		kfree(rt);
 		snd_printk(KERN_ERR PREFIX
 				"error preallocating pcm buffers.\n");
···
 
 void usb6fire_pcm_destroy(struct sfire_chip *chip)
 {
-	kfree(chip->pcm);
+	struct pcm_runtime *rt = chip->pcm;
+
+	usb6fire_pcm_buffers_destroy(rt);
+	kfree(rt);
 	chip->pcm = NULL;
 }

sound/usb/6fire/pcm.h

···
 	struct urb instance;
 	struct usb_iso_packet_descriptor packets[PCM_N_PACKETS_PER_URB];
 	/* END DO NOT SEPARATE */
-	u8 buffer[PCM_N_PACKETS_PER_URB * PCM_MAX_PACKET_SIZE];
+	u8 *buffer;
 
 	struct pcm_urb *peer;
 };