[media] nova-t-usb2: don't do DMA on stack

The USB control messages require DMA to work. We cannot pass
a stack-allocated buffer, as it is not warranted that the
stack would be into a DMA enabled area.

Reviewed-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/usb/dvb-usb/nova-t-usb2.c b/drivers/media/usb/dvb-usb/nova-t-usb2.c
index fc7569e..26d7188 100644 (file)
--- a/drivers/media/usb/dvb-usb/nova-t-usb2.c
+++ b/drivers/media/usb/dvb-usb/nova-t-usb2.c
@@ -74,22 +74,29 @@ static struct rc_map_table rc_map_haupp_table[] = {
  */
 static int nova_t_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
 {
-       u8 key[5],cmd[2] = { DIBUSB_REQ_POLL_REMOTE, 0x35 }, data,toggle,custom;
+       u8 *buf, data, toggle, custom;
        u16 raw;
        int i;
        struct dibusb_device_state *st = d->priv;
 
-       dvb_usb_generic_rw(d,cmd,2,key,5,0);
+       buf = kmalloc(5, GFP_KERNEL);
+       if (!buf)
+               return -ENOMEM;
+
+       buf[0] = DIBUSB_REQ_POLL_REMOTE;
+       buf[1] = 0x35;
+       dvb_usb_generic_rw(d, buf, 2, buf, 5, 0);
 
        *state = REMOTE_NO_KEY_PRESSED;
-       switch (key[0]) {
+       switch (buf[0]) {
                case DIBUSB_RC_HAUPPAUGE_KEY_PRESSED:
-                       raw = ((key[1] << 8) | key[2]) >> 3;
+                       raw = ((buf[1] << 8) | buf[2]) >> 3;
                        toggle = !!(raw & 0x800);
                        data = raw & 0x3f;
                        custom = (raw >> 6) & 0x1f;
 
-                       deb_rc("raw key code 0x%02x, 0x%02x, 0x%02x to c: %02x d: %02x toggle: %d\n",key[1],key[2],key[3],custom,data,toggle);
+                       deb_rc("raw key code 0x%02x, 0x%02x, 0x%02x to c: %02x d: %02x toggle: %d\n",
+                              buf[1], buf[2], buf[3], custom, data, toggle);
 
                        for (i = 0; i < ARRAY_SIZE(rc_map_haupp_table); i++) {
                                if (rc5_data(&rc_map_haupp_table[i]) == data &&
@@ -117,6 +124,7 @@ static int nova_t_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
                        break;
        }
 
+       kfree(buf);
        return 0;
 }