[media] digitv: 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/digitv.c b/drivers/media/usb/dvb-usb/digitv.c
index 63134335c99406ca7df3d284cd3ba95d4154cae3..09f8c28bd4db902a81bf61d1dc6ac9ea5ab93665 100644 (file)
--- a/drivers/media/usb/dvb-usb/digitv.c
+++ b/drivers/media/usb/dvb-usb/digitv.c
@@ -28,20 +28,22 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
 static int digitv_ctrl_msg(struct dvb_usb_device *d,
                u8 cmd, u8 vv, u8 *wbuf, int wlen, u8 *rbuf, int rlen)
 {
+       struct digitv_state *st = d->priv;
        int wo = (rbuf == NULL || rlen == 0); /* write-only */
-       u8 sndbuf[7],rcvbuf[7];
-       memset(sndbuf,0,7); memset(rcvbuf,0,7);
 
-       sndbuf[0] = cmd;
-       sndbuf[1] = vv;
-       sndbuf[2] = wo ? wlen : rlen;
+       memset(st->sndbuf, 0, 7);
+       memset(st->rcvbuf, 0, 7);
+
+       st->sndbuf[0] = cmd;
+       st->sndbuf[1] = vv;
+       st->sndbuf[2] = wo ? wlen : rlen;
 
        if (wo) {
-               memcpy(&sndbuf[3],wbuf,wlen);
-               dvb_usb_generic_write(d,sndbuf,7);
+               memcpy(&st->sndbuf[3], wbuf, wlen);
+               dvb_usb_generic_write(d, st->sndbuf, 7);
        } else {
-               dvb_usb_generic_rw(d,sndbuf,7,rcvbuf,7,10);
-               memcpy(rbuf,&rcvbuf[3],rlen);
+               dvb_usb_generic_rw(d, st->sndbuf, 7, st->rcvbuf, 7, 10);
+               memcpy(rbuf, &st->rcvbuf[3], rlen);
        }
        return 0;
 }

diff --git a/drivers/media/usb/dvb-usb/digitv.h b/drivers/media/usb/dvb-usb/digitv.h
index 908c09f4966b89b8923569b35a5a2cbc3b8a6727..581e09c25491bfe54a683fbfd094a890c0351c4a 100644 (file)
--- a/drivers/media/usb/dvb-usb/digitv.h
+++ b/drivers/media/usb/dvb-usb/digitv.h
@@ -5,7 +5,10 @@
 #include "dvb-usb.h"
 
 struct digitv_state {
-    int is_nxt6000;
+       int is_nxt6000;
+
+       unsigned char sndbuf[7];
+       unsigned char rcvbuf[7];
 };
 
 /* protocol (from usblogging and the SDK: