On Fri, 7 Oct 2016 14:24:21 -0300
Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> wrote:
> 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.
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/usb/dvb-usb/digitv.c | 20 +++++++++++---------
> drivers/media/usb/dvb-usb/digitv.h | 3 +++
> 2 files changed, 14 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/media/usb/dvb-usb/digitv.c
> b/drivers/media/usb/dvb-usb/digitv.c index 63134335c994..09f8c28bd4db
> 100644 --- 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 908c09f4966b..cf104689bdff
> 100644 --- a/drivers/media/usb/dvb-usb/digitv.h
> +++ b/drivers/media/usb/dvb-usb/digitv.h
> @@ -6,6 +6,9 @@
>
> struct digitv_state {
> int is_nxt6000;
> +
> + unsigned char sndbuf[7];
> + unsigned char rcvbuf[7];
> };
>
> /* protocol (from usblogging and the SDK:
Reviewed-By: Patrick Boettcher <patrick.boettcher@xxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
