On Fri, 7 Oct 2016 14:24:16 -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/cxusb.c | 20 +++++++-------------
> drivers/media/usb/dvb-usb/cxusb.h | 5 +++++
> 2 files changed, 12 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/media/usb/dvb-usb/cxusb.c
> b/drivers/media/usb/dvb-usb/cxusb.c index 907ac01ae297..f3615349de52
> 100644 --- a/drivers/media/usb/dvb-usb/cxusb.c
> +++ b/drivers/media/usb/dvb-usb/cxusb.c
> @@ -45,9 +45,6 @@
> #include "si2168.h"
> #include "si2157.h"
>
> -/* Max transfer size done by I2C transfer functions */
> -#define MAX_XFER_SIZE 80
> -
> /* debug */
> static int dvb_usb_cxusb_debug;
> module_param_named(debug, dvb_usb_cxusb_debug, int, 0644);
> @@ -61,23 +58,20 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
> static int cxusb_ctrl_msg(struct dvb_usb_device *d,
> u8 cmd, u8 *wbuf, int wlen, u8 *rbuf, int
> rlen) {
> + struct cxusb_state *st = d->priv;
> int wo = (rbuf == NULL || rlen == 0); /* write-only */
> - u8 sndbuf[MAX_XFER_SIZE];
>
> - if (1 + wlen > sizeof(sndbuf)) {
> - warn("i2c wr: len=%d is too big!\n",
> - wlen);
> + if (1 + wlen > MAX_XFER_SIZE) {
> + warn("i2c wr: len=%d is too big!\n", wlen);
> return -EOPNOTSUPP;
> }
>
> - memset(sndbuf, 0, 1+wlen);
> -
> - sndbuf[0] = cmd;
> - memcpy(&sndbuf[1], wbuf, wlen);
> + st->data[0] = cmd;
> + memcpy(&st->data[1], wbuf, wlen);
> if (wo)
> - return dvb_usb_generic_write(d, sndbuf, 1+wlen);
> + return dvb_usb_generic_write(d, st->data, 1 + wlen);
> else
> - return dvb_usb_generic_rw(d, sndbuf, 1+wlen, rbuf,
> rlen, 0);
> + return dvb_usb_generic_rw(d, st->data, 1 + wlen,
> rbuf, rlen, 0); }
>
> /* GPIO */
> diff --git a/drivers/media/usb/dvb-usb/cxusb.h
> b/drivers/media/usb/dvb-usb/cxusb.h index 527ff7905e15..18acda19527a
> 100644 --- a/drivers/media/usb/dvb-usb/cxusb.h
> +++ b/drivers/media/usb/dvb-usb/cxusb.h
> @@ -28,10 +28,15 @@
> #define CMD_ANALOG 0x50
> #define CMD_DIGITAL 0x51
>
> +/* Max transfer size done by I2C transfer functions */
> +#define MAX_XFER_SIZE 80
> +
> struct cxusb_state {
> u8 gpio_write_state[3];
> struct i2c_client *i2c_client_demod;
> struct i2c_client *i2c_client_tuner;
> +
> + unsigned char data[MAX_XFER_SIZE];
> };
>
> #endif
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
