[media] ce6230: get rid of on-stack dma buffer

usb_control_msg initiates (and waits for completion of) a dma transfer using
the supplied buffer. That buffer thus has to be seperately allocated on
the heap.

In lib/dma_debug.c the function check_for_stack even warns about it:
	WARNING: at lib/dma-debug.c:866 check_for_stack

Signed-off-by: Florian Mickler <florian@mickler.org>
Acked-by: Antti Palosaari <crope@iki.fi>
Reviewed-by: Antti Palosaari <crope@iki.fi>
Tested-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/dvb/dvb-usb/ce6230.c b/drivers/media/dvb/dvb-usb/ce6230.c
index 3df2045b7d2dd48f3c88959d378ab601d17f03e3..6d1a3041540d1c74142949b86d9014a2a2c81788 100644 (file)
--- a/drivers/media/dvb/dvb-usb/ce6230.c
+++ b/drivers/media/dvb/dvb-usb/ce6230.c
@@ -39,7 +39,7 @@ static int ce6230_rw_udev(struct usb_device *udev, struct req_t *req)
        u8 requesttype;
        u16 value;
        u16 index;
-       u8 buf[req->data_len];
+       u8 *buf;
 
        request = req->cmd;
        value = req->value;
@@ -62,6 +62,12 @@ static int ce6230_rw_udev(struct usb_device *udev, struct req_t *req)
                goto error;
        }
 
+       buf = kmalloc(req->data_len, GFP_KERNEL);
+       if (!buf) {
+               ret = -ENOMEM;
+               goto error;
+       }
+
        if (requesttype == (USB_TYPE_VENDOR | USB_DIR_OUT)) {
                /* write */
                memcpy(buf, req->data, req->data_len);
@@ -74,7 +80,7 @@ static int ce6230_rw_udev(struct usb_device *udev, struct req_t *req)
        msleep(1); /* avoid I2C errors */
 
        ret = usb_control_msg(udev, pipe, request, requesttype, value, index,
-                               buf, sizeof(buf), CE6230_USB_TIMEOUT);
+                               buf, req->data_len, CE6230_USB_TIMEOUT);
 
        ce6230_debug_dump(request, requesttype, value, index, buf,
                req->data_len, deb_xfer);
@@ -88,6 +94,7 @@ static int ce6230_rw_udev(struct usb_device *udev, struct req_t *req)
        if (!ret && requesttype == (USB_TYPE_VENDOR | USB_DIR_IN))
                memcpy(req->data, buf, req->data_len);
 
+       kfree(buf);
 error:
        return ret;
 }