[PATCH v2] [media] dvb-usb-firmware: don't do DMA on stack

[Stefan Brüns]

The buffer allocation for the firmware data was changed in
commit 43fab9793c1f ("dvb-usb: don't use stack for firmware load"),
but the same applies for the reset value.

Signed-off-by: Stefan Brüns <stefan.bru...@rwth-aachen.de>
---
This patch replaces the earlier submission conflicting with commit
43fab9793c1f, which was a subset of the submitted patch.

 drivers/media/usb/dvb-usb/dvb-usb-firmware.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/media/usb/dvb-usb/dvb-usb-firmware.c 
b/drivers/media/usb/dvb-usb/dvb-usb-firmware.c
index 3271b3fee1f4..1f008f354282 100644
--- a/drivers/media/usb/dvb-usb/dvb-usb-firmware.c
+++ b/drivers/media/usb/dvb-usb/dvb-usb-firmware.c
@@ -36,16 +36,19 @@ static int usb_cypress_writemem(struct usb_device *udev,u16 
addr,u8 *data, u8 le
 int usb_cypress_load_firmware(struct usb_device *udev, const struct firmware 
*fw, int type)
 {
        struct hexline *hx;
-       u8 reset;
+       u8 *buf;
+       u8 *reset;
        int ret,pos=0;
+       u16 cpu_cs_register = cypress[type].cpu_cs_register;
 
-       hx = kmalloc(sizeof(*hx), GFP_KERNEL);
-       if (!hx)
+       buf = kmalloc(sizeof(*hx), GFP_KERNEL);
+       if (!buf)
                return -ENOMEM;
+       hx = (struct hexline *)buf;
 
        /* stop the CPU */
-       reset = 1;
-       if ((ret = 
usb_cypress_writemem(udev,cypress[type].cpu_cs_register,&reset,1)) != 1)
+       buf[0] = 1;
+       if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1)
                err("could not stop the USB controller CPU.");
 
        while ((ret = dvb_usb_get_hexline(fw, hx, &pos)) > 0) {
@@ -61,21 +64,21 @@ int usb_cypress_load_firmware(struct usb_device *udev, 
const struct firmware *fw
        }
        if (ret < 0) {
                err("firmware download failed at %d with %d",pos,ret);
-               kfree(hx);
+               kfree(buf);
                return ret;
        }
 
        if (ret == 0) {
                /* restart the CPU */
-               reset = 0;
-               if (ret || 
usb_cypress_writemem(udev,cypress[type].cpu_cs_register,&reset,1) != 1) {
+               buf[0] = 0;
+               if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1) {
                        err("could not restart the USB controller CPU.");
                        ret = -EINVAL;
                }
        } else
                ret = -EIO;
 
-       kfree(hx);
+       kfree(buf);
 
        return ret;
 }
-- 
2.11.0