V4L/DVB (8829): gspca: Have a clean kmalloc-ated buffer for USB exchanges.

The USB buffer may be used for DMA and there may be a caching problem
if the buffer is part of the device structure.
Thanks to Alan Stern.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 1 insertions, 20 deletions

diff --git a/drivers/media/video/gspca/mars.c b/drivers/media/video/gspca/mars.c
index 281475913a61..4d5db47ba8cb 100644
--- a/drivers/media/video/gspca/mars.c
+++ b/drivers/media/video/gspca/mars.c
@@ -100,22 +100,6 @@ static int reg_w(struct gspca_dev *gspca_dev,
         return rc;
 }
 
-static int reg_w_buf(struct gspca_dev *gspca_dev,
-                        __u16 index, __u8 *buf, int len)
-{
-        int rc;
-
-        rc = usb_control_msg(gspca_dev->dev,
-                         usb_sndbulkpipe(gspca_dev->dev, 4),
-                         0x12,
-                         0xc8,          /* ?? */
-                         0,             /* value */
-                         index, buf, len, 500);
-        if (rc < 0)
-                PDEBUG(D_ERR, "reg write [%02x] error %d", index, rc);
-        return rc;
-}
-
 static void bulk_w(struct gspca_dev *gspca_dev,
                    __u16 *pch,
                    __u16 Address)
@@ -175,7 +159,6 @@ static void sd_start(struct gspca_dev *gspca_dev)
         /*
            Initialize the MR97113 chip register
          */
-        data = kmalloc(16, GFP_KERNEL);
         data[0] = 0x00;         /* address */
         data[1] = 0x0c | 0x01;  /* reg 0 */
         data[2] = 0x01;         /* reg 1 */
@@ -195,12 +178,10 @@ static void sd_start(struct gspca_dev *gspca_dev)
         data[10] = 0x5d;        /* reg 9, I2C device address
                                  *      [for PAS5101 (0x40)] [for MI (0x5d)] */
 
-        err_code = reg_w_buf(gspca_dev, data[0], data, 11);
-        kfree(data);
+        err_code = reg_w(gspca_dev, data[0], 11);
         if (err_code < 0)
                 return;
 
-        data = gspca_dev->usb_buf;
         data[0] = 0x23;         /* address */
         data[1] = 0x09;         /* reg 35, append frame header */