diff options
| author | Jean-Francois Moine <moinejf@free.fr> | 2008-09-03 17:12:19 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2008-09-03 18:37:42 -0300 |
| commit | 8295d99ee5340f1e62b53c8adc979e0789299445 (patch) | |
| tree | d537fd27c8079bec09b513845dc2cf9c21234482 /drivers/media/video/gspca/sonixj.c | |
| parent | 91de65ac00f976c972940bedd9dbfe38bb8bfec3 (diff) | |
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>
Diffstat (limited to 'drivers/media/video/gspca/sonixj.c')
| -rw-r--r-- | drivers/media/video/gspca/sonixj.c | 43 |
1 files changed, 20 insertions, 23 deletions
diff --git a/drivers/media/video/gspca/sonixj.c b/drivers/media/video/gspca/sonixj.c index feb17dbdd7b..5697959e724 100644 --- a/drivers/media/video/gspca/sonixj.c +++ b/drivers/media/video/gspca/sonixj.c @@ -613,10 +613,16 @@ static const __u8 qtable4[] = { 0x29, 0x29, 0x29, 0x29 }; -/* read <len> bytes (len < sizeof gspca_dev->usb_buf) to gspca_dev->usb_buf */ +/* read <len> bytes to gspca_dev->usb_buf */ static void reg_r(struct gspca_dev *gspca_dev, __u16 value, int len) { +#ifdef GSPCA_DEBUG + if (len > USB_BUF_SZ) { + err("reg_r: buffer overflow"); + return; + } +#endif usb_control_msg(gspca_dev->dev, usb_rcvctrlpipe(gspca_dev->dev, 0), 0, @@ -649,29 +655,20 @@ static void reg_w(struct gspca_dev *gspca_dev, { PDEBUG(D_USBO, "reg_w [%02x] = %02x %02x ..", value, buffer[0], buffer[1]); - if (len <= sizeof gspca_dev->usb_buf) { - memcpy(gspca_dev->usb_buf, buffer, len); - usb_control_msg(gspca_dev->dev, - usb_sndctrlpipe(gspca_dev->dev, 0), - 0x08, - USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, - value, 0, - gspca_dev->usb_buf, len, - 500); - } else { - __u8 *tmpbuf; - - tmpbuf = kmalloc(len, GFP_KERNEL); - memcpy(tmpbuf, buffer, len); - usb_control_msg(gspca_dev->dev, - usb_sndctrlpipe(gspca_dev->dev, 0), - 0x08, - USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, - value, 0, - tmpbuf, len, - 500); - kfree(tmpbuf); +#ifdef GSPCA_DEBUG + if (len > USB_BUF_SZ) { + err("reg_w: buffer overflow"); + return; } +#endif + memcpy(gspca_dev->usb_buf, buffer, len); + usb_control_msg(gspca_dev->dev, + usb_sndctrlpipe(gspca_dev->dev, 0), + 0x08, + USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, + value, 0, + gspca_dev->usb_buf, len, + 500); } /* I2C write 1 byte */ |