diff options
| author | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2016-10-10 08:28:26 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2016-10-14 12:52:27 -0300 |
| commit | 45ae4a5220a43ae79dacb69054a2c7928dd91c94 (patch) | |
| tree | 88bdc0d3765e5f795c4362a8686b8cd3e8bb163c /drivers/media | |
| parent | 3dadf91cb830ac3a6992e539d82ec604fffe8671 (diff) | |
| download | linux-45ae4a5220a43ae79dacb69054a2c7928dd91c94.tar.bz2 | |
[media] cpia2_usb: don't use stack for DMA
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@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/usb/cpia2/cpia2_usb.c | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/drivers/media/usb/cpia2/cpia2_usb.c b/drivers/media/usb/cpia2/cpia2_usb.c index 13620cdf0599..e9100a235831 100644 --- a/drivers/media/usb/cpia2/cpia2_usb.c +++ b/drivers/media/usb/cpia2/cpia2_usb.c @@ -545,18 +545,30 @@ static void free_sbufs(struct camera_data *cam) static int write_packet(struct usb_device *udev, u8 request, u8 * registers, u16 start, size_t size) { + unsigned char *buf; + int ret; + if (!registers || size <= 0) return -EINVAL; - return usb_control_msg(udev, + buf = kmalloc(size, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + memcpy(buf, registers, size); + + ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), request, USB_TYPE_VENDOR | USB_RECIP_DEVICE, start, /* value */ 0, /* index */ - registers, /* buffer */ + buf, /* buffer */ size, HZ); + + kfree(buf); + return ret; } /**************************************************************************** @@ -567,18 +579,32 @@ static int write_packet(struct usb_device *udev, static int read_packet(struct usb_device *udev, u8 request, u8 * registers, u16 start, size_t size) { + unsigned char *buf; + int ret; + if (!registers || size <= 0) return -EINVAL; - return usb_control_msg(udev, + buf = kmalloc(size, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), request, USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_DEVICE, start, /* value */ 0, /* index */ - registers, /* buffer */ + buf, /* buffer */ size, HZ); + + if (ret >= 0) + memcpy(registers, buf, size); + + kfree(buf); + + return ret; } /****************************************************************************** |