On Sat, Nov 10, 2012 at 2:27 AM, Jon Mason <jon.ma...@intel.com> wrote:
> device_control is an optional and not implemented in all DMA drivers.
> Any calls to these will result in a NULL pointer dereference. dmatest
> makes two of these calls when completing the kernel thread and removing
> the module. These are corrected by calling the dmaengine_device_control
> wrapper and checking for a non-existant device_control function pointer
> there.
>
> Signed-off-by: Jon Mason <jon.ma...@intel.com>
> CC: Vinod Koul <vinod.k...@intel.com>
> CC: Dan Williams <d...@fb.com>
> ---
> drivers/dma/dmatest.c | 4 ++--
> include/linux/dmaengine.h | 5 ++++-
> 2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index d3201e4..e0004fb 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -608,7 +608,10 @@ static inline int dmaengine_device_control(struct
> dma_chan *chan,
> enum dma_ctrl_cmd cmd,
> unsigned long arg)
> {
> - return chan->device->device_control(chan, cmd, arg);
> + if (chan->device->device_control)
> + return chan->device->device_control(chan, cmd, arg);
> + else
> + return -EINVAL;
-ENOTSUPP or -ENOSYS ??
@Dan: I believe i don't have to send another version now. Correct??
--
viresh
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