Hi,
I also see the exact same behavior.
I checked out the history of misc.c, and saw that initialization of
private_data field was added at kernel version 2.6.35.
I see that the problem still exists on android kernel 2.6.39 (http://
android.git.kernel.org).
For now I just commented out the test for private_data inside
pmem_open...
I agree it seems very strange...
Thanks,
Shlomi
On Jun 22, 12:35 pm, xxGrayxx <xgray...@gmail.com> wrote:
> hi all experts.
> I am trying to port a sensor driver (implemented as a misc device) to
> our platform.
> The IP provider told us that Linux kernel patch 96412 (https://
> patchwork.kernel.org/patch/96412/) must to be included,
> and what this patch does is "pass miscdevice pointer via file private
> data" in misc_open function (drivers/char/misc.c)
>
> After I assign this patch to our kernel code, I found a problem ofpmemin open
> function.
> in pmem_open function of the file drivers/misc/pmem.c, non-null
> pointed of file->private_data is checked
>
> if (file->private_data != NULL)
> return -1;
>
> depends on what the patch 96412 does, above code will always return
> -1.
>
> I found that these codes also exist on Android Open Source Project.
> I am wondering if this is a known issue or I have some
> misunderstanding of misc driver andpmembehavior??
--
unsubscribe: android-kernel+unsubscr...@googlegroups.com
website: http://groups.google.com/group/android-kernel
