From: kristof@sigsegv.be (Kristof Provost)
To: kernelnewbies@lists.kernelnewbies.org
Subject: User space <==> kernel space for device wakeups.
Date: Wed, 8 Oct 2014 17:57:50 +0200 [thread overview]
Message-ID: <20141008155750.GF2017@vega.codepro.be> (raw)
In-Reply-To: <CAC-LjFv7pDX0RRup7tywrRRJEf6_tCoVaTgqFCd0fVxZSMkbhA@mail.gmail.com>
On 2014-10-08 21:14:43 (+0530), Jeshwanth Kumar N K <jeshkumar555@gmail.com> wrote:
> Wayback when I was working on some project to wake up userspace program for
> every rising edge in GPIO pin (hall sensor), I use to send signal to the
> PID from kernel, before that userspace has to register its PID with kernel
> module.
>
I've seen a certain vendor[1] do something similar. They saved the task
pointer for whichever process made the magical ioctl() call and used it
to send signals from the interrupt handler. It worked, right up to the
point where the process went away and then the kernel panicked.
Regards,
Kristof
[1] Who shall remain nameless here. Naming them would only give people
the impression that other vendors might be better.
next prev parent reply other threads:[~2014-10-08 15:57 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-08 7:39 User space <==> kernel space for device wakeups manty kuma
2014-10-08 13:29 ` Greg KH
2014-10-08 15:44 ` Jeshwanth Kumar N K
2014-10-08 15:57 ` Kristof Provost [this message]
2014-10-08 16:25 ` Greg Kroah-Hartman
2014-10-08 16:31 ` Jeshwanth Kumar N K
2014-10-08 16:38 ` Greg Kroah-Hartman
2014-10-08 16:53 ` Jeshwanth Kumar N K
2014-10-08 17:32 ` Greg Kroah-Hartman
2014-10-08 17:47 ` Jeshwanth Kumar N K
2014-10-09 15:18 ` buyitian
2014-10-08 18:30 ` Jinqiang Zeng
2014-10-09 1:38 ` manty kuma
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