kernelnewbies.kernelnewbies.org archive mirror
 help / color / mirror / Atom feed
From: anish198519851985@gmail.com (anish singh)
To: kernelnewbies@lists.kernelnewbies.org
Subject: How does the driver initialize corresponding with several same devices ?
Date: Wed, 18 Apr 2012 16:41:19 +0530	[thread overview]
Message-ID: <CAK7N6vqfsYOG71taAy2n9ptSyuKGk4Z1oZs7aM0P_rLA421uNg@mail.gmail.com> (raw)
In-Reply-To: <20120418110708.GB23658@peter>

On Wed, Apr 18, 2012 at 4:37 PM, Philipp Ittershagen
<p.ittershagen@googlemail.com> wrote:
> On Wed, Apr 18, 2012 at 04:32:12PM +0530, anish singh wrote:
>> On Wed, Apr 18, 2012 at 4:18 PM, Philipp Ittershagen
>> <p.ittershagen@googlemail.com> wrote:
>> > On Wed, Apr 18, 2012 at 05:16:01PM +0800, Li Haifeng wrote:
>> >> I make a driver module and built in the kernel.?There are three devices use
>> >> the same driver on the hardware platform.?To use each device, the probe
>> >> function of the driver module should be probed. So, the driver module is
>> >> registered in the kernel.
>> >>
>> >> My question is, how times should the probe function of the driver be called
>> >> and create nodes in devfs to corresponding with the three devices?
>> >
>> > It depends on what your architecture supports. If you have support for device
>> > tree, your entry in the device tree will make the subsystem call your probe
>> > function for each device it finds. You can then check the `compatible` entry
>> > of the device node and your driver is then able to register itself to the
>> > kernel subsystem.
>> Without device tree what would be your answer as i guess device
>> tree has come recently in picture but not sure.
>
> Let me rephrase your question and see if I understand it correctly. You have a
> probe function which already gets called for each device in your platform and
> you want to know how to make each device accessible in userspace (using i.e.
> devfs nodes) ?
I think he wants to know how will he differentiate different devices as probe of
the driver will be called three times for all the devices.Right?
>
> Greetings,
>
> ?Philipp

  reply	other threads:[~2012-04-18 11:11 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CAFNq8R4U-1c4ONn8EDZ7-ZgO2BC0r1JvsBxKsD1MeBzRndJr-w@mail.gmail.com>
     [not found] ` <CAFNq8R4dF+QPvPcy5+SSOBketAdzyJfJ6WonX0Z8OHztcvsYvA@mail.gmail.com>
2012-04-18  9:16   ` How does the driver initialize corresponding with several same devices ? Li Haifeng
2012-04-18 10:48     ` Philipp Ittershagen
     [not found]       ` <CAK7N6vpEL21SUMWk05ODDY+JE4gMDz7A17zfZDnsfU-=Nw6hiA@mail.gmail.com>
2012-04-18 11:07         ` Philipp Ittershagen
2012-04-18 11:11           ` anish singh [this message]
2012-04-18 13:38             ` Li Haifeng
2012-04-18 10:59     ` Javier Martinez Canillas
2012-04-18 11:01       ` Javier Martinez Canillas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAK7N6vqfsYOG71taAy2n9ptSyuKGk4Z1oZs7aM0P_rLA421uNg@mail.gmail.com \
    --to=anish198519851985@gmail.com \
    --cc=kernelnewbies@lists.kernelnewbies.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).