From mboxrd@z Thu Jan 1 00:00:00 1970 From: p.ittershagen@googlemail.com (Philipp Ittershagen) Date: Wed, 18 Apr 2012 13:07:09 +0200 Subject: How does the driver initialize corresponding with several same devices ? In-Reply-To: References: <20120418104847.GA23658@peter> Message-ID: <20120418110708.GB23658@peter> To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org On Wed, Apr 18, 2012 at 04:32:12PM +0530, anish singh wrote: > On Wed, Apr 18, 2012 at 4:18 PM, Philipp Ittershagen > 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) ? Greetings, Philipp