Thanks Anish ..
I got your point .
I was using
struct inode *inode = file->f_dentry->d_inode;
 min = iminor(inode);

to see which node has been opened,
I wanted to make sure myself the correct/best way of
getting this information.

Praveen


On Wed, Nov 16, 2011 at 8:02 PM, anish kumar [off-list ref]wrote:

On Wed, 2011-11-16 at 18:00 +0530, Praveen kumar wrote:

quoted

Hi All,
        I have a I2C chip driver,and there are two identical chips on
two different i2c bus.
I have registered the driver and initialized it and created two
nodes /dev/chip_0 and /dev/chip_1

If I open the node from user how will I make driver identify which
device to access .ie in the ioctl.

So in your ioctl call you want to get the device structure right?
If yes then have a look at scull/main.c file in scull folder at below
location.
git://github.com/martinezjavier/ldd3.git

Basically you need to set private_data of filp at open time with device
information and get the private_data from filp in ioctl.
If you don't understand then just have a look at the file I mentioned.

quoted

Am I clear ???

Praveen


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