Hi, thanks for your answwer,
Le 27/11/2017 à 17:38, Matthew Wilcox a écrit :
On Mon, Nov 27, 2017 at 04:18:42PM +0100, Christophe LEROY wrote:
When registering a device node with device_create(), it is possible to pass
a drvdata pointer.
How can I retrieve that drvdata pointer from the open() fops ? I've not been
able to find any exemple.
You're not supposed to do it that way ... assuming you're talking about
a character device, you embed the cdev in your own data structure and
do this:
struct my_struct *my = container_of(inode->i_cdev, struct my_struct, cdev);
after calling:
cdev_init(&my->cdev, &my_dev_fops);
You'll use the drvdata when trying to go from the struct device to
'my_struct'. There's no struct device in struct cdev. I mean, you
could probably get to it, but it's easier if you just do it the way that
everybody else does it.
I see, you are right I'm talking about a character device.
The driver I'm trying to clean is using __register_chrdev() which hides
cdev and cdev operations. Does it mean it has to be changed to do cdev
operations explicitely ?
