DEVICE_SCHEDULE_CALL

Section: Device drivers infrastructure (9)
Updated: February 2011
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NAME

device_schedule_callback_owner - helper to schedule a callback for a device  

SYNOPSIS

int device_schedule_callback_owner(struct device * dev, void (*func) (struct device *), struct module * owner);
 

ARGUMENTS

dev

device.

func

callback function to invoke later.

owner

module owning the callback routine
 

DESCRIPTION

Attribute methods must not unregister themselves or their parent device (which would amount to the same thing). Attempts to do so will deadlock, since unregistration is mutually exclusive with driver callbacks.

Instead methods can call this routine, which will attempt to allocate and schedule a workqueue request to call back func with dev as its argument in the workqueue's process context. dev will be pinned until func returns.

This routine is usually called via the inline device_schedule_callback, which automatically sets owner to THIS_MODULE.

Returns 0 if the request was submitted, -ENOMEM if storage could not be allocated, -ENODEV if a reference to owner isn't available.  

NOTE

This routine won't work if CONFIG_SYSFS isn't set! It uses an underlying sysfs routine (since it is intended for use by attribute methods), and if sysfs isn't available you'll get nothing but -ENOSYS.  

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