staging: comedi: Add helper macro for comedi usb driver boilerplate

Introduce the module_comedi_usb_driver macro, and the
associated register/unregister functions, which is a
convenience macro for comedi usb driver modules similar
to module_platform_driver. It is intended to be used by
drivers where the init/exit section does nothing but
register/unregister the comedi driver and associated usb
driver. By using this macro it is possible to eliminate
a few lines of boilerplate code per comedi usb driver.

Also, when registering the usb driver check for failure
and unregister the comedi driver.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
H Hartley Sweeten 2012-05-16 18:18:52 -07:00 committed by Greg Kroah-Hartman
parent d896e0e4f4
commit 64255031bd
2 changed files with 46 additions and 0 deletions

View File

@ -329,6 +329,25 @@ void comedi_pci_driver_unregister(struct comedi_driver *, struct pci_driver *);
module_driver(__comedi_driver, comedi_pci_driver_register, \
comedi_pci_driver_unregister, &(__pci_driver))
struct usb_driver;
int comedi_usb_driver_register(struct comedi_driver *, struct usb_driver *);
void comedi_usb_driver_unregister(struct comedi_driver *, struct usb_driver *);
/**
* module_comedi_usb_driver() - Helper macro for registering a comedi USB driver
* @__comedi_driver: comedi_driver struct
* @__usb_driver: usb_driver struct
*
* Helper macro for comedi USB drivers which do not do anything special
* in module init/exit. This eliminates a lot of boilerplate. Each
* module may only use this macro once, and calling it replaces
* module_init() and module_exit()
*/
#define module_comedi_usb_driver(__comedi_driver, __usb_driver) \
module_driver(__comedi_driver, comedi_usb_driver_register, \
comedi_usb_driver_unregister, &(__usb_driver))
void init_polling(void);
void cleanup_polling(void);
void start_polling(struct comedi_device *);

View File

@ -1016,3 +1016,30 @@ void comedi_usb_auto_unconfig(struct usb_interface *intf)
comedi_auto_unconfig(&intf->dev);
}
EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig);
int comedi_usb_driver_register(struct comedi_driver *comedi_driver,
struct usb_driver *usb_driver)
{
int ret;
ret = comedi_driver_register(comedi_driver);
if (ret < 0)
return ret;
ret = usb_register(usb_driver);
if (ret < 0) {
comedi_driver_unregister(comedi_driver);
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(comedi_usb_driver_register);
void comedi_usb_driver_unregister(struct comedi_driver *comedi_driver,
struct usb_driver *usb_driver)
{
usb_deregister(usb_driver);
comedi_driver_unregister(comedi_driver);
}
EXPORT_SYMBOL_GPL(comedi_usb_driver_unregister);