| Message ID | 1380518035-5319-2-git-send-email-hanjun.guo@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Mon, Sep 30, 2013 at 01:13:52PM +0800, Hanjun Guo wrote: > For some devices especially on platform/I2C/SPI bus, they want to > be initialized earlier than other devices, so the driver use initcall > such as subsys_initcall to make this device initialize earlier. We're trying to move away from needing to do this and to using deferred probing to resolve init ordering issues. Should we not be able to convert the drivers to module_X_driver()?
On Mon, Sep 30, 2013 at 01:13:52PM +0800, Hanjun Guo wrote: > For some devices especially on platform/I2C/SPI bus, they want to > be initialized earlier than other devices, so the driver use initcall > such as subsys_initcall to make this device initialize earlier. And this is something we want to get rid of in favor of deferred probing. > > But for those drivers, lots of them just do nothing special in > xxx_initcall/exit, so introduce a helper macro initcall_driver() to > eliminate lots of boilerplate just like module_driver() did. > > Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> So, NACK because using some *_initcall in drivers should not be encouraged. Thanks, Wolfram
On 2013年09月30日 17:16, Mark Brown wrote: > On Mon, Sep 30, 2013 at 01:13:52PM +0800, Hanjun Guo wrote: >> For some devices especially on platform/I2C/SPI bus, they want to >> be initialized earlier than other devices, so the driver use initcall >> such as subsys_initcall to make this device initialize earlier. > We're trying to move away from needing to do this and to using deferred > probing to resolve init ordering issues. Should we not be able to > convert the drivers to module_X_driver()? Hi Mark, Thanks for your comments. That would be great to move away *_initcall in module driver, and this patch set is not necessary if we can use deferred probe to solve all the init order issues. Thanks Hanjun
On 2013年09月30日 18:15, Wolfram Sang wrote: > On Mon, Sep 30, 2013 at 01:13:52PM +0800, Hanjun Guo wrote: >> For some devices especially on platform/I2C/SPI bus, they want to >> be initialized earlier than other devices, so the driver use initcall >> such as subsys_initcall to make this device initialize earlier. > And this is something we want to get rid of in favor of deferred > probing. > >> But for those drivers, lots of them just do nothing special in >> xxx_initcall/exit, so introduce a helper macro initcall_driver() to >> eliminate lots of boilerplate just like module_driver() did. >> >> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> > So, NACK because using some *_initcall in drivers should not be > encouraged. Ok, got it. I agree with you, *_initcall in module driver is really confusing people :) Thanks Hanjun > > Thanks, > > Wolfram >
diff --git a/include/linux/device.h b/include/linux/device.h index 2a9d6ed..1903f7f 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -1198,4 +1198,31 @@ static void __exit __driver##_exit(void) \ } \ module_exit(__driver##_exit); +/** + * initcall_driver() - Helper macro for drivers that don't do anything + * special in buid-in module xxx_initcall/exit. This eliminates a lot + * of boilerplate. Each driver may only use this macro once, and calling + * it replaces xxx_initcall() and module_exit(). + * + * @__type: initcall type + * @__driver: driver name + * @__register: register function for this driver type + * @__unregister: unregister function for this driver type + * @...: Additional arguments to be passed to __register and __unregister. + * + * Use this macro to construct bus specific macros for registering + * drivers, and do not use it on its own. + */ +#define initcall_driver(__type, __driver, __register, __unregister, ...) \ +static int __init __driver##_init(void) \ +{ \ + return __register(&(__driver) , ##__VA_ARGS__); \ +} \ +__type##_initcall(__driver##_init); \ +static void __exit __driver##_exit(void) \ +{ \ + __unregister(&(__driver) , ##__VA_ARGS__); \ +} \ +module_exit(__driver##_exit); + #endif /* _DEVICE_H_ */
For some devices especially on platform/I2C/SPI bus, they want to be initialized earlier than other devices, so the driver use initcall such as subsys_initcall to make this device initialize earlier. But for those drivers, lots of them just do nothing special in xxx_initcall/exit, so introduce a helper macro initcall_driver() to eliminate lots of boilerplate just like module_driver() did. Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> --- include/linux/device.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+)