On Fri, Sep 25, 2015 at 6:29 PM, Thierry Reding <thierry.reding@xxxxxxxxx> wrote: > From: Thierry Reding <treding@xxxxxxxxxx> > > Some modules register several sub-drivers. Provide a helper that makes > it easy to register and unregister a list of sub-drivers, as well as > unwind properly on error. > > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index f80aaaf9f610..68c58c43e45a 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -711,6 +711,67 @@ err_out: > } > EXPORT_SYMBOL_GPL(__platform_create_bundle); > > +/** > + * __platform_register_drivers - register an array of platform drivers > + * @drivers: an array of drivers to register > + * @count: the number of drivers to register > + * @owner: module owning the drivers > + * > + * Registers platform drivers specified by an array. On failure to register a > + * driver, all previously registered drivers will be unregistered. Callers of > + * this API should use platform_unregister_drivers() to unregister drivers in > + * the reverse order. > + * > + * Returns: 0 on success or a negative error code on failure. > + */ > +int __platform_register_drivers(struct platform_driver * const *drivers, > + unsigned int count, struct module *owner) > +{ > + unsigned int i; > + int err; > + > + for (i = 0; i < count; i++) { > + pr_debug("registering platform driver %ps\n", drivers[i]); > + > + err = __platform_driver_register(drivers[i], owner); > + if (err < 0) { > + pr_err("failed to register platform driver %ps: %d\n", > + drivers[i], err); Would platform_unregister_drivers(drivers, i); work? > + goto error; > + } > + } > + > + return 0; > + > +error: > + while (i--) { I think Jani was confused since often idiom is 'while (--i >=0)' is used. > + pr_debug("unregistering platform driver %ps\n", drivers[i]); > + platform_driver_unregister(drivers[i]); > + } > + > + return err; > +} > +EXPORT_SYMBOL_GPL(__platform_register_drivers); > + > +/** > + * platform_unregister_drivers - unregister an array of platform drivers > + * @drivers: an array of drivers to unregister > + * @count: the number of drivers to unregister > + * > + * Unegisters platform drivers specified by an array. This is typically used > + * to complement an earlier call to platform_register_drivers(). Drivers are > + * unregistered in the reverse order in which they were registered. > + */ > +void platform_unregister_drivers(struct platform_driver * const *drivers, > + unsigned int count) > +{ > + while (count--) { > + pr_debug("unregistering platform driver %ps\n", drivers[count]); > + platform_driver_unregister(drivers[count]); > + } > +} > +EXPORT_SYMBOL_GPL(platform_unregister_drivers); -- With Best Regards, Andy Shevchenko _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel