diff options
Diffstat (limited to 'include/linux/device.h')
-rw-r--r-- | include/linux/device.h | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/include/linux/device.h b/include/linux/device.h index 6558af90c8fe..5a31bf3a4024 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -196,12 +196,41 @@ extern struct kset *bus_get_kset(struct bus_type *bus); extern struct klist *bus_get_device_klist(struct bus_type *bus); /** + * enum probe_type - device driver probe type to try + * Device drivers may opt in for special handling of their + * respective probe routines. This tells the core what to + * expect and prefer. + * + * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well + * whether probed synchronously or asynchronously. + * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which + * probing order is not essential for booting the system may + * opt into executing their probes asynchronously. + * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need + * their probe routines to run synchronously with driver and + * device registration (with the exception of -EPROBE_DEFER + * handling - re-probing always ends up being done asynchronously). + * + * Note that the end goal is to switch the kernel to use asynchronous + * probing by default, so annotating drivers with + * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us + * to speed up boot process while we are validating the rest of the + * drivers. + */ +enum probe_type { + PROBE_DEFAULT_STRATEGY, + PROBE_PREFER_ASYNCHRONOUS, + PROBE_FORCE_SYNCHRONOUS, +}; + +/** * struct device_driver - The basic device driver structure * @name: Name of the device driver. * @bus: The bus which the device of this driver belongs to. * @owner: The module owner. * @mod_name: Used for built-in modules. * @suppress_bind_attrs: Disables bind/unbind via sysfs. + * @probe_type: Type of the probe (synchronous or asynchronous) to use. * @of_match_table: The open firmware table. * @acpi_match_table: The ACPI match table. * @probe: Called to query the existence of a specific device, @@ -235,6 +264,7 @@ struct device_driver { const char *mod_name; /* used for built-in modules */ bool suppress_bind_attrs; /* disables bind/unbind via sysfs */ + enum probe_type probe_type; const struct of_device_id *of_match_table; const struct acpi_device_id *acpi_match_table; @@ -975,6 +1005,7 @@ extern int __must_check device_bind_driver(struct device *dev); extern void device_release_driver(struct device *dev); extern int __must_check device_attach(struct device *dev); extern int __must_check driver_attach(struct device_driver *drv); +extern void device_initial_probe(struct device *dev); extern int __must_check device_reprobe(struct device *dev); /* @@ -1269,4 +1300,26 @@ static void __exit __driver##_exit(void) \ } \ module_exit(__driver##_exit); +/** + * builtin_driver() - Helper macro for drivers that don't do anything + * special in init and have no exit. This eliminates some boilerplate. + * Each driver may only use this macro once, and calling it replaces + * device_initcall (or in some cases, the legacy __initcall). This is + * meant to be a direct parallel of module_driver() above but without + * the __exit stuff that is not used for builtin cases. + * + * @__driver: driver name + * @__register: register function for this driver type + * @...: Additional arguments to be passed to __register + * + * Use this macro to construct bus specific macros for registering + * drivers, and do not use it on its own. + */ +#define builtin_driver(__driver, __register, ...) \ +static int __init __driver##_init(void) \ +{ \ + return __register(&(__driver) , ##__VA_ARGS__); \ +} \ +device_initcall(__driver##_init); + #endif /* _DEVICE_H_ */ |