Merge tag 'module-builtin_driver-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull module_platform_driver replacement from Paul Gortmaker:
 "Replace module_platform_driver with builtin_platform driver in non
  modules.

  We see an increasing number of non-modular drivers using
  modular_driver() type register functions.  There are several downsides
  to letting this continue unchecked:

   - The code can appear modular to a reader of the code, and they won't
     know if the code really is modular without checking the Makefile
     and Kconfig to see if compilation is governed by a bool or
     tristate.

   - Coders of drivers may be tempted to code up an __exit function that
     is never used, just in order to satisfy the required three args of
     the modular registration function.

   - Non-modular code ends up including the <module.h> which increases
     CPP overhead that they don't need.

   - It hinders us from performing better separation of the module init
     code and the generic init code.

  So here we introduce similar macros for builtin drivers.  Then we
  convert builtin drivers (controlled by a bool Kconfig) by making the
  following type of mapping:

    module_platform_driver()       --->  builtin_platform_driver()
    module_platform_driver_probe() --->  builtin_platform_driver_probe().

  The set of drivers that are converted here are just the ones that
  showed up as relying on an implicit include of <module.h> during a
  pending header cleanup.  So we convert them here vs adding an include
  of <module.h> to non-modular code to avoid compile fails.  Additonal
  conversions can be done asynchronously at any time.

  Once again, an unused module_exit function that is removed here
  appears in the diffstat as an outlier wrt all the other changes"

* tag 'module-builtin_driver-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  drivers/clk: convert sunxi/clk-mod0.c to use builtin_platform_driver
  drivers/power: Convert non-modular syscon-reboot to use builtin_platform_driver
  drivers/soc: Convert non-modular soc-realview to use builtin_platform_driver
  drivers/soc: Convert non-modular tegra/pmc to use builtin_platform_driver
  drivers/cpufreq: Convert non-modular s5pv210-cpufreq.c to use builtin_platform_driver
  drivers/cpuidle: Convert non-modular drivers to use builtin_platform_driver
  drivers/platform: Convert non-modular pdev_bus to use builtin_platform_driver
  platform_device: better support builtin boilerplate avoidance

2 files changed, 45 insertions, 0 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index 00ac57c26615..5a31bf3a4024 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -1300,4 +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_ */
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 58f1e75ba105..bba08f44cc97 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -222,6 +222,15 @@ static inline void platform_set_drvdata(struct platform_device *pdev,
 	module_driver(__platform_driver, platform_driver_register, \
 			platform_driver_unregister)
 
+/* builtin_platform_driver() - Helper macro for builtin drivers that
+ * don't do anything special in driver init.  This eliminates some
+ * boilerplate.  Each driver may only use this macro once, and
+ * calling it replaces device_initcall().  Note this is meant to be
+ * a parallel of module_platform_driver() above, but w/o _exit stuff.
+ */
+#define builtin_platform_driver(__platform_driver) \
+	builtin_driver(__platform_driver, platform_driver_register)
+
 /* module_platform_driver_probe() - Helper macro for drivers that don't do
  * anything special in module init/exit.  This eliminates a lot of
  * boilerplate.  Each module may only use this macro once, and
@@ -240,6 +249,20 @@ static void __exit __platform_driver##_exit(void) \
 } \
 module_exit(__platform_driver##_exit);
 
+/* builtin_platform_driver_probe() - Helper macro for drivers that don't do
+ * anything special in device init.  This eliminates some boilerplate.  Each
+ * driver may only use this macro once, and using it replaces device_initcall.
+ * This is meant to be a parallel of module_platform_driver_probe above, but
+ * without the __exit parts.
+ */
+#define builtin_platform_driver_probe(__platform_driver, __platform_probe) \
+static int __init __platform_driver##_init(void) \
+{ \
+	return platform_driver_probe(&(__platform_driver), \
+				     __platform_probe);    \
+} \
+device_initcall(__platform_driver##_init); \
+
 #define platform_create_bundle(driver, probe, res, n_res, data, size) \
 	__platform_create_bundle(driver, probe, res, n_res, data, size, THIS_MODULE)
 extern struct platform_device *__platform_create_bundle(