[PATCH 18/20] clocksource / acpi: Add macro CLOCKSOURCE_ACPI_DECLARE

[Hanjun Guo]

From: Amit Daniel Kachhap <amit.daniel at samsung.com>

This macro does the same job as CLOCKSOURCE_OF_DECLARE. The device
name from the ACPI timer table is matched with all the registered
timer controllers and matching initialisation routine is invoked.

Signed-off-by: Amit Daniel Kachhap <amit.daniel at samsung.com>
Signed-off-by: Hanjun Guo <hanjun.guo at linaro.org>
---
 include/asm-generic/vmlinux.lds.h |   10 ++++++++++
 include/linux/clocksource.h       |   12 ++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index bc2121f..3216bee 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -148,6 +148,15 @@
 #define CLKSRC_OF_TABLES()
 #endif
 
+#ifdef CONFIG_ACPI
+#define CLKSRC_ACPI_TABLES() . = ALIGN(8);				\
+			   VMLINUX_SYMBOL(__clksrc_acpi_table) = .;	\
+			   *(__clksrc_acpi_table)			\
+			   *(__clksrc_acpi_table_end)
+#else
+#define CLKSRC_ACPI_TABLES()
+#endif
+
 #ifdef CONFIG_IRQCHIP
 #define IRQCHIP_OF_MATCH_TABLE()					\
 	. = ALIGN(8);							\
@@ -491,6 +500,7 @@
 	MEM_DISCARD(init.rodata)					\
 	CLK_OF_TABLES()							\
 	CLKSRC_OF_TABLES()						\
+	CLKSRC_ACPI_TABLES()						\
 	KERNEL_DTB()							\
 	IRQCHIP_OF_MATCH_TABLE()
 
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 67301a4..1d500cf 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -341,6 +341,8 @@ extern int clocksource_i8253_init(void);
 
 struct device_node;
 typedef void(*clocksource_of_init_fn)(struct device_node *);
+typedef void(*clocksource_acpi_init_fn)(void);
+
 #ifdef CONFIG_CLKSRC_OF
 extern void clocksource_of_init(void);
 
@@ -358,4 +360,14 @@ static inline void clocksource_of_init(void) {}
 		     .data = (fn == (clocksource_of_init_fn)NULL) ? fn : fn }
 #endif
 
+#ifdef CONFIG_ACPI
+#define CLOCKSOURCE_ACPI_DECLARE(name, compat, fn)			\
+	static const struct acpi_device_id __clksrc_acpi_table_##name	\
+		__used __section(__clksrc_acpi_table)			\
+		 = { .id = compat,				\
+		     .driver_data = (kernel_ulong_t)fn }
+#else
+#define CLOCKSOURCE_ACPI_DECLARE(name, compat, fn)
+#endif
+
 #endif /* _LINUX_CLOCKSOURCE_H */
-- 
1.7.9.5