[ACPI] acpi_register_gsi() can return error

Current acpi_register_gsi() function has no way to indicate errors to its
callers even though acpi_register_gsi() can fail to register gsi because of
some reasons (out of memory, lack of interrupt vectors, incorrect BIOS, and so
on).  As a result, caller of acpi_register_gsi() cannot handle the case that
acpi_register_gsi() fails.  I think failure of acpi_register_gsi() should be
handled properly.

This series of patches changes acpi_register_gsi() to return negative value on
error, and also changes callers of acpi_register_gsi() to handle failure of
acpi_register_gsi().

This patch changes the type of return value of acpi_register_gsi() from
"unsigned int" to "int" to indicate an error.  If acpi_register_gsi() fails to
register gsi, it returns negative value.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>

3 files changed, 11 insertions, 3 deletions

diff --git a/arch/i386/kernel/acpi/boot.c b/arch/i386/kernel/acpi/boot.c
index 848bb97af7ca..364f4b7c4e3e 100644
--- a/arch/i386/kernel/acpi/boot.c
+++ b/arch/i386/kernel/acpi/boot.c
@@ -457,7 +457,11 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
         return 0;
 }
 
-unsigned int acpi_register_gsi(u32 gsi, int edge_level, int active_high_low)
+/*
+ * success: return IRQ number (>=0)
+ * failure: return < 0
+ */
+int acpi_register_gsi(u32 gsi, int edge_level, int active_high_low)
 {
         unsigned int irq;
         unsigned int plat_gsi = gsi;
diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 1c118b72df3c..7513ff9361a0 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -565,7 +565,11 @@ acpi_numa_arch_fixup (void)
 }
 #endif /* CONFIG_ACPI_NUMA */
 
-unsigned int
+/*
+ * success: return IRQ number (>=0)
+ * failure: return < 0
+ */
+int
 acpi_register_gsi (u32 gsi, int edge_level, int active_high_low)
 {
         if (has_8259 && gsi < 16)
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index ca0cd240cee0..9378bcde73a4 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -432,7 +432,7 @@ static inline int acpi_boot_table_init(void)
 
 #endif  /*!CONFIG_ACPI_BOOT*/
 
-unsigned int acpi_register_gsi (u32 gsi, int edge_level, int active_high_low);
+int acpi_register_gsi (u32 gsi, int edge_level, int active_high_low);
 int acpi_gsi_to_irq (u32 gsi, unsigned int *irq);
 
 /*