From 1d82980c99ef2a91459ea39627d8114befb2c895 Mon Sep 17 00:00:00 2001 From: Bob Moore Date: Thu, 8 Aug 2013 15:29:51 +0800 Subject: ACPICA: Make ACPI Power Management Timer (PM Timer) optional. PM Timer is now optional. This support is already in Windows8 and "SHOULD" come out in ACPI 5.0A (if all goes well). The change doesn't affect Linux directly, because it does not rely on the presence of the PM timer. Signed-off-by: Bob Moore Signed-off-by: Lv Zheng Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/hwtimer.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'drivers/acpi/acpica/hwtimer.c') diff --git a/drivers/acpi/acpica/hwtimer.c b/drivers/acpi/acpica/hwtimer.c index 0c1a8bbd05d..2d7d22ebc78 100644 --- a/drivers/acpi/acpica/hwtimer.c +++ b/drivers/acpi/acpica/hwtimer.c @@ -100,8 +100,13 @@ acpi_status acpi_get_timer(u32 * ticks) return_ACPI_STATUS(AE_BAD_PARAMETER); } - status = acpi_hw_read(ticks, &acpi_gbl_FADT.xpm_timer_block); + /* ACPI 5.0A: PM Timer is optional */ + + if (!acpi_gbl_FADT.xpm_timer_block.address) { + return_ACPI_STATUS(AE_SUPPORT); + } + status = acpi_hw_read(ticks, &acpi_gbl_FADT.xpm_timer_block); return_ACPI_STATUS(status); } @@ -148,6 +153,12 @@ acpi_get_timer_duration(u32 start_ticks, u32 end_ticks, u32 * time_elapsed) return_ACPI_STATUS(AE_BAD_PARAMETER); } + /* ACPI 5.0A: PM Timer is optional */ + + if (!acpi_gbl_FADT.xpm_timer_block.address) { + return_ACPI_STATUS(AE_SUPPORT); + } + /* * Compute Tick Delta: * Handle (max one) timer rollovers on 24-bit versus 32-bit timers. -- cgit v1.2.3-70-g09d2