ACPI throttling: fix endian bug in acpi_read_throttling_status()

Using a u64 here creates an endian bug.  We store a u32 number in the
top byte which is a larger number than intended on big endian systems.
There is no reason to use a 64 bit data type here, I guess it was just
an oversight.

I removed the initialization to zero as well.  It's needed with a u64
but with a u32, the variable gets initialized properly inside the call
to acpi_os_read_port().

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c
index 605a2954ef17..1d02b7b5ade0 100644
--- a/drivers/acpi/processor_throttling.c
+++ b/drivers/acpi/processor_throttling.c
@@ -769,7 +769,7 @@ static int acpi_read_throttling_status(struct acpi_processor *pr,
                                         u64 *value)
 {
         u32 bit_width, bit_offset;
-        u64 ptc_value;
+        u32 ptc_value;
         u64 ptc_mask;
         struct acpi_processor_throttling *throttling;
         int ret = -1;
@@ -777,12 +777,11 @@ static int acpi_read_throttling_status(struct acpi_processor *pr,
         throttling = &pr->throttling;
         switch (throttling->status_register.space_id) {
         case ACPI_ADR_SPACE_SYSTEM_IO:
-                ptc_value = 0;
                 bit_width = throttling->status_register.bit_width;
                 bit_offset = throttling->status_register.bit_offset;
 
                 acpi_os_read_port((acpi_io_address) throttling->status_register.
-                                  address, (u32 *) &ptc_value,
+                                  address, &ptc_value,
                                   (u32) (bit_width + bit_offset));
                 ptc_mask = (1 << bit_width) - 1;
                 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);