ACPI: EC: Allow multibyte access to EC

commit dadf28a10c3eb29421837a2e413ab869ebd upstream

http://bugzilla.kernel.org/show_bug.cgi?id=14667

[bwh: Backport to 2.6.32; same applies to 2.6.33]

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/acpi/acpica/exprep.c b/drivers/acpi/acpica/exprep.c
index 52fec07064f0be7581aa72160d829b521959bfbe..c02d543a2601d6f6c7da0688ad8138ac5309468a 100644 (file)
--- a/drivers/acpi/acpica/exprep.c
+++ b/drivers/acpi/acpica/exprep.c
@@ -468,6 +468,18 @@ acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
 
                acpi_ut_add_reference(obj_desc->field.region_obj);
 
+               /* allow full data read from EC address space */
+               if (obj_desc->field.region_obj->region.space_id ==
+                       ACPI_ADR_SPACE_EC) {
+                       if (obj_desc->common_field.bit_length > 8)
+                               obj_desc->common_field.access_bit_width =
+                               ACPI_ROUND_UP(obj_desc->common_field.
+                                                       bit_length, 8);
+                               obj_desc->common_field.access_byte_width =
+                               ACPI_DIV_8(obj_desc->common_field.
+                                                       access_bit_width);
+               }
+
                ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
                                  "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
                                  obj_desc->field.start_field_bit_offset,

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index f1670e0ef9bb7fb7836ee30af5769bb9430f6f50..45d2aa93258ed3881a33c13fa58d83fb49821e33 100644 (file)
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -588,12 +588,12 @@ static u32 acpi_ec_gpe_handler(void *data)
 
 static acpi_status
 acpi_ec_space_handler(u32 function, acpi_physical_address address,
-                     u32 bits, acpi_integer *value,
+                     u32 bits, acpi_integer *value64,
                      void *handler_context, void *region_context)
 {
        struct acpi_ec *ec = handler_context;
-       int result = 0, i;
-       u8 temp = 0;
+       int result = 0, i, bytes = bits / 8;
+       u8 *value = (u8 *)value64;
 
        if ((address > 0xFF) || !value || !handler_context)
                return AE_BAD_PARAMETER;
@@ -601,32 +601,15 @@ acpi_ec_space_handler(u32 function, acpi_physical_address address,
        if (function != ACPI_READ && function != ACPI_WRITE)
                return AE_BAD_PARAMETER;
 
-       if (bits != 8 && acpi_strict)
-               return AE_BAD_PARAMETER;
-
-       if (EC_FLAGS_MSI)
+       if (EC_FLAGS_MSI || bits > 8)
                acpi_ec_burst_enable(ec);
 
-       if (function == ACPI_READ) {
-               result = acpi_ec_read(ec, address, &temp);
-               *value = temp;
-       } else {
-               temp = 0xff & (*value);
-               result = acpi_ec_write(ec, address, temp);
-       }
-
-       for (i = 8; unlikely(bits - i > 0); i += 8) {
-               ++address;
-               if (function == ACPI_READ) {
-                       result = acpi_ec_read(ec, address, &temp);
-                       (*value) |= ((acpi_integer)temp) << i;
-               } else {
-                       temp = 0xff & ((*value) >> i);
-                       result = acpi_ec_write(ec, address, temp);
-               }
-       }
+       for (i = 0; i < bytes; ++i, ++address, ++value)
+               result = (function == ACPI_READ) ?
+                       acpi_ec_read(ec, address, value) :
+                       acpi_ec_write(ec, address, *value);
 
-       if (EC_FLAGS_MSI)
+       if (EC_FLAGS_MSI || bits > 8)
                acpi_ec_burst_disable(ec);
 
        switch (result) {