commit dadf28a10c3eb29421837a2e413ab869ebd9e168
author Alexey Starikovskiy <astarikovskiy@suse.de> Wed Mar 17 13:14:13 2010 -0400
committer Len Brown <len.brown@intel.com> Wed Mar 17 13:14:13 2010 -0400
tree f4ea66f2ceb12935e3b2c1d3889102dee0dfa778
parent a3d3203e4bb40f253b1541e310dc0f9305be7c84

ACPI: EC: Allow multibyte access to EC

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

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/ec.c

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 1ac28c6..7208a69 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -628,12 +628,12 @@
 
 static acpi_status
 acpi_ec_space_handler(u32 function, acpi_physical_address address,
-		      u32 bits, u64 *value,
+		      u32 bits, u64 *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;
@@ -641,32 +641,15 @@
 	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 = 0; i < bytes; ++i, ++address, ++value)
+		result = (function == ACPI_READ) ?
+			acpi_ec_read(ec, address, value) :
+			acpi_ec_write(ec, address, *value);
 
-	for (i = 8; unlikely(bits - i > 0); i += 8) {
-		++address;
-		if (function == ACPI_READ) {
-			result = acpi_ec_read(ec, address, &temp);
-			(*value) |= ((u64)temp) << i;
-		} else {
-			temp = 0xff & ((*value) >> i);
-			result = acpi_ec_write(ec, address, temp);
-		}
-	}
-
-	if (EC_FLAGS_MSI)
+	if (EC_FLAGS_MSI || bits > 8)
 		acpi_ec_burst_disable(ec);
 
 	switch (result) {