If a register width is less than 8, assume the BIOS author thought it was

in units of bytes and adjust accordingly.  This is found at least on the
Sony PCG-505BX.

1 files changed, 12 insertions, 0 deletions

diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
index 57f663e..2b48b52 100644
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -1095,6 +1095,18 @@ acpi_bus_alloc_gas(device_t dev, int *type, int *rid, ACPI_GENERIC_ADDRESS *gas,
 	return (EOPNOTSUPP);
     }
 
+    /*
+     * If the register width is less than 4, assume the BIOS author made a
+     * mistake and assumed the width is in units of bytes not bits.  Ugh.
+     */
+    switch (gas->RegisterBitWidth) {
+    case 1:
+    case 2:
+    case 4:
+	gas->RegisterBitWidth *= 8;
+	break;
+    }
+
     /* Validate the address after we're sure we support the space. */
     if (!ACPI_VALID_ADDRESS(gas->Address) || gas->RegisterBitWidth < 8)
 	return (EINVAL);