1 files changed, 16 insertions, 2 deletions

diff --git a/drivers/misc/aspeed-lpc-ctrl.c b/drivers/misc/aspeed-lpc-ctrl.c
index 1827b7aa6674..a024f8042259 100644
--- a/drivers/misc/aspeed-lpc-ctrl.c
+++ b/drivers/misc/aspeed-lpc-ctrl.c
@@ -21,6 +21,10 @@
 
 #define DEVICE_NAME     "aspeed-lpc-ctrl"
 
+#define HICR5 0x0
+#define HICR5_ENL2H     BIT(8)
+#define HICR5_ENFWH     BIT(10)
+
 #define HICR7 0x8
 #define HICR8 0xc
 
@@ -155,8 +159,18 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
                 if (rc)
                         return rc;
 
-                return regmap_write(lpc_ctrl->regmap, HICR8,
-                        (~(map.size - 1)) | ((map.size >> 16) - 1));
+                rc = regmap_write(lpc_ctrl->regmap, HICR8,
+                                (~(map.size - 1)) | ((map.size >> 16) - 1));
+                if (rc)
+                        return rc;
+
+                /*
+                 * Enable LPC FHW cycles. This is required for the host to
+                 * access the regions specified.
+                 */
+                return regmap_update_bits(lpc_ctrl->regmap, HICR5,
+                                HICR5_ENFWH | HICR5_ENL2H,
+                                HICR5_ENFWH | HICR5_ENL2H);
         }
 
         return -EINVAL;