ACPI: EC: revert fix for bugzilla 8709

This is a manual revert of 7c010de7506954e973abfab5c5999c5a97f7a73e,
a fix that broke another ASUS in 8909 and 8919.

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

1 files changed, 31 insertions, 16 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 56bee9e065cf..43749c86861f 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -696,14 +696,6 @@ ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
         return AE_CTRL_TERMINATE;
 }
 
-static void ec_remove_handlers(struct acpi_ec *ec)
-{
-        acpi_remove_address_space_handler(ec->handle,
-                                          ACPI_ADR_SPACE_EC,
-                                          &acpi_ec_space_handler);
-        acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
-}
-
 static int acpi_ec_add(struct acpi_device *device)
 {
         struct acpi_ec *ec = NULL;
@@ -727,13 +719,16 @@ static int acpi_ec_add(struct acpi_device *device)
         /* Check if we found the boot EC */
         if (boot_ec) {
                 if (boot_ec->gpe == ec->gpe) {
-                        ec_remove_handlers(boot_ec);
-                        mutex_destroy(&boot_ec->lock);
-                        kfree(boot_ec);
-                        first_ec = boot_ec = NULL;
+                        /* We might have incorrect info for GL at boot time */
+                        mutex_lock(&boot_ec->lock);
+                        boot_ec->global_lock = ec->global_lock;
+                        /* Copy handlers from new ec into boot ec */
+                        list_splice(&ec->list, &boot_ec->list);
+                        mutex_unlock(&boot_ec->lock);
+                        kfree(ec);
+                        ec = boot_ec;
                 }
-        }
-        if (!first_ec)
+        } else
                 first_ec = ec;
         ec->handle = device->handle;
         acpi_driver_data(device) = ec;
@@ -762,6 +757,9 @@ static int acpi_ec_remove(struct acpi_device *device, int type)
         if (ec == first_ec)
                 first_ec = NULL;
 
+        /* Don't touch boot EC */
+        if (boot_ec != ec)
+                kfree(ec);
         return 0;
 }
 
@@ -825,7 +823,9 @@ static int acpi_ec_start(struct acpi_device *device)
         if (!ec)
                 return -EINVAL;
 
-        ret = ec_install_handlers(ec);
+        /* Boot EC is already working */
+        if (ec != boot_ec)
+                ret = ec_install_handlers(ec);
 
         /* EC is fully operational, allow queries */
         atomic_set(&ec->query_pending, 0);
@@ -835,6 +835,7 @@ static int acpi_ec_start(struct acpi_device *device)
 
 static int acpi_ec_stop(struct acpi_device *device, int type)
 {
+        acpi_status status;
         struct acpi_ec *ec;
 
         if (!device)
@@ -843,7 +844,21 @@ static int acpi_ec_stop(struct acpi_device *device, int type)
         ec = acpi_driver_data(device);
         if (!ec)
                 return -EINVAL;
-        ec_remove_handlers(ec);
+
+        /* Don't touch boot EC */
+        if (ec == boot_ec)
+                return 0;
+
+        status = acpi_remove_address_space_handler(ec->handle,
+                                                   ACPI_ADR_SPACE_EC,
+                                                   &acpi_ec_space_handler);
+        if (ACPI_FAILURE(status))
+                return -ENODEV;
+
+        status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
+        if (ACPI_FAILURE(status))
+                return -ENODEV;
+
         return 0;
 }