ACPI: EC: Drop ECDT-based boot_ec as soon as we find DSDT-based one.

ASUS notebooks have numerous problems with EC initialization
This patch tries to work around three known issues reported
in bugzilla 8598, 8709 and 8909/8919.

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

1 files changed, 39 insertions, 51 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 3f7935ab0cf5..9cd7997312e0 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -121,6 +121,7 @@ static struct acpi_ec {
         atomic_t event_count;
         wait_queue_head_t wait;
         struct list_head list;
+        u8 handlers_installed;
 } *boot_ec, *first_ec;
 
 /* --------------------------------------------------------------------------
@@ -680,32 +681,50 @@ ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
         if (ACPI_FAILURE(status))
                 return status;
-
         /* Find and register all query methods */
         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
                             acpi_ec_register_query_methods, ec, NULL);
-
         /* Use the global lock for all EC transactions? */
         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
-
         ec->handle = handle;
-
-        printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
-                          ec->gpe, ec->command_addr, ec->data_addr);
-
         return AE_CTRL_TERMINATE;
 }
 
+static void ec_remove_handlers(struct acpi_ec *ec)
+{
+        if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
+                                ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
+                printk(KERN_ERR PREFIX "failed to remove space handler\n");
+        if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
+                                &acpi_ec_gpe_handler)))
+                printk(KERN_ERR PREFIX "failed to remove gpe handler\n");
+        ec->handlers_installed = 0;
+}
+
 static int acpi_ec_add(struct acpi_device *device)
 {
         struct acpi_ec *ec = NULL;
 
         if (!device)
                 return -EINVAL;
-
         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 
+        /* Check for boot EC */
+        if (boot_ec) {
+                if (boot_ec->handle == device->handle) {
+                        /* Pre-loaded EC from DSDT, just move pointer */
+                        ec = boot_ec;
+                        boot_ec = NULL;
+                        goto end;
+                } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
+                        /* ECDT-based EC, time to shut it down */
+                        ec_remove_handlers(boot_ec);
+                        kfree(boot_ec);
+                        first_ec = boot_ec = NULL;
+                }
+        }
+
         ec = make_acpi_ec();
         if (!ec)
                 return -ENOMEM;
@@ -715,25 +734,14 @@ static int acpi_ec_add(struct acpi_device *device)
                 kfree(ec);
                 return -EINVAL;
         }
-
-        /* Check if we found the boot EC */
-        if (boot_ec) {
-                if (boot_ec->gpe == ec->gpe) {
-                        /* 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;
-                }
-        } else
-                first_ec = ec;
         ec->handle = device->handle;
+      end:
+        if (!first_ec)
+                first_ec = ec;
         acpi_driver_data(device) = ec;
-
         acpi_ec_add_fs(device);
+        printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
+                          ec->gpe, ec->command_addr, ec->data_addr);
         return 0;
 }
 
@@ -756,10 +764,7 @@ static int acpi_ec_remove(struct acpi_device *device, int type)
         acpi_driver_data(device) = NULL;
         if (ec == first_ec)
                 first_ec = NULL;
-
-        /* Don't touch boot EC */
-        if (boot_ec != ec)
-                kfree(ec);
+        kfree(ec);
         return 0;
 }
 
@@ -789,6 +794,8 @@ ec_parse_io_ports(struct acpi_resource *resource, void *context)
 static int ec_install_handlers(struct acpi_ec *ec)
 {
         acpi_status status;
+        if (ec->handlers_installed)
+                return 0;
         status = acpi_install_gpe_handler(NULL, ec->gpe,
                                           ACPI_GPE_EDGE_TRIGGERED,
                                           &acpi_ec_gpe_handler, ec);
@@ -807,6 +814,7 @@ static int ec_install_handlers(struct acpi_ec *ec)
                 return -ENODEV;
         }
 
+        ec->handlers_installed = 1;
         return 0;
 }
 
@@ -823,41 +831,22 @@ static int acpi_ec_start(struct acpi_device *device)
         if (!ec)
                 return -EINVAL;
 
-        /* Boot EC is already working */
-        if (ec != boot_ec)
-                ret = ec_install_handlers(ec);
+        ret = ec_install_handlers(ec);
 
         /* EC is fully operational, allow queries */
         atomic_set(&ec->query_pending, 0);
-
         return ret;
 }
 
 static int acpi_ec_stop(struct acpi_device *device, int type)
 {
-        acpi_status status;
         struct acpi_ec *ec;
-
         if (!device)
                 return -EINVAL;
-
         ec = acpi_driver_data(device);
         if (!ec)
                 return -EINVAL;
-
-        /* 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;
+        ec_remove_handlers(ec);
 
         return 0;
 }
@@ -877,7 +866,7 @@ int __init acpi_ec_ecdt_probe(void)
         status = acpi_get_table(ACPI_SIG_ECDT, 1,
                                 (struct acpi_table_header **)&ecdt_ptr);
         if (ACPI_SUCCESS(status)) {
-                printk(KERN_INFO PREFIX "EC description table is found, configuring boot EC\n\n");
+                printk(KERN_INFO PREFIX "EC description table is found, configuring boot EC\n");
                 boot_ec->command_addr = ecdt_ptr->control.address;
                 boot_ec->data_addr = ecdt_ptr->data.address;
                 boot_ec->gpe = ecdt_ptr->gpe;
@@ -899,7 +888,6 @@ int __init acpi_ec_ecdt_probe(void)
       error:
         kfree(boot_ec);
         boot_ec = NULL;
-
         return -ENODEV;
 }