summaryrefslogtreecommitdiff
path: root/drivers/acpi/ec.c
diff options
context:
space:
mode:
authorLv Zheng <lv.zheng@intel.com>2016-09-07 11:50:27 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2016-09-10 03:33:50 +0300
commit97cb159fd91d00f8d7d1adeb075503dc0d946bff (patch)
tree75952cf8e88ada30839ccca69337b14ef8346b6d /drivers/acpi/ec.c
parent2a5708409e4e05446eb1a89ecb48641d6fd5d5a9 (diff)
downloadlinux-97cb159fd91d00f8d7d1adeb075503dc0d946bff.tar.xz
ACPI / EC: Fix issues related to boot_ec
There are issues related to the boot_ec: 1. If acpi_ec_remove() is invoked, boot_ec will also be freed, this is not expected as the boot_ec could be enumerated via ECDT. 2. Address space handler installation/unstallation lead to unexpected _REG evaluations. This patch adds acpi_is_boot_ec() check to be used to fix the above issues. However, since acpi_ec_remove() actually won't be invoked, this patch doesn't handle the reference counting of "struct acpi_ec", it only ensures the correctness of the boot_ec destruction during the boot. Link: https://bugzilla.kernel.org/show_bug.cgi?id=153511 Reported-and-tested-by: Jonh Henderson <jw.hendy@gmail.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/ec.c')
-rw-r--r--drivers/acpi/ec.c63
1 files changed, 49 insertions, 14 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 2ae9194cc630..680531062160 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1536,6 +1536,37 @@ static int acpi_config_boot_ec(struct acpi_ec *ec, acpi_handle handle,
return ret;
}
+static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle)
+{
+ struct acpi_table_ecdt *ecdt_ptr;
+ acpi_status status;
+ acpi_handle handle;
+
+ status = acpi_get_table(ACPI_SIG_ECDT, 1,
+ (struct acpi_table_header **)&ecdt_ptr);
+ if (ACPI_FAILURE(status))
+ return false;
+
+ status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
+ if (ACPI_FAILURE(status))
+ return false;
+
+ *phandle = handle;
+ return true;
+}
+
+static bool acpi_is_boot_ec(struct acpi_ec *ec)
+{
+ if (!boot_ec)
+ return false;
+ if (ec->handle == boot_ec->handle &&
+ ec->gpe == boot_ec->gpe &&
+ ec->command_addr == boot_ec->command_addr &&
+ ec->data_addr == boot_ec->data_addr)
+ return true;
+ return false;
+}
+
static int acpi_ec_add(struct acpi_device *device)
{
struct acpi_ec *ec = NULL;
@@ -1553,7 +1584,14 @@ static int acpi_ec_add(struct acpi_device *device)
goto err_alloc;
}
- ret = acpi_config_boot_ec(ec, device->handle, true, false);
+ if (acpi_is_boot_ec(ec)) {
+ boot_ec_is_ecdt = false;
+ acpi_handle_debug(ec->handle, "duplicated.\n");
+ acpi_ec_free(ec);
+ ec = boot_ec;
+ ret = acpi_config_boot_ec(ec, ec->handle, true, false);
+ } else
+ ret = acpi_ec_setup(ec, true);
if (ret)
goto err_query;
@@ -1566,12 +1604,15 @@ static int acpi_ec_add(struct acpi_device *device)
/* Reprobe devices depending on the EC */
acpi_walk_dep_device_list(ec->handle);
+ acpi_handle_debug(ec->handle, "enumerated.\n");
return 0;
err_query:
- acpi_ec_remove_query_handlers(ec, true, 0);
+ if (ec != boot_ec)
+ acpi_ec_remove_query_handlers(ec, true, 0);
err_alloc:
- acpi_ec_free(ec);
+ if (ec != boot_ec)
+ acpi_ec_free(ec);
return ret;
}
@@ -1583,11 +1624,13 @@ static int acpi_ec_remove(struct acpi_device *device)
return -EINVAL;
ec = acpi_driver_data(device);
- ec_remove_handlers(ec);
release_region(ec->data_addr, 1);
release_region(ec->command_addr, 1);
device->driver_data = NULL;
- acpi_ec_free(ec);
+ if (ec != boot_ec) {
+ ec_remove_handlers(ec);
+ acpi_ec_free(ec);
+ }
return 0;
}
@@ -1659,8 +1702,6 @@ error:
*/
int __init acpi_ec_ecdt_start(void)
{
- struct acpi_table_ecdt *ecdt_ptr;
- acpi_status status;
acpi_handle handle;
if (!boot_ec)
@@ -1672,17 +1713,11 @@ int __init acpi_ec_ecdt_start(void)
if (!boot_ec_is_ecdt)
return -ENODEV;
- status = acpi_get_table(ACPI_SIG_ECDT, 1,
- (struct acpi_table_header **)&ecdt_ptr);
- if (ACPI_FAILURE(status))
- return -ENODEV;
-
/*
* At this point, the namespace and the GPE is initialized, so
* start to find the namespace objects and handle the events.
*/
- status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
- if (ACPI_FAILURE(status))
+ if (!acpi_ec_ecdt_get_handle(&handle))
return -ENODEV;
return acpi_config_boot_ec(boot_ec, handle, true, true);
}