diff options
author | Lv Zheng <lv.zheng@intel.com> | 2016-09-07 11:50:27 +0300 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-09-10 03:33:50 +0300 |
commit | 97cb159fd91d00f8d7d1adeb075503dc0d946bff (patch) | |
tree | 75952cf8e88ada30839ccca69337b14ef8346b6d /drivers/acpi | |
parent | 2a5708409e4e05446eb1a89ecb48641d6fd5d5a9 (diff) | |
download | linux-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')
-rw-r--r-- | drivers/acpi/ec.c | 63 |
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); } |