[PATCH 1/2] ACPI / EC: Cleanup boot EC code using acpi_ec_alloc()

[PATCH 1/2] ACPI / EC: Cleanup boot EC code using acpi_ec_alloc()

[Lv Zheng]

Failure handling of the boot EC code is not tidy. This patch cleans
them up with acpi_ec_alloc().
This patch also changes acpi_ec_dsdt_probe(), always switches the boot EC
from the ECDT one to the DSDT one in this function.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
---
 drivers/acpi/ec.c |   85 ++++++++++++++++++++++++++++++-----------------------
 1 file changed, 48 insertions(+), 37 deletions(-)

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 73c76d6..f63a43a 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1348,13 +1348,9 @@ static void ec_remove_handlers(struct acpi_ec *ec)
 	}
 }
 
-static int acpi_ec_add(struct acpi_device *device)
+static struct acpi_ec *acpi_ec_alloc(void)
 {
-	struct acpi_ec *ec = NULL;
-	int ret;
-
-	strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
-	strcpy(acpi_device_class(device), ACPI_EC_CLASS);
+	struct acpi_ec *ec;
 
 	/* Check for boot EC */
 	if (boot_ec) {
@@ -1365,9 +1361,21 @@ static int acpi_ec_add(struct acpi_device *device)
 			first_ec = NULL;
 	} else {
 		ec = make_acpi_ec();
-		if (!ec)
-			return -ENOMEM;
 	}
+	return ec;
+}
+
+static int acpi_ec_add(struct acpi_device *device)
+{
+	struct acpi_ec *ec = NULL;
+	int ret;
+
+	strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
+	strcpy(acpi_device_class(device), ACPI_EC_CLASS);
+
+	ec = acpi_ec_alloc();
+	if (!ec)
+		return -ENOMEM;
 	if (ec_parse_device(device->handle, 0, ec, NULL) !=
 		AE_CTRL_TERMINATE) {
 			kfree(ec);
@@ -1454,27 +1462,31 @@ static const struct acpi_device_id ec_device_ids[] = {
 int __init acpi_ec_dsdt_probe(void)
 {
 	acpi_status status;
+	struct acpi_ec *ec;
+	int ret;
 
-	if (boot_ec)
-		return 0;
-
+	ec = acpi_ec_alloc();
+	if (!ec)
+		return -ENOMEM;
 	/*
 	 * Finding EC from DSDT if there is no ECDT EC available. When this
 	 * function is invoked, ACPI tables have been fully loaded, we can
 	 * walk namespace now.
 	 */
-	boot_ec = make_acpi_ec();
-	if (!boot_ec)
-		return -ENOMEM;
 	status = acpi_get_devices(ec_device_ids[0].id,
-				  ec_parse_device, boot_ec, NULL);
-	if (ACPI_FAILURE(status) || !boot_ec->handle)
-		return -ENODEV;
-	if (!ec_install_handlers(boot_ec)) {
-		first_ec = boot_ec;
-		return 0;
+				  ec_parse_device, ec, NULL);
+	if (ACPI_FAILURE(status) || !ec->handle) {
+		ret = -ENODEV;
+		goto error;
 	}
-	return -EFAULT;
+	ret = ec_install_handlers(ec);
+
+error:
+	if (ret)
+		kfree(ec);
+	else
+		first_ec = boot_ec = ec;
+	return ret;
 }
 
 #if 0
@@ -1548,12 +1560,13 @@ static struct dmi_system_id ec_dmi_table[] __initdata = {
 
 int __init acpi_ec_ecdt_probe(void)
 {
-	int ret = 0;
+	int ret;
 	acpi_status status;
 	struct acpi_table_ecdt *ecdt_ptr;
+	struct acpi_ec *ec;
 
-	boot_ec = make_acpi_ec();
-	if (!boot_ec)
+	ec = acpi_ec_alloc();
+	if (!ec)
 		return -ENOMEM;
 	/*
 	 * Generate a boot ec context
@@ -1583,22 +1596,20 @@ int __init acpi_ec_ecdt_probe(void)
 		 * MSI MS-171F
 		 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
 		 */
-		boot_ec->command_addr = ecdt_ptr->data.address;
-		boot_ec->data_addr = ecdt_ptr->control.address;
+		ec->command_addr = ecdt_ptr->data.address;
+		ec->data_addr = ecdt_ptr->control.address;
 	} else {
-		boot_ec->command_addr = ecdt_ptr->control.address;
-		boot_ec->data_addr = ecdt_ptr->data.address;
+		ec->command_addr = ecdt_ptr->control.address;
+		ec->data_addr = ecdt_ptr->data.address;
 	}
-	boot_ec->gpe = ecdt_ptr->gpe;
-	boot_ec->handle = ACPI_ROOT_OBJECT;
-	ret = ec_install_handlers(boot_ec);
-	if (!ret)
-		first_ec = boot_ec;
+	ec->gpe = ecdt_ptr->gpe;
+	ec->handle = ACPI_ROOT_OBJECT;
+	ret = ec_install_handlers(ec);
 error:
-	if (ret) {
-		kfree(boot_ec);
-		boot_ec = NULL;
-	}
+	if (ret)
+		kfree(ec);
+	else
+		first_ec = boot_ec = ec;
 	return ret;
 }
 
-- 
1.7.10

[PATCH 2/2] ACPI / EC: Remove wrong ECDT correction quirks

[Lv Zheng]

Our Windows probe result shows that EC._REG is evaluated after evaluating
all _INI/_STA control methods.

With boot EC always switched in acpi_ec_dsdt_probe(), we can see that as
long as there is no EC opregion accesses in the MLC (module level code, AML
code out of any control methods) and in _INI/_STA, there is no need to make
sure that ECDT must be correct.

Bugs of 9399/12461 were reported against an order issue that BAT0/1._STA
evaluations contain EC accesses while the ECDT setting is wrong.

>From the acpidump output posted on bug 9399, we can see that it is actually
a different issue. In this table, if EC._REG is not executed, EC accesses
will be done in a platform specific manner. As we've already ensured not to
execute EC._REG during the eary stage, we can remove the quirks for bug
9399.

>From the acpidump output posted on bug 12461, we can see that it still
needs the quirk. In this table, EC._REG flags a named object whose default
value is One, thus BAT1._STA surely should invoke EC accesses whatever we
invoke EC._REG or not. We have to keep the quirk for it before we can root
cause the issue.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
---
 drivers/acpi/ec.c |   21 +++++----------------
 1 file changed, 5 insertions(+), 16 deletions(-)

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index f63a43a..b1050a0 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1530,6 +1530,11 @@ static int ec_clear_on_resume(const struct dmi_system_id *id)
 	return 0;
 }
 
+/*
+ * Some ECDTs contain wrong register addresses.
+ * MSI MS-171F
+ * https://bugzilla.kernel.org/show_bug.cgi?id=12461
+ */
 static int ec_correct_ecdt(const struct dmi_system_id *id)
 {
 	pr_debug("Detected system needing ECDT address correction.\n");
@@ -1539,16 +1544,6 @@ static int ec_correct_ecdt(const struct dmi_system_id *id)
 
 static struct dmi_system_id ec_dmi_table[] __initdata = {
 	{
-	ec_correct_ecdt, "Asus L4R", {
-	DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
-	DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
-	DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
-	{
-	ec_correct_ecdt, "Asus M6R", {
-	DMI_MATCH(DMI_BIOS_VERSION, "0207"),
-	DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
-	DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
-	{
 	ec_correct_ecdt, "MSI MS-171F", {
 	DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
 	DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL},
@@ -1590,12 +1585,6 @@ int __init acpi_ec_ecdt_probe(void)
 
 	pr_info("EC description table is found, configuring boot EC\n");
 	if (EC_FLAGS_CORRECT_ECDT) {
-		/*
-		 * Asus L4R, Asus M6R
-		 * https://bugzilla.kernel.org/show_bug.cgi?id=9399
-		 * MSI MS-171F
-		 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
-		 */
 		ec->command_addr = ecdt_ptr->data.address;
 		ec->data_addr = ecdt_ptr->control.address;
 	} else {
-- 
1.7.10