[PATCH V2 5/7] platform/x86: lg-laptop.c: Manage battery limit correctly for 2019 models

[Matan Ziv-Av <matan@xxxxxxxxxxx>]

Read/write battery charging limit using WMBB instead of WMAB for 2019
and newer models.

Signed-off-by: Matan Ziv-Av <matan@xxxxxxxxxxx>
---
 drivers/platform/x86/lg-laptop.c | 40 +++++++++++++++++++++++++-------
 1 file changed, 31 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/x86/lg-laptop.c b/drivers/platform/x86/lg-laptop.c
index d4c49f822394..ccdc93be2a9b 100644
--- a/drivers/platform/x86/lg-laptop.c
+++ b/drivers/platform/x86/lg-laptop.c
@@ -75,6 +75,8 @@ static u32 inited;
 #define INIT_KBD_LED            0x10
 #define INIT_SPARSE_KEYMAP      0x80
 
+static int battery_limit_use_wmbb;
+
 static const struct key_entry wmi_keymap[] = {
 	{KE_KEY, 0x70, {KEY_F15} },	 /* LG control panel (F1) */
 	{KE_KEY, 0x74, {KEY_F13} },	 /* Touchpad toggle (F5) */
@@ -466,7 +468,11 @@ static ssize_t battery_care_limit_store(struct device *dev,
 	if (value == 100 || value == 80) {
 		union acpi_object *r;
 
-		r = lg_wmab(WM_BATT_LIMIT, WM_SET, value);
+		if (!battery_limit_use_wmbb)
+			r = lg_wmab(WM_BATT_LIMIT, WM_SET, value);
+		else
+			r = lg_wmbb(WMBB_BATT_LIMIT, WM_SET, value);
+
 		if (!r)
 			return -EIO;
 
@@ -484,16 +490,29 @@ static ssize_t battery_care_limit_show(struct device *dev,
 	unsigned int status;
 	union acpi_object *r;
 
-	r = lg_wmab(WM_BATT_LIMIT, WM_GET, 0);
-	if (!r)
-		return -EIO;
+	if (!battery_limit_use_wmbb) {
+		r = lg_wmab(WM_BATT_LIMIT, WM_GET, 0);
+		if (!r)
+			return -EIO;
 
-	if (r->type != ACPI_TYPE_INTEGER) {
-		kfree(r);
-		return -EIO;
-	}
+		if (r->type != ACPI_TYPE_INTEGER) {
+			kfree(r);
+			return -EIO;
+		}
+
+		status = r->integer.value;
+	} else {
+		r = lg_wmbb(WMBB_BATT_LIMIT, WM_GET, 0);
+		if (!r)
+			return -EIO;
 
-	status = r->integer.value;
+		if (r->type != ACPI_TYPE_BUFFER) {
+			kfree(r);
+			return -EIO;
+		}
+
+		status = r->buffer.pointer[0x10];
+	}
 	kfree(r);
 	if (status != 80 && status != 100)
 		status = 0;
@@ -648,6 +667,9 @@ static int acpi_add(struct acpi_device *device)
 		}
 	pr_info("product: %s  year: %d  debug v4\n", product, year);
 
+	if (year >= 2019)
+		battery_limit_use_wmbb = 1;
+
 	ret = sysfs_create_group(&pf_device->dev.kobj, &dev_attribute_group);
 	if (ret)
 		goto out_platform_device;
-- 
2.21.0