ACPI / AC: Add quirk to avoid checking for PMIC with native driver

With commit af3ec837b84b (ACPI / AC: Add a blacklist with PMIC ACPI HIDs
with a native charger driver) a blacklist was introduced to avoid using
the ACPI drivers for AC when a native PMIC driver was already present.
While this is in general a good idea (because of broken DSDT or proprietary
and undocumented ACPI opregions for the ACPI AC devices) there are some
Cherry Trail devices which use a separate charger controller despite the
AXP288 having a builtin charger.

The net effect of blacklisting the ACPI drivers is that on these devices
the AC reporting is broken since the AXP288 PMIC charger bits are not
actually used on this hardware.

This commit adds an ac_do_not_check_pmic quirk for this and sets this on
the 2 devices currently known to use a separate FG controller,
the ECS EF20EA and the Lenovo Ideapad Miix 320.

[hdegoede@redhat.com: Merge the quirk handling and the adding of the DMI
 table entry into 1 commit, add a second DMI entry for the Miix 320.]

Signed-off-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/ac.c

@@ -87,6 +87,7 @@ static int acpi_ac_open_fs(struct inode *inode, struct file *file);
 
 
 static int ac_sleep_before_get_state_ms;
+static int ac_check_pmic = 1;
 
 static struct acpi_driver acpi_ac_driver = {
 	.name = "ac",
@@ -310,13 +311,19 @@ static int acpi_ac_battery_notify(struct notifier_block *nb,
 	return NOTIFY_OK;
 }
 
-static int thinkpad_e530_quirk(const struct dmi_system_id *d)
+static int __init thinkpad_e530_quirk(const struct dmi_system_id *d)
 {
 	ac_sleep_before_get_state_ms = 1000;
 	return 0;
 }
 
-static const struct dmi_system_id ac_dmi_table[] = {
+static int __init ac_do_not_check_pmic_quirk(const struct dmi_system_id *d)
+{
+	ac_check_pmic = 0;
+	return 0;
+}
+
+static const struct dmi_system_id ac_dmi_table[]  __initconst = {
 	{
 	.callback = thinkpad_e530_quirk,
 	.ident = "thinkpad e530",
@@ -325,6 +332,22 @@ static const struct dmi_system_id ac_dmi_table[] = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
 		},
 	},
+	{
+		/* ECS EF20EA */
+		.callback = ac_do_not_check_pmic_quirk,
+		.matches = {
+			DMI_MATCH(DMI_PRODUCT_NAME, "EF20EA"),
+		},
+	},
+	{
+		/* Lenovo Ideapad Miix 320 */
+		.callback = ac_do_not_check_pmic_quirk,
+		.matches = {
+		  DMI_EXACT_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+		  DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "80XF"),
+		  DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "Lenovo MIIX 320-10ICR"),
+		},
+	},
 	{},
 };
 
@@ -384,7 +407,6 @@ end:
 		kfree(ac);
 	}
 
-	dmi_check_system(ac_dmi_table);
 	return result;
 }
 
@@ -442,13 +464,17 @@ static int __init acpi_ac_init(void)
 	if (acpi_disabled)
 		return -ENODEV;
 
-	for (i = 0; i < ARRAY_SIZE(acpi_ac_blacklist); i++)
-		if (acpi_dev_present(acpi_ac_blacklist[i].hid, "1",
-				     acpi_ac_blacklist[i].hrv)) {
-			pr_info(PREFIX "AC: found native %s PMIC, not loading\n",
-				acpi_ac_blacklist[i].hid);
-			return -ENODEV;
-		}
+	dmi_check_system(ac_dmi_table);
+
+	if (ac_check_pmic) {
+		for (i = 0; i < ARRAY_SIZE(acpi_ac_blacklist); i++)
+			if (acpi_dev_present(acpi_ac_blacklist[i].hid, "1",
+					     acpi_ac_blacklist[i].hrv)) {
+				pr_info(PREFIX "AC: found native %s PMIC, not loading\n",
+					acpi_ac_blacklist[i].hid);
+				return -ENODEV;
+			}
+	}
 
 #ifdef CONFIG_ACPI_PROCFS_POWER
 	acpi_ac_dir = acpi_lock_ac_dir();