1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index 00d2efd674df..4f4e741d34b2 100644
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -28,6 +28,8 @@
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/dmi.h>
+#include <linux/delay.h>
 #ifdef CONFIG_ACPI_PROCFS_POWER
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
@@ -74,6 +76,8 @@ static int acpi_ac_resume(struct device *dev);
 #endif
 static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);
 
+static int ac_sleep_before_get_state_ms;
+
 static struct acpi_driver acpi_ac_driver = {
         .name = "ac",
         .class = ACPI_AC_CLASS,
@@ -252,6 +256,16 @@ static void acpi_ac_notify(struct acpi_device *device, u32 event)
         case ACPI_AC_NOTIFY_STATUS:
         case ACPI_NOTIFY_BUS_CHECK:
         case ACPI_NOTIFY_DEVICE_CHECK:
+                /*
+                 * A buggy BIOS may notify AC first and then sleep for
+                 * a specific time before doing actual operations in the
+                 * EC event handler (_Qxx). This will cause the AC state
+                 * reported by the ACPI event to be incorrect, so wait for a
+                 * specific time for the EC event handler to make progress.
+                 */
+                if (ac_sleep_before_get_state_ms > 0)
+                        msleep(ac_sleep_before_get_state_ms);
+
                 acpi_ac_get_state(ac);
                 acpi_bus_generate_proc_event(device, event, (u32) ac->state);
                 acpi_bus_generate_netlink_event(device->pnp.device_class,
@@ -264,6 +278,24 @@ static void acpi_ac_notify(struct acpi_device *device, u32 event)
         return;
 }
 
+static int thinkpad_e530_quirk(const struct dmi_system_id *d)
+{
+        ac_sleep_before_get_state_ms = 1000;
+        return 0;
+}
+
+static struct dmi_system_id ac_dmi_table[] = {
+        {
+        .callback = thinkpad_e530_quirk,
+        .ident = "thinkpad e530",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
+                },
+        },
+        {},
+};
+
 static int acpi_ac_add(struct acpi_device *device)
 {
         int result = 0;
@@ -312,6 +344,7 @@ static int acpi_ac_add(struct acpi_device *device)
                 kfree(ac);
         }
 
+        dmi_check_system(ac_dmi_table);
         return result;
 }