3 files changed, 47 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 10d51c2f10d7..8013b4dd4460 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1243,6 +1243,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
         i8042.notimeout [HW] Ignore timeout condition signalled by controller
         i8042.reset     [HW] Reset the controller during init and cleanup
         i8042.unlock    [HW] Unlock (ignore) the keylock
+        i8042.kbdreset  [HW] Reset device connected to KBD port
 
         i810=           [HW,DRM]
 
diff --git a/drivers/input/serio/i8042-x86ia64io.h b/drivers/input/serio/i8042-x86ia64io.h
index c66d1b53843e..97cdc58d1894 100644
--- a/drivers/input/serio/i8042-x86ia64io.h
+++ b/drivers/input/serio/i8042-x86ia64io.h
@@ -745,6 +745,35 @@ static const struct dmi_system_id __initconst i8042_dmi_dritek_table[] = {
         { }
 };
 
+/*
+ * Some laptops need keyboard reset before probing for the trackpad to get
+ * it detected, initialised & finally work.
+ */
+static const struct dmi_system_id __initconst i8042_dmi_kbdreset_table[] = {
+        {
+                /* Gigabyte P35 v2 - Elantech touchpad */
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "P35V2"),
+                },
+        },
+                {
+                /* Aorus branded Gigabyte X3 Plus - Elantech touchpad */
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "X3"),
+                },
+        },
+        {
+                /* Gigabyte P34 - Elantech touchpad */
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "P34"),
+                },
+        },
+        { }
+};
+
 #endif /* CONFIG_X86 */
 
 #ifdef CONFIG_PNP
@@ -1040,6 +1069,9 @@ static int __init i8042_platform_init(void)
         if (dmi_check_system(i8042_dmi_dritek_table))
                 i8042_dritek = true;
 
+        if (dmi_check_system(i8042_dmi_kbdreset_table))
+                i8042_kbdreset = true;
+
         /*
          * A20 was already enabled during early kernel init. But some buggy
          * BIOSes (in MSI Laptops) require A20 to be enabled using 8042 to
diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c
index f5a98af3b325..804d2e02010a 100644
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -67,6 +67,10 @@ static bool i8042_notimeout;
 module_param_named(notimeout, i8042_notimeout, bool, 0);
 MODULE_PARM_DESC(notimeout, "Ignore timeouts signalled by i8042");
 
+static bool i8042_kbdreset;
+module_param_named(kbdreset, i8042_kbdreset, bool, 0);
+MODULE_PARM_DESC(kbdreset, "Reset device connected to KBD port");
+
 #ifdef CONFIG_X86
 static bool i8042_dritek;
 module_param_named(dritek, i8042_dritek, bool, 0);
@@ -790,6 +794,16 @@ static int __init i8042_check_aux(void)
                 return -1;
 
 /*
+ * Reset keyboard (needed on some laptops to successfully detect
+ * touchpad, e.g., some Gigabyte laptop models with Elantech
+ * touchpads).
+ */
+        if (i8042_kbdreset) {
+                pr_warn("Attempting to reset device connected to KBD port\n");
+                i8042_kbd_write(NULL, (unsigned char) 0xff);
+        }
+
+/*
  * Test AUX IRQ delivery to make sure BIOS did not grab the IRQ and
  * used it for a PCI card or somethig else.
  */