mb/google/dedede/var/magolor: Add stylus function

Add the stylus field in fw_config.
Update devicetree and gpio to handle stylus pen detection.

BUG=b:167983049
TEST=Build firmware and check behavior as following:
     1) Set the fw_config "bit4=1" for pen present:
     	Wake up from suspend when pen is removed from the garage.
     	Present the stylus menu when pen is removed from the garage.
     2) Set the fw_config "bit4=0" for pen absent:
        Wake up and present menu will not work when pen is removed
	form the garage.

Change-Id: I62489bb289b18f9aa0823005224eda3ef5218e03
Signed-off-by: Ren Kuo <ren.kuo@quanta.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/60185
Reviewed-by: Aseda Aboagye <aaboagye@google.com>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/dedede/variants/baseboard/devicetree.cb

@@ -10,6 +10,10 @@ fw_config
 		option DB_PORTS_1C 7
 		option DB_PORTS_1A_HDMI_LTE 8
 	end
+	field STYLUS 4
+		option STYLUS_ABSENT 0
+		option STYLUS_PRESENT 1
+	end
         field TABLETMODE 10
                 option TABLETMODE_DISABLED 0
                 option TABLETMODE_ENABLED 1

src/mainboard/google/dedede/variants/magolor/Makefile.inc

@@ -1,3 +1,4 @@
 ## SPDX-License-Identifier: GPL-2.0-or-later
 
 ramstage-$(CONFIG_FW_CONFIG) += variant.c
+ramstage-y += gpio.c

src/mainboard/google/dedede/variants/magolor/gpio.c

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <baseboard/gpio.h>
+#include <baseboard/variants.h>
+#include <bootstate.h>
+#include <fw_config.h>
+#include <commonlib/helpers.h>
+
+/* Pad configuration of stylus */
+static const struct pad_config stylus_det_pads[] = {
+	/* C12 : AP_PEN_DET_ODL (external pull-high) */
+	PAD_CFG_GPI_GPIO_DRIVER(GPP_C12, NONE, DEEP),
+};
+
+static void fw_config_handle(void *unused)
+{
+	if (fw_config_probe(FW_CONFIG(STYLUS, STYLUS_PRESENT)))
+		gpio_configure_pads(stylus_det_pads, ARRAY_SIZE(stylus_det_pads));
+}
+BOOT_STATE_INIT_ENTRY(BS_DEV_ENABLE, BS_ON_ENTRY, fw_config_handle, NULL);

src/mainboard/google/dedede/variants/magolor/overridetree.cb

@@ -188,6 +188,19 @@ chip soc/intel/jasperlake
 			end
 		end # I2C 0
 		device pci 15.2 on
+			chip drivers/generic/gpio_keys
+				register "name" = ""PENH""
+				register "gpio" = "ACPI_GPIO_INPUT_ACTIVE_LOW(GPP_C12)"
+				register "key.wakeup_route" = "WAKEUP_ROUTE_GPIO_IRQ"
+				register "key.wakeup_event_action" = "EV_ACT_DEASSERTED"
+				register "key.dev_name" = ""EJCT""
+				register "key.linux_code" = "SW_PEN_INSERTED"
+				register "key.linux_input_type" = "EV_SW"
+				register "key.label" = ""pen_eject""
+				device generic 0 on
+					probe STYLUS STYLUS_PRESENT
+				end
+			end
 			chip drivers/i2c/hid
 				register "generic.hid" = ""ELAN6915""
 				register "generic.desc" = ""ELAN Touchscreen""