mb/google/myst: Enable USB WWAN

Add usb wwan device tree entry. Also set wwan_rst to high due to
HW design active high.

BUG=b:285792436
TEST=check FM101 is detected by Linux kernel.
Bus 002 Device 002: ID 2cb7:01a2 Fibocom Wireless Inc.

Signed-off-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Change-Id: I0aa60cb284d4b7f99e16643a92ee58467a355026
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75660
Reviewed-by: Tim Van Patten <timvp@google.com>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Reviewed-by: Martin Roth <martin.roth@amd.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

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

@@ -293,6 +293,25 @@ chip soc/amd/phoenix
 					end
 				end
 			end
+			device ref xhci_1 on
+				chip drivers/usb/acpi
+					register "type" = "UPC_TYPE_HUB"
+					device ref xhci_1_root_hub on
+						chip drivers/usb/acpi
+							register "desc" = ""USB3 WWAN""
+							register "type" = "UPC_TYPE_INTERNAL"
+							register "has_power_resource" = "1"
+							register "enable_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_HIGH(GPIO_6)"
+							register "enable_delay_ms" = "20"
+							register "reset_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_HIGH(GPIO_11)"
+							register "reset_off_delay_ms" = "20"
+							device ref usb3_port7 on
+								probe WWAN WWAN_FM101GL
+							end
+						end
+					end
+				end
+			end
 			device ref acp on end # Audio Processor (ACP)
 			device ref mp2 on end # Sensor Fusion Hub (MP2)
 		end

src/mainboard/google/myst/variants/baseboard/gpio.c

@@ -28,7 +28,7 @@ static const struct soc_amd_gpio base_gpio_table[] = {
 	/* EN_PP3300_WLAN */
 	PAD_GPO(GPIO_9, HIGH),
 	/* WWAN_RST */
-	PAD_GPO(GPIO_11, LOW),
+	PAD_GPO(GPIO_11, HIGH),
 	/* Unused */
 	PAD_NC(GPIO_12),
 	/* GPIO_13 - GPIO_15: Not available */