[S] Change in coreboot[master]: mb/google/dedede/variants/shotzo: Turn off LAN power in S0ix

[Tony Huang (Code Review)]

Tony Huang has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/67528 )

Change subject: mb/google/dedede/variants/shotzo: Turn off LAN power in S0ix
......................................................................

mb/google/dedede/variants/shotzo: Turn off LAN power in S0ix

Turn off the LAN power which is controlled by GPP_A10 in S0ix states.
For an USB device, the S0ix hook is needed for the on/off operationas
to take place.

BUG=b:245426120
BRANCH=firmware-dedede-13606.B
TEST=emerge-shotzo coreboot
     check LAN LED off in S0ix states
     check LAN function ok after suspending 500 loops
     check SSDT table has MS0X entry
     Scope (_SB)
    {
        Method (MS0X, 1, Serialized)
        {
            If ((Arg0 == One))
            {
                _SB.PCI0.CTXS (0x41)
            }
            Else
            {
                _SB.PCI0.STXS (0x41)
            }
        }
    }

Change-Id: I3fcab4a73239b4f006839c0c81e9b4cc74047b77
Signed-off-by: Tony Huang 
---
M src/mainboard/google/dedede/variants/shotzo/Makefile.inc
A src/mainboard/google/dedede/variants/shotzo/variant.c
2 files changed, 49 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/28/67528/1

diff --git a/src/mainboard/google/dedede/variants/shotzo/Makefile.inc b/src/mainboard/google/dedede/variants/shotzo/Makefile.inc
index eb2c9bc..655f3c8 100644
--- a/src/mainboard/google/dedede/variants/shotzo/Makefile.inc
+++ b/src/mainboard/google/dedede/variants/shotzo/Makefile.inc
@@ -1,3 +1,4 @@
 ## SPDX-License-Identifier: GPL-2.0-or-later

ramstage-y += gpio.c
+ramstage-y += variant.c
diff --git a/src/mainboard/google/dedede/variants/shotzo/variant.c b/src/mainboard/google/dedede/variants/shotzo/variant.c
new file mode 100644
index 0000000..98d4fb1
--- /dev/null
+++ b/src/mainboard/google/dedede/variants/shotzo/variant.c
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <baseboard/variants.h>
+#include <variant/gpio.h>
+#include <acpi/acpigen.h>
+
+void variant_generate_s0ix_hook(enum s0ix_entry entry)
+{
+	if (entry == S0IX_ENTRY)
+		acpigen_soc_clear_tx_gpio(GPP_A10);
+	else if (entry == S0IX_EXIT)
+		acpigen_soc_set_tx_gpio(GPP_A10);
+}