mei: gsc: retrieve the firmware version

Add a hook to retrieve the firmware version of the
GSC devices to bus-fixup.
GSC has a different MKHI clients GUIDs but the same message structure
to retrieve the firmware version as MEI so mei_fwver() can be reused.

CC: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220419193314.526966-6-daniele.ceraolospurio@intel.com

drivers/misc/mei/bus-fixup.c

@@ -30,6 +30,12 @@ static const uuid_le mei_nfc_info_guid = MEI_UUID_NFC_INFO;
 #define MEI_UUID_MKHIF_FIX UUID_LE(0x55213584, 0x9a29, 0x4916, \
 			0xba, 0xdf, 0xf, 0xb7, 0xed, 0x68, 0x2a, 0xeb)
 
+#define MEI_UUID_IGSC_MKHI UUID_LE(0xE2C2AFA2, 0x3817, 0x4D19, \
+			0x9D, 0x95, 0x06, 0xB1, 0x6B, 0x58, 0x8A, 0x5D)
+
+#define MEI_UUID_IGSC_MKHI_FIX UUID_LE(0x46E0C1FB, 0xA546, 0x414F, \
+			0x91, 0x70, 0xB7, 0xF4, 0x6D, 0x57, 0xB4, 0xAD)
+
 #define MEI_UUID_HDCP UUID_LE(0xB638AB7E, 0x94E2, 0x4EA2, \
 			      0xA5, 0x52, 0xD1, 0xC5, 0x4B, 0x62, 0x7F, 0x04)
 
@@ -241,6 +247,23 @@ static void mei_mkhi_fix(struct mei_cl_device *cldev)
 	mei_cldev_disable(cldev);
 }
 
+static void mei_gsc_mkhi_ver(struct mei_cl_device *cldev)
+{
+	int ret;
+
+	/* No need to enable the client if nothing is needed from it */
+	if (!cldev->bus->fw_f_fw_ver_supported)
+		return;
+
+	ret = mei_cldev_enable(cldev);
+	if (ret)
+		return;
+
+	ret = mei_fwver(cldev);
+	if (ret < 0)
+		dev_err(&cldev->dev, "FW version command failed %d\n", ret);
+	mei_cldev_disable(cldev);
+}
 /**
  * mei_wd - wd client on the bus, change protocol version
  *   as the API has changed.
@@ -492,6 +515,8 @@ static struct mei_fixup {
 	MEI_FIXUP(MEI_UUID_NFC_HCI, mei_nfc),
 	MEI_FIXUP(MEI_UUID_WD, mei_wd),
 	MEI_FIXUP(MEI_UUID_MKHIF_FIX, mei_mkhi_fix),
+	MEI_FIXUP(MEI_UUID_IGSC_MKHI, mei_gsc_mkhi_ver),
+	MEI_FIXUP(MEI_UUID_IGSC_MKHI_FIX, mei_gsc_mkhi_ver),
 	MEI_FIXUP(MEI_UUID_HDCP, whitelist),
 	MEI_FIXUP(MEI_UUID_ANY, vt_support),
 	MEI_FIXUP(MEI_UUID_PAVP, whitelist),

drivers/misc/mei/hw-me.c

@@ -1584,12 +1584,14 @@ static const struct mei_cfg mei_me_pch15_sps_cfg = {
 static const struct mei_cfg mei_me_gsc_cfg = {
 	MEI_CFG_TYPE_GSC,
 	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
 };
 
 /* Graphics System Controller Firmware Interface */
 static const struct mei_cfg mei_me_gscfi_cfg = {
 	MEI_CFG_TYPE_GSCFI,
 	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
 };
 
 /*