mei: me: disable driver on the ign firmware

Add a quirk to disable MEI interface on Intel PCH Ignition (IGN)
as the IGN firmware doesn't support the protocol.

Cc: <stable@vger.kernel.org>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20220215080438.264876-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/hw-me-regs.h

@@ -120,6 +120,7 @@
 #define PCI_CFG_HFS_2         0x48
 #define PCI_CFG_HFS_3         0x60
 #  define PCI_CFG_HFS_3_FW_SKU_MSK   0x00000070
+#  define PCI_CFG_HFS_3_FW_SKU_IGN   0x00000000
 #  define PCI_CFG_HFS_3_FW_SKU_SPS   0x00000060
 #define PCI_CFG_HFS_4         0x64
 #define PCI_CFG_HFS_5         0x68

drivers/misc/mei/hw-me.c

@@ -1405,16 +1405,16 @@ static bool mei_me_fw_type_sps_4(const struct pci_dev *pdev)
 	.quirk_probe = mei_me_fw_type_sps_4
 
 /**
- * mei_me_fw_type_sps() - check for sps sku
+ * mei_me_fw_type_sps_ign() - check for sps or ign sku
  *
- * Read ME FW Status register to check for SPS Firmware.
- * The SPS FW is only signaled in pci function 0
+ * Read ME FW Status register to check for SPS or IGN Firmware.
+ * The SPS/IGN FW is only signaled in pci function 0
  *
  * @pdev: pci device
  *
- * Return: true in case of SPS firmware
+ * Return: true in case of SPS/IGN firmware
  */
-static bool mei_me_fw_type_sps(const struct pci_dev *pdev)
+static bool mei_me_fw_type_sps_ign(const struct pci_dev *pdev)
 {
 	u32 reg;
 	u32 fw_type;
@@ -1427,14 +1427,15 @@ static bool mei_me_fw_type_sps(const struct pci_dev *pdev)
 
 	dev_dbg(&pdev->dev, "fw type is %d\n", fw_type);
 
-	return fw_type == PCI_CFG_HFS_3_FW_SKU_SPS;
+	return fw_type == PCI_CFG_HFS_3_FW_SKU_IGN ||
+	       fw_type == PCI_CFG_HFS_3_FW_SKU_SPS;
 }
 
 #define MEI_CFG_KIND_ITOUCH                     \
 	.kind = "itouch"
 
-#define MEI_CFG_FW_SPS                          \
-	.quirk_probe = mei_me_fw_type_sps
+#define MEI_CFG_FW_SPS_IGN                      \
+	.quirk_probe = mei_me_fw_type_sps_ign
 
 #define MEI_CFG_FW_VER_SUPP                     \
 	.fw_ver_supported = 1
@@ -1535,7 +1536,7 @@ static const struct mei_cfg mei_me_pch12_sps_cfg = {
 	MEI_CFG_PCH8_HFS,
 	MEI_CFG_FW_VER_SUPP,
 	MEI_CFG_DMA_128,
-	MEI_CFG_FW_SPS,
+	MEI_CFG_FW_SPS_IGN,
 };
 
 /* Cannon Lake itouch with quirk for SPS 5.0 and newer Firmware exclusion
@@ -1545,7 +1546,7 @@ static const struct mei_cfg mei_me_pch12_itouch_sps_cfg = {
 	MEI_CFG_KIND_ITOUCH,
 	MEI_CFG_PCH8_HFS,
 	MEI_CFG_FW_VER_SUPP,
-	MEI_CFG_FW_SPS,
+	MEI_CFG_FW_SPS_IGN,
 };
 
 /* Tiger Lake and newer devices */
@@ -1562,7 +1563,7 @@ static const struct mei_cfg mei_me_pch15_sps_cfg = {
 	MEI_CFG_FW_VER_SUPP,
 	MEI_CFG_DMA_128,
 	MEI_CFG_TRC,
-	MEI_CFG_FW_SPS,
+	MEI_CFG_FW_SPS_IGN,
 };
 
 /*