[char-misc v2] mei: me: disable driver on SPT SPS firmware

[Tomas Winkler]

Sunrise Point PCH with SPS Firmware doesn't expose working
MEI interface, we need to quirk it out.
The SPS Firmware is identifiable only on the first PCI function
of the device.

Cc: <stable@xxxxxxxxxxxxxxx> #4.6+
Tested-by: Sujith Pandel <sujith_pandel@xxxxxxxx>
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
---
V2: 1. disable also second mei device
    2. The SPS Firmware is identifiable only on the first PCI function
       of the device.
    3. Doesn't apply cleanly on < v4.6, I will sent a new rebased patch
       for the older kernels
 drivers/misc/mei/hw-me.c  | 10 ++++++++--
 drivers/misc/mei/pci-me.c |  4 ++--
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index c2d70d2dd112..56c2101e80ad 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -1266,8 +1266,14 @@ static bool mei_me_fw_type_nm(struct pci_dev *pdev)
 static bool mei_me_fw_type_sps(struct pci_dev *pdev)
 {
 	u32 reg;
-	/* Read ME FW Status check for SPS Firmware */
-	pci_read_config_dword(pdev, PCI_CFG_HFS_1, &reg);
+	unsigned int devfn;
+
+	/*
+	 * Read ME FW Status register to check for SPS Firmware
+	 * The SPS FW is only signaled in pci function 0
+	 */
+	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
+	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_1, &reg);
 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
 	/* if bits [19:16] = 15, running SPS Firmware */
 	return (reg & 0xf0000) == 0xf0000;
diff --git a/drivers/misc/mei/pci-me.c b/drivers/misc/mei/pci-me.c
index 718addfa9fb0..031e7c92fcc7 100644
--- a/drivers/misc/mei/pci-me.c
+++ b/drivers/misc/mei/pci-me.c
@@ -85,8 +85,8 @@ static const struct pci_device_id mei_me_pci_tbl[] = {
 
 	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT, mei_me_pch8_cfg)},
 	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_2, mei_me_pch8_cfg)},
-	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_H, mei_me_pch8_cfg)},
-	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_H_2, mei_me_pch8_cfg)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_H, mei_me_pch8_sps_cfg)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_H_2, mei_me_pch8_sps_cfg)},
 
 	{MEI_PCI_DEVICE(MEI_DEV_ID_BXT_M, mei_me_pch8_cfg)},
 	{MEI_PCI_DEVICE(MEI_DEV_ID_APL_I, mei_me_pch8_cfg)},
-- 
2.5.5