linux-kernel - [char-misc-next 3/7] mei: me: make mei_me_fw_sku_sps

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Date:   Fri, 19 Jun 2020 19:51:17 +0300
From:   Tomas Winkler <tomas.winkler@...el.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:     Alexander Usyskin <alexander.usyskin@...el.com>,
        linux-kernel@...r.kernel.org,
        Tomas Winkler <tomas.winkler@...el.com>
Subject: [char-misc-next 3/7] mei: me: make mei_me_fw_sku_sps_4() less cryptic

Last add mei_me_fw_sku_sps_4() kdoc and add descriptive defines
for register name and values.

Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
---
 drivers/misc/mei/hw-me-regs.h |  2 ++
 drivers/misc/mei/hw-me.c      | 18 ++++++++++++------
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/misc/mei/hw-me-regs.h b/drivers/misc/mei/hw-me-regs.h
index 01b1bf74f262..64823bdde6af 100644
--- a/drivers/misc/mei/hw-me-regs.h
+++ b/drivers/misc/mei/hw-me-regs.h
@@ -105,6 +105,8 @@
 /* Host Firmware Status Registers in PCI Config Space */
 #define PCI_CFG_HFS_1         0x40
 #  define PCI_CFG_HFS_1_D0I3_MSK     0x80000000
+#  define PCI_CFG_HFS_1_OPMODE_MSK 0xf0000 /* OP MODE Mask: SPS <= 4.0 */
+#  define PCI_CFG_HFS_1_OPMODE_SPS 0xf0000 /* SPS SKU : SPS <= 4.0 */
 #define PCI_CFG_HFS_2         0x48
 #define PCI_CFG_HFS_3         0x60
 #  define PCI_CFG_HFS_3_FW_SKU_MSK   0x00000070
diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index b45143510912..6aa522c0d910 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -1366,20 +1366,26 @@ static bool mei_me_fw_type_nm(const struct pci_dev *pdev)
 #define MEI_CFG_FW_NM                           \
 	.quirk_probe = mei_me_fw_type_nm
 
+/**
+ * mei_me_fw_sku_sps_4() - check for sps 4.0 sku
+ *
+ * Read ME FW Status register to check for SPS Firmware.
+ * The SPS FW is only signaled in the PCI function 0.
+ * __Note__: Deprecated by SPS 5.0 and newer.
+ *
+ * @pdev: pci device
+ *
+ * Return: true in case of SPS firmware
+ */
 static bool mei_me_fw_type_sps_4(const struct pci_dev *pdev)
 {
 	u32 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;
+	return (reg & PCI_CFG_HFS_1_OPMODE_MSK) == PCI_CFG_HFS_1_OPMODE_SPS;
 }
 
 #define MEI_CFG_FW_SPS_4                          \
-- 
2.25.4