linux-kernel - [PATCH v5 4/6] watchdog: iTCO_wdt: cleanup set/unset no

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Date:   Mon,  3 Apr 2017 17:24:32 -0700
From:   Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@...ux.intel.com>
To:     andy@...radead.org, qipeng.zha@...el.com, dvhart@...radead.org,
        linux@...ck-us.net
Cc:     wim@...ana.be, sathyaosid@...il.com, david.e.box@...ux.intel.com,
        rajneesh.bhardwaj@...el.com,
        sathyanarayanan.kuppuswamy@...ux.intel.com,
        platform-driver-x86@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-watchdog@...r.kernel.org
Subject: [PATCH v5 4/6] watchdog: iTCO_wdt: cleanup set/unset no_reboot calls

Both iTCO_wdt_unset_NO_REBOOT_bit() and iTCO_wdt_unset_NO_REBOOT_bit()
functions has lot of common code between them. So merging these two
functions would remove these unnecessary code duplications. This patch
fixes this issue by creating single update function to handle both
set/unset functionalities.

Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@...ux.intel.com>
---
 drivers/watchdog/iTCO_wdt.c | 53 ++++++++++++++++-----------------------------
 1 file changed, 19 insertions(+), 34 deletions(-)

diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index 521ae95..cddfa00 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -172,50 +172,35 @@ static inline u32 no_reboot_bit(struct iTCO_wdt_private *p)
 	return enable_bit;
 }
 
-static void iTCO_wdt_set_NO_REBOOT_bit(struct iTCO_wdt_private *p)
+static int iTCO_wdt_update_no_reboot_flag(struct iTCO_wdt_private *p,
+					  bool status)
 {
-	u32 val32;
+	u32 val32 = 0, newval32 = 0;
 
-	/* Set the NO_REBOOT bit: this disables reboots */
 	if (p->iTCO_version >= 2) {
 		if (p->update_noreboot_flag)
-			p->update_noreboot_flag(true);
+			return p->update_noreboot_flag(status);
 		else {
 			val32 = readl(p->gcs_pmc);
-			val32 |= no_reboot_bit(p);
-			writel(val32, p->gcs_pmc);
-		}
-	} else if (p->iTCO_version == 1) {
-		pci_read_config_dword(p->pci_dev, 0xd4, &val32);
-		val32 |= no_reboot_bit(p);
-		pci_write_config_dword(p->pci_dev, 0xd4, val32);
-	}
-}
-
-static int iTCO_wdt_unset_NO_REBOOT_bit(struct iTCO_wdt_private *p)
-{
-	u32 enable_bit = no_reboot_bit(p);
-	u32 val32 = 0;
+			if (status)
+				val32 |= no_reboot_bit(p);
+			else
+				val32 &= ~no_reboot_bit(p);
 
-	/* Unset the NO_REBOOT bit: this enables reboots */
-	if (p->iTCO_version >= 2) {
-		if (p->update_noreboot_flag)
-			return p->update_noreboot_flag(false);
-		else {
-			val32 = readl(p->gcs_pmc);
-			val32 &= ~enable_bit;
 			writel(val32, p->gcs_pmc);
-			val32 = readl(p->gcs_pmc);
+			newval32 = readl(p->gcs_pmc);
 		}
 	} else if (p->iTCO_version == 1) {
 		pci_read_config_dword(p->pci_dev, 0xd4, &val32);
-		val32 &= ~enable_bit;
+		if (status)
+			val32 |= no_reboot_bit(p);
+		else
+			val32 &= ~no_reboot_bit(p);
 		pci_write_config_dword(p->pci_dev, 0xd4, val32);
-
-		pci_read_config_dword(p->pci_dev, 0xd4, &val32);
+		pci_read_config_dword(p->pci_dev, 0xd4, &newval32);
 	}
 
-	if (val32 & enable_bit)
+	if (val32 != newval32)
 		return -EIO;
 
 	return 0;
@@ -231,7 +216,7 @@ static int iTCO_wdt_start(struct watchdog_device *wd_dev)
 	iTCO_vendor_pre_start(p->smi_res, wd_dev->timeout);
 
 	/* disable chipset's NO_REBOOT bit */
-	if (iTCO_wdt_unset_NO_REBOOT_bit(p)) {
+	if (iTCO_wdt_update_no_reboot_flag(p, false)) {
 		spin_unlock(&p->io_lock);
 		pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n");
 		return -EIO;
@@ -272,7 +257,7 @@ static int iTCO_wdt_stop(struct watchdog_device *wd_dev)
 	val = inw(TCO1_CNT(p));
 
 	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
-	iTCO_wdt_set_NO_REBOOT_bit(p);
+	iTCO_wdt_update_no_reboot_flag(p, true);
 
 	spin_unlock(&p->io_lock);
 
@@ -452,14 +437,14 @@ static int iTCO_wdt_probe(struct platform_device *pdev)
 	}
 
 	/* Check chipset's NO_REBOOT bit */
-	if (iTCO_wdt_unset_NO_REBOOT_bit(p) &&
+	if (iTCO_wdt_update_no_reboot_flag(p, false) &&
 	    iTCO_vendor_check_noreboot_on()) {
 		pr_info("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
 		return -ENODEV;	/* Cannot reset NO_REBOOT bit */
 	}
 
 	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
-	iTCO_wdt_set_NO_REBOOT_bit(p);
+	iTCO_wdt_update_no_reboot_flag(p, true);
 
 	/* The TCO logic uses the TCO_EN bit in the SMI_EN register */
 	if (!devm_request_region(dev, p->smi_res->start,
-- 
2.7.4