[linux-yocto] [PATCH 7/9] watchdog: iTCO_wdt: Add support for TCO on Intel Sunrisepoint

[Tan Jui Nee]

From: Matt Fleming <matt.fleming at intel.com>

The revision of the watchdog hardware in Sunrisepoint necessitates a new
"version" inside the TCO watchdog driver because some of the register
layouts have changed.

Also update the Kconfig entry to select both the LPC and SMBus drivers
since the TCO device is on the SMBus in Sunrisepoint.

Signed-off-by: Matt Fleming <matt.fleming at intel.com>
Reviewed-by: Guenter Roeck <linux at roeck-us.net>
Signed-off-by: Lee Jones <lee.jones at linaro.org>
(cherry picked from commit 2a7a0e9bf7b32e838d873226808ab8a6c00148f7)
Signed-off-by: Tan Jui Nee <jui.nee.tan at intel.com>
---
 drivers/watchdog/Kconfig    |  3 +-
 drivers/watchdog/iTCO_wdt.c | 71 ++++++++++++++++++++++++++++-----------------
 2 files changed, 46 insertions(+), 28 deletions(-)

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index e5e7c55..020fb8a 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -753,7 +753,8 @@ config ITCO_WDT
 	tristate "Intel TCO Timer/Watchdog"
 	depends on (X86 || IA64) && PCI
 	select WATCHDOG_CORE
-	select LPC_ICH
+	select LPC_ICH if !EXPERT
+	select I2C_I801 if !EXPERT
 	---help---
 	  Hardware driver for the intel TCO timer based watchdog devices.
 	  These drivers are included in the Intel 82801 I/O Controller
diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index a94401b..0acc6c5 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -145,59 +145,67 @@ static inline unsigned int ticks_to_seconds(int ticks)
 	return iTCO_wdt_private.iTCO_version == 3 ? ticks : (ticks * 6) / 10;
 }
 
+static inline u32 no_reboot_bit(void)
+{
+	u32 enable_bit;
+
+	switch (iTCO_wdt_private.iTCO_version) {
+	case 3:
+		enable_bit = 0x00000010;
+		break;
+	case 2:
+		enable_bit = 0x00000020;
+		break;
+	case 4:
+	case 1:
+	default:
+		enable_bit = 0x00000002;
+		break;
+	}
+
+	return enable_bit;
+}
+
 static void iTCO_wdt_set_NO_REBOOT_bit(void)
 {
 	u32 val32;
 
 	/* Set the NO_REBOOT bit: this disables reboots */
-	if (iTCO_wdt_private.iTCO_version == 3) {
-		val32 = readl(iTCO_wdt_private.gcs_pmc);
-		val32 |= 0x00000010;
-		writel(val32, iTCO_wdt_private.gcs_pmc);
-	} else if (iTCO_wdt_private.iTCO_version == 2) {
+	if (iTCO_wdt_private.iTCO_version >= 2) {
 		val32 = readl(iTCO_wdt_private.gcs_pmc);
-		val32 |= 0x00000020;
+		val32 |= no_reboot_bit();
 		writel(val32, iTCO_wdt_private.gcs_pmc);
 	} else if (iTCO_wdt_private.iTCO_version == 1) {
 		pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
-		val32 |= 0x00000002;
+		val32 |= no_reboot_bit();
 		pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
 	}
 }
 
 static int iTCO_wdt_unset_NO_REBOOT_bit(void)
 {
-	int ret = 0;
-	u32 val32;
+	u32 enable_bit = no_reboot_bit();
+	u32 val32 = 0;
 
 	/* Unset the NO_REBOOT bit: this enables reboots */
-	if (iTCO_wdt_private.iTCO_version == 3) {
-		val32 = readl(iTCO_wdt_private.gcs_pmc);
-		val32 &= 0xffffffef;
-		writel(val32, iTCO_wdt_private.gcs_pmc);
-
-		val32 = readl(iTCO_wdt_private.gcs_pmc);
-		if (val32 & 0x00000010)
-			ret = -EIO;
-	} else if (iTCO_wdt_private.iTCO_version == 2) {
+	if (iTCO_wdt_private.iTCO_version >= 2) {
 		val32 = readl(iTCO_wdt_private.gcs_pmc);
-		val32 &= 0xffffffdf;
+		val32 &= ~enable_bit;
 		writel(val32, iTCO_wdt_private.gcs_pmc);
 
 		val32 = readl(iTCO_wdt_private.gcs_pmc);
-		if (val32 & 0x00000020)
-			ret = -EIO;
 	} else if (iTCO_wdt_private.iTCO_version == 1) {
 		pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
-		val32 &= 0xfffffffd;
+		val32 &= ~enable_bit;
 		pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
 
 		pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
-		if (val32 & 0x00000002)
-			ret = -EIO;
 	}
 
-	return ret; /* returns: 0 = OK, -EIO = Error */
+	if (val32 & enable_bit)
+		return -EIO;
+
+	return 0;
 }
 
 static int iTCO_wdt_start(struct watchdog_device *wd_dev)
@@ -503,12 +511,21 @@ static int iTCO_wdt_probe(struct platform_device *dev)
 		pdata->name, pdata->version, (u64)TCOBASE);
 
 	/* Clear out the (probably old) status */
-	if (iTCO_wdt_private.iTCO_version == 3) {
+	switch (iTCO_wdt_private.iTCO_version) {
+	case 4:
+		outw(0x0008, TCO1_STS);	/* Clear the Time Out Status bit */
+		outw(0x0002, TCO2_STS);	/* Clear SECOND_TO_STS bit */
+		break;
+	case 3:
 		outl(0x20008, TCO1_STS);
-	} else {
+		break;
+	case 2:
+	case 1:
+	default:
 		outw(0x0008, TCO1_STS);	/* Clear the Time Out Status bit */
 		outw(0x0002, TCO2_STS);	/* Clear SECOND_TO_STS bit */
 		outw(0x0004, TCO2_STS);	/* Clear BOOT_STS bit */
+		break;
 	}
 
 	iTCO_wdt_watchdog_dev.bootstatus = 0;
-- 
1.9.1