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authorVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>2016-10-07 15:41:39 +0300
committerWim Van Sebroeck <wim@iguana.be>2016-10-08 10:27:30 +0200
commit39487f6688a557ebfc69816d7e02f210bf8fb2a3 (patch)
tree225817aa47888bd3d16a2d54012eac326b1fb1ba /drivers/watchdog
parent2accf320786210db92f36866cc71fa894f510a4a (diff)
downloadlinux-39487f6688a557ebfc69816d7e02f210bf8fb2a3.tar.bz2
watchdog: imx2_wdt: add pretimeout function support
The change adds watchdog pretimeout notification handling to imx2_wdt driver, if device data contains information about a valid interrupt. It is unlikely but still possible (e.g. through a software limitation) that only a subset of watchdogs on SoC has interrupt lines, hence functionally the devices from these two groups have different capabilities, and this is reflected in different watchdog_info structs assigned to the devices. Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/imx2_wdt.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index d17643eb7683..4874b0f18650 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -24,6 +24,7 @@
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/init.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
@@ -50,6 +51,11 @@
#define IMX2_WDT_WRSR 0x04 /* Reset Status Register */
#define IMX2_WDT_WRSR_TOUT BIT(1) /* -> Reset due to Timeout */
+#define IMX2_WDT_WICR 0x06 /* Interrupt Control Register */
+#define IMX2_WDT_WICR_WIE BIT(15) /* -> Interrupt Enable */
+#define IMX2_WDT_WICR_WTIS BIT(14) /* -> Interrupt Status */
+#define IMX2_WDT_WICR_WICT 0xFF /* -> Interrupt Count Timeout */
+
#define IMX2_WDT_WMCR 0x08 /* Misc Register */
#define IMX2_WDT_MAX_TIME 128
@@ -80,6 +86,12 @@ static const struct watchdog_info imx2_wdt_info = {
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
};
+static const struct watchdog_info imx2_wdt_pretimeout_info = {
+ .identity = "imx2+ watchdog",
+ .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE |
+ WDIOF_PRETIMEOUT,
+};
+
static int imx2_wdt_restart(struct watchdog_device *wdog, unsigned long action,
void *data)
{
@@ -169,6 +181,35 @@ static int imx2_wdt_set_timeout(struct watchdog_device *wdog,
return 0;
}
+static int imx2_wdt_set_pretimeout(struct watchdog_device *wdog,
+ unsigned int new_pretimeout)
+{
+ struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
+
+ if (new_pretimeout >= IMX2_WDT_MAX_TIME)
+ return -EINVAL;
+
+ wdog->pretimeout = new_pretimeout;
+
+ regmap_update_bits(wdev->regmap, IMX2_WDT_WICR,
+ IMX2_WDT_WICR_WIE | IMX2_WDT_WICR_WICT,
+ IMX2_WDT_WICR_WIE | (new_pretimeout << 1));
+ return 0;
+}
+
+static irqreturn_t imx2_wdt_isr(int irq, void *wdog_arg)
+{
+ struct watchdog_device *wdog = wdog_arg;
+ struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
+
+ regmap_write_bits(wdev->regmap, IMX2_WDT_WICR,
+ IMX2_WDT_WICR_WTIS, IMX2_WDT_WICR_WTIS);
+
+ watchdog_notify_pretimeout(wdog);
+
+ return IRQ_HANDLED;
+}
+
static int imx2_wdt_start(struct watchdog_device *wdog)
{
struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
@@ -188,6 +229,7 @@ static const struct watchdog_ops imx2_wdt_ops = {
.start = imx2_wdt_start,
.ping = imx2_wdt_ping,
.set_timeout = imx2_wdt_set_timeout,
+ .set_pretimeout = imx2_wdt_set_pretimeout,
.restart = imx2_wdt_restart,
};
@@ -236,6 +278,12 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
wdog->max_hw_heartbeat_ms = IMX2_WDT_MAX_TIME * 1000;
wdog->parent = &pdev->dev;
+ ret = platform_get_irq(pdev, 0);
+ if (ret > 0)
+ if (!devm_request_irq(&pdev->dev, ret, imx2_wdt_isr, 0,
+ dev_name(&pdev->dev), wdog))
+ wdog->info = &imx2_wdt_pretimeout_info;
+
ret = clk_prepare_enable(wdev->clk);
if (ret)
return ret;