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@xxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Reviewed-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
Changes from v5 to v6:
* no changes but added reviewed-by tags given by Guenter and Wolfram for v5
* I'm not sure if Wolfram had a chance to test the change on some i.MX
platform, thus I don't add his tested-by tag to this commit.
In v5 this was a new change.
drivers/watchdog/imx2_wdt.c | 48 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
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;
--
2.8.1
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