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>
This commit is contained in:
Vladimir Zapolskiy 2016-10-07 15:41:39 +03:00 committed by Wim Van Sebroeck
parent 2accf32078
commit 39487f6688

View file

@ -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;