| Message ID | 20221103100358.176099-2-andrej.picej@norik.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Suspending i.MX watchdog in WAIT mode | expand |
On Thu, Nov 03, 2022 at 11:03:56AM +0100, Andrej Picej wrote: > Putting device into the "Suspend-To-Idle" mode causes watchdog to > trigger and resets the board after set watchdog timeout period elapses. > > Introduce new device-tree property "fsl,suspend-in-wait" which suspends > watchdog in WAIT mode. This is done by setting WDW bit in WCR > (Watchdog Control Register). Watchdog operation is restored after > exiting WAIT mode as expected. WAIT mode corresponds with Linux's > "Suspend-To-Idle". > > Signed-off-by: Andrej Picej <andrej.picej@norik.com> > Reviewed-by: Fabio Estevam <festevam@gmail.com> For my reference: Reviewed-by: Guenter Roeck <linux@roeck-us.net> This will have to wait for dt approval. Thanks, Guenter > --- > Changes in v3: > - fix spelling in commit message, > - fix and simplify property handling in probe, > - add a comment about unknown interaction between imx7d no-ping > functionality and "fsl,suspend-in-wait", > - property support handled by of_device_id data pointer. > > Changes in v2: > - validate the property with compatible string, as this functionality > is not supported by all devices. > --- > drivers/watchdog/imx2_wdt.c | 55 +++++++++++++++++++++++++++++++++++-- > 1 file changed, 52 insertions(+), 3 deletions(-) > > diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c > index d0c5d47ddede..19ab7b3d286b 100644 > --- a/drivers/watchdog/imx2_wdt.c > +++ b/drivers/watchdog/imx2_wdt.c > @@ -27,6 +27,7 @@ > #include <linux/module.h> > #include <linux/moduleparam.h> > #include <linux/of_address.h> > +#include <linux/of_device.h> > #include <linux/platform_device.h> > #include <linux/regmap.h> > #include <linux/watchdog.h> > @@ -35,6 +36,7 @@ > > #define IMX2_WDT_WCR 0x00 /* Control Register */ > #define IMX2_WDT_WCR_WT (0xFF << 8) /* -> Watchdog Timeout Field */ > +#define IMX2_WDT_WCR_WDW BIT(7) /* -> Watchdog disable for WAIT */ > #define IMX2_WDT_WCR_WDA BIT(5) /* -> External Reset WDOG_B */ > #define IMX2_WDT_WCR_SRS BIT(4) /* -> Software Reset Signal */ > #define IMX2_WDT_WCR_WRE BIT(3) /* -> WDOG Reset Enable */ > @@ -60,13 +62,19 @@ > > #define WDOG_SEC_TO_COUNT(s) ((s * 2 - 1) << 8) > > +struct imx2_wdt_data { > + bool wdw_supported; > +}; > + > struct imx2_wdt_device { > struct clk *clk; > struct regmap *regmap; > struct watchdog_device wdog; > + const struct imx2_wdt_data *data; > bool ext_reset; > bool clk_is_on; > bool no_ping; > + bool sleep_wait; > }; > > static bool nowayout = WATCHDOG_NOWAYOUT; > @@ -129,6 +137,9 @@ static inline void imx2_wdt_setup(struct watchdog_device *wdog) > > /* Suspend timer in low power mode, write once-only */ > val |= IMX2_WDT_WCR_WDZST; > + /* Suspend timer in low power WAIT mode, write once-only */ > + if (wdev->sleep_wait) > + val |= IMX2_WDT_WCR_WDW; > /* Strip the old watchdog Time-Out value */ > val &= ~IMX2_WDT_WCR_WT; > /* Generate internal chip-level reset if WDOG times out */ > @@ -292,6 +303,8 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) > wdog->max_hw_heartbeat_ms = IMX2_WDT_MAX_TIME * 1000; > wdog->parent = dev; > > + wdev->data = of_device_get_match_data(dev); > + > ret = platform_get_irq(pdev, 0); > if (ret > 0) > if (!devm_request_irq(dev, ret, imx2_wdt_isr, 0, > @@ -313,9 +326,18 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) > > wdev->ext_reset = of_property_read_bool(dev->of_node, > "fsl,ext-reset-output"); > + > + if (of_property_read_bool(dev->of_node, "fsl,suspend-in-wait")) { > + if (!wdev->data->wdw_supported) { > + dev_err(dev, "suspend-in-wait not supported\n"); > + return -EINVAL; > + } > + wdev->sleep_wait = true; > + } > + > /* > * The i.MX7D doesn't support low power mode, so we need to ping the watchdog > - * during suspend. > + * during suspend. Interaction with "fsl,suspend-in-wait" is unknown! > */ > wdev->no_ping = !of_device_is_compatible(dev->of_node, "fsl,imx7d-wdt"); > platform_set_drvdata(pdev, wdog); > @@ -417,9 +439,36 @@ static int __maybe_unused imx2_wdt_resume(struct device *dev) > static SIMPLE_DEV_PM_OPS(imx2_wdt_pm_ops, imx2_wdt_suspend, > imx2_wdt_resume); > > +struct imx2_wdt_data imx_wdt = { > + .wdw_supported = true, > +}; > + > +struct imx2_wdt_data imx_wdt_legacy = { > + .wdw_supported = false, > +}; > + > static const struct of_device_id imx2_wdt_dt_ids[] = { > - { .compatible = "fsl,imx21-wdt", }, > - { .compatible = "fsl,imx7d-wdt", }, > + { .compatible = "fsl,imx21-wdt", .data = &imx_wdt_legacy }, > + { .compatible = "fsl,imx25-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx27-wdt", .data = &imx_wdt_legacy }, > + { .compatible = "fsl,imx31-wdt", .data = &imx_wdt_legacy }, > + { .compatible = "fsl,imx35-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx50-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx51-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx53-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx6q-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx6sl-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx6sll-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx6sx-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx6ul-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx7d-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx8mm-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx8mn-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx8mp-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,imx8mq-wdt", .data = &imx_wdt }, > + { .compatible = "fsl,ls1012a-wdt", .data = &imx_wdt_legacy }, > + { .compatible = "fsl,ls1043a-wdt", .data = &imx_wdt_legacy }, > + { .compatible = "fsl,vf610-wdt", .data = &imx_wdt }, > { /* sentinel */ } > }; > MODULE_DEVICE_TABLE(of, imx2_wdt_dt_ids); > -- > 2.25.1 >
diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c index d0c5d47ddede..19ab7b3d286b 100644 --- a/drivers/watchdog/imx2_wdt.c +++ b/drivers/watchdog/imx2_wdt.c @@ -27,6 +27,7 @@ #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/of_address.h> +#include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/regmap.h> #include <linux/watchdog.h> @@ -35,6 +36,7 @@ #define IMX2_WDT_WCR 0x00 /* Control Register */ #define IMX2_WDT_WCR_WT (0xFF << 8) /* -> Watchdog Timeout Field */ +#define IMX2_WDT_WCR_WDW BIT(7) /* -> Watchdog disable for WAIT */ #define IMX2_WDT_WCR_WDA BIT(5) /* -> External Reset WDOG_B */ #define IMX2_WDT_WCR_SRS BIT(4) /* -> Software Reset Signal */ #define IMX2_WDT_WCR_WRE BIT(3) /* -> WDOG Reset Enable */ @@ -60,13 +62,19 @@ #define WDOG_SEC_TO_COUNT(s) ((s * 2 - 1) << 8) +struct imx2_wdt_data { + bool wdw_supported; +}; + struct imx2_wdt_device { struct clk *clk; struct regmap *regmap; struct watchdog_device wdog; + const struct imx2_wdt_data *data; bool ext_reset; bool clk_is_on; bool no_ping; + bool sleep_wait; }; static bool nowayout = WATCHDOG_NOWAYOUT; @@ -129,6 +137,9 @@ static inline void imx2_wdt_setup(struct watchdog_device *wdog) /* Suspend timer in low power mode, write once-only */ val |= IMX2_WDT_WCR_WDZST; + /* Suspend timer in low power WAIT mode, write once-only */ + if (wdev->sleep_wait) + val |= IMX2_WDT_WCR_WDW; /* Strip the old watchdog Time-Out value */ val &= ~IMX2_WDT_WCR_WT; /* Generate internal chip-level reset if WDOG times out */ @@ -292,6 +303,8 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) wdog->max_hw_heartbeat_ms = IMX2_WDT_MAX_TIME * 1000; wdog->parent = dev; + wdev->data = of_device_get_match_data(dev); + ret = platform_get_irq(pdev, 0); if (ret > 0) if (!devm_request_irq(dev, ret, imx2_wdt_isr, 0, @@ -313,9 +326,18 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) wdev->ext_reset = of_property_read_bool(dev->of_node, "fsl,ext-reset-output"); + + if (of_property_read_bool(dev->of_node, "fsl,suspend-in-wait")) { + if (!wdev->data->wdw_supported) { + dev_err(dev, "suspend-in-wait not supported\n"); + return -EINVAL; + } + wdev->sleep_wait = true; + } + /* * The i.MX7D doesn't support low power mode, so we need to ping the watchdog - * during suspend. + * during suspend. Interaction with "fsl,suspend-in-wait" is unknown! */ wdev->no_ping = !of_device_is_compatible(dev->of_node, "fsl,imx7d-wdt"); platform_set_drvdata(pdev, wdog); @@ -417,9 +439,36 @@ static int __maybe_unused imx2_wdt_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(imx2_wdt_pm_ops, imx2_wdt_suspend, imx2_wdt_resume); +struct imx2_wdt_data imx_wdt = { + .wdw_supported = true, +}; + +struct imx2_wdt_data imx_wdt_legacy = { + .wdw_supported = false, +}; + static const struct of_device_id imx2_wdt_dt_ids[] = { - { .compatible = "fsl,imx21-wdt", }, - { .compatible = "fsl,imx7d-wdt", }, + { .compatible = "fsl,imx21-wdt", .data = &imx_wdt_legacy }, + { .compatible = "fsl,imx25-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx27-wdt", .data = &imx_wdt_legacy }, + { .compatible = "fsl,imx31-wdt", .data = &imx_wdt_legacy }, + { .compatible = "fsl,imx35-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx50-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx51-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx53-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx6q-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx6sl-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx6sll-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx6sx-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx6ul-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx7d-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx8mm-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx8mn-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx8mp-wdt", .data = &imx_wdt }, + { .compatible = "fsl,imx8mq-wdt", .data = &imx_wdt }, + { .compatible = "fsl,ls1012a-wdt", .data = &imx_wdt_legacy }, + { .compatible = "fsl,ls1043a-wdt", .data = &imx_wdt_legacy }, + { .compatible = "fsl,vf610-wdt", .data = &imx_wdt }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, imx2_wdt_dt_ids);