* [PATCH 0/2] watchdog: imx_wdt2: Enable ping on suspend support @ 2022-01-09 11:41 Alistair Francis 2022-01-09 11:41 ` [PATCH 1/2] watchdog: imx2_wdg: Alow ping on suspend Alistair Francis 2022-01-09 11:41 ` [PATCH 2/2] ARM: dts: imx7d: remarkable2: set ping-during-suspend for watchdog Alistair Francis 0 siblings, 2 replies; 5+ messages in thread From: Alistair Francis @ 2022-01-09 11:41 UTC (permalink / raw) To: linux-kernel, linux, shawnguo, wim, linux-watchdog, s.hauer, linux-arm-kernel Cc: linux-imx, kernel, festevam, devicetree, robh+dt, Alistair Francis When running Linux on the reMarkable2 tablet the device reboots two minutes after suspend. This is because we don't go into low power mode so the watchdog timer is still running and triggers a reboot. This series adds optional support for ping on suspend for the i.MX watchdog timer and then enables it for the reMarkable2 tablet. Alistair Francis (2): watchdog: imx2_wdg: Alow ping on suspend ARM: dts: imx7d: remarkable2: set ping-during-suspend for watchdog .../bindings/watchdog/fsl-imx-wdt.yaml | 7 ++++++ arch/arm/boot/dts/imx7d-remarkable2.dts | 1 + drivers/watchdog/imx2_wdt.c | 22 +++++++++++++------ 3 files changed, 23 insertions(+), 7 deletions(-) -- 2.31.1 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 1/2] watchdog: imx2_wdg: Alow ping on suspend 2022-01-09 11:41 [PATCH 0/2] watchdog: imx_wdt2: Enable ping on suspend support Alistair Francis @ 2022-01-09 11:41 ` Alistair Francis 2022-01-13 18:55 ` Stefan Wahren 2022-01-09 11:41 ` [PATCH 2/2] ARM: dts: imx7d: remarkable2: set ping-during-suspend for watchdog Alistair Francis 1 sibling, 1 reply; 5+ messages in thread From: Alistair Francis @ 2022-01-09 11:41 UTC (permalink / raw) To: linux-kernel, linux, shawnguo, wim, linux-watchdog, s.hauer, linux-arm-kernel Cc: linux-imx, kernel, festevam, devicetree, robh+dt, Alistair Francis The i.MX watchdog cannot be disabled by softwrae once it has been enabled. This means that it can't be stopped before suspend. For systems that enter low power mode this is fine, as the watchdog will be automatically stopped by hardwrae in low power mode. Not all i.MX platforms support low power mode in the mainline kernel. For example the i.MX7D does not enter low power mode and so will be rebooted 2 minutes after entering freeze or mem sleep states. This patch introduces a device tree property "fsl,ping-during-suspend" that can be used to enable ping on suspend support for these systems. Signed-off-by: Alistair Francis <alistair@alistair23.me> --- .../bindings/watchdog/fsl-imx-wdt.yaml | 7 ++++++ drivers/watchdog/imx2_wdt.c | 22 +++++++++++++------ 2 files changed, 22 insertions(+), 7 deletions(-) diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml index fb7695515be1..b8660a3c456c 100644 --- a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml +++ b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml @@ -55,6 +55,13 @@ properties: If present, the watchdog device is configured to assert its external reset (WDOG_B) instead of issuing a software reset. + fsl,ping-during-suspend: + $ref: /schemas/types.yaml#/definitions/flag + description: | + If present, the kernel will ping the watchdog during suspend. + This should be used on platforms that don't enter low power mode + during suspend. + required: - compatible - interrupts diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c index 51bfb796898b..9a5fdb3173a8 100644 --- a/drivers/watchdog/imx2_wdt.c +++ b/drivers/watchdog/imx2_wdt.c @@ -66,6 +66,7 @@ struct imx2_wdt_device { struct watchdog_device wdog; bool ext_reset; bool clk_is_on; + bool no_ping; }; static bool nowayout = WATCHDOG_NOWAYOUT; @@ -312,12 +313,14 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) wdev->ext_reset = of_property_read_bool(dev->of_node, "fsl,ext-reset-output"); + wdev->no_ping = !of_property_read_bool(dev->of_node, "fsl,ping-during-suspend"); platform_set_drvdata(pdev, wdog); watchdog_set_drvdata(wdog, wdev); watchdog_set_nowayout(wdog, nowayout); watchdog_set_restart_priority(wdog, 128); watchdog_init_timeout(wdog, timeout, dev); - watchdog_stop_ping_on_suspend(wdog); + if (wdev->no_ping) + watchdog_stop_ping_on_suspend(wdog); if (imx2_wdt_is_running(wdev)) { imx2_wdt_set_timeout(wdog, wdog->timeout); @@ -366,9 +369,11 @@ static int __maybe_unused imx2_wdt_suspend(struct device *dev) imx2_wdt_ping(wdog); } - clk_disable_unprepare(wdev->clk); + if (wdev->no_ping) { + clk_disable_unprepare(wdev->clk); - wdev->clk_is_on = false; + wdev->clk_is_on = false; + } return 0; } @@ -380,11 +385,14 @@ static int __maybe_unused imx2_wdt_resume(struct device *dev) struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); int ret; - ret = clk_prepare_enable(wdev->clk); - if (ret) - return ret; + if (wdev->no_ping) { + ret = clk_prepare_enable(wdev->clk); - wdev->clk_is_on = true; + if (ret) + return ret; + + wdev->clk_is_on = true; + } if (watchdog_active(wdog) && !imx2_wdt_is_running(wdev)) { /* -- 2.31.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 1/2] watchdog: imx2_wdg: Alow ping on suspend 2022-01-09 11:41 ` [PATCH 1/2] watchdog: imx2_wdg: Alow ping on suspend Alistair Francis @ 2022-01-13 18:55 ` Stefan Wahren 2022-01-13 19:43 ` Guenter Roeck 0 siblings, 1 reply; 5+ messages in thread From: Stefan Wahren @ 2022-01-13 18:55 UTC (permalink / raw) To: Alistair Francis, linux-kernel, linux, shawnguo, wim, linux-watchdog, s.hauer, linux-arm-kernel Cc: linux-imx, kernel, festevam, devicetree, robh+dt Hi, Am 09.01.22 um 12:41 schrieb Alistair Francis: > The i.MX watchdog cannot be disabled by softwrae once it has been s/softwrae/software/ > enabled. This means that it can't be stopped before suspend. > > For systems that enter low power mode this is fine, as the watchdog will > be automatically stopped by hardwrae in low power mode. Not all i.MX s/hardwrae/hardware/ > platforms support low power mode in the mainline kernel. For example the > i.MX7D does not enter low power mode and so will be rebooted 2 minutes > after entering freeze or mem sleep states. > > This patch introduces a device tree property "fsl,ping-during-suspend" > that can be used to enable ping on suspend support for these systems. Introducing vendor specific properties for Linux behavior should be avoided. The DT should describe just the hardware. In case i.mx7d is affected, how about enabling this workaround for compatible fsl,imx7d-wdt? This has the advantage that in case low power mode will be implemented <https://elixir.bootlin.com/linux/latest/B/ident/fsl%2Cimx7d-wdt>, we don't have to care about DTB files. Best regards > > Signed-off-by: Alistair Francis <alistair@alistair23.me> > --- > .../bindings/watchdog/fsl-imx-wdt.yaml | 7 ++++++ > drivers/watchdog/imx2_wdt.c | 22 +++++++++++++------ > 2 files changed, 22 insertions(+), 7 deletions(-) > > diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml > index fb7695515be1..b8660a3c456c 100644 > --- a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml > +++ b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.yaml > @@ -55,6 +55,13 @@ properties: > If present, the watchdog device is configured to assert its > external reset (WDOG_B) instead of issuing a software reset. > > + fsl,ping-during-suspend: > + $ref: /schemas/types.yaml#/definitions/flag > + description: | > + If present, the kernel will ping the watchdog during suspend. > + This should be used on platforms that don't enter low power mode > + during suspend. > + > required: > - compatible > - interrupts > diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c > index 51bfb796898b..9a5fdb3173a8 100644 > --- a/drivers/watchdog/imx2_wdt.c > +++ b/drivers/watchdog/imx2_wdt.c > @@ -66,6 +66,7 @@ struct imx2_wdt_device { > struct watchdog_device wdog; > bool ext_reset; > bool clk_is_on; > + bool no_ping; > }; > > static bool nowayout = WATCHDOG_NOWAYOUT; > @@ -312,12 +313,14 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) > > wdev->ext_reset = of_property_read_bool(dev->of_node, > "fsl,ext-reset-output"); > + wdev->no_ping = !of_property_read_bool(dev->of_node, "fsl,ping-during-suspend"); > platform_set_drvdata(pdev, wdog); > watchdog_set_drvdata(wdog, wdev); > watchdog_set_nowayout(wdog, nowayout); > watchdog_set_restart_priority(wdog, 128); > watchdog_init_timeout(wdog, timeout, dev); > - watchdog_stop_ping_on_suspend(wdog); > + if (wdev->no_ping) > + watchdog_stop_ping_on_suspend(wdog); > > if (imx2_wdt_is_running(wdev)) { > imx2_wdt_set_timeout(wdog, wdog->timeout); > @@ -366,9 +369,11 @@ static int __maybe_unused imx2_wdt_suspend(struct device *dev) > imx2_wdt_ping(wdog); > } > > - clk_disable_unprepare(wdev->clk); > + if (wdev->no_ping) { > + clk_disable_unprepare(wdev->clk); > > - wdev->clk_is_on = false; > + wdev->clk_is_on = false; > + } > > return 0; > } > @@ -380,11 +385,14 @@ static int __maybe_unused imx2_wdt_resume(struct device *dev) > struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > int ret; > > - ret = clk_prepare_enable(wdev->clk); > - if (ret) > - return ret; > + if (wdev->no_ping) { > + ret = clk_prepare_enable(wdev->clk); > > - wdev->clk_is_on = true; > + if (ret) > + return ret; > + > + wdev->clk_is_on = true; > + } > > if (watchdog_active(wdog) && !imx2_wdt_is_running(wdev)) { > /* ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/2] watchdog: imx2_wdg: Alow ping on suspend 2022-01-13 18:55 ` Stefan Wahren @ 2022-01-13 19:43 ` Guenter Roeck 0 siblings, 0 replies; 5+ messages in thread From: Guenter Roeck @ 2022-01-13 19:43 UTC (permalink / raw) To: Stefan Wahren, Alistair Francis, linux-kernel, shawnguo, wim, linux-watchdog, s.hauer, linux-arm-kernel Cc: linux-imx, kernel, festevam, devicetree, robh+dt On 1/13/22 10:55 AM, Stefan Wahren wrote: > Hi, > > Am 09.01.22 um 12:41 schrieb Alistair Francis: >> The i.MX watchdog cannot be disabled by softwrae once it has been > s/softwrae/software/ >> enabled. This means that it can't be stopped before suspend. >> >> For systems that enter low power mode this is fine, as the watchdog will >> be automatically stopped by hardwrae in low power mode. Not all i.MX > s/hardwrae/hardware/ >> platforms support low power mode in the mainline kernel. For example the >> i.MX7D does not enter low power mode and so will be rebooted 2 minutes >> after entering freeze or mem sleep states. >> >> This patch introduces a device tree property "fsl,ping-during-suspend" >> that can be used to enable ping on suspend support for these systems. > > Introducing vendor specific properties for Linux behavior should be > avoided. The DT should describe just the hardware. > > In case i.mx7d is affected, how about enabling this workaround for > compatible fsl,imx7d-wdt? This has the advantage that in case low power > mode will be implemented > <https://elixir.bootlin.com/linux/latest/B/ident/fsl%2Cimx7d-wdt>, we > don't have to care about DTB files. > Agreed. Guenter ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 2/2] ARM: dts: imx7d: remarkable2: set ping-during-suspend for watchdog 2022-01-09 11:41 [PATCH 0/2] watchdog: imx_wdt2: Enable ping on suspend support Alistair Francis 2022-01-09 11:41 ` [PATCH 1/2] watchdog: imx2_wdg: Alow ping on suspend Alistair Francis @ 2022-01-09 11:41 ` Alistair Francis 1 sibling, 0 replies; 5+ messages in thread From: Alistair Francis @ 2022-01-09 11:41 UTC (permalink / raw) To: linux-kernel, linux, shawnguo, wim, linux-watchdog, s.hauer, linux-arm-kernel Cc: linux-imx, kernel, festevam, devicetree, robh+dt, Alistair Francis Set ping-during-suspend for the reMarkable watchdog timer to avoid the device rebooting when asleep. Signed-off-by: Alistair Francis <alistair@alistair23.me> --- arch/arm/boot/dts/imx7d-remarkable2.dts | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm/boot/dts/imx7d-remarkable2.dts b/arch/arm/boot/dts/imx7d-remarkable2.dts index 89cbf13097a4..99a453108af7 100644 --- a/arch/arm/boot/dts/imx7d-remarkable2.dts +++ b/arch/arm/boot/dts/imx7d-remarkable2.dts @@ -115,6 +115,7 @@ &wdog1 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_wdog>; fsl,ext-reset-output; + fsl,ping-during-suspend; }; &iomuxc { -- 2.31.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-01-13 19:43 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-01-09 11:41 [PATCH 0/2] watchdog: imx_wdt2: Enable ping on suspend support Alistair Francis 2022-01-09 11:41 ` [PATCH 1/2] watchdog: imx2_wdg: Alow ping on suspend Alistair Francis 2022-01-13 18:55 ` Stefan Wahren 2022-01-13 19:43 ` Guenter Roeck 2022-01-09 11:41 ` [PATCH 2/2] ARM: dts: imx7d: remarkable2: set ping-during-suspend for watchdog Alistair Francis
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