Re: [PATCH] watchdog: aspeed_wdt: Reorder output signal register configuration

From: Joel Stanley
Date: Tue Aug 23 2022 - 20:46:32 EST


On Fri, 19 Aug 2022 at 09:49, Chin-Ting Kuo
<chin-ting_kuo@xxxxxxxxxxxxxx> wrote:
>
> If the output driving type is push-pull mode, the output
> polarity should be selected in advance. Otherwise, an unexpected
> value will be output at the moment of changing to push-pull mode.
> Thus, output polarity, WDT18[31], must be configured before
> changing driving type, WDT18[30].
>
> Signed-off-by: Chin-Ting Kuo <chin-ting_kuo@xxxxxxxxxxxxxx>

Thanks Chin-Ting.

Fixes: 012c04601f9d ("watchdog: aspeed: Support configuration of
external signal properties")
Reviewed-by: Joel Stanley <joel@xxxxxxxxx>

I wonder if any of these machines hit the bug:

$ git grep -l aspeed,ext-push-pull arch/arm/boot/dts/
arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts
arch/arm/boot/dts/aspeed-bmc-inspur-fp5280g2.dts
arch/arm/boot/dts/aspeed-bmc-opp-mihawk.dts
arch/arm/boot/dts/aspeed-bmc-opp-mowgli.dts
arch/arm/boot/dts/aspeed-bmc-opp-swift.dts
arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts
arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts


> ---
> drivers/watchdog/aspeed_wdt.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
> index 436571b6fc79..a03e4ff812a2 100644
> --- a/drivers/watchdog/aspeed_wdt.c
> +++ b/drivers/watchdog/aspeed_wdt.c
> @@ -325,18 +325,18 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
> u32 reg = readl(wdt->base + WDT_RESET_WIDTH);
>
> reg &= config->ext_pulse_width_mask;
> - if (of_property_read_bool(np, "aspeed,ext-push-pull"))
> - reg |= WDT_PUSH_PULL_MAGIC;
> + if (of_property_read_bool(np, "aspeed,ext-active-high"))
> + reg |= WDT_ACTIVE_HIGH_MAGIC;
> else
> - reg |= WDT_OPEN_DRAIN_MAGIC;
> + reg |= WDT_ACTIVE_LOW_MAGIC;
>
> writel(reg, wdt->base + WDT_RESET_WIDTH);
>
> reg &= config->ext_pulse_width_mask;
> - if (of_property_read_bool(np, "aspeed,ext-active-high"))
> - reg |= WDT_ACTIVE_HIGH_MAGIC;
> + if (of_property_read_bool(np, "aspeed,ext-push-pull"))
> + reg |= WDT_PUSH_PULL_MAGIC;
> else
> - reg |= WDT_ACTIVE_LOW_MAGIC;
> + reg |= WDT_OPEN_DRAIN_MAGIC;
>
> writel(reg, wdt->base + WDT_RESET_WIDTH);
> }
> --
> 2.25.1
>