Re: [PATCH v3 1/2] watchdog: sp805_wdt: deassert the reset if available

From: Guenter Roeck
Date: Wed Feb 21 2024 - 07:55:58 EST


On Wed, Feb 21, 2024 at 07:56:41PM +0800, Yang Xiwen via B4 Relay wrote:
> From: Yang Xiwen <forbidden405@xxxxxxxxxxx>
>
> According to the datasheet, the core has an WDOGRESn input signal that
> needs to be deasserted before being operational. Implement it in the
> driver.
>
> Signed-off-by: Yang Xiwen <forbidden405@xxxxxxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
> drivers/watchdog/sp805_wdt.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
> index 2756ed54ca3d..109e2e37e8f0 100644
> --- a/drivers/watchdog/sp805_wdt.c
> +++ b/drivers/watchdog/sp805_wdt.c
> @@ -25,6 +25,7 @@
> #include <linux/moduleparam.h>
> #include <linux/pm.h>
> #include <linux/property.h>
> +#include <linux/reset.h>
> #include <linux/slab.h>
> #include <linux/spinlock.h>
> #include <linux/types.h>
> @@ -232,6 +233,7 @@ static int
> sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
> {
> struct sp805_wdt *wdt;
> + struct reset_control *rst;
> u64 rate = 0;
> int ret = 0;
>
> @@ -264,6 +266,12 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
> return -ENODEV;
> }
>
> + rst = devm_reset_control_get_optional_exclusive(&adev->dev, NULL);
> + if (IS_ERR(rst))
> + return dev_err_probe(&adev->dev, PTR_ERR(rst), "Can not get reset\n");
> +
> + reset_control_deassert(rst);
> +
> wdt->adev = adev;
> wdt->wdd.info = &wdt_info;
> wdt->wdd.ops = &wdt_ops;
>
> --
> 2.43.0
>