Re: [PATCH 3/4] i2c: i801: Do not create iTCO watchdog when WDAT table exists

[Guenter Roeck]

On Tue, Sep 13, 2016 at 06:23:35PM +0300, Mika Westerberg wrote:
> ACPI WDAT table is the preferred way to use hardware watchdog over the
> native iTCO_wdt. Windows only uses this table for its hardware watchdog
> implementation so we should be relatively safe to trust it has been
> validated by OEMs
> 
> Prevent iTCO watchdog creation if we detect that there is ACPI WDAT table.
> 
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
>  drivers/i2c/busses/i2c-i801.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
> index 5ef9b733d153..26298af73232 100644
> --- a/drivers/i2c/busses/i2c-i801.c
> +++ b/drivers/i2c/busses/i2c-i801.c
> @@ -1486,7 +1486,9 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
>  		priv->features |= FEATURE_IRQ;
>  		priv->features |= FEATURE_SMBUS_PEC;
>  		priv->features |= FEATURE_BLOCK_BUFFER;
> -		priv->features |= FEATURE_TCO;
> +		/* If we have ACPI based watchdog use that instead */
> +		if (!acpi_has_watchdog())
> +			priv->features |= FEATURE_TCO;
>  		priv->features |= FEATURE_HOST_NOTIFY;
>  		break;
>  
> -- 
> 2.9.3
>