Re: [PATCH 4/5] input: drv260x: Stop waiting for GO bit clearing after timeout

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Thu, Feb 12, 2026 at 01:46:54AM +0200, Yauhen Kharuzhy wrote:
> If something goes wrong during effect playing or calibration, the GO bit
> may not be cleared after some time, and the driver will get stuck.
> To prevent this, add a timeout to the waiting loop.
> 
> Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
> ---
>  drivers/input/misc/drv260x.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/input/misc/drv260x.c b/drivers/input/misc/drv260x.c
> index f08a3d6c3ed8..f7bfac6d3973 100644
> --- a/drivers/input/misc/drv260x.c
> +++ b/drivers/input/misc/drv260x.c
> @@ -173,6 +173,12 @@
>  #define DRV260X_AUTOCAL_TIME_500MS		(2 << 4)
>  #define DRV260X_AUTOCAL_TIME_1000MS		(3 << 4)
>  
> +/*
> + * Timeout for waiting for the GO status bit, in seconds. Should be reasonably
> + * large to allow long-duration effects and a calibration cycle
> + */
> +#define DRV260X_GO_TIMEOUT_S 5
> +
>  /**
>   * struct drv260x_data -
>   * @input_dev: Pointer to the input device
> @@ -339,6 +345,7 @@ static int drv260x_init(struct drv260x_data *haptics)
>  {
>  	int error;
>  	unsigned int cal_buf;
> +	unsigned long timeout;
>  	u8 id;
>  
>  	error = regmap_read(haptics->regmap, DRV260X_STATUS, &cal_buf);
> @@ -442,6 +449,7 @@ static int drv260x_init(struct drv260x_data *haptics)
>  		return error;
>  	}
>  
> +	timeout = jiffies + DRV260X_GO_TIMEOUT_S * HZ;
>  	do {
>  		usleep_range(15000, 15500);
>  		error = regmap_read(haptics->regmap, DRV260X_GO, &cal_buf);
> @@ -451,6 +459,10 @@ static int drv260x_init(struct drv260x_data *haptics)
>  				error);
>  			return error;
>  		}
> +		if (jiffies - timeout <= 0) {

time_after()

> +			dev_err(&haptics->client->dev, "GO timeout\n");

This should be a warning, not error, since we are continuing.

But actually, shouldn't we signal an error? This is probe path and if
the controller does not ever signal readiness I do not think we should
pretend that it will work.

> +			break;
> +		}
>  	} while (cal_buf == DRV260X_GO_BIT);

Thanks.

-- 
Dmitry