Re: [PATCH v3] usb: misc: ljca: Fix enumeration error on Dell Latitude 9420

[Andi Shyti <andi.shyti@linux.intel.com>]

Hi Hans,

On Tue, Nov 21, 2023 at 09:32:05PM +0100, Hans de Goede wrote:
> Not all LJCA chips implement SPI and on chips without SPI reading
> the SPI descriptors will timeout.
> 
> On laptop models like the Dell Latitude 9420, this is expected behavior
> and not an error.
> 
> Modify the driver to continue without instantiating a SPI auxbus child,
> instead of failing to probe() the whole LJCA chip.
> 
> Fixes: acd6199f195d ("usb: Add support for Intel LJCA device")
> Cc: stable@vger.kernel.org

did this already make it to stable? I think it is not needed.

> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> Reviewed-by: Wentong Wu <wentong.wu@intel.com>
> Link: https://lore.kernel.org/r/20231104175104.38786-1-hdegoede@redhat.com

Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

Thanks,
Andi

> ---
> Changes in v3:
> - Fix commit-id in fixes tag
> 
> Changes in v2:
> - Small commit msg + comment fixes
> - Add Fixes tag + Cc: stable
> ---
>  drivers/usb/misc/usb-ljca.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/misc/usb-ljca.c b/drivers/usb/misc/usb-ljca.c
> index c9decd0396d4..a280d3a54b18 100644
> --- a/drivers/usb/misc/usb-ljca.c
> +++ b/drivers/usb/misc/usb-ljca.c
> @@ -656,10 +656,11 @@ static int ljca_enumerate_spi(struct ljca_adapter *adap)
>  	unsigned int i;
>  	int ret;
>  
> +	/* Not all LJCA chips implement SPI, a timeout reading the descriptors is normal */
>  	ret = ljca_send(adap, LJCA_CLIENT_MNG, LJCA_MNG_ENUM_SPI, NULL, 0, buf,
>  			sizeof(buf), true, LJCA_ENUM_CLIENT_TIMEOUT_MS);
>  	if (ret < 0)
> -		return ret;
> +		return (ret == -ETIMEDOUT) ? 0 : ret;
>  
>  	/* check firmware response */
>  	desc = (struct ljca_spi_descriptor *)buf;
> -- 
> 2.41.0