Re: [PATCH v1] soc: qcom: ice: Prevent UFS probe deferral on ICE probe failure

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 3.12.2024 3:40 AM, Yuvaraj Ranganathan wrote:
> When the ICE key programming interface is unavailable, the ice create
> function fails, causing the probe to set NULL as the driver data. As a 
> result, when the UFS driver reads the ICE driver data and encounters a 
> NULL, leading to the deferral of the UFS probe and preventing the device
> from booting to the shell.
> 
> To address this issue, modify the behavior to return an "operation not
> supported" error when the ICE key programming interface is unavailable.
> Additionally, mark this error in a global variable. When the UFS driver
> attempts to read the ICE driver data, it will check for this error and
> return it, rather than deferring the probe.
> 
> Signed-off-by: Yuvaraj Ranganathan <quic_yrangana@quicinc.com>
> ---
>  drivers/soc/qcom/ice.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/soc/qcom/ice.c b/drivers/soc/qcom/ice.c
> index 393d2d1d275f..160916cb8fb0 100644
> --- a/drivers/soc/qcom/ice.c
> +++ b/drivers/soc/qcom/ice.c
> @@ -41,6 +41,8 @@
>  #define qcom_ice_readl(engine, reg)	\
>  	readl((engine)->base + (reg))
>  
> +static bool qcom_ice_create_error;

So you could drop this..

> +
>  struct qcom_ice {
>  	struct device *dev;
>  	void __iomem *base;
> @@ -215,7 +217,7 @@ static struct qcom_ice *qcom_ice_create(struct device *dev,
>  
>  	if (!qcom_scm_ice_available()) {
>  		dev_warn(dev, "ICE SCM interface not found\n");
> -		return NULL;
> +		return ERR_PTR(-EOPNOTSUPP);
>  	}
>  
>  	engine = devm_kzalloc(dev, sizeof(*engine), GFP_KERNEL);
> @@ -303,6 +305,9 @@ struct qcom_ice *of_qcom_ice_get(struct device *dev)
>  		return ERR_PTR(-EPROBE_DEFER);
>  	}
>  
> +	if (qcom_ice_create_error)
> +		return ERR_PTR(-EOPNOTSUPP);
> +
>  	ice = platform_get_drvdata(pdev);
>  	if (!ice) {

..and check for || IS_ERR(ice) here

if I'm reading things right

Konrad