Re: [PATCH v4 2/5] soc: qcom: llcc: Add regmap for Broadcast_AND region

[Krzysztof Kozlowski]

On 29/03/2024 22:53, Unnathi Chalicheemala wrote:
> Define new regmap structure for Broadcast_AND region and initialize
> this regmap when HW block version is greater than 4.1, otherwise
> initialize as a NULL pointer for backwards compatibility.
> 

> +	struct regmap *regmap;
>  	u32 act_ctrl_reg;
>  	u32 act_clear_reg;
>  	u32 status_reg;
> @@ -849,7 +850,8 @@ static int llcc_update_act_ctrl(u32 sid,
>  		return ret;
>  
>  	if (drv_data->version >= LLCC_VERSION_4_1_0_0) {
> -		ret = regmap_read_poll_timeout(drv_data->bcast_regmap, status_reg,
> +		regmap = drv_data->bcast_and_regmap ?: drv_data->bcast_regmap;
> +		ret = regmap_read_poll_timeout(regmap, status_reg,
>  				      slice_status, (slice_status & ACT_COMPLETE),
>  				      0, LLCC_STATUS_READ_DELAY);
>  		if (ret)
> @@ -1284,6 +1286,16 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>  
>  	drv_data->version = version;
>  
> +	/* Applicable only when drv_data->version >= 4.1 */
> +	drv_data->bcast_and_regmap = qcom_llcc_init_mmio(pdev, i + 1, "llcc_broadcast_and_base");
> +	if (IS_ERR(drv_data->bcast_and_regmap)) {

I am pretty sure this breaks all users. Can you please explain how do
you maintain ABI and that IS_ERR() is applied only for version >= 4.1?

Best regards,
Krzysztof