Re: [PATCH] rtc: pcf2127: add support for accessing internal static RAM

[Alexandre Belloni <alexandre.belloni@bootlin.com>]

Hi,

On 20/05/2018 15:37:23+0200, Uwe Kleine-König wrote:
>  static int pcf2127_probe(struct device *dev, struct regmap *regmap,
> -			const char *name)
> +			const char *name, bool has_nvmem)
>  {
>  	struct pcf2127 *pcf2127;
> +	int ret = 0;
>  
>  	dev_dbg(dev, "%s\n", __func__);
>  
> @@ -200,8 +242,21 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
>  
>  	pcf2127->rtc = devm_rtc_device_register(dev, name, &pcf2127_rtc_ops,
>  						THIS_MODULE);
> +	if (IS_ERR(pcf2127->rtc))
> +		return PTR_ERR(pcf2127->rtc);
> +
> +	if (has_nvmem) {
> +		struct nvmem_config nvmem_cfg = {
> +			.priv = pcf2127,
> +			.reg_read = pcf2127_nvmem_read,
> +			.reg_write = pcf2127_nvmem_write,
> +			.size = 512,
> +		};
> +
> +		ret = rtc_nvmem_register(pcf2127->rtc, &nvmem_cfg);
> +	}
>  
> -	return PTR_ERR_OR_ZERO(pcf2127->rtc);
> +	return ret;

You must not return an error here once devm_rtc_device_register has
succeeded. You have the choice between ignoring the nvmem registration
error or switching to devm_rtc_allocate_device/rtc_register_device().

-- 
Alexandre Belloni, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com