On 13/02/2025 19:46:15+0100, Alexander Sverdlin wrote:
> +static int cv1800_rtc_probe(struct platform_device *pdev)
> +{
> + struct cv1800_rtc_priv *rtc;
> + u32 ctrl_val;
> + void __iomem *base;
> + int ret;
> +
> + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
> + if (!rtc)
> + return -ENOMEM;
> +
> + base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + rtc->rtc_map = devm_regmap_init_mmio(&pdev->dev, base,
> + &cv1800_rtc_regmap_config);
> + if (IS_ERR(rtc->rtc_map))
> + return PTR_ERR(rtc->rtc_map);
> +
> + rtc->irq = platform_get_irq(pdev, 0);
> + if (rtc->irq < 0)
> + return rtc->irq;
> +
> + rtc->clk = devm_clk_get_enabled(&pdev->dev, NULL);
> + if (IS_ERR(rtc->clk))
> + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->clk),
> + "clk not found\n");
> +
> + platform_set_drvdata(pdev, rtc);
> +
> + device_init_wakeup(&pdev->dev, 1);
> +
> + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
> + if (IS_ERR(rtc->rtc_dev))
> + return PTR_ERR(rtc->rtc_dev);
> +
> + rtc->rtc_dev->ops = &cv1800_rtc_ops;
> + rtc->rtc_dev->range_max = U32_MAX;
> +
> + ret = devm_request_irq(&pdev->dev, rtc->irq, cv1800_rtc_irq_handler,
> + IRQF_TRIGGER_HIGH, "rtc alarm", rtc);
> + if (ret)
> + return dev_err_probe(&pdev->dev, ret,
> + "cannot register interrupt handler\n");
> +
> + rtc_enable_sec_counter(rtc);
Really, this must be avoided, this loses precious information and
changing it later will break users. What must be done is to check
whether the RTC is started in .read_time if this is not the case, return
-EINVAL instead of an invalid date/time.
The RTC must be started once the time is set for the first time. This
ensures we can detect when the time is invalid.
> +
> + return devm_rtc_register_device(rtc->rtc_dev);
> +}
> +
> +static const struct of_device_id cv1800_dt_ids[] = {
> + { .compatible = "sophgo,cv1800-rtc" },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, cv1800_dt_ids);
> +
> +static struct platform_driver cv1800_rtc_driver = {
> + .driver = {
> + .name = "sophgo-cv1800-rtc",
> + .of_match_table = cv1800_dt_ids,
> + },
> + .probe = cv1800_rtc_probe,
> +};
> +
> +module_platform_driver(cv1800_rtc_driver);
> +MODULE_AUTHOR("Jingbao Qiu");
> +MODULE_DESCRIPTION("Sophgo cv1800 RTC Driver");
> +MODULE_LICENSE("GPL");
> --
> 2.48.1
>
--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
