On 11/09/2024 09:00, Ciprian Costea wrote:
> From: Ciprian Marian Costea <ciprianmarian.costea@xxxxxxxxxxx>
>
> Add a RTC driver for NXP S32G2/S32G3 SoCs.
>
> The RTC module is used to enable Suspend to RAM (STR) support
> on NXP S32G2/S32G3 SoC based boards.
> RTC tracks clock time during system suspend.
>
...
> + priv->div512 = !!div[0];
> + priv->div32 = !!div[1];
> +
> + switch (clksel) {
> + case S32G_RTC_SOURCE_SIRC:
> + case S32G_RTC_SOURCE_FIRC:
> + priv->clk_source = clksel;
> + break;
> + default:
> + dev_err(dev, "Unsupported clksel: %d\n", clksel);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int rtc_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct rtc_priv *priv;
> + int ret = 0;
> +
> + priv = devm_kzalloc(dev, sizeof(struct rtc_priv),
sizeof(*)
> + GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->rtc_base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(priv->rtc_base)) {
> + dev_err(dev, "Failed to map registers\n");
> + return PTR_ERR(priv->rtc_base);
return dev_err_probe
> + }
> +
> + device_init_wakeup(dev, true);
> + priv->dev = dev;
> +
> + ret = priv_dts_init(priv);
> + if (ret)
> + return ret;
> +
> + ret = rtc_init(priv);
> + if (ret)
> + return ret;
> +
> + platform_set_drvdata(pdev, priv);
> + rtc_enable(priv);
> +
> + priv->rdev = devm_rtc_device_register(dev, "s32g_rtc",
> + &rtc_ops, THIS_MODULE);
> + if (IS_ERR_OR_NULL(priv->rdev)) {
> + dev_err(dev, "Error registering RTC device, err: %ld\n",
> + PTR_ERR(priv->rdev));
> + ret = PTR_ERR(priv->rdev);
> + goto disable_rtc;
> + }
> +
> + ret = devm_request_irq(dev, priv->dt_irq_id,
> + rtc_handler, 0, dev_name(dev), pdev);
> + if (ret) {
> + dev_err(&pdev->dev, "Request interrupt %d failed, error: %d\n",
> + priv->dt_irq_id, ret);
> + goto disable_rtc;
> + }
> +
> + return 0;
> +
> +disable_rtc:
> + rtc_disable(priv);
> + return ret;
> +}
> +
> +static void rtc_remove(struct platform_device *pdev)
> +{
> + struct rtc_priv *priv = platform_get_drvdata(pdev);
> +
> + rtc_disable(priv);
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static void enable_api_irq(struct device *dev, unsigned int enabled)
> +{
> + struct rtc_priv *priv = dev_get_drvdata(dev);
> + u32 api_irq = RTCC_APIEN | RTCC_APIIE;
> + u32 rtcc;
> +
> + rtcc = ioread32(priv->rtc_base + RTCC_OFFSET);
> + if (enabled)
> + rtcc |= api_irq;
> + else
> + rtcc &= ~api_irq;
> + iowrite32(rtcc, priv->rtc_base + RTCC_OFFSET);
> +}
> +
> +static int adjust_dividers(u32 sec, struct rtc_priv *priv)
> +{
> + u64 rtcval_max = U32_MAX;
> + u64 rtcval;
> +
> + priv->div32 = 0;
> + priv->div512 = 0;
> +
> + rtcval = sec * priv->rtc_hz;
> + if (rtcval < rtcval_max)
> + return 0;
> +
> + if (rtcval / 32 < rtcval_max) {
> + priv->div32 = 1;
> + return 0;
> + }
> +
> + if (rtcval / 512 < rtcval_max) {
> + priv->div512 = 1;
> + return 0;
> + }
> +
> + if (rtcval / (512 * 32) < rtcval_max) {
> + priv->div32 = 1;
> + priv->div512 = 1;
> + return 0;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int rtc_suspend(struct device *dev)
> +{
> + struct rtc_priv *init_priv = dev_get_drvdata(dev);
> + struct rtc_priv priv;
> + long long base_sec;
> + int ret = 0;
> + u32 rtcval;
> + u32 sec;
> +
> + if (!device_may_wakeup(dev))
> + return 0;
> +
> + /* Save last known timestamp before we switch clocks and reinit RTC */
> + ret = s32g_rtc_read_time(dev, &priv.base.tm);
> + if (ret)
> + return ret;
> +
> + if (init_priv->clk_source == S32G_RTC_SOURCE_SIRC)
> + return 0;
> +
> + /*
> + * Use a local copy of the RTC control block to
> + * avoid restoring it on resume path.
> + */
> + memcpy(&priv, init_priv, sizeof(priv));
> +
> + /* Switch to SIRC */
> + priv.clk_source = S32G_RTC_SOURCE_SIRC;
> +
> + ret = get_time_left(dev, init_priv, &sec);
> + if (ret)
> + return ret;
> +
> + /* Adjust for the number of seconds we'll be asleep */
> + base_sec = rtc_tm_to_time64(&init_priv->base.tm);
> + base_sec += sec;
> + rtc_time64_to_tm(base_sec, &init_priv->base.tm);
> +
> + rtc_disable(&priv);
> +
> + ret = adjust_dividers(sec, &priv);
> + if (ret) {
> + dev_err(dev, "Failed to adjust RTC dividers to match a %u seconds delay\n", sec);
> + return ret;
> + }
> +
> + ret = rtc_init(&priv);
> + if (ret)
> + return ret;
> +
> + ret = sec_to_rtcval(&priv, sec, &rtcval);
> + if (ret) {
> + dev_warn(dev, "Alarm is too far in the future\n");
> + return ret;
> + }
> +
> + s32g_rtc_alarm_irq_enable(dev, 0);
> + enable_api_irq(dev, 1);
> + iowrite32(rtcval, priv.rtc_base + APIVAL_OFFSET);
> + iowrite32(0, priv.rtc_base + RTCVAL_OFFSET);
> +
> + rtc_enable(&priv);
> +
> + return ret;
> +}
> +
> +static int rtc_resume(struct device *dev)
> +{
> + struct rtc_priv *priv = dev_get_drvdata(dev);
> + int ret;
> +
> + if (!device_may_wakeup(dev))
> + return 0;
> +
> + /* Disable wake-up interrupts */
> + enable_api_irq(dev, 0);
> +
> + /* Reinitialize the driver using the initial settings */
> + ret = rtc_init(priv);
> + if (ret)
> + return ret;
> +
> + rtc_enable(priv);
> +
> + /*
> + * Now RTCCNT has just been reset, and is out of sync with priv->base;
> + * reapply the saved time settings
> + */
> + return s32g_rtc_set_time(dev, &priv->base.tm);
> +}
> +#endif /* CONFIG_PM_SLEEP */
> +
> +static const struct of_device_id rtc_dt_ids[] = {
> + {.compatible = "nxp,s32g-rtc" },
> + { /* sentinel */ },
> +};
> +
> +static SIMPLE_DEV_PM_OPS(rtc_pm_ops,
> + rtc_suspend, rtc_resume);
> +
> +static struct platform_driver rtc_driver = {
> + .driver = {
> + .name = "s32g-rtc",
> + .pm = &rtc_pm_ops,
> + .of_match_table = of_match_ptr(rtc_dt_ids),
Drop of_match_ptr, you have here warning.
> + },
> + .probe = rtc_probe,
> + .remove_new = rtc_remove,
> +};
> +module_platform_driver(rtc_driver);
> +
> +MODULE_AUTHOR("NXP");
> +MODULE_DESCRIPTION("NXP RTC driver for S32G2/S32G3");
> +MODULE_LICENSE("GPL");
Best regards,
Krzysztof
