rtc: rework rtc_register_device() resource management

rtc_register_device() is a managed interface but it doesn't use devres
by itself - instead it marks an rtc_device as "registered" and the devres
callback for devm_rtc_allocate_device() takes care of resource release.

This doesn't correspond with the design behind devres where managed
structures should not be aware of being managed. The correct solution
here is to register a separate devres callback for unregistering the
device.

While at it: rename rtc_register_device() to devm_rtc_register_device()
and add it to the list of managed interfaces in devres.rst. This way we
can avoid any potential confusion of driver developers who may expect
there to exist a corresponding unregister function.

Signed-off-by: Bartosz Golaszewski <[e-mail]>
Signed-off-by: Alexandre Belloni <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

Documentation/driver-api/driver-model/devres.rst

···
 RTC
   devm_rtc_device_register()
   devm_rtc_allocate_device()
+  devm_rtc_register_device()
   devm_rtc_nvmem_register()
 
 SERDEV

arch/alpha/kernel/rtc.c

···
 		rtc->ops = &remote_rtc_ops;
 #endif
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 device_initcall(alpha_rtc_init);

drivers/mfd/menelaus.c

···
 		menelaus_write_reg(MENELAUS_RTC_CTRL, m->rtc_control);
 	}
 
-	err = rtc_register_device(m->rtc);
+	err = devm_rtc_register_device(m->rtc);
 	if (err) {
 		if (alarm) {
 			menelaus_remove_irq_work(MENELAUS_RTCALM_IRQ);

drivers/rtc/class.c

···
  *
  * @rtc: the RTC class device to destroy
  */
-static void rtc_device_unregister(struct rtc_device *rtc)
+static void devm_rtc_unregister_device(void *data)
 {
+	struct rtc_device *rtc = data;
+
 	mutex_lock(&rtc->ops_lock);
 	/*
 	 * Remove innards of this RTC, then disable it, before
···
 {
 	struct rtc_device *rtc = *(struct rtc_device **)res;
 
-	if (rtc->registered)
-		rtc_device_unregister(rtc);
-	else
-		put_device(&rtc->dev);
+	put_device(&rtc->dev);
 }
 
 struct rtc_device *devm_rtc_allocate_device(struct device *dev)
···
 }
 EXPORT_SYMBOL_GPL(devm_rtc_allocate_device);
 
-int __rtc_register_device(struct module *owner, struct rtc_device *rtc)
+int __devm_rtc_register_device(struct module *owner, struct rtc_device *rtc)
 {
 	struct rtc_wkalrm alrm;
 	int err;
···
 
 	rtc_proc_add_device(rtc);
 
-	rtc->registered = true;
 	dev_info(rtc->dev.parent, "registered as %s\n",
 		 dev_name(&rtc->dev));
 
···
 		rtc_hctosys(rtc);
 #endif
 
-	return 0;
+	return devm_add_action_or_reset(rtc->dev.parent,
+					devm_rtc_unregister_device, rtc);
 }
-EXPORT_SYMBOL_GPL(__rtc_register_device);
+EXPORT_SYMBOL_GPL(__devm_rtc_register_device);
 
 /**
  * devm_rtc_device_register - resource managed rtc_device_register()
···
 
 	rtc->ops = ops;
 
-	err = __rtc_register_device(owner, rtc);
+	err = __devm_rtc_register_device(owner, rtc);
 	if (err)
 		return ERR_PTR(err);
 

drivers/rtc/rtc-88pm80x.c

···
 	info->rtc_dev->ops = &pm80x_rtc_ops;
 	info->rtc_dev->range_max = U32_MAX;
 
-	ret = rtc_register_device(info->rtc_dev);
+	ret = devm_rtc_register_device(info->rtc_dev);
 	if (ret)
 		goto out_rtc;
 

drivers/rtc/rtc-88pm860x.c

···
 	info->rtc_dev->ops = &pm860x_rtc_ops;
 	info->rtc_dev->range_max = U32_MAX;
 
-	ret = rtc_register_device(info->rtc_dev);
+	ret = devm_rtc_register_device(info->rtc_dev);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ab-b5ze-s3.c

···
 		}
 	}
 
-	ret = rtc_register_device(data->rtc);
+	ret = devm_rtc_register_device(data->rtc);
 
 err:
 	if (ret && data->irq)

drivers/rtc/rtc-ab-eoz9.c

···
 	data->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	data->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	ret = rtc_register_device(data->rtc);
+	ret = devm_rtc_register_device(data->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ab3100.c

···
 
 	platform_set_drvdata(pdev, rtc);
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct platform_driver ab3100_rtc_driver = {

drivers/rtc/rtc-ab8500.c

···
 	if (err)
 		return err;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static int ab8500_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-abx80x.c

···
 		return err;
 	}
 
-	return rtc_register_device(priv->rtc);
+	return devm_rtc_register_device(priv->rtc);
 }
 
 static const struct i2c_device_id abx80x_id[] = {

drivers/rtc/rtc-ac100.c

···
 	if (ret)
 		return ret;
 
-	return rtc_register_device(chip->rtc);
+	return devm_rtc_register_device(chip->rtc);
 }
 
 static int ac100_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-armada38x.c

···
 
 	rtc->rtc_dev->range_max = U32_MAX;
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 #ifdef CONFIG_PM_SLEEP

drivers/rtc/rtc-aspeed.c

···
 	rtc->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_1900;
 	rtc->rtc_dev->range_max = 38814989399LL; /* 3199-12-31 23:59:59 */
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 static const struct of_device_id aspeed_rtc_match[] = {

drivers/rtc/rtc-at91rm9200.c

···
 
 	rtc->range_min = RTC_TIMESTAMP_BEGIN_1900;
 	rtc->range_max = RTC_TIMESTAMP_END_2099;
-	ret = rtc_register_device(rtc);
+	ret = devm_rtc_register_device(rtc);
 	if (ret)
 		goto err_clk;
 

drivers/rtc/rtc-at91sam9.c

···
 		dev_warn(&pdev->dev, "%s: SET TIME!\n",
 			 dev_name(&rtc->rtcdev->dev));
 
-	return rtc_register_device(rtc->rtcdev);
+	return devm_rtc_register_device(rtc->rtcdev);
 
 err_clk:
 	clk_disable_unprepare(rtc->sclk);

drivers/rtc/rtc-au1xxx.c

···
 
 	platform_set_drvdata(pdev, rtcdev);
 
-	return rtc_register_device(rtcdev);
+	return devm_rtc_register_device(rtcdev);
 }
 
 static struct platform_driver au1xrtc_driver = {

drivers/rtc/rtc-bd70528.c

···
 		}
 	}
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static const struct platform_device_id bd718x7_rtc_id[] = {

drivers/rtc/rtc-brcmstb-waketimer.c

···
 	timer->rtc->ops = &brcmstb_waketmr_ops;
 	timer->rtc->range_max = U32_MAX;
 
-	ret = rtc_register_device(timer->rtc);
+	ret = devm_rtc_register_device(timer->rtc);
 	if (ret)
 		goto err_notifier;
 

drivers/rtc/rtc-cadence.c

···
 	writel(0, crtc->regs + CDNS_RTC_HMR);
 	writel(CDNS_RTC_KRTCR_KRTC, crtc->regs + CDNS_RTC_KRTCR);
 
-	ret = rtc_register_device(crtc->rtc_dev);
+	ret = devm_rtc_register_device(crtc->rtc_dev);
 	if (ret)
 		goto err_disable_wakeup;
 

drivers/rtc/rtc-cmos.c

···
 		cmos_rtc.rtc->ops = &cmos_rtc_ops_no_alarm;
 	}
 
-	retval = rtc_register_device(cmos_rtc.rtc);
+	retval = devm_rtc_register_device(cmos_rtc.rtc);
 	if (retval)
 		goto cleanup2;
 

drivers/rtc/rtc-coh901331.c

···
 
 	platform_set_drvdata(pdev, rtap);
 
-	ret = rtc_register_device(rtap->rtc);
+	ret = devm_rtc_register_device(rtap->rtc);
 	if (ret)
 		goto out_no_rtc;
 

drivers/rtc/rtc-cpcap.c

···
 		/* ignore error and continue without wakeup support */
 	}
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 static const struct of_device_id cpcap_rtc_of_match[] = {

drivers/rtc/rtc-cros-ec.c

···
 	cros_ec_rtc->rtc->ops = &cros_ec_rtc_ops;
 	cros_ec_rtc->rtc->range_max = U32_MAX;
 
-	ret = rtc_register_device(cros_ec_rtc->rtc);
+	ret = devm_rtc_register_device(cros_ec_rtc->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-da9052.c

···
 	rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rtc->rtc->range_max = RTC_TIMESTAMP_END_2063;
 
-	ret = rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-da9063.c

···
 		dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
 			irq_alarm, ret);
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 static struct platform_driver da9063_rtc_driver = {

drivers/rtc/rtc-davinci.c

···
 
 	device_init_wakeup(&pdev->dev, 0);
 
-	return rtc_register_device(davinci_rtc->rtc);
+	return devm_rtc_register_device(davinci_rtc->rtc);
 }
 
 static int __exit davinci_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-digicolor.c

···
 	rtc->rtc_dev->ops = &dc_rtc_ops;
 	rtc->rtc_dev->range_max = U32_MAX;
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 static const struct of_device_id dc_dt_ids[] = {

drivers/rtc/rtc-dm355evm.c

···
 	rtc->ops = &dm355evm_rtc_ops;
 	rtc->range_max = U32_MAX;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 /*

drivers/rtc/rtc-ds1305.c

···
 	ds1305->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
 	ds1305_nvmem_cfg.priv = ds1305;
-	status = rtc_register_device(ds1305->rtc);
+	status = devm_rtc_register_device(ds1305->rtc);
 	if (status)
 		return status;
 

drivers/rtc/rtc-ds1307.c

···
 	if (err)
 		return err;
 
-	err = rtc_register_device(ds1307->rtc);
+	err = devm_rtc_register_device(ds1307->rtc);
 	if (err)
 		return err;
 

drivers/rtc/rtc-ds1343.c

···
 		dev_err(&spi->dev,
 			"unable to create sysfs entries for rtc ds1343\n");
 
-	res = rtc_register_device(priv->rtc);
+	res = devm_rtc_register_device(priv->rtc);
 	if (res)
 		return res;
 

drivers/rtc/rtc-ds1347.c

···
 	rtc->range_min = RTC_TIMESTAMP_BEGIN_0000;
 	rtc->range_max = RTC_TIMESTAMP_END_9999;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct spi_driver ds1347_driver = {

drivers/rtc/rtc-ds1374.c

···
 	ds1374->rtc->ops = &ds1374_rtc_ops;
 	ds1374->rtc->range_max = U32_MAX;
 
-	ret = rtc_register_device(ds1374->rtc);
+	ret = devm_rtc_register_device(ds1374->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ds1511.c

···
 
 	pdata->rtc->ops = &ds1511_rtc_ops;
 
-	ret = rtc_register_device(pdata->rtc);
+	ret = devm_rtc_register_device(pdata->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ds1553.c

···
 
 	pdata->rtc->ops = &ds1553_rtc_ops;
 
-	ret = rtc_register_device(pdata->rtc);
+	ret = devm_rtc_register_device(pdata->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ds1672.c

···
 	rtc->ops = &ds1672_rtc_ops;
 	rtc->range_max = U32_MAX;
 
-	err = rtc_register_device(rtc);
+	err = devm_rtc_register_device(rtc);
 	if (err)
 		return err;
 

drivers/rtc/rtc-ds1685.c

···
 	if (ret)
 		return ret;
 
-	return rtc_register_device(rtc_dev);
+	return devm_rtc_register_device(rtc_dev);
 }
 
 /**

drivers/rtc/rtc-ds1742.c

···
 
 	rtc->ops = &ds1742_rtc_ops;
 
-	ret = rtc_register_device(rtc);
+	ret = devm_rtc_register_device(rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ds2404.c

···
 	chip->rtc->ops = &ds2404_rtc_ops;
 	chip->rtc->range_max = U32_MAX;
 
-	retval = rtc_register_device(chip->rtc);
+	retval = devm_rtc_register_device(chip->rtc);
 	if (retval)
 		return retval;
 

drivers/rtc/rtc-ep93xx.c

···
 	if (err)
 		return err;
 
-	return rtc_register_device(ep93xx_rtc->rtc);
+	return devm_rtc_register_device(ep93xx_rtc->rtc);
 }
 
 static struct platform_driver ep93xx_rtc_driver = {

drivers/rtc/rtc-fsl-ftm-alarm.c

···
 	if (ret)
 		dev_err(&pdev->dev, "failed to enable irq wake\n");
 
-	ret = rtc_register_device(rtc->rtc_dev);
+	ret = devm_rtc_register_device(rtc->rtc_dev);
 	if (ret) {
 		dev_err(&pdev->dev, "can't register rtc device\n");
 		return ret;

drivers/rtc/rtc-ftrtc010.c

···
 	if (unlikely(ret))
 		return ret;
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 static int ftrtc010_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-goldfish.c

···
 	if (err)
 		return err;
 
-	return rtc_register_device(rtcdrv->rtc);
+	return devm_rtc_register_device(rtcdrv->rtc);
 }
 
 static const struct of_device_id goldfish_rtc_of_match[] = {

drivers/rtc/rtc-imx-sc.c

···
 	imx_sc_rtc->range_min = 0;
 	imx_sc_rtc->range_max = U32_MAX;
 
-	ret = rtc_register_device(imx_sc_rtc);
+	ret = devm_rtc_register_device(imx_sc_rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-imxdi.c

···
 	imxdi->rtc->ops = &dryice_rtc_ops;
 	imxdi->rtc->range_max = U32_MAX;
 
-	rc = rtc_register_device(imxdi->rtc);
+	rc = devm_rtc_register_device(imxdi->rtc);
 	if (rc)
 		goto err;
 

drivers/rtc/rtc-isl12026.c

···
 	if (ret)
 		return ret;
 
-	return rtc_register_device(priv->rtc);
+	return devm_rtc_register_device(priv->rtc);
 }
 
 static int isl12026_remove(struct i2c_client *client)

drivers/rtc/rtc-isl1208.c

···
 	if (rc)
 		return rc;
 
-	return rtc_register_device(isl1208->rtc);
+	return devm_rtc_register_device(isl1208->rtc);
 }
 
 static struct i2c_driver isl1208_driver = {

drivers/rtc/rtc-jz4740.c

···
 	/* Each 1 Hz pulse should happen after (rate) ticks */
 	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_REGULATOR, rate - 1);
 
-	ret = rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-lpc32xx.c

···
 	rtc->rtc->ops = &lpc32xx_rtc_ops;
 	rtc->rtc->range_max = U32_MAX;
 
-	err = rtc_register_device(rtc->rtc);
+	err = devm_rtc_register_device(rtc->rtc);
 	if (err)
 		return err;
 

drivers/rtc/rtc-ls1x.c

···
 	rtcdev->range_min = RTC_TIMESTAMP_BEGIN_1900;
 	rtcdev->range_max = RTC_TIMESTAMP_END_2099;
 
-	return rtc_register_device(rtcdev);
+	return devm_rtc_register_device(rtcdev);
 }
 
 static struct platform_driver  ls1x_rtc_driver = {

drivers/rtc/rtc-m41t80.c

···
 		m41t80_sqw_register_clk(m41t80_data);
 #endif
 
-	rc = rtc_register_device(m41t80_data->rtc);
+	rc = devm_rtc_register_device(m41t80_data->rtc);
 	if (rc)
 		return rc;
 

drivers/rtc/rtc-m48t59.c

···
 	if (ret)
 		return ret;
 
-	ret = rtc_register_device(m48t59->rtc);
+	ret = devm_rtc_register_device(m48t59->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-m48t86.c

···
 
 	info->rtc->ops = &m48t86_rtc_ops;
 
-	err = rtc_register_device(info->rtc);
+	err = devm_rtc_register_device(info->rtc);
 	if (err)
 		return err;
 

drivers/rtc/rtc-mc13xxx.c

···
 
 	mc13xxx_unlock(mc13xxx);
 
-	ret = rtc_register_device(priv->rtc);
+	ret = devm_rtc_register_device(priv->rtc);
 	if (ret) {
 		mc13xxx_lock(mc13xxx);
 		goto err_irq_request;

drivers/rtc/rtc-meson-vrtc.c

···
 		return PTR_ERR(vrtc->rtc);
 
 	vrtc->rtc->ops = &meson_vrtc_ops;
-	return rtc_register_device(vrtc->rtc);
+	return devm_rtc_register_device(vrtc->rtc);
 }
 
 static int __maybe_unused meson_vrtc_suspend(struct device *dev)

drivers/rtc/rtc-meson.c

···
 	if (ret)
 		goto out_disable_vdd;
 
-	ret = rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc->rtc);
 	if (ret)
 		goto out_disable_vdd;
 

drivers/rtc/rtc-mpc5121.c

···
 		rtc->rtc->range_max = U32_MAX;
 	}
 
-	err = rtc_register_device(rtc->rtc);
+	err = devm_rtc_register_device(rtc->rtc);
 	if (err)
 		goto out_dispose2;
 

drivers/rtc/rtc-mrst.c

···
 		}
 	}
 
-	retval = rtc_register_device(mrst_rtc.rtc);
+	retval = devm_rtc_register_device(mrst_rtc.rtc);
 	if (retval)
 		goto cleanup0;
 

drivers/rtc/rtc-mt2712.c

···
 	mt2712_rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	mt2712_rtc->rtc->range_max = MT2712_RTC_TIMESTAMP_END_2127;
 
-	return rtc_register_device(mt2712_rtc->rtc);
+	return devm_rtc_register_device(mt2712_rtc->rtc);
 }
 
 #ifdef CONFIG_PM_SLEEP

drivers/rtc/rtc-mt6397.c

···
 
 	rtc->rtc_dev->ops = &mtk_rtc_ops;
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 #ifdef CONFIG_PM_SLEEP

drivers/rtc/rtc-mv.c

···
 	pdata->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	pdata->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	ret = rtc_register_device(pdata->rtc);
+	ret = devm_rtc_register_device(pdata->rtc);
 	if (!ret)
 		return 0;
 out:

drivers/rtc/rtc-mxc.c

···
 			dev_err(&pdev->dev, "failed to enable irq wake\n");
 	}
 
-	ret = rtc_register_device(rtc);
+	ret = devm_rtc_register_device(rtc);
 
 	return ret;
 }

drivers/rtc/rtc-mxc_v2.c

···
 		return ret;
 	}
 
-	ret = rtc_register_device(pdata->rtc);
+	ret = devm_rtc_register_device(pdata->rtc);
 	if (ret < 0)
 		clk_unprepare(pdata->clk);
 

drivers/rtc/rtc-omap.c

···
 		goto err;
 	}
 
-	ret = rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc->rtc);
 	if (ret)
 		goto err;
 

drivers/rtc/rtc-pcap.c

···
 	if (err)
 		return err;
 
-	return rtc_register_device(pcap_rtc->rtc);
+	return devm_rtc_register_device(pcap_rtc->rtc);
 }
 
 static int __exit pcap_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-pcf2123.c

···
 	rtc->range_max = RTC_TIMESTAMP_END_2099;
 	rtc->set_start_time = true;
 
-	ret = rtc_register_device(rtc);
+	ret = devm_rtc_register_device(rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-pcf2127.c

···
 		return ret;
 	}
 
-	return rtc_register_device(pcf2127->rtc);
+	return devm_rtc_register_device(pcf2127->rtc);
 }
 
 #ifdef CONFIG_OF

drivers/rtc/rtc-pcf85063.c

···
 	pcf85063_clkout_register_clk(pcf85063);
 #endif
 
-	return rtc_register_device(pcf85063->rtc);
+	return devm_rtc_register_device(pcf85063->rtc);
 }
 
 #ifdef CONFIG_OF

drivers/rtc/rtc-pcf85363.c

···
 			pcf85363->rtc->ops = &rtc_ops_alarm;
 	}
 
-	ret = rtc_register_device(pcf85363->rtc);
+	ret = devm_rtc_register_device(pcf85363->rtc);
 
 	for (i = 0; i < config->num_nvram; i++) {
 		nvmem_cfg[i].priv = pcf85363;

drivers/rtc/rtc-pcf8563.c

···
 		}
 	}
 
-	err = rtc_register_device(pcf8563->rtc);
+	err = devm_rtc_register_device(pcf8563->rtc);
 	if (err)
 		return err;
 

drivers/rtc/rtc-pic32.c

···
 	pdata->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	pdata->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	ret = rtc_register_device(pdata->rtc);
+	ret = devm_rtc_register_device(pdata->rtc);
 	if (ret)
 		goto err_nortc;
 

drivers/rtc/rtc-pl030.c

···
 	if (ret)
 		goto err_irq;
 
-	ret = rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc->rtc);
 	if (ret)
 		goto err_reg;
 

drivers/rtc/rtc-pl031.c

···
 	ldata->rtc->range_min = vendor->range_min;
 	ldata->rtc->range_max = vendor->range_max;
 
-	ret = rtc_register_device(ldata->rtc);
+	ret = devm_rtc_register_device(ldata->rtc);
 	if (ret)
 		goto out;
 

drivers/rtc/rtc-pm8xxx.c

···
 		return rc;
 	}
 
-	return rtc_register_device(rtc_dd->rtc);
+	return devm_rtc_register_device(rtc_dd->rtc);
 }
 
 #ifdef CONFIG_PM_SLEEP

drivers/rtc/rtc-ps3.c

···
 
 	platform_set_drvdata(dev, rtc);
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct platform_driver ps3_rtc_driver = {

drivers/rtc/rtc-r9701.c

···
 	rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct spi_driver r9701_driver = {

drivers/rtc/rtc-rc5t619.c

···
 		dev_warn(&pdev->dev, "rc5t619 interrupt is disabled\n");
 	}
 
-	return rtc_register_device(rtc->rtc);
+	return devm_rtc_register_device(rtc->rtc);
 }
 
 static struct platform_driver rc5t619_rtc_driver = {

drivers/rtc/rtc-rk808.c

···
 		return ret;
 	}
 
-	return rtc_register_device(rk808_rtc->rtc);
+	return devm_rtc_register_device(rk808_rtc->rtc);
 }
 
 static struct platform_driver rk808_rtc_driver = {

drivers/rtc/rtc-rp5c01.c

···
 	if (error)
 		return error;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct platform_driver rp5c01_rtc_driver = {

drivers/rtc/rtc-rs5c348.c

···
 
 	rtc->ops = &rs5c348_rtc_ops;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct spi_driver rs5c348_driver = {

drivers/rtc/rtc-rv3028.c

···
 	rv3028->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rv3028->rtc->range_max = RTC_TIMESTAMP_END_2099;
 	rv3028->rtc->ops = &rv3028_rtc_ops;
-	ret = rtc_register_device(rv3028->rtc);
+	ret = devm_rtc_register_device(rv3028->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-rv3029c2.c

···
 	rv3029->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rv3029->rtc->range_max = RTC_TIMESTAMP_END_2079;
 
-	rc = rtc_register_device(rv3029->rtc);
+	rc = devm_rtc_register_device(rv3029->rtc);
 	if (rc)
 		return rc;
 

drivers/rtc/rtc-rv3032.c

···
 	rv3032->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rv3032->rtc->range_max = RTC_TIMESTAMP_END_2099;
 	rv3032->rtc->ops = &rv3032_rtc_ops;
-	ret = rtc_register_device(rv3032->rtc);
+	ret = devm_rtc_register_device(rv3032->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-rv8803.c

···
 	rv8803->rtc->ops = &rv8803_rtc_ops;
 	rv8803->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rv8803->rtc->range_max = RTC_TIMESTAMP_END_2099;
-	err = rtc_register_device(rv8803->rtc);
+	err = devm_rtc_register_device(rv8803->rtc);
 	if (err)
 		return err;
 

drivers/rtc/rtc-rx8010.c

···
 	rx8010->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rx8010->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	return rtc_register_device(rx8010->rtc);
+	return devm_rtc_register_device(rx8010->rtc);
 }
 
 static struct i2c_driver rx8010_driver = {

drivers/rtc/rtc-rx8581.c

···
 	rx8581->rtc->start_secs = 0;
 	rx8581->rtc->set_start_time = true;
 
-	ret = rtc_register_device(rx8581->rtc);
+	ret = devm_rtc_register_device(rx8581->rtc);
 
 	for (i = 0; i < config->num_nvram; i++) {
 		nvmem_cfg[i].priv = rx8581;

drivers/rtc/rtc-s35390a.c

···
 	if (status1 & S35390A_FLAG_INT2)
 		rtc_update_irq(s35390a->rtc, 1, RTC_AF);
 
-	return rtc_register_device(s35390a->rtc);
+	return devm_rtc_register_device(s35390a->rtc);
 }
 
 static struct i2c_driver s35390a_driver = {

drivers/rtc/rtc-sa1100.c

···
 	info->rtc->max_user_freq = RTC_FREQ;
 	info->rtc->range_max = U32_MAX;
 
-	ret = rtc_register_device(info->rtc);
+	ret = devm_rtc_register_device(info->rtc);
 	if (ret) {
 		clk_disable_unprepare(info->clk);
 		return ret;

drivers/rtc/rtc-sc27xx.c

···
 	rtc->rtc->ops = &sprd_rtc_ops;
 	rtc->rtc->range_min = 0;
 	rtc->rtc->range_max = 5662310399LL;
-	ret = rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc->rtc);
 	if (ret) {
 		device_init_wakeup(&pdev->dev, 0);
 		return ret;

drivers/rtc/rtc-sd3078.c

···
 	sd3078->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	sd3078->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	ret = rtc_register_device(sd3078->rtc);
+	ret = devm_rtc_register_device(sd3078->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-sh.c

···
 		rtc->rtc_dev->range_max = mktime64(2098, 12, 31, 23, 59, 59);
 	}
 
-	ret = rtc_register_device(rtc->rtc_dev);
+	ret = devm_rtc_register_device(rtc->rtc_dev);
 	if (ret)
 		goto err_unmap;
 

drivers/rtc/rtc-sirfsoc.c

···
 		return err;
 	}
 
-	return rtc_register_device(rtcdrv->rtc);
+	return devm_rtc_register_device(rtcdrv->rtc);
 }
 
 #ifdef CONFIG_PM_SLEEP

drivers/rtc/rtc-snvs.c

···
 	data->rtc->ops = &snvs_rtc_ops;
 	data->rtc->range_max = U32_MAX;
 
-	return rtc_register_device(data->rtc);
+	return devm_rtc_register_device(data->rtc);
 }
 
 static int __maybe_unused snvs_rtc_suspend_noirq(struct device *dev)

drivers/rtc/rtc-st-lpc.c

···
 	rtc->rtc_dev->range_max = U64_MAX;
 	do_div(rtc->rtc_dev->range_max, rtc->clkrate);
 
-	ret = rtc_register_device(rtc->rtc_dev);
+	ret = devm_rtc_register_device(rtc->rtc_dev);
 	if (ret) {
 		clk_disable_unprepare(rtc->clk);
 		return ret;

drivers/rtc/rtc-starfire.c

···
 
 	platform_set_drvdata(pdev, rtc);
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct platform_driver starfire_rtc_driver = {

drivers/rtc/rtc-stk17ta8.c

···
 	if (ret)
 		return ret;
 
-	return rtc_register_device(pdata->rtc);
+	return devm_rtc_register_device(pdata->rtc);
 }
 
 /* work with hotplug and coldplug */

drivers/rtc/rtc-stmp3xxx.c

···
 	rtc_data->rtc->ops = &stmp3xxx_rtc_ops;
 	rtc_data->rtc->range_max = U32_MAX;
 
-	err = rtc_register_device(rtc_data->rtc);
+	err = devm_rtc_register_device(rtc_data->rtc);
 	if (err)
 		return err;
 

drivers/rtc/rtc-sun4v.c

···
 	rtc->range_max = U64_MAX;
 	platform_set_drvdata(pdev, rtc);
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct platform_driver sun4v_rtc_driver = {

drivers/rtc/rtc-sun6i.c

···
 	chip->rtc->ops = &sun6i_rtc_ops;
 	chip->rtc->range_max = 2019686399LL; /* 2033-12-31 23:59:59 */
 
-	ret = rtc_register_device(chip->rtc);
+	ret = devm_rtc_register_device(chip->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-sunxi.c

···
 
 	chip->rtc->ops = &sunxi_rtc_ops;
 
-	return rtc_register_device(chip->rtc);
+	return devm_rtc_register_device(chip->rtc);
 }
 
 static struct platform_driver sunxi_rtc_driver = {

drivers/rtc/rtc-tegra.c

···
 		goto disable_clk;
 	}
 
-	ret = rtc_register_device(info->rtc);
+	ret = devm_rtc_register_device(info->rtc);
 	if (ret)
 		goto disable_clk;
 

drivers/rtc/rtc-test.c

···
 	timer_setup(&rtd->alarm, test_rtc_alarm_handler, 0);
 	rtd->alarm.expires = 0;
 
-	return rtc_register_device(rtd->rtc);
+	return devm_rtc_register_device(rtd->rtc);
 }
 
 static struct platform_driver test_driver = {

drivers/rtc/rtc-tps6586x.c

···
 		goto fail_rtc_register;
 	}
 
-	ret = rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc->rtc);
 	if (ret)
 		goto fail_rtc_register;
 

drivers/rtc/rtc-tps65910.c

···
 	tps_rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	tps_rtc->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	return rtc_register_device(tps_rtc->rtc);
+	return devm_rtc_register_device(tps_rtc->rtc);
 }
 
 #ifdef CONFIG_PM_SLEEP

drivers/rtc/rtc-tx4939.c

···
 	if (ret)
 		return ret;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static int __exit tx4939_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-vr41xx.c

···
 
 	dev_info(&pdev->dev, "Real Time Clock of NEC VR4100 series\n");
 
-	retval = rtc_register_device(rtc);
+	retval = devm_rtc_register_device(rtc);
 	if (retval)
 		goto err_iounmap_all;
 

drivers/rtc/rtc-vt8500.c

···
 		return ret;
 	}
 
-	return rtc_register_device(vt8500_rtc->rtc);
+	return devm_rtc_register_device(vt8500_rtc->rtc);
 }
 
 static int vt8500_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-wilco-ec.c

···
 	rtc->range_max = RTC_TIMESTAMP_END_2099;
 	rtc->owner = THIS_MODULE;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct platform_driver wilco_ec_rtc_driver = {

drivers/rtc/rtc-wm831x.c

···
 	wm831x_rtc->rtc->ops = &wm831x_rtc_ops;
 	wm831x_rtc->rtc->range_max = U32_MAX;
 
-	ret = rtc_register_device(wm831x_rtc->rtc);
+	ret = devm_rtc_register_device(wm831x_rtc->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-xgene.c

···
 	pdata->rtc->ops = &xgene_rtc_ops;
 	pdata->rtc->range_max = U32_MAX;
 
-	ret = rtc_register_device(pdata->rtc);
+	ret = devm_rtc_register_device(pdata->rtc);
 	if (ret) {
 		clk_disable_unprepare(pdata->clk);
 		return ret;

drivers/rtc/rtc-zynqmp.c

···
 
 	device_init_wakeup(&pdev->dev, 1);
 
-	return rtc_register_device(xrtcdev->rtc);
+	return devm_rtc_register_device(xrtcdev->rtc);
 }
 
 static int xlnx_rtc_remove(struct platform_device *pdev)

drivers/rtc/sysfs.c

···
 	size_t old_cnt = 0, add_cnt = 0, new_cnt;
 	const struct attribute_group **groups, **old;
 
-	if (rtc->registered)
-		return -EINVAL;
 	if (!grps)
 		return -EINVAL;
 

include/linux/rtc.h

···
 	 */
 	long set_offset_nsec;
 
-	bool registered;
-
 	time64_t range_min;
 	timeu64_t range_max;
 	time64_t start_secs;
···
 					const struct rtc_class_ops *ops,
 					struct module *owner);
 struct rtc_device *devm_rtc_allocate_device(struct device *dev);
-int __rtc_register_device(struct module *owner, struct rtc_device *rtc);
+int __devm_rtc_register_device(struct module *owner, struct rtc_device *rtc);
 
 extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
 extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
···
 	return false;
 }
 
-#define rtc_register_device(device) \
-	__rtc_register_device(THIS_MODULE, device)
+#define devm_rtc_register_device(device) \
+	__devm_rtc_register_device(THIS_MODULE, device)
 
 #ifdef CONFIG_RTC_HCTOSYS_DEVICE
 extern int rtc_hctosys_ret;