rtc: nvmem: remove nvram ABI

The nvram sysfs attributes have been deprecated at least since v4.13, more
than 3 years ago and nobody ever complained about the deprecation warning.

Remove the sysfs attributes now.

[Bartosz: remove the declaration of rtc_nvmem_unregister()]
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20201109163409.24301-5-brgl@bgdev.pl

drivers/rtc/class.c

@@ -339,8 +339,6 @@ static void devm_rtc_release_device(struct device *dev, void *res)
 {
 	struct rtc_device *rtc = *(struct rtc_device **)res;
 
-	rtc_nvmem_unregister(rtc);
-
 	if (rtc->registered)
 		rtc_device_unregister(rtc);
 	else

drivers/rtc/nvmem.c

@@ -9,74 +9,7 @@
 #include <linux/types.h>
 #include <linux/nvmem-consumer.h>
 #include <linux/rtc.h>
-#include <linux/slab.h>
-#include <linux/sysfs.h>
 
-/*
- * Deprecated ABI compatibility, this should be removed at some point
- */
-
-static const char nvram_warning[] = "Deprecated ABI, please use nvmem";
-
-static ssize_t
-rtc_nvram_read(struct file *filp, struct kobject *kobj,
-	       struct bin_attribute *attr,
-	       char *buf, loff_t off, size_t count)
-{
-	dev_warn_once(kobj_to_dev(kobj), nvram_warning);
-
-	return nvmem_device_read(attr->private, off, count, buf);
-}
-
-static ssize_t
-rtc_nvram_write(struct file *filp, struct kobject *kobj,
-		struct bin_attribute *attr,
-		char *buf, loff_t off, size_t count)
-{
-	dev_warn_once(kobj_to_dev(kobj), nvram_warning);
-
-	return nvmem_device_write(attr->private, off, count, buf);
-}
-
-static int rtc_nvram_register(struct rtc_device *rtc,
-			      struct nvmem_device *nvmem, size_t size)
-{
-	int err;
-
-	rtc->nvram = kzalloc(sizeof(*rtc->nvram), GFP_KERNEL);
-	if (!rtc->nvram)
-		return -ENOMEM;
-
-	rtc->nvram->attr.name = "nvram";
-	rtc->nvram->attr.mode = 0644;
-	rtc->nvram->private = nvmem;
-
-	sysfs_bin_attr_init(rtc->nvram);
-
-	rtc->nvram->read = rtc_nvram_read;
-	rtc->nvram->write = rtc_nvram_write;
-	rtc->nvram->size = size;
-
-	err = sysfs_create_bin_file(&rtc->dev.parent->kobj,
-				    rtc->nvram);
-	if (err) {
-		kfree(rtc->nvram);
-		rtc->nvram = NULL;
-	}
-
-	return err;
-}
-
-static void rtc_nvram_unregister(struct rtc_device *rtc)
-{
-	sysfs_remove_bin_file(&rtc->dev.parent->kobj, rtc->nvram);
-	kfree(rtc->nvram);
-	rtc->nvram = NULL;
-}
-
-/*
- * New ABI, uses nvmem
- */
 int rtc_nvmem_register(struct rtc_device *rtc,
 		       struct nvmem_config *nvmem_config)
 {
@@ -88,20 +21,7 @@ int rtc_nvmem_register(struct rtc_device *rtc,
 	nvmem_config->dev = rtc->dev.parent;
 	nvmem_config->owner = rtc->owner;
 	nvmem = devm_nvmem_register(rtc->dev.parent, nvmem_config);
-	if (IS_ERR(nvmem))
-		return PTR_ERR(nvmem);
-
-	/* Register the old ABI */
-	if (rtc->nvram_old_abi)
-		rtc_nvram_register(rtc, nvmem, nvmem_config->size);
 
-	return 0;
+	return PTR_ERR_OR_ZERO(nvmem);
 }
 EXPORT_SYMBOL_GPL(rtc_nvmem_register);
-
-void rtc_nvmem_unregister(struct rtc_device *rtc)
-{
-	/* unregister the old ABI */
-	if (rtc->nvram)
-		rtc_nvram_unregister(rtc);
-}

drivers/rtc/rtc-cmos.c

@@ -863,7 +863,6 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
 		cmos_rtc.rtc->ops = &cmos_rtc_ops_no_alarm;
 	}
 
-	cmos_rtc.rtc->nvram_old_abi = true;
 	retval = rtc_register_device(cmos_rtc.rtc);
 	if (retval)
 		goto cleanup2;

drivers/rtc/rtc-ds1305.c

@@ -694,7 +694,6 @@ static int ds1305_probe(struct spi_device *spi)
 	ds1305->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
 	ds1305_nvmem_cfg.priv = ds1305;
-	ds1305->rtc->nvram_old_abi = true;
 	status = rtc_register_device(ds1305->rtc);
 	if (status)
 		return status;

drivers/rtc/rtc-ds1307.c

@@ -2016,7 +2016,6 @@ static int ds1307_probe(struct i2c_client *client,
 			.priv = ds1307,
 		};
 
-		ds1307->rtc->nvram_old_abi = true;
 		rtc_nvmem_register(ds1307->rtc, &nvmem_cfg);
 	}
 

drivers/rtc/rtc-ds1343.c

@@ -399,7 +399,6 @@ static int ds1343_probe(struct spi_device *spi)
 	if (IS_ERR(priv->rtc))
 		return PTR_ERR(priv->rtc);
 
-	priv->rtc->nvram_old_abi = true;
 	priv->rtc->ops = &ds1343_rtc_ops;
 	priv->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	priv->rtc->range_max = RTC_TIMESTAMP_END_2099;

drivers/rtc/rtc-ds1511.c

@@ -466,8 +466,6 @@ static int ds1511_rtc_probe(struct platform_device *pdev)
 
 	pdata->rtc->ops = &ds1511_rtc_ops;
 
-	pdata->rtc->nvram_old_abi = true;
-
 	ret = rtc_register_device(pdata->rtc);
 	if (ret)
 		return ret;

drivers/rtc/rtc-ds1553.c

@@ -294,7 +294,6 @@ static int ds1553_rtc_probe(struct platform_device *pdev)
 		return PTR_ERR(pdata->rtc);
 
 	pdata->rtc->ops = &ds1553_rtc_ops;
-	pdata->rtc->nvram_old_abi = true;
 
 	ret = rtc_register_device(pdata->rtc);
 	if (ret)

drivers/rtc/rtc-ds1685.c

@@ -1316,7 +1316,6 @@ ds1685_rtc_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	rtc_dev->nvram_old_abi = true;
 	nvmem_cfg.priv = rtc;
 	ret = rtc_nvmem_register(rtc_dev, &nvmem_cfg);
 	if (ret)

drivers/rtc/rtc-ds1742.c

@@ -190,7 +190,6 @@ static int ds1742_rtc_probe(struct platform_device *pdev)
 		return PTR_ERR(rtc);
 
 	rtc->ops = &ds1742_rtc_ops;
-	rtc->nvram_old_abi = true;
 
 	ret = rtc_register_device(rtc);
 	if (ret)

drivers/rtc/rtc-m48t59.c

@@ -463,7 +463,6 @@ static int m48t59_rtc_probe(struct platform_device *pdev)
 	if (IS_ERR(m48t59->rtc))
 		return PTR_ERR(m48t59->rtc);
 
-	m48t59->rtc->nvram_old_abi = true;
 	m48t59->rtc->ops = ops;
 
 	nvmem_cfg.size = pdata->offset;

drivers/rtc/rtc-m48t86.c

@@ -254,7 +254,6 @@ static int m48t86_rtc_probe(struct platform_device *pdev)
 		return PTR_ERR(info->rtc);
 
 	info->rtc->ops = &m48t86_rtc_ops;
-	info->rtc->nvram_old_abi = true;
 
 	err = rtc_register_device(info->rtc);
 	if (err)

drivers/rtc/rtc-rp5c01.c

@@ -251,7 +251,6 @@ static int __init rp5c01_rtc_probe(struct platform_device *dev)
 		return PTR_ERR(rtc);
 
 	rtc->ops = &rp5c01_rtc_ops;
-	rtc->nvram_old_abi = true;
 
 	priv->rtc = rtc;
 

drivers/rtc/rtc-rv8803.c

@@ -585,7 +585,6 @@ static int rv8803_probe(struct i2c_client *client,
 	}
 
 	rv8803->rtc->ops = &rv8803_rtc_ops;
-	rv8803->rtc->nvram_old_abi = true;
 	rv8803->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rv8803->rtc->range_max = RTC_TIMESTAMP_END_2099;
 	err = rtc_register_device(rv8803->rtc);

drivers/rtc/rtc-stk17ta8.c

@@ -311,7 +311,6 @@ static int stk17ta8_rtc_probe(struct platform_device *pdev)
 		return PTR_ERR(pdata->rtc);
 
 	pdata->rtc->ops = &stk17ta8_rtc_ops;
-	pdata->rtc->nvram_old_abi = true;
 
 	nvmem_cfg.priv = pdata;
 	ret = rtc_nvmem_register(pdata->rtc, &nvmem_cfg);

drivers/rtc/rtc-tx4939.c

@@ -266,7 +266,6 @@ static int __init tx4939_rtc_probe(struct platform_device *pdev)
 		return PTR_ERR(rtc);
 
 	rtc->ops = &tx4939_rtc_ops;
-	rtc->nvram_old_abi = true;
 	rtc->range_max = U32_MAX;
 
 	pdata->rtc = rtc;

include/linux/rtc.h

@@ -120,10 +120,6 @@ struct rtc_device {
 
 	bool registered;
 
-	/* Old ABI support */
-	bool nvram_old_abi;
-	struct bin_attribute *nvram;
-
 	time64_t range_min;
 	timeu64_t range_max;
 	time64_t start_secs;
@@ -250,14 +246,12 @@ extern int rtc_hctosys_ret;
 #ifdef CONFIG_RTC_NVMEM
 int rtc_nvmem_register(struct rtc_device *rtc,
 		       struct nvmem_config *nvmem_config);
-void rtc_nvmem_unregister(struct rtc_device *rtc);
 #else
 static inline int rtc_nvmem_register(struct rtc_device *rtc,
 				     struct nvmem_config *nvmem_config)
 {
 	return 0;
 }
-static inline void rtc_nvmem_unregister(struct rtc_device *rtc) {}
 #endif
 
 #ifdef CONFIG_RTC_INTF_SYSFS