rtc: m48t59: remove m48t02_rtc_ops

Clear RTC_FEATURE_ALARM to signal that alarms are not available instead of
having a supplementary struct rtc_class_ops without alarm callbacks.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210110231752.1418816-7-alexandre.belloni@bootlin.com

drivers/rtc/rtc-m48t59.c

@@ -313,11 +313,6 @@ static const struct rtc_class_ops m48t59_rtc_ops = {
 	.alarm_irq_enable = m48t59_rtc_alarm_irq_enable,
 };
 
-static const struct rtc_class_ops m48t02_rtc_ops = {
-	.read_time	= m48t59_rtc_read_time,
-	.set_time	= m48t59_rtc_set_time,
-};
-
 static int m48t59_nvram_read(void *priv, unsigned int offset, void *val,
 			     size_t size)
 {
@@ -366,7 +361,6 @@ static int m48t59_rtc_probe(struct platform_device *pdev)
 	struct m48t59_private *m48t59 = NULL;
 	struct resource *res;
 	int ret = -ENOMEM;
-	const struct rtc_class_ops *ops;
 	struct nvmem_config nvmem_cfg = {
 		.name = "m48t59-",
 		.word_size = 1,
@@ -438,17 +432,21 @@ static int m48t59_rtc_probe(struct platform_device *pdev)
 		if (ret)
 			return ret;
 	}
+
+	m48t59->rtc = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(m48t59->rtc))
+		return PTR_ERR(m48t59->rtc);
+
 	switch (pdata->type) {
 	case M48T59RTC_TYPE_M48T59:
-		ops = &m48t59_rtc_ops;
 		pdata->offset = 0x1ff0;
 		break;
 	case M48T59RTC_TYPE_M48T02:
-		ops = &m48t02_rtc_ops;
+		clear_bit(RTC_FEATURE_ALARM, m48t59->rtc->features);
 		pdata->offset = 0x7f0;
 		break;
 	case M48T59RTC_TYPE_M48T08:
-		ops = &m48t02_rtc_ops;
+		clear_bit(RTC_FEATURE_ALARM, m48t59->rtc->features);
 		pdata->offset = 0x1ff0;
 		break;
 	default:
@@ -459,11 +457,7 @@ static int m48t59_rtc_probe(struct platform_device *pdev)
 	spin_lock_init(&m48t59->lock);
 	platform_set_drvdata(pdev, m48t59);
 
-	m48t59->rtc = devm_rtc_allocate_device(&pdev->dev);
-	if (IS_ERR(m48t59->rtc))
-		return PTR_ERR(m48t59->rtc);
-
-	m48t59->rtc->ops = ops;
+	m48t59->rtc->ops = &m48t59_rtc_ops;
 
 	nvmem_cfg.size = pdata->offset;
 	ret = devm_rtc_nvmem_register(m48t59->rtc, &nvmem_cfg);