[PATCH 1/3] rtc: rs5c348: remove useless label

[PATCH 1/3] rtc: rs5c348: remove useless label

[Alexandre Belloni]

Since commit 8fb1ecb36f7e ("rtc: rtc-rs5c348: use devm_*() functions") the
kfree_exit label simply returns ret.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
 drivers/rtc/rtc-rs5c348.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/rtc/rtc-rs5c348.c b/drivers/rtc/rtc-rs5c348.c
index f2de8b17e7e3..aeb14fc0175d 100644
--- a/drivers/rtc/rtc-rs5c348.c
+++ b/drivers/rtc/rtc-rs5c348.c
@@ -161,7 +161,7 @@ static int rs5c348_probe(struct spi_device *spi)
 	ret = spi_w8r8(spi, RS5C348_CMD_R(RS5C348_REG_SECS));
 	if (ret < 0 || (ret & 0x80)) {
 		dev_err(&spi->dev, "not found.\n");
-		goto kfree_exit;
+		return ret;
 	}
 
 	dev_info(&spi->dev, "spiclk %u KHz.\n",
@@ -170,7 +170,7 @@ static int rs5c348_probe(struct spi_device *spi)
 	/* turn RTC on if it was not on */
 	ret = spi_w8r8(spi, RS5C348_CMD_R(RS5C348_REG_CTL2));
 	if (ret < 0)
-		goto kfree_exit;
+		return ret;
 	if (ret & (RS5C348_BIT_XSTP | RS5C348_BIT_VDET)) {
 		u8 buf[2];
 		struct rtc_time tm;
@@ -181,33 +181,29 @@ static int rs5c348_probe(struct spi_device *spi)
 		rtc_time_to_tm(0, &tm);	/* 1970/1/1 */
 		ret = rs5c348_rtc_set_time(&spi->dev, &tm);
 		if (ret < 0)
-			goto kfree_exit;
+			return ret;
 		buf[0] = RS5C348_CMD_W(RS5C348_REG_CTL2);
 		buf[1] = 0;
 		ret = spi_write_then_read(spi, buf, sizeof(buf), NULL, 0);
 		if (ret < 0)
-			goto kfree_exit;
+			return ret;
 	}
 
 	ret = spi_w8r8(spi, RS5C348_CMD_R(RS5C348_REG_CTL1));
 	if (ret < 0)
-		goto kfree_exit;
+		return ret;
 	if (ret & RS5C348_BIT_24H)
 		pdata->rtc_24h = 1;
 
 	rtc = devm_rtc_device_register(&spi->dev, rs5c348_driver.driver.name,
 				  &rs5c348_rtc_ops, THIS_MODULE);
 
-	if (IS_ERR(rtc)) {
-		ret = PTR_ERR(rtc);
-		goto kfree_exit;
-	}
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
 
 	pdata->rtc = rtc;
 
 	return 0;
- kfree_exit:
-	return ret;
 }
 
 static struct spi_driver rs5c348_driver = {
-- 
2.19.0

[PATCH 2/3] rtc: rs5c348: remove forward declaration

[Alexandre Belloni]

The name passed to devm_rtc_device_register is now unused. anyway, switch
to devm_rtc_allocate_device to avoid forward declaring rs5c348_driver.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
 drivers/rtc/rtc-rs5c348.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/rtc/rtc-rs5c348.c b/drivers/rtc/rtc-rs5c348.c
index aeb14fc0175d..7b9c7dc5b309 100644
--- a/drivers/rtc/rtc-rs5c348.c
+++ b/drivers/rtc/rtc-rs5c348.c
@@ -143,8 +143,6 @@ static const struct rtc_class_ops rs5c348_rtc_ops = {
 	.set_time	= rs5c348_rtc_set_time,
 };
 
-static struct spi_driver rs5c348_driver;
-
 static int rs5c348_probe(struct spi_device *spi)
 {
 	int ret;
@@ -195,15 +193,15 @@ static int rs5c348_probe(struct spi_device *spi)
 	if (ret & RS5C348_BIT_24H)
 		pdata->rtc_24h = 1;
 
-	rtc = devm_rtc_device_register(&spi->dev, rs5c348_driver.driver.name,
-				  &rs5c348_rtc_ops, THIS_MODULE);
-
+	rtc = devm_rtc_allocate_device(&spi->dev);
 	if (IS_ERR(rtc))
 		return PTR_ERR(rtc);
 
 	pdata->rtc = rtc;
 
-	return 0;
+	rtc->ops = &rs5c348_rtc_ops;
+
+	return rtc_register_device(rtc);
 }
 
 static struct spi_driver rs5c348_driver = {
-- 
2.19.0

[PATCH 3/3] rtc: rs5c348: report error when time is invalid

[Alexandre Belloni]

Instead of resetting the RTC to an bogus valid time, let userspace know
that the time is invalid when XSTP is set. Reset XSTP when setting the time
again.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
 drivers/rtc/rtc-rs5c348.c | 43 +++++++++++++++++++--------------------
 1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/drivers/rtc/rtc-rs5c348.c b/drivers/rtc/rtc-rs5c348.c
index 7b9c7dc5b309..6582be707bd0 100644
--- a/drivers/rtc/rtc-rs5c348.c
+++ b/drivers/rtc/rtc-rs5c348.c
@@ -66,6 +66,17 @@ rs5c348_rtc_set_time(struct device *dev, struct rtc_time *tm)
 	u8 txbuf[5+7], *txp;
 	int ret;
 
+	ret = spi_w8r8(spi, RS5C348_CMD_R(RS5C348_REG_CTL2));
+	if (ret < 0)
+		return ret;
+	if (ret & RS5C348_BIT_XSTP) {
+		txbuf[0] = RS5C348_CMD_W(RS5C348_REG_CTL2);
+		txbuf[1] = 0;
+		ret = spi_write_then_read(spi, txbuf, 2, NULL, 0);
+		if (ret < 0)
+			return ret;
+	}
+
 	/* Transfer 5 bytes before writing SEC.  This gives 31us for carry. */
 	txp = txbuf;
 	txbuf[0] = RS5C348_CMD_R(RS5C348_REG_CTL2); /* cmd, ctl2 */
@@ -102,6 +113,16 @@ rs5c348_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	u8 txbuf[5], rxbuf[7];
 	int ret;
 
+	ret = spi_w8r8(spi, RS5C348_CMD_R(RS5C348_REG_CTL2));
+	if (ret < 0)
+		return ret;
+	if (ret & RS5C348_BIT_VDET)
+		dev_warn(&spi->dev, "voltage-low detected.\n");
+	if (ret & RS5C348_BIT_XSTP) {
+		dev_warn(&spi->dev, "oscillator-stop detected.\n");
+		return -EINVAL;
+	}
+
 	/* Transfer 5 byte befores reading SEC.  This gives 31us for carry. */
 	txbuf[0] = RS5C348_CMD_R(RS5C348_REG_CTL2); /* cmd, ctl2 */
 	txbuf[1] = 0;	/* dummy */
@@ -165,28 +186,6 @@ static int rs5c348_probe(struct spi_device *spi)
 	dev_info(&spi->dev, "spiclk %u KHz.\n",
 		 (spi->max_speed_hz + 500) / 1000);
 
-	/* turn RTC on if it was not on */
-	ret = spi_w8r8(spi, RS5C348_CMD_R(RS5C348_REG_CTL2));
-	if (ret < 0)
-		return ret;
-	if (ret & (RS5C348_BIT_XSTP | RS5C348_BIT_VDET)) {
-		u8 buf[2];
-		struct rtc_time tm;
-		if (ret & RS5C348_BIT_VDET)
-			dev_warn(&spi->dev, "voltage-low detected.\n");
-		if (ret & RS5C348_BIT_XSTP)
-			dev_warn(&spi->dev, "oscillator-stop detected.\n");
-		rtc_time_to_tm(0, &tm);	/* 1970/1/1 */
-		ret = rs5c348_rtc_set_time(&spi->dev, &tm);
-		if (ret < 0)
-			return ret;
-		buf[0] = RS5C348_CMD_W(RS5C348_REG_CTL2);
-		buf[1] = 0;
-		ret = spi_write_then_read(spi, buf, sizeof(buf), NULL, 0);
-		if (ret < 0)
-			return ret;
-	}
-
 	ret = spi_w8r8(spi, RS5C348_CMD_R(RS5C348_REG_CTL1));
 	if (ret < 0)
 		return ret;
-- 
2.19.0