[PATCH v2] rtc: pcf85363: Add error checking to regmap calls in probe()

[Cosmo Chou <chou.cosmo@gmail.com>]

The probe() function ignores errors returned by regmap operations.
If an I2C transport error occurs (e.g., -ENXIO), the driver continues
probing and may register a non-functional RTC device.

Propagate errors from all unchecked regmap calls in probe() using
dev_err_probe().

Fixes: fd9a6a13949a ("rtc: pcf85363: add support for the quartz-load-femtofarads property")
Signed-off-by: Cosmo Chou <chou.cosmo@gmail.com>
---
Changes in v2 [1]:
- Update commit message to reflect the new scope of the fix
- Add error checking to all remaining regmap calls in probe()
  (regmap_write to CTRL_FLAGS and regmap_update_bits to CTRL_PIN_IO)

[1] https://lore.kernel.org/linux-rtc/20260716125142.1801599-1-chou.cosmo@gmail.com/

 drivers/rtc/rtc-pcf85363.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/rtc/rtc-pcf85363.c b/drivers/rtc/rtc-pcf85363.c
index 540042b9eec8..ccc7834e5759 100644
--- a/drivers/rtc/rtc-pcf85363.c
+++ b/drivers/rtc/rtc-pcf85363.c
@@ -426,8 +426,8 @@ static int pcf85363_probe(struct i2c_client *client)
 
 	err = pcf85363_load_capacitance(pcf85363, client->dev.of_node);
 	if (err < 0)
-		dev_warn(&client->dev, "failed to set xtal load capacitance: %d",
-			 err);
+		return dev_err_probe(&client->dev, err,
+				     "failed to set xtal load capacitance\n");
 
 	pcf85363->rtc->ops = &rtc_ops;
 	pcf85363->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
@@ -436,9 +436,16 @@ static int pcf85363_probe(struct i2c_client *client)
 	wakeup_source = device_property_read_bool(&client->dev,
 						  "wakeup-source");
 	if (client->irq > 0 || wakeup_source) {
-		regmap_write(pcf85363->regmap, CTRL_FLAGS, 0);
-		regmap_update_bits(pcf85363->regmap, CTRL_PIN_IO,
-				   PIN_IO_INTAPM, PIN_IO_INTA_OUT);
+		err = regmap_write(pcf85363->regmap, CTRL_FLAGS, 0);
+		if (err)
+			return dev_err_probe(&client->dev, err,
+					     "failed to clear flags\n");
+
+		err = regmap_update_bits(pcf85363->regmap, CTRL_PIN_IO,
+					 PIN_IO_INTAPM, PIN_IO_INTA_OUT);
+		if (err)
+			return dev_err_probe(&client->dev, err,
+					     "failed to set interrupt pin mode\n");
 	}
 
 	if (client->irq > 0) {
-- 
2.43.0