rtc: s35390a: clarify INT2 pin output modes

Fix the INT2 mode mask to not include the "TEST" flag. Furthermore
remove the not needed reversion of bits when parsing the INT2 modes.
Instead reverse the INT2_MODE defines to match the bit order from the
datasheet.

Additionally mention the flag names from the datasheet for the different
modes in the comments.
Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

drivers/rtc/rtc-s35390a.c

@@ -45,12 +45,13 @@
 /* flag for STATUS2 */
 #define S35390A_FLAG_TEST	0x01
 
-#define S35390A_INT2_MODE_MASK		0xF0
-
+/* INT2 pin output mode */
+#define S35390A_INT2_MODE_MASK		0x0E
 #define S35390A_INT2_MODE_NOINTR	0x00
-#define S35390A_INT2_MODE_FREQ		0x10
-#define S35390A_INT2_MODE_ALARM		0x40
-#define S35390A_INT2_MODE_PMIN_EDG	0x20
+#define S35390A_INT2_MODE_ALARM		BIT(1) /* INT2AE */
+#define S35390A_INT2_MODE_PMIN_EDG	BIT(2) /* INT2ME */
+#define S35390A_INT2_MODE_FREQ		BIT(3) /* INT2FE */
+#define S35390A_INT2_MODE_PMIN		(BIT(3) | BIT(2)) /* INT2FE | INT2ME */
 
 static const struct i2c_device_id s35390a_id[] = {
 	{ "s35390a", 0 },
@@ -303,9 +304,6 @@ static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	else
 		sts = S35390A_INT2_MODE_NOINTR;
 
-	/* This chip expects the bits of each byte to be in reverse order */
-	sts = bitrev8(sts);
-
 	/* set interupt mode*/
 	err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
 	if (err < 0)
@@ -343,7 +341,7 @@ static int s35390a_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	if (err < 0)
 		return err;
 
-	if ((bitrev8(sts) & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
+	if ((sts & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
 		/*
 		 * When the alarm isn't enabled, the register to configure
 		 * the alarm time isn't accessible.