[PATCH 3/3] rtc: s35390a: make use of interrupt signal 1
From: Markus Probst
Date: Tue Jun 30 2026 - 15:27:37 EST
If configured, use output pin for interrupt signal 1 for the wake alarm.
Successfully Tested on a Synology DS923+.
Signed-off-by: Markus Probst <markus.probst@xxxxxxxxx>
---
drivers/rtc/rtc-s35390a.c | 61 +++++++++++++++++++++++++++++++++++++----------
1 file changed, 49 insertions(+), 12 deletions(-)
diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c
index 4cfe7034c516..6875bf039cbf 100644
--- a/drivers/rtc/rtc-s35390a.c
+++ b/drivers/rtc/rtc-s35390a.c
@@ -12,11 +12,13 @@
#include <linux/bcd.h>
#include <linux/slab.h>
#include <linux/delay.h>
+#include <dt-bindings/rtc/s35390a.h>
#define S35390A_CMD_STATUS1 0
#define S35390A_CMD_STATUS2 1
#define S35390A_CMD_TIME1 2
#define S35390A_CMD_TIME2 3
+#define S35390A_CMD_INT1_REG1 4
#define S35390A_CMD_INT2_REG1 5
#define S35390A_CMD_FREE_REG 7
@@ -36,6 +38,7 @@
#define S35390A_FLAG_POC BIT(0)
#define S35390A_FLAG_BLD BIT(1)
#define S35390A_FLAG_INT2 BIT(2)
+#define S35390A_FLAG_INT1 BIT(3)
#define S35390A_FLAG_24H BIT(6)
#define S35390A_FLAG_RESET BIT(7)
@@ -50,6 +53,14 @@
#define S35390A_INT2_MODE_FREQ BIT(3) /* INT2FE */
#define S35390A_INT2_MODE_PMIN (BIT(3) | BIT(2)) /* INT2FE | INT2ME */
+/* INT1 pin output mode */
+#define S35390A_INT1_MODE_MASK 0xE0
+#define S35390A_INT1_MODE_NOINTR 0x00
+#define S35390A_INT1_MODE_ALARM BIT(5) /* INT1AE */
+#define S35390A_INT1_MODE_PMIN_EDG BIT(6) /* INT1ME */
+#define S35390A_INT1_MODE_FREQ BIT(7) /* INT1FE */
+#define S35390A_INT1_MODE_PMIN (BIT(7) | BIT(6)) /* INT1FE | INT1ME */
+
static const struct i2c_device_id s35390a_id[] = {
{ .name = "s35390a" },
{ }
@@ -65,6 +76,7 @@ MODULE_DEVICE_TABLE(of, s35390a_of_match);
struct s35390a {
struct i2c_client *client[8];
int twentyfourhour;
+ bool wakealarm_use_int1;
};
static int s35390a_set_reg(struct s35390a *s35390a, int reg, u8 *buf, int len)
@@ -275,7 +287,7 @@ static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
struct i2c_client *client = to_i2c_client(dev);
struct s35390a *s35390a = i2c_get_clientdata(client);
u8 buf[3], sts = 0;
- int err, i;
+ int err, i, reg;
dev_dbg(&client->dev, "%s: alm is secs=%d, mins=%d, hours=%d mday=%d, "\
"mon=%d, year=%d, wday=%d\n", __func__, alm->time.tm_sec,
@@ -293,9 +305,13 @@ static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
return err;
if (alm->enabled)
- sts = S35390A_INT2_MODE_ALARM;
+ sts = s35390a->wakealarm_use_int1
+ ? S35390A_INT1_MODE_ALARM
+ : S35390A_INT2_MODE_ALARM;
else
- sts = S35390A_INT2_MODE_NOINTR;
+ sts = s35390a->wakealarm_use_int1
+ ? S35390A_INT1_MODE_NOINTR
+ : S35390A_INT2_MODE_NOINTR;
/* set interrupt mode*/
err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
@@ -317,8 +333,11 @@ static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
for (i = 0; i < 3; ++i)
buf[i] = bitrev8(buf[i]);
- err = s35390a_set_reg(s35390a, S35390A_CMD_INT2_REG1, buf,
- sizeof(buf));
+ reg = s35390a->wakealarm_use_int1
+ ? S35390A_CMD_INT1_REG1
+ : S35390A_CMD_INT2_REG1;
+
+ err = s35390a_set_reg(s35390a, reg, buf, sizeof(buf));
return err;
}
@@ -328,13 +347,21 @@ static int s35390a_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
struct i2c_client *client = to_i2c_client(dev);
struct s35390a *s35390a = i2c_get_clientdata(client);
u8 buf[3], sts;
- int i, err;
+ int i, err, reg, mask, mode;
err = s35390a_get_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
if (err < 0)
return err;
- if ((sts & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
+ mask = s35390a->wakealarm_use_int1
+ ? S35390A_INT1_MODE_MASK
+ : S35390A_INT2_MODE_MASK;
+
+ mode = s35390a->wakealarm_use_int1
+ ? S35390A_INT1_MODE_ALARM
+ : S35390A_INT2_MODE_ALARM;
+
+ if ((sts & mask) != mode) {
/*
* When the alarm isn't enabled, the register to configure
* the alarm time isn't accessible.
@@ -345,7 +372,11 @@ static int s35390a_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
alm->enabled = 1;
}
- err = s35390a_get_reg(s35390a, S35390A_CMD_INT2_REG1, buf, sizeof(buf));
+ reg = s35390a->wakealarm_use_int1
+ ? S35390A_CMD_INT1_REG1
+ : S35390A_CMD_INT2_REG1;
+
+ err = s35390a_get_reg(s35390a, reg, buf, sizeof(buf));
if (err < 0)
return err;
@@ -437,10 +468,10 @@ static int s35390a_nvmem_write(void *priv, unsigned int offset, void *val,
static int s35390a_probe(struct i2c_client *client)
{
int err, err_read;
- unsigned int i;
+ unsigned int i, wakealarm_output_pin = 0;
struct s35390a *s35390a;
struct rtc_device *rtc;
- u8 buf, status1;
+ u8 buf, status1, flag;
struct device *dev = &client->dev;
struct nvmem_config nvmem_cfg = {
.name = "s35390a_nvram",
@@ -452,6 +483,9 @@ static int s35390a_probe(struct i2c_client *client)
.reg_write = s35390a_nvmem_write,
};
+ fwnode_property_read_u32(dev->fwnode, "sii,wakealarm-output-pin",
+ &wakealarm_output_pin);
+
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
return -ENODEV;
@@ -460,6 +494,7 @@ static int s35390a_probe(struct i2c_client *client)
return -ENOMEM;
s35390a->client[0] = client;
+ s35390a->wakealarm_use_int1 = wakealarm_output_pin == S35390A_OUTPUT_PIN_INT1;
i2c_set_clientdata(client, s35390a);
/* This chip uses multiple addresses, use dummy devices for them */
@@ -489,7 +524,9 @@ static int s35390a_probe(struct i2c_client *client)
else
s35390a->twentyfourhour = 0;
- if (status1 & S35390A_FLAG_INT2) {
+ flag = s35390a->wakealarm_use_int1 ? S35390A_FLAG_INT1 : S35390A_FLAG_INT2;
+
+ if (status1 & flag) {
/* disable alarm (and maybe test mode) */
buf = 0;
err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &buf, 1);
@@ -514,7 +551,7 @@ static int s35390a_probe(struct i2c_client *client)
set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->features);
clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features);
- if (status1 & S35390A_FLAG_INT2)
+ if (status1 & flag)
rtc_update_irq(rtc, 1, RTC_AF);
nvmem_cfg.priv = s35390a;
--
2.54.0