@@ -23,6 +23,7 @@
#define NCT3018Y_REG_CTRL 0x0A /* timer control */
#define NCT3018Y_REG_ST 0x0B /* status */
#define NCT3018Y_REG_CLKO 0x0C /* clock out */
+#define NCT3018Y_REG_PART 0x21 /* part info */
#define NCT3018Y_BIT_AF BIT(7)
#define NCT3018Y_BIT_ST BIT(7)
@@ -37,10 +38,12 @@
#define NCT3018Y_REG_BAT_MASK 0x07
#define NCT3018Y_REG_CLKO_F_MASK 0x03 /* frequenc mask */
#define NCT3018Y_REG_CLKO_CKE 0x80 /* clock out enabled */
+#define NCT3018Y_REG_PART_NCT3018Y 0x02
struct nct3018y {
struct rtc_device *rtc;
struct i2c_client *client;
+ int part_num;
#ifdef CONFIG_COMMON_CLK
struct clk_hw clkout_hw;
#endif
@@ -177,8 +180,27 @@ static int nct3018y_rtc_read_time(struct device *dev, struct rtc_time *tm)
static int nct3018y_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct i2c_client *client = to_i2c_client(dev);
+ struct nct3018y *nct3018y = dev_get_drvdata(dev);
unsigned char buf[4] = {0};
- int err;
+ int err, flags;
+ int restore_flags = 0;
+
+ flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL);
+ if (flags < 0) {
+ dev_dbg(&client->dev, "Failed to read NCT3018Y_REG_CTRL.\n");
+ return flags;
+ }
+
+ /* Check and set TWO bit */
+ if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y && !(flags & NCT3018Y_BIT_TWO)) {
+ restore_flags = 1;
+ flags |= NCT3018Y_BIT_TWO;
+ err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
+ if (err < 0) {
+ dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n");
+ return err;
+ }
+ }
buf[0] = bin2bcd(tm->tm_sec);
err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_SC, buf[0]);
@@ -212,6 +234,18 @@ static int nct3018y_rtc_set_time(struct device *dev, struct rtc_time *tm)
return -EIO;
}
+ /* Restore TWO bit */
+ if (restore_flags) {
+ if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y)
+ flags &= ~NCT3018Y_BIT_TWO;
+
+ err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
+ if (err < 0) {
+ dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n");
+ return err;
+ }
+ }
+
return err;
}
@@ -479,11 +513,17 @@ static int nct3018y_probe(struct i2c_client *client)
dev_dbg(&client->dev, "%s: NCT3018Y_BIT_TWO is set\n", __func__);
}
- flags = NCT3018Y_BIT_TWO;
- err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
- if (err < 0) {
- dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL\n");
- return err;
+ nct3018y->part_num = i2c_smbus_read_byte_data(client, NCT3018Y_REG_PART);
+ if (nct3018y->part_num < 0) {
+ dev_dbg(&client->dev, "Failed to read NCT3018Y_REG_PART.\n");
+ return nct3018y->part_num;
+ } else if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y) {
+ flags = NCT3018Y_BIT_HF;
+ err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
+ if (err < 0) {
+ dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n");
+ return err;
+ }
}
flags = 0;
The NCT3015Y-R and NCT3018Y-R use the same datasheet but have different topologies as follows. - Topology (Only 1st i2c can set TWO bit and HF bit) In NCT3015Y-R, rtc 1st i2c is connected to a host CPU rtc 2nd i2c is connected to a BMC In NCT3018Y-R, rtc 1st i2c is connected to a BMC rtc 2nd i2c is connected to a host CPU In order to be compatible with NCT3015Y-R and NCT3018Y-R, - In probe, If part number is NCT3018Y-R, only set HF bit to 24-Hour format. Else, do nothing - In set_time, If part number is NCT3018Y-R && TWO bit is 0, change TWO bit to 1, and restore TWO bit after updating time. Signed-off-by: Mia Lin <mimi05633@gmail.com> --- Changes since version 7: Fix the part number parameter checking issue. drivers/rtc/rtc-nct3018y.c | 52 +++++++++++++++++++++++++++++++++----- 1 file changed, 46 insertions(+), 6 deletions(-)