From 14688f1a91e1f37bc6bf50ff5241e857f24338e0 Mon Sep 17 00:00:00 2001 From: Mia Lin Date: Mon, 13 Nov 2023 18:38:07 +0800 Subject: rtc: nuvoton: Compatible with NCT3015Y-R and NCT3018Y-R 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 Link: https://lore.kernel.org/r/20231113103807.1036978-2-mimi05633@gmail.com Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-nct3018y.c | 52 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 46 insertions(+), 6 deletions(-) diff --git a/drivers/rtc/rtc-nct3018y.c b/drivers/rtc/rtc-nct3018y.c index ed4e606be8e5..f488a189a465 100644 --- a/drivers/rtc/rtc-nct3018y.c +++ b/drivers/rtc/rtc-nct3018y.c @@ -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; -- cgit