[PATCH v2 1/3] drivers: rtc: add pcf2131 rtc driver
Joy Zou
joy.zou at nxp.com
Fri Jun 2 10:10:33 CEST 2023
Adding support for pcf2131 RTC chip.
The pcf2131 is similar to the pcf2127. The driver support rtc register
read/write by using rtc cmd and rtc date set/get by using date cmd.
Signed-off-by: Joy Zou <joy.zou at nxp.com>
---
Changes in v1:
1. delete the unnecessary initialization in v2.
2. retrun directly function insteand of redundancy return ret in v2.
3. delete the unnecessary comment line.
---
drivers/rtc/Kconfig | 10 +++
drivers/rtc/Makefile | 1 +
drivers/rtc/pcf2131.c | 184 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 195 insertions(+)
create mode 100644 drivers/rtc/pcf2131.c
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 23173139e0..507dc6cbcb 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -64,6 +64,16 @@ config RTC_PCF2127
has a selectable I2C-bus or SPI-bus, a backup battery switch-over circuit, a
programmable watchdog function, a timestamp function, and many other features.
+config RTC_PCF2131
+ bool "Enable PCF2131 driver"
+ depends on DM_RTC
+ help
+ The PCF2131 is a CMOS Real Time Clock (RTC) and calendar with an integrated
+ Temperature Compensated Crystal (Xtal) Oscillator (TCXO) and a 32.768 kHz quartz
+ crystal optimized for very high accuracy and very low power consumption. The PCF2127
+ has a selectable I2C-bus or SPI-bus, a backup battery switch-over circuit, a
+ programmable watchdog function, a timestamp function, and many other features.
+
config RTC_DS1307
bool "Enable DS1307 driver"
depends on DM_RTC
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 308fab8da9..722f2be98f 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_RTC_MV) += mvrtc.o
obj-$(CONFIG_RTC_MXS) += mxsrtc.o
obj-$(CONFIG_RTC_PCF8563) += pcf8563.o
obj-$(CONFIG_RTC_PCF2127) += pcf2127.o
+obj-$(CONFIG_RTC_PCF2131) += pcf2131.o
obj-$(CONFIG_RTC_PL031) += pl031.o
obj-$(CONFIG_RTC_PT7C4338) += pt7c4338.o
obj-$(CONFIG_RTC_RV3028) += rv3028.o
diff --git a/drivers/rtc/pcf2131.c b/drivers/rtc/pcf2131.c
new file mode 100644
index 0000000000..c3f16b07bb
--- /dev/null
+++ b/drivers/rtc/pcf2131.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * The NXP PCF2131 RTC uboot driver.
+ * Copyright 2023 NXP
+ * Date & Time support for PCF2131 RTC
+ */
+
+#include <common.h>
+#include <command.h>
+#include <dm.h>
+#include <i2c.h>
+#include <log.h>
+#include <rtc.h>
+
+#define PCF2131_REG_CTRL1 0x00
+#define PCF2131_BIT_CTRL1_STOP BIT(5)
+#define PCF2131_BIT_CTRL1_100TH_S_DIS BIT(4)
+#define PCF2131_REG_CTRL2 0x01
+#define PCF2131_REG_CTRL3 0x02
+#define PCF2131_REG_SR_RESET 0x05
+#define PCF2131_SR_VAL_Clr_Pres 0xa4
+#define PCF2131_REG_SC 0x07
+#define PCF2131_REG_MN 0x08
+#define PCF2131_REG_HR 0x09
+#define PCF2131_REG_DM 0x0a
+#define PCF2131_REG_DW 0x0b
+#define PCF2131_REG_MO 0x0c
+#define PCF2131_REG_YR 0x0d
+
+static int pcf2131_rtc_read(struct udevice *dev, uint offset, u8 *buffer, uint len)
+{
+ struct dm_i2c_chip *chip = dev_get_parent_plat(dev);
+ struct i2c_msg msg;
+ int ret;
+
+ /* Set the address of the start register to be read */
+ ret = dm_i2c_write(dev, offset, NULL, 0);
+ if (ret < 0)
+ return ret;
+
+ /* Read register's data */
+ msg.addr = chip->chip_addr;
+ msg.flags |= I2C_M_RD;
+ msg.len = len;
+ msg.buf = buffer;
+
+ return dm_i2c_xfer(dev, &msg, 1);
+}
+
+static int pcf2131_rtc_lock(struct udevice *dev)
+{
+ int ret = 0;
+ uchar buf[6] = { PCF2131_REG_CTRL1 };
+
+ ret = pcf2131_rtc_read(dev, PCF2131_REG_CTRL1, buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ buf[PCF2131_REG_CTRL1] |= PCF2131_BIT_CTRL1_STOP;
+ ret = dm_i2c_write(dev, PCF2131_REG_CTRL1, &buf[PCF2131_REG_CTRL1], 1);
+ if (ret < 0)
+ return ret;
+
+ buf[PCF2131_REG_SR_RESET] = PCF2131_SR_VAL_Clr_Pres;
+
+ return dm_i2c_write(dev, PCF2131_REG_SR_RESET, &buf[PCF2131_REG_SR_RESET], 1);
+}
+
+static int pcf2131_rtc_unlock(struct udevice *dev)
+{
+ int ret = 0;
+ uchar buf[6] = { PCF2131_REG_CTRL1 };
+
+ ret = pcf2131_rtc_read(dev, PCF2131_REG_CTRL1, buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ buf[PCF2131_REG_CTRL1] &= ~PCF2131_BIT_CTRL1_STOP;
+ return dm_i2c_write(dev, PCF2131_REG_CTRL1, &buf[PCF2131_REG_CTRL1], 1);
+}
+
+static int pcf2131_rtc_write(struct udevice *dev, uint offset,
+ const u8 *buffer, uint len)
+{
+ int ret = 0;
+
+ ret = pcf2131_rtc_lock(dev);
+ if (ret < 0)
+ return ret;
+
+ ret = dm_i2c_write(dev, offset, buffer, len);
+ if (ret < 0)
+ return ret;
+
+ return pcf2131_rtc_unlock(dev);
+}
+
+static int pcf2131_rtc_set(struct udevice *dev, const struct rtc_time *tm)
+{
+ uchar buf[7];
+ int i = 0, ret;
+
+ /* hours, minutes and seconds */
+ buf[i++] = bin2bcd(tm->tm_sec);
+ buf[i++] = bin2bcd(tm->tm_min);
+ buf[i++] = bin2bcd(tm->tm_hour);
+ buf[i++] = bin2bcd(tm->tm_mday);
+ buf[i++] = tm->tm_wday & 0x07;
+
+ /* month, 1 - 12 */
+ buf[i++] = bin2bcd(tm->tm_mon);
+
+ /* year */
+ buf[i++] = bin2bcd(tm->tm_year % 100);
+
+ ret = pcf2131_rtc_lock(dev);
+ if (ret < 0)
+ return ret;
+
+ /* write register's data */
+ ret = dm_i2c_write(dev, PCF2131_REG_SC, buf, i);
+ if (ret < 0)
+ return ret;
+
+ return pcf2131_rtc_unlock(dev);
+}
+
+static int pcf2131_rtc_get(struct udevice *dev, struct rtc_time *tm)
+{
+ int ret = 0;
+ uchar buf[16];
+
+ ret = pcf2131_rtc_read(dev, PCF2131_REG_CTRL1, buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ if (buf[PCF2131_REG_CTRL3] & 0x04)
+ puts("### Warning: RTC Low Voltage - date/time not reliable\n");
+
+ tm->tm_sec = bcd2bin(buf[PCF2131_REG_SC] & 0x7F);
+ tm->tm_min = bcd2bin(buf[PCF2131_REG_MN] & 0x7F);
+ tm->tm_hour = bcd2bin(buf[PCF2131_REG_HR] & 0x3F);
+ tm->tm_mday = bcd2bin(buf[PCF2131_REG_DM] & 0x3F);
+ tm->tm_mon = bcd2bin(buf[PCF2131_REG_MO] & 0x1F);
+ tm->tm_year = bcd2bin(buf[PCF2131_REG_YR]) + 1900;
+ if (tm->tm_year < 1970)
+ tm->tm_year += 100; /* assume we are in 1970...2069 */
+ tm->tm_wday = buf[PCF2131_REG_DW] & 0x07;
+ tm->tm_yday = 0;
+ tm->tm_isdst = 0;
+
+ debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
+ tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
+ tm->tm_hour, tm->tm_min, tm->tm_sec);
+
+ return ret;
+}
+
+static int pcf2131_rtc_reset(struct udevice *dev)
+{
+ /*Doing nothing here*/
+
+ return 0;
+}
+
+static const struct rtc_ops pcf2131_rtc_ops = {
+ .get = pcf2131_rtc_get,
+ .set = pcf2131_rtc_set,
+ .reset = pcf2131_rtc_reset,
+ .read = pcf2131_rtc_read,
+ .write = pcf2131_rtc_write,
+};
+
+static const struct udevice_id pcf2131_rtc_ids[] = {
+ { .compatible = "nxp,pcf2131" },
+ { }
+};
+
+U_BOOT_DRIVER(rtc_pcf2131) = {
+ .name = "rtc-pcf2131",
+ .id = UCLASS_RTC,
+ .of_match = pcf2131_rtc_ids,
+ .ops = &pcf2131_rtc_ops,
+};
--
2.37.1
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