[U-Boot] [PATCH v1 2/2] rtc: Add DM support to ds1307
Chris Packham
judge.packham at gmail.com
Fri Apr 21 16:27:43 UTC 2017
Add an implementation of the ds1307 driver that uses the driver model
i2c APIs.
Signed-off-by: Chris Packham <judge.packham at gmail.com>
---
drivers/rtc/Kconfig | 7 ++
drivers/rtc/ds1307.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++-----
2 files changed, 184 insertions(+), 19 deletions(-)
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index cb79a01..d06130c7 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -23,4 +23,11 @@ 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_DS1307
+ bool "Enable DS1307 driver"
+ depends on DM_RTC
+ help
+ Support for Dallas Semiconductor (now Maxim) DS1307 and DS1338/9 and
+ compatible Real Time Clock devices.
+
endmenu
diff --git a/drivers/rtc/ds1307.c b/drivers/rtc/ds1307.c
index 3be1da6..68d1b65 100644
--- a/drivers/rtc/ds1307.c
+++ b/drivers/rtc/ds1307.c
@@ -16,29 +16,12 @@
#include <common.h>
#include <command.h>
+#include <dm.h>
#include <rtc.h>
#include <i2c.h>
#if defined(CONFIG_CMD_DATE)
-/*---------------------------------------------------------------------*/
-#undef DEBUG_RTC
-
-#ifdef DEBUG_RTC
-#define DEBUGR(fmt,args...) printf(fmt ,##args)
-#else
-#define DEBUGR(fmt,args...)
-#endif
-/*---------------------------------------------------------------------*/
-
-#ifndef CONFIG_SYS_I2C_RTC_ADDR
-# define CONFIG_SYS_I2C_RTC_ADDR 0x68
-#endif
-
-#if defined(CONFIG_RTC_DS1307) && (CONFIG_SYS_I2C_SPEED > 100000)
-# error The DS1307 is specified only up to 100kHz!
-#endif
-
/*
* RTC register addresses
*/
@@ -62,6 +45,26 @@
#define MCP7941X_BIT_ST 0x80
#define MCP7941X_BIT_VBATEN 0x08
+#ifndef CONFIG_DM_RTC
+
+/*---------------------------------------------------------------------*/
+#undef DEBUG_RTC
+
+#ifdef DEBUG_RTC
+#define DEBUGR(fmt, args...) printf(fmt, ##args)
+#else
+#define DEBUGR(fmt, args...)
+#endif
+/*---------------------------------------------------------------------*/
+
+#ifndef CONFIG_SYS_I2C_RTC_ADDR
+# define CONFIG_SYS_I2C_RTC_ADDR 0x68
+#endif
+
+#if defined(CONFIG_RTC_DS1307) && (CONFIG_SYS_I2C_SPEED > 100000)
+# error The DS1307 is specified only up to 100kHz!
+#endif
+
static uchar rtc_read (uchar reg);
static void rtc_write (uchar reg, uchar val);
@@ -211,4 +214,159 @@ static void rtc_write (uchar reg, uchar val)
{
i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
}
-#endif
+
+#else
+static int ds1307_rtc_set(struct udevice *dev, const struct rtc_time *tm)
+{
+ int ret;
+ uchar buf[7];
+
+ debug("Set 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);
+
+ if (tm->tm_year < 1970 || tm->tm_year > 2069)
+ printf("WARNING: year should be between 1970 and 2069!\n");
+
+ buf[RTC_YR_REG_ADDR] = bin2bcd(tm->tm_year % 100);
+ buf[RTC_MON_REG_ADDR] = bin2bcd(tm->tm_mon);
+ buf[RTC_DAY_REG_ADDR] = bin2bcd(tm->tm_wday + 1);
+ buf[RTC_DATE_REG_ADDR] = bin2bcd(tm->tm_mday);
+ buf[RTC_HR_REG_ADDR] = bin2bcd(tm->tm_hour);
+ buf[RTC_MIN_REG_ADDR] = bin2bcd(tm->tm_min);
+ buf[RTC_SEC_REG_ADDR] = bin2bcd(tm->tm_sec);
+
+ if (of_device_is_compatible(dev, "microchip,mcp7941x")) {
+ buf[RTC_DAY_REG_ADDR] |= MCP7941X_BIT_VBATEN;
+ buf[RTC_SEC_REG_ADDR] |= MCP7941X_BIT_ST;
+ }
+
+ ret = dm_i2c_write(dev, 0, buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ds1307_rtc_get(struct udevice *dev, struct rtc_time *tm)
+{
+ int ret;
+ uchar buf[7];
+
+read_rtc:
+ ret = dm_i2c_read(dev, 0, buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ if (of_device_is_compatible(dev, "dallas,ds1307")) {
+ if (buf[RTC_SEC_REG_ADDR] & RTC_SEC_BIT_CH) {
+ printf("### Warning: RTC oscillator has stopped\n");
+ /* clear the CH flag */
+ buf[RTC_SEC_REG_ADDR] &= ~RTC_SEC_BIT_CH;
+ dm_i2c_reg_write(dev, RTC_SEC_REG_ADDR,
+ buf[RTC_SEC_REG_ADDR]);
+ return -1;
+ }
+ }
+
+ if (of_device_is_compatible(dev, "dallas,mcp7941x")) {
+ /* make sure that the backup battery is enabled */
+ if (!(buf[RTC_DAY_REG_ADDR] & MCP7941X_BIT_VBATEN)) {
+ dm_i2c_reg_write(dev, RTC_DAY_REG_ADDR,
+ buf[RTC_DAY_REG_ADDR] |
+ MCP7941X_BIT_VBATEN);
+ }
+
+ /* clock halted? turn it on, so clock can tick. */
+ if (!(buf[RTC_SEC_REG_ADDR] & MCP7941X_BIT_ST)) {
+ dm_i2c_reg_write(dev, RTC_SEC_REG_ADDR,
+ MCP7941X_BIT_ST);
+ printf("Started RTC\n");
+ goto read_rtc;
+ }
+ }
+
+ tm->tm_sec = bcd2bin(buf[RTC_SEC_REG_ADDR] & 0x7F);
+ tm->tm_min = bcd2bin(buf[RTC_MIN_REG_ADDR] & 0x7F);
+ tm->tm_hour = bcd2bin(buf[RTC_HR_REG_ADDR] & 0x3F);
+ tm->tm_mday = bcd2bin(buf[RTC_DATE_REG_ADDR] & 0x3F);
+ tm->tm_mon = bcd2bin(buf[RTC_MON_REG_ADDR] & 0x1F);
+ tm->tm_year = bcd2bin(buf[RTC_YR_REG_ADDR]) +
+ (bcd2bin(buf[RTC_YR_REG_ADDR]) >= 70 ?
+ 1900 : 2000);
+ tm->tm_wday = bcd2bin((buf[RTC_DAY_REG_ADDR] - 1) & 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 0;
+}
+
+static int ds1307_rtc_reset(struct udevice *dev)
+{
+ int ret;
+ struct rtc_time tmp = {
+ .tm_year = 1970,
+ .tm_mon = 1,
+ .tm_mday = 1,
+ .tm_hour = 0,
+ .tm_min = 0,
+ .tm_sec = 0,
+ };
+
+ /* clear Clock Halt */
+ ret = dm_i2c_reg_write(dev, RTC_SEC_REG_ADDR, 0x00);
+ if (ret < 0)
+ return ret;
+ ret = dm_i2c_reg_write(dev, RTC_CTL_REG_ADDR,
+ RTC_CTL_BIT_SQWE | RTC_CTL_BIT_RS1 |
+ RTC_CTL_BIT_RS0);
+ if (ret < 0)
+ return ret;
+
+ ret = ds1307_rtc_set(dev, &tmp);
+ if (ret < 0)
+ return ret;
+
+ debug("RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n",
+ tmp.tm_year, tmp.tm_mon, tmp.tm_mday,
+ tmp.tm_hour, tmp.tm_min, tmp.tm_sec);
+
+ return 0;
+}
+
+static int ds1307_probe(struct udevice *dev)
+{
+ i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS |
+ DM_I2C_CHIP_WR_ADDRESS);
+
+ return 0;
+}
+
+static const struct rtc_ops ds1307_rtc_ops = {
+ .get = ds1307_rtc_get,
+ .set = ds1307_rtc_set,
+ .reset = ds1307_rtc_reset,
+};
+
+static const struct udevice_id ds1307_rtc_ids[] = {
+ { .compatible = "dallas,ds1307" },
+ { .compatible = "dallas,ds1337" },
+ { .compatible = "dallas,ds1340" },
+ { .compatible = "microchip,mcp7941x" },
+ { }
+};
+
+U_BOOT_DRIVER(rtc_ds1307) = {
+ .name = "rtc-ds1307",
+ .id = UCLASS_RTC,
+ .probe = ds1307_probe,
+ .of_match = ds1307_rtc_ids,
+ .ops = &ds1307_rtc_ops,
+};
+#endif /* CONFIG_DM_RTC */
+
+#endif /* CONFIG_CMD_DATE*/
--
2.10.1
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