rtc, rv3029: add trickle charger support.

Signed-off-by: Heiko Schocher <hs@denx.de> Acked-by: Detlev Zundel <dzu@denx.de>

rtc, rv3029: add trickle charger support.
Signed-off-by: Heiko Schocher <hs@denx.de> Acked-by: Detlev Zundel <dzu@denx.de>
Heiko Schocher · Wolfgang Denk
1 parent 31e413985c
Showing 2 changed files with 89 additions and 0 deletions Side-by-side Diff
README
drivers/rtc/rv3029.c
@@ -748,6 +748,8 @@
 		CONFIG_RTC_ISL1208	- use Intersil ISL1208 RTC
 		CONFIG_RTC_MAX6900	- use Maxim, Inc. MAX6900 RTC
 		CONFIG_SYS_RTC_DS1337_NOOSC	- Turn off the OSC output for DS1337
+		CONFIG_SYS_RV3029_TCR	- enable trickle charger on
+					  RV3029 RTC.
  
 		Note that if the RTC uses I2C, then the I2C interface
 		must also be configured. See I2C Support, below.
@@ -25,6 +25,12 @@
 #include <i2c.h>
 #include <rtc.h>
  
+#define RTC_RV3029_CTRL1	0x00
+#define RTC_RV3029_CTRL1_EERE	(1 << 3)
+
+#define RTC_RV3029_CTRL_STATUS	0x03
+#define RTC_RV3029_CTRLS_EEBUSY	(1 << 7)
+
 #define RTC_RV3029_CTRL_RESET	0x04
 #define RTC_RV3029_CTRL_SYS_R	(1 << 4)
  
@@ -42,6 +48,12 @@
 #define RV3029C2_REG_HR_12_24          (1 << 6)  /* 24h/12h mode */
 #define RV3029C2_REG_HR_PM             (1 << 5)  /* PM/AM bit in 12h mode */
  
+#define RTC_RV3029_EEPROM_CTRL	0x30
+#define RTC_RV3029_TRICKLE_1K	(1 << 4)
+#define RTC_RV3029_TRICKLE_5K	(1 << 5)
+#define RTC_RV3029_TRICKLE_20K	(1 << 6)
+#define RTC_RV3029_TRICKLE_80K	(1 << 7)
+
 int rtc_get( struct rtc_time *tmp )
 {
 	int	ret;
@@ -113,6 +125,41 @@
 	return 0;
 }
  
+/* sets EERE-Bit  (automatic EEPROM refresh) */
+static void set_eere_bit(int state)
+{
+	int ret;
+	unsigned char reg_ctrl1;
+
+	ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
+			&reg_ctrl1, 1);
+
+	if (state)
+		reg_ctrl1 |= RTC_RV3029_CTRL1_EERE;
+	else
+		reg_ctrl1 &= (~RTC_RV3029_CTRL1_EERE);
+
+	ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
+		&reg_ctrl1, 1);
+}
+
+/* waits until EEPROM page is no longer busy (times out after 10ms*loops) */
+static int wait_eebusy(int loops)
+{
+	int i, ret;
+	unsigned char ctrl_status;
+
+	for (i = 0; i < loops; i++) {
+		ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_STATUS,
+			1, &ctrl_status, 1);
+
+		if ((ctrl_status & RTC_RV3029_CTRLS_EEBUSY) == 0)
+			break;
+		udelay(10000);
+	}
+	return i;
+}
+
 void rtc_reset (void)
 {
 	int	ret;
@@ -121,5 +168,45 @@
 	buf[0] = RTC_RV3029_CTRL_SYS_R;
 	ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_RESET, 1,
 			buf, 1);
+
+#if defined(CONFIG_SYS_RV3029_TCR)
+	/*
+	 * because EEPROM_CTRL register is in EEPROM page it is necessary to
+	 * disable automatic EEPROM refresh and check if EEPROM is busy
+	 * before EEPORM_CTRL register may be accessed
+	 */
+	set_eere_bit(0);
+	wait_eebusy(100);
+	/* read current trickle charger setting */
+	ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_EEPROM_CTRL,
+			1, buf, 1);
+	/* enable automatic EEPROM refresh again */
+	set_eere_bit(1);
+
+	/*
+	 * to minimize EEPROM access write trickle charger setting only if it
+	 * differs from current value
+	 */
+	if ((buf[0] & 0xF0) != CONFIG_SYS_RV3029_TCR) {
+		buf[0] = (buf[0] & 0x0F) | CONFIG_SYS_RV3029_TCR;
+		/*
+		 * write trickle charger setting (disable autom. EEPROM
+		 * refresh and wait until EEPROM is idle)
+		 */
+		set_eere_bit(0);
+		wait_eebusy(100);
+		ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR,
+				RTC_RV3029_EEPROM_CTRL, 1, buf, 1);
+		/*
+		 * it is necessary to wait 10ms before EEBUSY-Bit may be read
+		 * (this is not documented in the data sheet yet, but the
+		 * manufacturer recommends it)
+		 */
+		udelay(10000);
+		/* wait until EEPROM write access is finished */
+		wait_eebusy(100);
+		set_eere_bit(1);
+	}
+#endif
 }
...	...	@@ -748,6 +748,8 @@
748	748	CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
749	749	CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
750	750	CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
	751	+ CONFIG_SYS_RV3029_TCR - enable trickle charger on
	752	+ RV3029 RTC.
751	753
752	754	Note that if the RTC uses I2C, then the I2C interface
753	755	must also be configured. See I2C Support, below.
...	...	@@ -25,6 +25,12 @@
25	25	#include <i2c.h>
26	26	#include <rtc.h>
27	27
	28	+#define RTC_RV3029_CTRL1 0x00
	29	+#define RTC_RV3029_CTRL1_EERE (1 << 3)
	30	+
	31	+#define RTC_RV3029_CTRL_STATUS 0x03
	32	+#define RTC_RV3029_CTRLS_EEBUSY (1 << 7)
	33	+
28	34	#define RTC_RV3029_CTRL_RESET 0x04
29	35	#define RTC_RV3029_CTRL_SYS_R (1 << 4)
30	36
...	...	@@ -42,6 +48,12 @@
42	48	#define RV3029C2_REG_HR_12_24 (1 << 6) /* 24h/12h mode */
43	49	#define RV3029C2_REG_HR_PM (1 << 5) /* PM/AM bit in 12h mode */
44	50
	51	+#define RTC_RV3029_EEPROM_CTRL 0x30
	52	+#define RTC_RV3029_TRICKLE_1K (1 << 4)
	53	+#define RTC_RV3029_TRICKLE_5K (1 << 5)
	54	+#define RTC_RV3029_TRICKLE_20K (1 << 6)
	55	+#define RTC_RV3029_TRICKLE_80K (1 << 7)
	56	+
45	57	int rtc_get( struct rtc_time *tmp )
46	58	{
47	59	int ret;
...	...	@@ -113,6 +125,41 @@
113	125	return 0;
114	126	}
115	127
	128	+/* sets EERE-Bit (automatic EEPROM refresh) */
	129	+static void set_eere_bit(int state)
	130	+{
	131	+ int ret;
	132	+ unsigned char reg_ctrl1;
	133	+
	134	+ ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
	135	+ &reg_ctrl1, 1);
	136	+
	137	+ if (state)
	138	+ reg_ctrl1 \|= RTC_RV3029_CTRL1_EERE;
	139	+ else
	140	+ reg_ctrl1 &= (~RTC_RV3029_CTRL1_EERE);
	141	+
	142	+ ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
	143	+ &reg_ctrl1, 1);
	144	+}
	145	+
	146	+/* waits until EEPROM page is no longer busy (times out after 10msloops) /
	147	+static int wait_eebusy(int loops)
	148	+{
	149	+ int i, ret;
	150	+ unsigned char ctrl_status;
	151	+
	152	+ for (i = 0; i < loops; i++) {
	153	+ ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_STATUS,
	154	+ 1, &ctrl_status, 1);
	155	+
	156	+ if ((ctrl_status & RTC_RV3029_CTRLS_EEBUSY) == 0)
	157	+ break;
	158	+ udelay(10000);
	159	+ }
	160	+ return i;
	161	+}
	162	+
116	163	void rtc_reset (void)
117	164	{
118	165	int ret;
...	...	@@ -121,5 +168,45 @@
121	168	buf[0] = RTC_RV3029_CTRL_SYS_R;
122	169	ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_RESET, 1,
123	170	buf, 1);
	171	+
	172	+#if defined(CONFIG_SYS_RV3029_TCR)
	173	+ /*
	174	+ * because EEPROM_CTRL register is in EEPROM page it is necessary to
	175	+ * disable automatic EEPROM refresh and check if EEPROM is busy
	176	+ * before EEPORM_CTRL register may be accessed
	177	+ */
	178	+ set_eere_bit(0);
	179	+ wait_eebusy(100);
	180	+ /* read current trickle charger setting */
	181	+ ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_EEPROM_CTRL,
	182	+ 1, buf, 1);
	183	+ /* enable automatic EEPROM refresh again */
	184	+ set_eere_bit(1);
	185	+
	186	+ /*
	187	+ * to minimize EEPROM access write trickle charger setting only if it
	188	+ * differs from current value
	189	+ */
	190	+ if ((buf[0] & 0xF0) != CONFIG_SYS_RV3029_TCR) {
	191	+ buf[0] = (buf[0] & 0x0F) \| CONFIG_SYS_RV3029_TCR;
	192	+ /*
	193	+ * write trickle charger setting (disable autom. EEPROM
	194	+ * refresh and wait until EEPROM is idle)
	195	+ */
	196	+ set_eere_bit(0);
	197	+ wait_eebusy(100);
	198	+ ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR,
	199	+ RTC_RV3029_EEPROM_CTRL, 1, buf, 1);
	200	+ /*
	201	+ * it is necessary to wait 10ms before EEBUSY-Bit may be read
	202	+ * (this is not documented in the data sheet yet, but the
	203	+ * manufacturer recommends it)
	204	+ */
	205	+ udelay(10000);
	206	+ /* wait until EEPROM write access is finished */
	207	+ wait_eebusy(100);
	208	+ set_eere_bit(1);
	209	+ }
	210	+#endif
124	211	}