Add GPL-2.0+ SPDX-License-Identifier to source files

[karo-tx-uboot.git] / drivers / rtc / rv3029.c

diff --git a/drivers/rtc/rv3029.c b/drivers/rtc/rv3029.c
index 3ebc76887465db606f458ebabc65ae16f3da1239..f08040a8599a201b2b9c7727d23415be3b9bbfc1 100644 (file)
--- a/drivers/rtc/rv3029.c
+++ b/drivers/rtc/rv3029.c
@@ -2,29 +2,19 @@
  * (C) Copyright 2010
  * Heiko Schocher, DENX Software Engineering, hs@denx.de
  *
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
+ * SPDX-License-Identifier:    GPL-2.0+
  */
 #include <common.h>
 #include <command.h>
 #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 +32,12 @@
 #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;
@@ -72,12 +68,10 @@ int rtc_get( struct rtc_time *tmp )
        tmp->tm_yday = 0;
        tmp->tm_isdst = 0;
 
-#ifdef RTC_DEBUG
-       printf( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
+       debug( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
                tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
                tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
 
-#endif
        return 0;
 }
 
@@ -85,11 +79,10 @@ int rtc_set( struct rtc_time *tmp )
 {
        int     ret;
        unsigned char buf[RTC_RV3029_PAGE_LEN];
-#ifdef RTC_DEBUG
-       printf( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
+
+       debug( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
                tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
                tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
-#endif
 
        if (tmp->tm_year < 2000) {
                printf("RTC: year %d < 2000 not possible\n", tmp->tm_year);
@@ -110,15 +103,88 @@ int rtc_set( struct rtc_time *tmp )
 
        /* give the RTC some time to update */
        udelay(1000);
-       return 0;
+       return ret;
+}
+
+/* sets EERE-Bit  (automatic EEPROM refresh) */
+static void set_eere_bit(int state)
+{
+       unsigned char reg_ctrl1;
+
+       (void)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);
+
+       (void)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;
+       unsigned char ctrl_status;
+
+       for (i = 0; i < loops; i++) {
+               (void)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;
        unsigned char buf[RTC_RV3029_PAGE_LEN];
 
        buf[0] = RTC_RV3029_CTRL_SYS_R;
-       ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_RESET, 1,
+       (void)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 */
+       (void)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);
+               (void)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
 }