OMAP3: pandora: enable battery backup capacitor

Pandora has a capacitor connected as backup battery, which allows
retaining RTC for some time while main battery is removed. Enable backup
battery charge function to charge that capacitor.
Signed-off-by: NGrazvydas Ignotas <notasas@gmail.com>
Signed-off-by: NSandeep Paulraj <s-paulraj@ti.com>

board/pandora/pandora.c

@@ -37,6 +37,10 @@
 #include <asm/mach-types.h>
 #include "pandora.h"
 
+#define TWL4030_BB_CFG_BBCHEN		(1 << 4)
+#define TWL4030_BB_CFG_BBSEL_3200MV	(3 << 2)
+#define TWL4030_BB_CFG_BBISEL_500UA	2
+
 /*
  * Routine: board_init
  * Description: Early hardware init.
@@ -78,6 +82,11 @@ int misc_init_r(void)
 	writel(GPIO28, &gpio5_base->setdataout);
 	writel(GPIO4, &gpio6_base->setdataout);
 
+	/* Enable battery backup capacitor (3.2V, 0.5mA charge current) */
+	twl4030_i2c_write_u8(TWL4030_CHIP_PM_RECEIVER,
+		TWL4030_BB_CFG_BBCHEN | TWL4030_BB_CFG_BBSEL_3200MV |
+		TWL4030_BB_CFG_BBISEL_500UA, TWL4030_PM_RECEIVER_BB_CFG);
+
 	dieid_num_r();
 
 	return 0;