2 files changed, 61 insertions, 0 deletions

diff --git a/drivers/power/twl4030_charger.c b/drivers/power/twl4030_charger.c
index 3e6e99101106..0511610b235f 100644
--- a/drivers/power/twl4030_charger.c
+++ b/drivers/power/twl4030_charger.c
@@ -28,6 +28,7 @@
 #define TWL4030_BCIVBUS         0x0c
 #define TWL4030_BCIMFSTS4       0x10
 #define TWL4030_BCICTL1         0x23
+#define TWL4030_BB_CFG          0x12
 
 #define TWL4030_BCIAUTOWEN      BIT(5)
 #define TWL4030_CONFIG_DONE     BIT(4)
@@ -37,6 +38,17 @@
 #define TWL4030_USBFASTMCHG     BIT(2)
 #define TWL4030_STS_VBUS        BIT(7)
 #define TWL4030_STS_USB_ID      BIT(2)
+#define TWL4030_BBCHEN          BIT(4)
+#define TWL4030_BBSEL_MASK      0b1100
+#define TWL4030_BBSEL_2V5       0b0000
+#define TWL4030_BBSEL_3V0       0b0100
+#define TWL4030_BBSEL_3V1       0b1000
+#define TWL4030_BBSEL_3V2       0b1100
+#define TWL4030_BBISEL_MASK     0b11
+#define TWL4030_BBISEL_25uA     0b00
+#define TWL4030_BBISEL_150uA    0b01
+#define TWL4030_BBISEL_500uA    0b10
+#define TWL4030_BBISEL_1000uA   0b11
 
 /* BCI interrupts */
 #define TWL4030_WOVF            BIT(0) /* Watchdog overflow */
@@ -202,6 +214,49 @@ static int twl4030_charger_enable_ac(bool enable)
 }
 
 /*
+ * Enable/Disable charging of Backup Battery.
+ */
+static int twl4030_charger_enable_backup(int uvolt, int uamp)
+{
+        int ret;
+        u8 flags;
+
+        if (uvolt < 2500000 ||
+            uamp < 25) {
+                /* disable charging of backup battery */
+                ret = twl4030_clear_set(TWL4030_MODULE_PM_RECEIVER,
+                                        TWL4030_BBCHEN, 0, TWL4030_BB_CFG);
+                return ret;
+        }
+
+        flags = TWL4030_BBCHEN;
+        if (uvolt >= 3200000)
+                flags |= TWL4030_BBSEL_3V2;
+        else if (uvolt >= 3100000)
+                flags |= TWL4030_BBSEL_3V1;
+        else if (uvolt >= 3000000)
+                flags |= TWL4030_BBSEL_3V0;
+        else
+                flags |= TWL4030_BBSEL_2V5;
+
+        if (uamp >= 1000)
+                flags |= TWL4030_BBISEL_1000uA;
+        else if (uamp >= 500)
+                flags |= TWL4030_BBISEL_500uA;
+        else if (uamp >= 150)
+                flags |= TWL4030_BBISEL_150uA;
+        else
+                flags |= TWL4030_BBISEL_25uA;
+
+        ret = twl4030_clear_set(TWL4030_MODULE_PM_RECEIVER,
+                                TWL4030_BBSEL_MASK | TWL4030_BBISEL_MASK,
+                                flags,
+                                TWL4030_BB_CFG);
+
+        return ret;
+}
+
+/*
  * TWL4030 CHG_PRES (AC charger presence) events
  */
 static irqreturn_t twl4030_charger_interrupt(int irq, void *arg)
@@ -424,6 +479,7 @@ static enum power_supply_property twl4030_charger_props[] = {
 static int __init twl4030_bci_probe(struct platform_device *pdev)
 {
         struct twl4030_bci *bci;
+        struct twl4030_bci_platform_data *pdata = pdev->dev.platform_data;
         int ret;
         u32 reg;
 
@@ -503,6 +559,8 @@ static int __init twl4030_bci_probe(struct platform_device *pdev)
 
         twl4030_charger_enable_ac(true);
         twl4030_charger_enable_usb(bci, true);
+        twl4030_charger_enable_backup(pdata->bb_uvolt,
+                                      pdata->bb_uamp);
 
         return 0;
 
@@ -531,6 +589,7 @@ static int __exit twl4030_bci_remove(struct platform_device *pdev)
 
         twl4030_charger_enable_ac(false);
         twl4030_charger_enable_usb(bci, false);
+        twl4030_charger_enable_backup(0, 0);
 
         /* mask interrupts */
         twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, 0xff,
diff --git a/include/linux/i2c/twl.h b/include/linux/i2c/twl.h
index 3993477103a5..8eec4403b170 100644
--- a/include/linux/i2c/twl.h
+++ b/include/linux/i2c/twl.h
@@ -555,6 +555,8 @@ struct twl4030_clock_init_data {
 struct twl4030_bci_platform_data {
         int *battery_tmp_tbl;
         unsigned int tblsize;
+        int     bb_uvolt;       /* voltage to charge backup battery */
+        int     bb_uamp;        /* current for backup battery charging */
 };
 
 /* TWL4030_GPIO_MAX (18) GPIOs, with interrupts */