From 3e664f6d50ea7f5d6ea96a028fc8f099236e99be Mon Sep 17 00:00:00 2001 From: Balaji T K Date: Thu, 25 Nov 2010 16:22:04 +0530 Subject: ARMV7: OMAP4: twl6030 add battery charging support Add battery charging support twl6030 driver. Add support for battery voltage and current measurements. Add command to get battery status and start/stop battery charging from USB. Signed-off-by: Balaji T K Tested-by: Steve Sakoman Signed-off-by: Sandeep Paulraj --- drivers/power/twl6030.c | 124 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 122 insertions(+), 2 deletions(-) (limited to 'drivers/power') diff --git a/drivers/power/twl6030.c b/drivers/power/twl6030.c index cf1da6b..fef57b4 100644 --- a/drivers/power/twl6030.c +++ b/drivers/power/twl6030.c @@ -36,6 +36,54 @@ static inline int twl6030_i2c_read_u8(u8 chip_no, u8 *val, u8 reg) return i2c_read(chip_no, reg, 1, val, 1); } +static int twl6030_gpadc_read_channel(u8 channel_no) +{ + u8 lsb = 0; + u8 msb = 0; + int ret = 0; + + ret = twl6030_i2c_read_u8(TWL6030_CHIP_ADC, &lsb, + GPCH0_LSB + channel_no * 2); + if (ret) + return ret; + + ret = twl6030_i2c_read_u8(TWL6030_CHIP_ADC, &msb, + GPCH0_MSB + channel_no * 2); + if (ret) + return ret; + + return (msb << 8) | lsb; +} + +static int twl6030_gpadc_sw2_trigger(void) +{ + u8 val; + int ret = 0; + + ret = twl6030_i2c_write_u8(TWL6030_CHIP_ADC, CTRL_P2_SP2, CTRL_P2); + if (ret) + return ret; + + /* Waiting until the SW1 conversion ends*/ + val = CTRL_P2_BUSY; + + while (!((val & CTRL_P2_EOCP2) && (!(val & CTRL_P2_BUSY)))) { + ret = twl6030_i2c_read_u8(TWL6030_CHIP_ADC, &val, CTRL_P2); + if (ret) + return ret; + udelay(1000); + } + + return 0; +} + +void twl6030_stop_usb_charging(void) +{ + twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, 0, CONTROLLER_CTRL1); + + return; +} + void twl6030_start_usb_charging(void) { twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, CHARGERUSB_VICHRG_1500, @@ -48,17 +96,89 @@ void twl6030_start_usb_charging(void) CHARGERUSB_INT_MASK); twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, CHARGERUSB_VOREG_4P0, CHARGERUSB_VOREG); - twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, CHARGERUSB_CTRL2_VITERM_100, + twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, CHARGERUSB_CTRL2_VITERM_400, CHARGERUSB_CTRL2); + twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, TERM, CHARGERUSB_CTRL1); /* Enable USB charging */ twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, CONTROLLER_CTRL1_EN_CHARGER, CONTROLLER_CTRL1); return; } +int twl6030_get_battery_current(void) +{ + int battery_current = 0; + u8 msb = 0; + u8 lsb = 0; + + twl6030_i2c_read_u8(TWL6030_CHIP_CHARGER, &msb, FG_REG_11); + twl6030_i2c_read_u8(TWL6030_CHIP_CHARGER, &lsb, FG_REG_10); + battery_current = ((msb << 8) | lsb); + + /* convert 10 bit signed number to 16 bit signed number */ + if (battery_current >= 0x2000) + battery_current = (battery_current - 0x4000); + + battery_current = battery_current * 3000 / 4096; + printf("Battery Current: %d mA\n", battery_current); + + return battery_current; +} + +int twl6030_get_battery_voltage(void) +{ + int battery_volt = 0; + int ret = 0; + + /* Start GPADC SW conversion */ + ret = twl6030_gpadc_sw2_trigger(); + if (ret) { + printf("Failed to convert battery voltage\n"); + return ret; + } + + /* measure Vbat voltage */ + battery_volt = twl6030_gpadc_read_channel(7); + if (battery_volt < 0) { + printf("Failed to read battery voltage\n"); + return ret; + } + battery_volt = (battery_volt * 25 * 1000) >> (10 + 2); + printf("Battery Voltage: %d mV\n", battery_volt); + + return battery_volt; +} + void twl6030_init_battery_charging(void) { - twl6030_start_usb_charging(); + u8 stat1 = 0; + int battery_volt = 0; + int ret = 0; + + /* Enable VBAT measurement */ + twl6030_i2c_write_u8(TWL6030_CHIP_PM, VBAT_MEAS, MISC1); + + /* Enable GPADC module */ + ret = twl6030_i2c_write_u8(TWL6030_CHIP_CHARGER, FGS | GPADCS, TOGGLE1); + if (ret) { + printf("Failed to enable GPADC\n"); + return; + } + + battery_volt = twl6030_get_battery_voltage(); + if (battery_volt < 0) + return; + + if (battery_volt < 3000) + printf("Main battery voltage too low!\n"); + + /* Check for the presence of USB charger */ + twl6030_i2c_read_u8(TWL6030_CHIP_CHARGER, &stat1, CONTROLLER_STAT1); + + /* check for battery presence indirectly via Fuel gauge */ + if ((stat1 & VBUS_DET) && (battery_volt < 3300)) + twl6030_start_usb_charging(); + return; } -- cgit v1.1