power: Add twl4030_madc battery driver.
authorMarek Belisko <marek@goldelico.com>
Thu, 29 Aug 2013 09:41:52 +0000 (11:41 +0200)
committerAnton Vorontsov <anton@enomsg.org>
Sat, 31 Aug 2013 00:34:52 +0000 (17:34 -0700)
This driver is used and tested on gta04 phone. It's using twl4030_madc
(similar to rx51 existing driver). Driver also implement charging and
discharging calibration data so user can define ranges and level.

Signed-off-by: Marek Belisko <marek@goldelico.com>
Signed-off-by: Lukas Märdian <lukas@goldelico.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
drivers/power/Kconfig
drivers/power/Makefile
drivers/power/twl4030_madc_battery.c [new file with mode: 0644]
include/linux/power/twl4030_madc_battery.h [new file with mode: 0644]

index e8970a6..bb49ab6 100644 (file)
@@ -216,6 +216,13 @@ config BATTERY_S3C_ADC
        help
          Say Y here to enable support for iPAQ h1930/h1940/rx1950 battery
 
+config BATTERY_TWL4030_MADC
+       tristate "TWL4030 MADC battery driver"
+       depends on TWL4030_MADC
+       help
+         Say Y here to enable this dumb driver for batteries managed
+         through the TWL4030 MADC.
+
 config CHARGER_88PM860X
        tristate "Marvell 88PM860x Charger driver"
        depends on MFD_88PM860X && BATTERY_88PM860X
index 4ae4533..a4b7417 100644 (file)
@@ -34,6 +34,7 @@ obj-$(CONFIG_BATTERY_MAX17040)        += max17040_battery.o
 obj-$(CONFIG_BATTERY_MAX17042) += max17042_battery.o
 obj-$(CONFIG_BATTERY_Z2)       += z2_battery.o
 obj-$(CONFIG_BATTERY_S3C_ADC)  += s3c_adc_battery.o
+obj-$(CONFIG_BATTERY_TWL4030_MADC)     += twl4030_madc_battery.o
 obj-$(CONFIG_CHARGER_88PM860X) += 88pm860x_charger.o
 obj-$(CONFIG_CHARGER_PCF50633) += pcf50633-charger.o
 obj-$(CONFIG_BATTERY_JZ4740)   += jz4740-battery.o
diff --git a/drivers/power/twl4030_madc_battery.c b/drivers/power/twl4030_madc_battery.c
new file mode 100644 (file)
index 0000000..7ef445a
--- /dev/null
@@ -0,0 +1,245 @@
+/*
+ * Dumb driver for LiIon batteries using TWL4030 madc.
+ *
+ * Copyright 2013 Golden Delicious Computers
+ * Lukas Märdian <lukas@goldelico.com>
+ *
+ * Based on dumb driver for gta01 battery
+ * Copyright 2009 Openmoko, Inc
+ * Balaji Rao <balajirrao@openmoko.org>
+ */
+
+#include <linux/module.h>
+#include <linux/param.h>
+#include <linux/delay.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/slab.h>
+#include <linux/sort.h>
+#include <linux/i2c/twl4030-madc.h>
+#include <linux/power/twl4030_madc_battery.h>
+
+struct twl4030_madc_battery {
+       struct power_supply psy;
+       struct twl4030_madc_bat_platform_data *pdata;
+};
+
+static enum power_supply_property twl4030_madc_bat_props[] = {
+       POWER_SUPPLY_PROP_PRESENT,
+       POWER_SUPPLY_PROP_STATUS,
+       POWER_SUPPLY_PROP_TECHNOLOGY,
+       POWER_SUPPLY_PROP_VOLTAGE_NOW,
+       POWER_SUPPLY_PROP_CURRENT_NOW,
+       POWER_SUPPLY_PROP_CAPACITY,
+       POWER_SUPPLY_PROP_CHARGE_FULL,
+       POWER_SUPPLY_PROP_CHARGE_NOW,
+       POWER_SUPPLY_PROP_TEMP,
+       POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
+};
+
+static int madc_read(int index)
+{
+       struct twl4030_madc_request req;
+       int val;
+
+       req.channels = index;
+       req.method = TWL4030_MADC_SW2;
+       req.type = TWL4030_MADC_WAIT;
+       req.do_avg = 0;
+       req.raw = false;
+       req.func_cb = NULL;
+
+       val = twl4030_madc_conversion(&req);
+       if (val < 0)
+               return val;
+
+       return req.rbuf[ffs(index) - 1];
+}
+
+static int twl4030_madc_bat_get_charging_status(void)
+{
+       return (madc_read(TWL4030_MADC_ICHG) > 0) ? 1 : 0;
+}
+
+static int twl4030_madc_bat_get_voltage(void)
+{
+       return madc_read(TWL4030_MADC_VBAT);
+}
+
+static int twl4030_madc_bat_get_current(void)
+{
+       return madc_read(TWL4030_MADC_ICHG) * 1000;
+}
+
+static int twl4030_madc_bat_get_temp(void)
+{
+       return madc_read(TWL4030_MADC_BTEMP) * 10;
+}
+
+static int twl4030_madc_bat_voltscale(struct twl4030_madc_battery *bat,
+                                       int volt)
+{
+       struct twl4030_madc_bat_calibration *calibration;
+       int i, res = 0;
+
+       /* choose charging curve */
+       if (twl4030_madc_bat_get_charging_status())
+               calibration = bat->pdata->charging;
+       else
+               calibration = bat->pdata->discharging;
+
+       if (volt > calibration[0].voltage) {
+               res = calibration[0].level;
+       } else {
+               for (i = 0; calibration[i+1].voltage >= 0; i++) {
+                       if (volt <= calibration[i].voltage &&
+                                       volt >= calibration[i+1].voltage) {
+                               /* interval found - interpolate within range */
+                               res = calibration[i].level -
+                                       ((calibration[i].voltage - volt) *
+                                       (calibration[i].level -
+                                       calibration[i+1].level)) /
+                                       (calibration[i].voltage -
+                                       calibration[i+1].voltage);
+                               break;
+                       }
+               }
+       }
+       return res;
+}
+
+static int twl4030_madc_bat_get_property(struct power_supply *psy,
+                                       enum power_supply_property psp,
+                                       union power_supply_propval *val)
+{
+       struct twl4030_madc_battery *bat = container_of(psy,
+                                       struct twl4030_madc_battery, psy);
+
+       switch (psp) {
+       case POWER_SUPPLY_PROP_STATUS:
+               if (twl4030_madc_bat_voltscale(bat,
+                               twl4030_madc_bat_get_voltage()) > 95)
+                       val->intval = POWER_SUPPLY_STATUS_FULL;
+               else {
+                       if (twl4030_madc_bat_get_charging_status())
+                               val->intval = POWER_SUPPLY_STATUS_CHARGING;
+                       else
+                               val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+               }
+               break;
+       case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+               val->intval = twl4030_madc_bat_get_voltage() * 1000;
+               break;
+       case POWER_SUPPLY_PROP_TECHNOLOGY:
+               val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+               break;
+       case POWER_SUPPLY_PROP_CURRENT_NOW:
+               val->intval = twl4030_madc_bat_get_current();
+               break;
+       case POWER_SUPPLY_PROP_PRESENT:
+               /* assume battery is always present */
+               val->intval = 1;
+               break;
+       case POWER_SUPPLY_PROP_CHARGE_NOW: {
+                       int percent = twl4030_madc_bat_voltscale(bat,
+                                       twl4030_madc_bat_get_voltage());
+                       val->intval = (percent * bat->pdata->capacity) / 100;
+                       break;
+               }
+       case POWER_SUPPLY_PROP_CAPACITY:
+               val->intval = twl4030_madc_bat_voltscale(bat,
+                                       twl4030_madc_bat_get_voltage());
+               break;
+       case POWER_SUPPLY_PROP_CHARGE_FULL:
+               val->intval = bat->pdata->capacity;
+               break;
+       case POWER_SUPPLY_PROP_TEMP:
+               val->intval = twl4030_madc_bat_get_temp();
+               break;
+       case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: {
+                       int percent = twl4030_madc_bat_voltscale(bat,
+                                       twl4030_madc_bat_get_voltage());
+                       /* in mAh */
+                       int chg = (percent * (bat->pdata->capacity/1000))/100;
+
+                       /* assume discharge with 400 mA (ca. 1.5W) */
+                       val->intval = (3600l * chg) / 400;
+                       break;
+               }
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static void twl4030_madc_bat_ext_changed(struct power_supply *psy)
+{
+       struct twl4030_madc_battery *bat = container_of(psy,
+                                       struct twl4030_madc_battery, psy);
+
+       power_supply_changed(&bat->psy);
+}
+
+static int twl4030_cmp(const void *a, const void *b)
+{
+       return ((struct twl4030_madc_bat_calibration *)b)->voltage -
+               ((struct twl4030_madc_bat_calibration *)a)->voltage;
+}
+
+static int twl4030_madc_battery_probe(struct platform_device *pdev)
+{
+       struct twl4030_madc_battery *twl4030_madc_bat;
+       struct twl4030_madc_bat_platform_data *pdata = pdev->dev.platform_data;
+
+       twl4030_madc_bat = kzalloc(sizeof(*twl4030_madc_bat), GFP_KERNEL);
+       if (!twl4030_madc_bat)
+               return -ENOMEM;
+
+       twl4030_madc_bat->psy.name = "twl4030_battery";
+       twl4030_madc_bat->psy.type = POWER_SUPPLY_TYPE_BATTERY;
+       twl4030_madc_bat->psy.properties = twl4030_madc_bat_props;
+       twl4030_madc_bat->psy.num_properties =
+                                       ARRAY_SIZE(twl4030_madc_bat_props);
+       twl4030_madc_bat->psy.get_property = twl4030_madc_bat_get_property;
+       twl4030_madc_bat->psy.external_power_changed =
+                                       twl4030_madc_bat_ext_changed;
+
+       /* sort charging and discharging calibration data */
+       sort(pdata->charging, pdata->charging_size,
+               sizeof(struct twl4030_madc_bat_calibration),
+               twl4030_cmp, NULL);
+       sort(pdata->discharging, pdata->discharging_size,
+               sizeof(struct twl4030_madc_bat_calibration),
+               twl4030_cmp, NULL);
+
+       twl4030_madc_bat->pdata = pdata;
+       platform_set_drvdata(pdev, twl4030_madc_bat);
+       power_supply_register(&pdev->dev, &twl4030_madc_bat->psy);
+
+       return 0;
+}
+
+static int twl4030_madc_battery_remove(struct platform_device *pdev)
+{
+       struct twl4030_madc_battery *bat = platform_get_drvdata(pdev);
+
+       power_supply_unregister(&bat->psy);
+       kfree(bat);
+
+       return 0;
+}
+
+static struct platform_driver twl4030_madc_battery_driver = {
+       .driver = {
+               .name = "twl4030_madc_battery",
+       },
+       .probe  = twl4030_madc_battery_probe,
+       .remove = twl4030_madc_battery_remove,
+};
+module_platform_driver(twl4030_madc_battery_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Lukas Märdian <lukas@goldelico.com>");
+MODULE_DESCRIPTION("twl4030_madc battery driver");
diff --git a/include/linux/power/twl4030_madc_battery.h b/include/linux/power/twl4030_madc_battery.h
new file mode 100644 (file)
index 0000000..23110dc
--- /dev/null
@@ -0,0 +1,39 @@
+/*
+ * Dumb driver for LiIon batteries using TWL4030 madc.
+ *
+ * Copyright 2013 Golden Delicious Computers
+ * Nikolaus Schaller <hns@goldelico.com>
+ *
+ *  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.
+ *
+ *  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.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#ifndef __TWL4030_MADC_BATTERY_H
+#define __TWL4030_MADC_BATTERY_H
+
+/*
+ * Usually we can assume 100% @ 4.15V and 0% @ 3.3V but curves differ for
+ * charging and discharging!
+ */
+
+struct twl4030_madc_bat_calibration {
+       short voltage;  /* in mV - specify -1 for end of list */
+       short level;    /* in percent (0 .. 100%) */
+};
+
+struct twl4030_madc_bat_platform_data {
+       unsigned int capacity;  /* total capacity in uAh */
+       struct twl4030_madc_bat_calibration *charging;
+       int charging_size;
+       struct twl4030_madc_bat_calibration *discharging;
+       int discharging_size;
+};
+
+#endif