[PATCH] Add National LP8727 charger driver

From: Woogyom Kim
Date: Thu Sep 01 2011 - 04:05:42 EST


LP8727 is the battery charger with Micro/Mini USB interface.
This IC includes below functions
- I2c interface for accessing user registers
- Single input Li-Ion battery charger
- Charger input ID detection from Micro/Mini USB
- multiplexing switches on USB, UART
---
drivers/power/Kconfig | 6 +
drivers/power/Makefile | 1 +
drivers/power/lp8727_charger.c | 478 ++++++++++++++++++++++++++++++++++++++++
include/linux/lp8727.h | 54 +++++
4 files changed, 539 insertions(+), 0 deletions(-)
create mode 100644 drivers/power/lp8727_charger.c
create mode 100644 include/linux/lp8727.h

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 57de051..51cb302 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -249,4 +249,10 @@ config CHARGER_MAX8998
Say Y to enable support for the battery charger control sysfs and
platform data of MAX8998/LP3974 PMICs.

+config CHARGER_LP8727
+ tristate "National Semiconductor LP8727 charger driver"
+ depends on I2C
+ help
+ Say Y here to enable support for LP8727 Charger Driver.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index b4af13d..aed6098 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -38,3 +38,4 @@ obj-$(CONFIG_CHARGER_TWL4030) += twl4030_charger.o
obj-$(CONFIG_CHARGER_GPIO) += gpio-charger.o
obj-$(CONFIG_CHARGER_MAX8997) += max8997_charger.o
obj-$(CONFIG_CHARGER_MAX8998) += max8998_charger.o
+obj-$(CONFIG_CHARGER_LP8727) += lp8727_charger.o
diff --git a/drivers/power/lp8727_charger.c b/drivers/power/lp8727_charger.c
new file mode 100644
index 0000000..a4b504c
--- /dev/null
+++ b/drivers/power/lp8727_charger.c
@@ -0,0 +1,478 @@
+/*
+ * Driver for LP8727 Micro/Mini USB IC with intergrated charger
+ *
+ * Copyright (C) 2011 National Semiconductor
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/power_supply.h>
+#include <linux/lp8727.h>
+
+#define DEBOUNCE_MSEC 270
+
+/* Registers */
+#define CTRL1 0x1
+#define CTRL2 0x2
+#define SWCTRL 0x3
+#define INT1 0x4
+#define INT2 0x5
+#define STATUS1 0x6
+#define STATUS2 0x7
+#define CHGCTRL2 0x9
+
+/* CTRL1 register */
+#define CP_EN (1 << 0)
+#define ADC_EN (1 << 1)
+#define ID200_EN (1 << 4)
+
+/* CTRL2 register */
+#define CHGDET_EN (1 << 1)
+#define INT_EN (1 << 6)
+
+/* SWCTRL register */
+#define SW_DM1_DM (0x0 << 0)
+#define SW_DM1_U1 (0x1 << 0)
+#define SW_DM1_HiZ (0x7 << 0)
+#define SW_DP2_DP (0x0 << 3)
+#define SW_DP2_U2 (0x1 << 3)
+#define SW_DP2_HiZ (0x7 << 3)
+
+/* INT1 register */
+#define IDNO (0xF << 0)
+#define VBUS (1 << 4)
+
+/* STATUS1 register */
+#define CHGSTAT (3 << 4)
+#define CHPORT (1 << 6)
+#define DCPORT (1 << 7)
+
+/* STATUS2 register */
+#define TEMP_STAT (3 << 5)
+
+enum lp8727_dev_id {
+ ID_NONE,
+ ID_TA,
+ ID_DEDICATED_CHG,
+ ID_USB_CHG,
+ ID_USB_DS,
+ ID_MAX,
+};
+
+enum lp8727_chg_stat {
+ PRECHG,
+ CC,
+ CV,
+ EOC,
+};
+
+struct lp8727_psy {
+ struct power_supply ac;
+ struct power_supply usb;
+ struct power_supply batt;
+};
+
+struct lp8727_chg {
+ struct device *dev;
+ struct i2c_client *client;
+ struct mutex xfer_lock;
+ struct delayed_work work;
+ struct workqueue_struct *irqthread;
+ struct lp8727_platform_data *pdata;
+ struct lp8727_psy *psy;
+ struct lp8727_chg_param *chg_parm;
+ enum lp8727_dev_id devid;
+};
+
+static int lp8727_i2c_read(struct lp8727_chg *pchg, u8 reg, u8 *data, u8 len)
+{
+ s32 ret;
+
+ mutex_lock(&pchg->xfer_lock);
+ ret = i2c_smbus_read_i2c_block_data(pchg->client, reg, len, data);
+ mutex_unlock(&pchg->xfer_lock);
+
+ return (ret != len) ? -EIO : 0;
+}
+
+static int lp8727_i2c_write(struct lp8727_chg *pchg, u8 reg, u8 *data, u8 len)
+{
+ s32 ret;
+
+ mutex_lock(&pchg->xfer_lock);
+ ret = i2c_smbus_write_i2c_block_data(pchg->client, reg, len, data);
+ mutex_unlock(&pchg->xfer_lock);
+
+ return ret;
+}
+
+static int lp8727_is_charger_attached(const char *name, int id)
+{
+ if(name) {
+ if(!strcmp(name, "ac"))
+ return (id == ID_TA || id == ID_DEDICATED_CHG) ? 1 : 0;
+ else if(!strcmp(name, "usb"))
+ return (id == ID_USB_CHG) ? 1 : 0;
+ }
+
+ return (id >= ID_TA && id <= ID_USB_CHG) ? 1 : 0;
+}
+
+static void lp8727_init_device(struct lp8727_chg *pchg)
+{
+ u8 val;
+
+ val = ID200_EN | ADC_EN | CP_EN;
+ if(lp8727_i2c_write(pchg, CTRL1, &val, 1))
+ dev_err(pchg->dev, "i2c write err : addr=0x%.2x\n", CTRL1);
+
+ val = INT_EN | CHGDET_EN;
+ if(lp8727_i2c_write(pchg, CTRL2, &val, 1))
+ dev_err(pchg->dev, "i2c write err : addr=0x%.2x\n", CTRL2);
+}
+
+static int lp8727_is_dedicated_charger(struct lp8727_chg *pchg)
+{
+ u8 val;
+ (void)lp8727_i2c_read(pchg, STATUS1, &val, 1);
+ return (val & DCPORT);
+}
+
+static int lp8727_is_usb_charger(struct lp8727_chg *pchg)
+{
+ u8 val;
+ (void)lp8727_i2c_read(pchg, STATUS1, &val, 1);
+ return (val & CHPORT);
+}
+
+static void lp8727_ctrl_switch(struct lp8727_chg *pchg, u8 sw)
+{
+ u8 val = sw;
+ (void)lp8727_i2c_write(pchg, SWCTRL, &val, 1);
+}
+
+static void lp8727_id_detection(struct lp8727_chg *pchg, u8 id, int vbusin)
+{
+ u8 devid = ID_NONE;
+ u8 swctrl = SW_DM1_HiZ | SW_DP2_HiZ;
+
+ switch(id) {
+ case 0x5:
+ devid = ID_TA;
+ pchg->chg_parm = &pchg->pdata->ac;
+ break;
+ case 0xB:
+ if(lp8727_is_dedicated_charger(pchg)) {
+ pchg->chg_parm = &pchg->pdata->ac;
+ devid = ID_DEDICATED_CHG;
+ } else if(lp8727_is_usb_charger(pchg)) {
+ pchg->chg_parm = &pchg->pdata->usb;
+ devid = ID_USB_CHG;
+ swctrl = SW_DM1_DM | SW_DP2_DP;
+ } else if(vbusin) {
+ devid = ID_USB_DS;
+ swctrl = SW_DM1_DM | SW_DP2_DP;
+ }
+ break;
+ default:
+ devid = ID_NONE;
+ pchg->chg_parm = NULL;
+ break;
+ }
+
+ pchg->devid = devid;
+ lp8727_ctrl_switch(pchg, swctrl);
+}
+
+static void lp8727_enable_chgdet(struct lp8727_chg *pchg)
+{
+ u8 val;
+
+ (void)lp8727_i2c_read(pchg, CTRL2, &val, 1);
+ val |= CHGDET_EN;
+ (void)lp8727_i2c_write(pchg, CTRL2, &val, 1);
+}
+
+static void lp8727_delayed_func(struct work_struct *_work)
+{
+ u8 intstat[2];
+ u8 idno;
+ u8 vbus;
+ struct lp8727_chg *pchg =
+ container_of(_work, struct lp8727_chg, work.work);
+
+ lp8727_i2c_read(pchg, INT1, intstat, 2);
+
+ idno = intstat[0] & IDNO;
+ vbus = intstat[0] & VBUS;
+
+ lp8727_id_detection(pchg, idno, vbus);
+ lp8727_enable_chgdet(pchg);
+
+ power_supply_changed(&pchg->psy->ac);
+ power_supply_changed(&pchg->psy->usb);
+ power_supply_changed(&pchg->psy->batt);
+}
+
+static irqreturn_t lp8727_isr_func(int irq, void *ptr)
+{
+ struct lp8727_chg *pchg = ptr;
+ unsigned long delay = msecs_to_jiffies(DEBOUNCE_MSEC);
+
+ queue_delayed_work(pchg->irqthread, &pchg->work, delay);
+
+ return IRQ_HANDLED;
+}
+
+static void lp8727_intr_config(struct lp8727_chg *pchg)
+{
+ INIT_DELAYED_WORK(&pchg->work, lp8727_delayed_func);
+ pchg->irqthread = create_singlethread_workqueue("lp8727-irqthd");
+
+ if(!pchg->irqthread)
+ dev_err(pchg->dev, "can not create thread for lp8727\n");
+
+ if(request_threaded_irq(pchg->client->irq,
+ NULL,
+ lp8727_isr_func,
+ IRQF_TRIGGER_FALLING,
+ "lp8727_irq",
+ pchg)) {
+ dev_err(pchg->dev, "lp8727 irq can not be registered\n");
+ }
+}
+
+static enum power_supply_property lp8727_charger_prop[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+};
+
+static enum power_supply_property lp8727_battery_prop[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_HEALTH,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_TEMP,
+};
+
+static char *battery_supplied_to[] = {
+ "main_batt",
+};
+
+static int lp8727_charger_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct lp8727_chg *pchg = dev_get_drvdata(psy->dev->parent);
+
+ if(psp == POWER_SUPPLY_PROP_ONLINE) {
+ val->intval = lp8727_is_charger_attached(psy->name,
+ pchg->devid);
+ }
+
+ return 0;
+}
+
+static int lp8727_battery_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct lp8727_chg *pchg = dev_get_drvdata(psy->dev->parent);
+ u8 read;
+
+ switch(psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ if(lp8727_is_charger_attached(psy->name, pchg->devid)) {
+ (void)lp8727_i2c_read(pchg, STATUS1, &read, 1);
+ if(((read & CHGSTAT) >> 4) == EOC)
+ val->intval = POWER_SUPPLY_STATUS_FULL;
+ else
+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
+ } else {
+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+ }
+ break;
+ case POWER_SUPPLY_PROP_HEALTH:
+ (void)lp8727_i2c_read(pchg, STATUS2, &read, 1);
+ read = (read & TEMP_STAT) >> 5;
+ if(read >= 0x1 && read <= 0x3)
+ val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
+ else
+ val->intval = POWER_SUPPLY_HEALTH_GOOD;
+ break;
+ case POWER_SUPPLY_PROP_PRESENT:
+ if(pchg->pdata->get_batt_present)
+ val->intval = pchg->pdata->get_batt_present();
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ if(pchg->pdata->get_batt_level)
+ val->intval = pchg->pdata->get_batt_level();
+ break;
+ case POWER_SUPPLY_PROP_CAPACITY:
+ if(pchg->pdata->get_batt_capacity)
+ val->intval = pchg->pdata->get_batt_capacity();
+ break;
+ case POWER_SUPPLY_PROP_TEMP:
+ if(pchg->pdata->get_batt_temp)
+ val->intval = pchg->pdata->get_batt_temp();
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static void lp8727_charger_changed(struct power_supply *psy)
+{
+ struct lp8727_chg *pchg = dev_get_drvdata(psy->dev->parent);
+ u8 val;
+ u8 eoc_level, ichg;
+
+ if(lp8727_is_charger_attached(psy->name, pchg->devid)) {
+ if(pchg->chg_parm) {
+ eoc_level = pchg->chg_parm->eoc_level;
+ ichg = pchg->chg_parm->ichg;
+ val = (ichg << 4) | eoc_level;
+ (void)lp8727_i2c_write(pchg, CHGCTRL2, &val, 1);
+ }
+ }
+}
+
+static int lp8727_register_psy(struct lp8727_chg *pchg)
+{
+ struct lp8727_psy *psy;
+
+ psy = kzalloc(sizeof(*psy), GFP_KERNEL);
+ if(!psy)
+ goto err_mem;
+
+ pchg->psy = psy;
+
+ psy->ac.name = "ac";
+ psy->ac.type = POWER_SUPPLY_TYPE_MAINS;
+ psy->ac.properties = lp8727_charger_prop;
+ psy->ac.num_properties = ARRAY_SIZE(lp8727_charger_prop);
+ psy->ac.get_property = lp8727_charger_get_property;
+ psy->ac.supplied_to = battery_supplied_to;
+ psy->ac.num_supplicants = ARRAY_SIZE(battery_supplied_to);
+
+ if(power_supply_register(pchg->dev, &psy->ac))
+ goto err_psy;
+
+ psy->usb.name = "usb";
+ psy->usb.type = POWER_SUPPLY_TYPE_USB;
+ psy->usb.properties = lp8727_charger_prop;
+ psy->usb.num_properties = ARRAY_SIZE(lp8727_charger_prop);
+ psy->usb.get_property = lp8727_charger_get_property;
+ psy->usb.supplied_to = battery_supplied_to;
+ psy->usb.num_supplicants = ARRAY_SIZE(battery_supplied_to);
+
+ if(power_supply_register(pchg->dev, &psy->usb))
+ goto err_psy;
+
+ psy->batt.name = "main_batt";
+ psy->batt.type = POWER_SUPPLY_TYPE_BATTERY;
+ psy->batt.properties = lp8727_battery_prop;
+ psy->batt.num_properties = ARRAY_SIZE(lp8727_battery_prop);
+ psy->batt.get_property = lp8727_battery_get_property;
+ psy->batt.external_power_changed = lp8727_charger_changed;
+
+ if(power_supply_register(pchg->dev, &psy->batt))
+ goto err_psy;
+
+ return 0;
+
+err_mem:
+ return -ENOMEM;
+err_psy:
+ kfree(psy);
+ return -EPERM;
+}
+
+static void lp8727_unregister_psy(struct lp8727_chg *pchg)
+{
+ struct lp8727_psy *psy = pchg->psy;
+
+ if(psy) {
+ power_supply_unregister(&psy->ac);
+ power_supply_unregister(&psy->usb);
+ power_supply_unregister(&psy->batt);
+ kfree(psy);
+ }
+}
+
+static int lp8727_probe(struct i2c_client *cl, const struct i2c_device_id *id)
+{
+ struct lp8727_chg *pchg;
+ int ret;
+
+ pchg = kzalloc(sizeof(*pchg), GFP_KERNEL);
+ if(!pchg)
+ return -ENOMEM;
+
+ pchg->client = cl;
+ pchg->dev = &cl->dev;
+ pchg->pdata = cl->dev.platform_data;
+ i2c_set_clientdata(cl, pchg);
+ mutex_init(&pchg->xfer_lock);
+
+ lp8727_init_device(pchg);
+ lp8727_intr_config(pchg);
+
+ ret = lp8727_register_psy(pchg);
+ if(ret) {
+ dev_err(pchg->dev,
+ "can not register power supplies. err=%d", ret);
+ }
+
+ return 0;
+}
+
+static int __devexit lp8727_remove(struct i2c_client *cl)
+{
+ struct lp8727_chg *pchg = i2c_get_clientdata(cl);
+
+ lp8727_unregister_psy(pchg);
+ free_irq(pchg->client->irq, pchg);
+ flush_workqueue(pchg->irqthread);
+ destroy_workqueue(pchg->irqthread);
+ kfree(pchg);
+ return 0;
+}
+
+static const struct i2c_device_id lp8727_ids[] = {
+ {"lp8727", 0},
+};
+
+static struct i2c_driver lp8727_driver = {
+ .driver = {
+ .name = "lp8727",
+ },
+ .probe = lp8727_probe,
+ .remove = __devexit_p(lp8727_remove),
+ .id_table = lp8727_ids,
+};
+
+static int __init lp8727_init(void)
+{
+ return i2c_add_driver(&lp8727_driver);
+}
+module_init(lp8727_init);
+
+static void __exit lp8727_chg_exit(void)
+{
+ i2c_del_driver(&lp8727_driver);
+}
+module_exit(lp8727_chg_exit);
+
+MODULE_DESCRIPTION("National Semiconductor LP8727 charger driver");
+MODULE_AUTHOR("Woogyom Kim <milo.kim@xxxxxxx>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/lp8727.h b/include/linux/lp8727.h
new file mode 100644
index 0000000..b779d0d
--- /dev/null
+++ b/include/linux/lp8727.h
@@ -0,0 +1,54 @@
+/*
+ * lp8727.h - Driver for LP8727 Micro/Mini USB IC with intergrated charger
+ *
+ * Copyright (C) 2011 National Semiconductor
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#ifndef _LP8727_H
+#define _LP8727_H
+
+enum lp8727_eoc_level {
+ EOC_5P,
+ EOC_10P,
+ EOC_16P,
+ EOC_20P,
+ EOC_25P,
+ EOC_33P,
+ EOC_50P,
+};
+
+enum lp8727_ichg {
+ ICHG_90mA,
+ ICHG_100mA,
+ ICHG_400mA,
+ ICHG_450mA,
+ ICHG_500mA,
+ ICHG_600mA,
+ ICHG_700mA,
+ ICHG_800mA,
+ ICHG_900mA,
+ ICHG_1000mA,
+};
+
+struct lp8727_chg_param {
+ /* end of charge level setting */
+ enum lp8727_eoc_level eoc_level;
+ /* charging current */
+ enum lp8727_ichg ichg;
+};
+
+struct lp8727_platform_data {
+ u8 (*get_batt_present)(void);
+ u16 (*get_batt_level)(void);
+ u8 (*get_batt_capacity)(void);
+ u8 (*get_batt_temp)(void);
+ struct lp8727_chg_param ac;
+ struct lp8727_chg_param usb;
+};
+
+#endif
--
1.7.1

Thank you for your help.

Best Regards
Woogyom Kim
milo.kim@xxxxxxx


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