Re: [PATCH 2/2] power: Add support for TI BQ24261 charger

From: Andy Shevchenko
Date: Fri Oct 30 2015 - 05:17:58 EST

On Thu, Oct 29, 2015 at 6:34 PM, Ramakrishna Pallala
<ramakrishna.pallala@xxxxxxxxx> wrote:
> Add new charger driver support for TI BQ24261 charger IC.
>
> TI BQ24261 charger driver relies on extcon notifications to get the
> charger cable type and based on that it will set the charging parameters.


> +/*
> + * bq24261_charger.c - BQ24261 Charger driver
> + *
> + * Copyright (C) 2014 Intel Corporation
> + * Author: Jenny TC <jenny.tc@xxxxxxxxx>

Authors:

> + * Ramakrishna Pallala <ramakrishna.pallala@xxxxxxxxx>
> + *

> +#include <linux/version.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>

> +#include <linux/moduleparam.h>

Isn't this one is included in previous?

> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/slab.h>
> +#include <linux/device.h>
> +#include <linux/i2c.h>
> +#include <linux/power_supply.h>
> +#include <linux/extcon.h>
> +#include <linux/io.h>
> +#include <linux/sched.h>
> +#include <linux/delay.h>
> +#include <linux/acpi.h>
> +#include <linux/power/bq24261_charger.h>
> +
> +#define DEV_NAME "bq24261-charger"
> +
> +#define EXCEPTION_MONITOR_DELAY (60 * HZ)
> +#define WDT_RESET_DELAY (15 * HZ)
> +
> +/* BQ24261 registers */
> +#define BQ24261_STAT_CTRL0_ADDR 0x00
> +#define BQ24261_CTRL_ADDR 0x01
> +#define BQ24261_BATT_VOL_CTRL_ADDR 0x02
> +#define BQ24261_VENDOR_REV_ADDR 0x03
> +#define BQ24261_TERM_FCC_ADDR 0x04
> +#define BQ24261_VINDPM_STAT_ADDR 0x05
> +#define BQ24261_ST_NTC_MON_ADDR 0x06
> +
> +#define BQ24261_RESET_ENABLE BIT(7)
> +

Might be a good idea to put comment line preceded each group to refer
which register it covers.

> +#define BQ24261_FAULT_MASK GENMASK(2, 0)

Either use GENMASK in each case, or put plain number.

> +#define BQ24261_VOVP 0x01
> +#define BQ24261_LOW_SUPPLY 0x02
> +#define BQ24261_THERMAL_SHUTDOWN 0x03
> +#define BQ24261_BATT_TEMP_FAULT 0x04
> +#define BQ24261_TIMER_FAULT 0x05
> +#define BQ24261_BATT_OVP 0x06
> +#define BQ24261_NO_BATTERY 0x07
> +#define BQ24261_STAT_MASK (0x03 << 4)
> +#define BQ24261_STAT_READY 0x00

Would be (0x00 << 4) better to explicitly show how you apply this?

> +#define BQ24261_STAT_CHRG_PRGRSS (0x01 << 4)
> +#define BQ24261_STAT_CHRG_DONE (0x02 << 4)
> +#define BQ24261_STAT_FAULT (0x03 << 4)
> +#define BQ24261_BOOST_MASK BIT(6)
> +#define BQ24261_ENABLE_BOOST BIT(6)

Similar, don't mix styles BIT vs. plain numbers. Here (0x01 << 6) looks better.

Why do you need separate _MASK for one bit fields like this?

> +#define BQ24261_TMR_RST_MASK (0x01 << 7)

Ditto.

> +#define BQ24261_TMR_RST (0x01 << 7)
> +
> +#define BQ24261_CE_MASK BIT(1)

Ditto

> +#define BQ24261_CE_DISABLE BIT(1)
> +
> +#define BQ24261_HiZ_MASK BIT(0)

Ditto

> +#define BQ24261_HiZ_ENABLE BIT(0)
> +
> +#define BQ24261_ICHRG_MASK GENMASK(7, 3)
> +
> +#define BQ24261_ITERM_MASK GENMASK(2, 0)
> +#define BQ24261_MIN_ITERM 50 /* 50 mA */
> +#define BQ24261_MAX_ITERM 300 /* 300 mA */
> +
> +#define BQ24261_VBREG_MASK GENMASK(7, 2)
> +#define BQ24261_VBREG_MIN_CV 3500
> +#define BQ24261_VBREG_MAX_CV 4440
> +#define BQ24261_VBREG_CV_DIV 20
> +#define BQ24261_VBREG_CV_BIT_POS 2
> +
> +#define BQ24261_INLMT_MASK GENMASK(6, 4)
> +#define BQ24261_INLMT_100 0x00
> +#define BQ24261_INLMT_150 (0x01 << 4)
> +#define BQ24261_INLMT_500 (0x02 << 4)
> +#define BQ24261_INLMT_900 (0x03 << 4)
> +#define BQ24261_INLMT_1500 (0x04 << 4)
> +#define BQ24261_INLMT_2000 (0x05 << 4)
> +#define BQ24261_INLMT_2500 (0x06 << 4)
> +
> +#define BQ24261_TE_MASK BIT(2)
> +#define BQ24261_TE_ENABLE BIT(2)
> +#define BQ24261_STAT_ENABLE_MASK BIT(3)
> +#define BQ24261_STAT_ENABLE BIT(3)
> +
> +#define BQ24261_VENDOR_MASK GENMASK(7, 5)
> +#define BQ24261_PART_MASK GENMASK(4, 3)
> +#define BQ24261_REV_MASK (0x07)
> +#define VENDOR_BQ2426X (0x02 << 5)
> +#define REV_BQ24261 (0x06)
> +
> +#define BQ24261_TS_MASK BIT(3)
> +#define BQ24261_TS_ENABLED BIT(3)
> +#define BQ24261_BOOST_ILIM_MASK BIT(4)
> +#define BQ24261_BOOST_ILIM_500ma (0x0)
> +#define BQ24261_BOOST_ILIM_1A BIT(4)
> +#define BQ24261_VINDPM_OFF_MASK BIT(0)
> +#define BQ24261_VINDPM_OFF_5V (0x0)
> +#define BQ24261_VINDPM_OFF_12V BIT(0)
> +
> +#define BQ24261_SAFETY_TIMER_MASK GENMASK(6, 5)
> +#define BQ24261_SAFETY_TIMER_40MIN 0x00
> +#define BQ24261_SAFETY_TIMER_6HR (0x01 << 5)
> +#define BQ24261_SAFETY_TIMER_9HR (0x02 << 5)
> +#define BQ24261_SAFETY_TIMER_DISABLED (0x03 << 5)
> +
> +/* Settings for Voltage / DPPM Register (05) */
> +#define BQ24261_VBATT_LEVEL1 3700000
> +#define BQ24261_VBATT_LEVEL2 3960000
> +#define BQ24261_VINDPM_MASK GENMASK(2, 0)
> +#define BQ24261_VINDPM_320MV (0x01 << 2)
> +#define BQ24261_VINDPM_160MV (0x01 << 1)
> +#define BQ24261_VINDPM_80MV (0x01 << 0)
> +#define BQ24261_CD_STATUS_MASK (0x01 << 3)
> +#define BQ24261_DPM_EN_MASK (0x01 << 4)
> +#define BQ24261_DPM_EN_FORCE (0x01 << 4)
> +#define BQ24261_LOW_CHG_MASK (0x01 << 5)
> +#define BQ24261_LOW_CHG_EN (0x01 << 5)
> +#define BQ24261_LOW_CHG_DIS (~BQ24261_LOW_CHG_EN)
> +#define BQ24261_DPM_STAT_MASK (0x01 << 6)
> +#define BQ24261_MINSYS_STAT_MASK (0x01 << 7)
> +
> +#define BQ24261_MIN_CC 500 /* 500mA */
> +#define BQ24261_MAX_CC 3000 /* 3A */
> +#define BQ24261_DEF_CC 1300 /* 1300mA */
> +#define BQ24261_MAX_CV 4350 /*4350mV */
> +#define BQ24261_DEF_CV 4350 /* 4350mV */
> +#define BQ24261_DEF_ITERM 128 /* 128mA */
> +#define BQ24261_MIN_TEMP 0 /* 0 degC */
> +#define BQ24261_MAX_TEMP 60 /* 60 DegC */
> +
> +#define ILIM_100MA 100 /* 100mA */
> +#define ILIM_500MA 500 /* 500mA */
> +#define ILIM_900MA 900 /* 900mA */
> +#define ILIM_1500MA 1500 /* 1500mA */
> +#define ILIM_2000MA 2000 /* 2000mA */
> +#define ILIM_2500MA 2500 /* 2500mA */
> +#define ILIM_3000MA 3000 /* 3000mA */
> +
> +static unsigned int dis_sysfs_write;
> +module_param(dis_sysfs_write, int, 0644);
> +MODULE_PARM_DESC(dis_sysfs_write,
> + "Disable sysfs write on charge current and voltage");
> +
> +u16 bq24261_inlmt[][2] = {
> + {100, BQ24261_INLMT_100},
> + {150, BQ24261_INLMT_150},
> + {500, BQ24261_INLMT_500},
> + {900, BQ24261_INLMT_900},
> + {1500, BQ24261_INLMT_1500},
> + {2000, BQ24261_INLMT_2000},
> + {2500, BQ24261_INLMT_2500},
> +};
> +
> +
> +enum bq24261_status {
> + BQ24261_CHRGR_STAT_UNKNOWN,
> + BQ24261_CHRGR_STAT_READY,
> + BQ24261_CHRGR_STAT_CHARGING,
> + BQ24261_CHRGR_STAT_FULL,
> + BQ24261_CHRGR_STAT_FAULT,
> +};
> +
> +enum bq2426x_model {
> + BQ2426X = 0,
> + BQ24260,
> + BQ24261,
> +};
> +
> +struct bq24261_charger {
> + struct i2c_client *client;
> + struct bq24261_platform_data *pdata;
> + struct power_supply *psy_usb;
> + struct delayed_work fault_mon_work;
> + struct mutex lock;
> + enum bq2426x_model model;
> + struct delayed_work wdt_work;
> + struct work_struct irq_work;
> + struct list_head irq_queue;
> +
> + /* extcon charger cables */
> + struct {
> + struct work_struct work;
> + struct notifier_block nb;
> + struct extcon_specific_cable_nb sdp;
> + struct extcon_specific_cable_nb cdp;
> + struct extcon_specific_cable_nb dcp;
> + struct extcon_specific_cable_nb otg;
> + enum power_supply_type chg_type;
> + bool boost;
> + bool connected;
> + } cable;
> +
> + bool online;
> + bool present;
> + int chg_health;
> + enum bq24261_status chg_status;
> + int cc;
> + int cv;
> + int inlmt;
> + int max_cc;
> + int max_cv;
> + int iterm;
> + int max_temp;
> + int min_temp;
> + bool is_charging_enabled;
> +};
> +
> +static inline int bq24261_read_reg(struct i2c_client *client, u8 reg)
> +{
> + int ret;
> +
> + ret = i2c_smbus_read_byte_data(client, reg);
> + if (ret < 0)
> + dev_err(&client->dev,
> + "error(%d) in reading reg %d\n", ret, reg);
> + return ret;
> +}
> +
> +static inline int bq24261_write_reg(struct i2c_client *client, u8 reg, u8 data)
> +{
> + int ret;
> +
> + ret = i2c_smbus_write_byte_data(client, reg, data);
> + if (ret < 0)
> + dev_err(&client->dev,
> + "error(%d) in writing %d to reg %d\n", ret, data, reg);
> + return ret;
> +}
> +
> +static inline int bq24261_update_reg(struct i2c_client *client, u8 reg,
> + u8 mask, u8 val)
> +{
> + int ret;
> +
> + ret = bq24261_read_reg(client, reg);
> + if (ret < 0)
> + return ret;
> +
> + ret = (ret & ~mask) | (mask & val);
> + return bq24261_write_reg(client, reg, ret);
> +}
> +
> +static void lookup_regval(u16 tbl[][2], size_t size, u16 in_val, u8 *out_val)
> +{
> + int i;
> +
> + for (i = 1; i < size; ++i) {
> + if (in_val < tbl[i][0])
> + break;
> + }
> +
> + *out_val = (u8) tbl[i - 1][1];

No space after casting. Have you run checkpatch.pl?

> +}
> +
> +void bq24261_cc_to_reg(int cc, u8 *reg_val)
> +{
> + /*
> + * Ichrg bits are B3-B7
> + * Icharge = 500mA + IchrgCode * 100mA
> + */
> + cc = clamp_t(int, cc, BQ24261_MIN_CC, BQ24261_MAX_CC);

> + cc = cc - BQ24261_MIN_CC;

Why not do this in previous line? I mean change range to 0.. MAX-MIN.

> + *reg_val = (cc / 100) << 3;


> +}
> +
> +void bq24261_cv_to_reg(int cv, u8 *reg_val)
> +{
> + int val;
> +
> + val = clamp_t(int, cv, BQ24261_VBREG_MIN_CV, BQ24261_VBREG_MAX_CV);
> + *reg_val = (((val - BQ24261_VBREG_MIN_CV) / BQ24261_VBREG_CV_DIV)

Ditto.

> + << BQ24261_VBREG_CV_BIT_POS);
> +}
> +
> +void bq24261_inlmt_to_reg(int inlmt, u8 *regval)
> +{
> + return lookup_regval(bq24261_inlmt, ARRAY_SIZE(bq24261_inlmt),
> + inlmt, regval);
> +}
> +
> +static inline void bq24261_iterm_to_reg(int iterm, u8 *regval)
> +{
> + /*
> + * Iterm bits are B0-B2
> + * Icharge = 50mA + ItermCode * 50mA
> + */
> + iterm = clamp_t(int, iterm, BQ24261_MIN_ITERM, BQ24261_MAX_ITERM);
> + iterm = iterm - BQ24261_MIN_ITERM;

Ditto.

> + *regval = iterm / 50;
> +}
> +
> +static inline int bq24261_init_timers(struct bq24261_charger *chip)
> +{
> + u8 reg_val;
> + int ret;
> +
> + reg_val = BQ24261_SAFETY_TIMER_9HR;
> +
> + if (chip->pdata->thermal_sensing)
> + reg_val |= BQ24261_TS_ENABLED;
> +
> + ret = bq24261_update_reg(chip->client, BQ24261_ST_NTC_MON_ADDR,
> + BQ24261_TS_MASK | BQ24261_SAFETY_TIMER_MASK |
> + BQ24261_BOOST_ILIM_MASK, reg_val);
> +
> + return ret;
> +}
> +
> +static inline int bq24261_reset_wdt_timer(struct bq24261_charger *chip)
> +{
> + u8 mask = BQ24261_TMR_RST_MASK, val = BQ24261_TMR_RST;
> +
> + if (chip->cable.boost) {
> + mask |= BQ24261_BOOST_MASK;
> + val |= BQ24261_ENABLE_BOOST;
> + }
> +
> + return bq24261_update_reg(chip->client, BQ24261_STAT_CTRL0_ADDR,
> + mask, val);
> +}
> +
> +static inline int bq24261_set_cc(struct bq24261_charger *chip, int cc_mA)
> +{
> + u8 reg_val;
> + int ret;
> +
> + dev_dbg(&chip->client->dev, "%s=%d\n", __func__, cc_mA);

> +
> + if (cc_mA && (cc_mA < BQ24261_MIN_CC)) {
> + dev_dbg(&chip->client->dev, "Set LOW_CHG bit\n");
> + reg_val = BQ24261_LOW_CHG_EN;
> + ret = bq24261_update_reg(chip->client,
> + BQ24261_VINDPM_STAT_ADDR,
> + BQ24261_LOW_CHG_MASK, reg_val);
> + return ret;
> + }
> +
> + reg_val = BQ24261_LOW_CHG_DIS;
> + ret = bq24261_update_reg(chip->client, BQ24261_VINDPM_STAT_ADDR,
> + BQ24261_LOW_CHG_MASK, reg_val);
> +
> + bq24261_cc_to_reg(cc_mA, &reg_val);
> +
> + return bq24261_update_reg(chip->client, BQ24261_TERM_FCC_ADDR,
> + BQ24261_ICHRG_MASK, reg_val);
> +}
> +
> +static inline int bq24261_set_cv(struct bq24261_charger *chip, int cv_mV)
> +{
> + u8 reg_val;
> +
> + dev_dbg(&chip->client->dev, "%s=%d\n", __func__, cv_mV);
> +
> + bq24261_cv_to_reg(cv_mV, &reg_val);
> +
> + return bq24261_update_reg(chip->client, BQ24261_BATT_VOL_CTRL_ADDR,
> + BQ24261_VBREG_MASK, reg_val);
> +}
> +
> +static inline int bq24261_set_inlmt(struct bq24261_charger *chip, int inlmt)
> +{
> + u8 reg_val;
> +
> + dev_dbg(&chip->client->dev, "%s=%d\n", __func__, inlmt);
> +
> + bq24261_inlmt_to_reg(inlmt, &reg_val);
> +
> + /*
> + * Don't enable reset bit. Setting this
> + * bit will reset all the registers
> + */
> + reg_val &= ~BQ24261_RESET_ENABLE;
> +
> + return bq24261_update_reg(chip->client, BQ24261_CTRL_ADDR,
> + BQ24261_RESET_ENABLE | BQ24261_INLMT_MASK, reg_val);
> +
> +}
> +
> +static inline int bq24261_set_iterm(struct bq24261_charger *chip, int iterm)
> +{
> + u8 reg_val;
> +
> + bq24261_iterm_to_reg(iterm, &reg_val);
> +
> + return bq24261_update_reg(chip->client, BQ24261_TERM_FCC_ADDR,
> + BQ24261_ITERM_MASK, reg_val);
> +}
> +
> +static inline int bq24261_enable_charging(struct bq24261_charger *chip,
> + bool enable)
> +{
> + int ret;
> + u8 reg_val;
> +
> + if (enable) {
> + reg_val = (~BQ24261_CE_DISABLE & BQ24261_CE_MASK);
> + reg_val |= BQ24261_TE_ENABLE;
> + } else {
> + reg_val = BQ24261_CE_DISABLE;
> + }
> +
> + reg_val |= BQ24261_STAT_ENABLE;
> +
> + /*
> + * Don't enable reset bit. Setting this
> + * bit will reset all the registers
> + */
> + reg_val &= ~BQ24261_RESET_ENABLE;
> +
> + ret = bq24261_update_reg(chip->client, BQ24261_CTRL_ADDR,
> + BQ24261_STAT_ENABLE_MASK | BQ24261_RESET_ENABLE |
> + BQ24261_CE_MASK | BQ24261_TE_MASK,
> + reg_val);
> + if (ret || !enable)
> + return ret;
> +
> + /* Set termination current */
> + ret = bq24261_set_iterm(chip, chip->iterm);
> + if (ret < 0)
> + dev_err(&chip->client->dev, "failed to set iTerm(%d)\n", ret);
> +
> + /* Start WDT and Safety timers */
> + ret = bq24261_init_timers(chip);
> + if (ret)
> + dev_err(&chip->client->dev, "failed to set timers(%d)\n", ret);
> +
> + return ret;
> +}
> +
> +static inline int bq24261_enable_charger(struct bq24261_charger *chip,
> + int enable)
> +{
> + u8 reg_val;
> + int ret;
> +
> + reg_val = enable ? (~BQ24261_HiZ_ENABLE & BQ24261_HiZ_MASK) :
> + BQ24261_HiZ_ENABLE;
> +
> + /*
> + * Don't enable reset bit. Setting this
> + * bit will reset all the registers/
> + */
> + reg_val &= ~BQ24261_RESET_ENABLE;
> +
> + ret = bq24261_update_reg(chip->client, BQ24261_CTRL_ADDR,
> + BQ24261_HiZ_MASK | BQ24261_RESET_ENABLE, reg_val);
> + if (ret)
> + return ret;
> +
> + return bq24261_reset_wdt_timer(chip);
> +}
> +
> +static void bq24261_handle_health(struct bq24261_charger *chip, u8 stat_reg)
> +{
> + struct i2c_client *client = chip->client;
> + bool fault_worker = false;
> +
> + switch (stat_reg & BQ24261_FAULT_MASK) {
> + case BQ24261_VOVP:
> + chip->chg_health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
> + fault_worker = true;
> + dev_err(&client->dev, "Charger Over Voltage Fault\n");
> + break;
> + case BQ24261_LOW_SUPPLY:
> + chip->chg_health = POWER_SUPPLY_HEALTH_DEAD;
> + fault_worker = true;
> + dev_err(&client->dev, "Charger Low Supply Fault\n");
> + break;
> + case BQ24261_THERMAL_SHUTDOWN:
> + chip->chg_health = POWER_SUPPLY_HEALTH_OVERHEAT;
> + dev_err(&client->dev, "Charger Thermal Fault\n");
> + break;
> + case BQ24261_BATT_TEMP_FAULT:
> + dev_err(&client->dev, "Battery Temperature Fault\n");
> + break;
> + case BQ24261_TIMER_FAULT:
> + chip->chg_health = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
> + dev_err(&client->dev, "Charger Timer Fault\n");
> + break;
> + case BQ24261_BATT_OVP:
> + chip->chg_health = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
> + dev_err(&client->dev, "Battery Over Voltage Fault\n");
> + break;
> + case BQ24261_NO_BATTERY:
> + dev_err(&client->dev, "No Battery Connected\n");
> + break;
> + default:
> + chip->chg_health = POWER_SUPPLY_HEALTH_GOOD;
> + }
> +
> + if (fault_worker)
> + schedule_delayed_work(&chip->fault_mon_work,
> + EXCEPTION_MONITOR_DELAY);
> +}
> +
> +static void bq24261_handle_status(struct bq24261_charger *chip, u8 stat_reg)
> +{
> + struct i2c_client *client = chip->client;
> +
> + switch (stat_reg & BQ24261_STAT_MASK) {
> + case BQ24261_STAT_READY:
> + chip->chg_status = BQ24261_CHRGR_STAT_READY;
> + dev_info(&client->dev, "Charger Status: Ready\n");

dev_info? Isn't user be bothered by them?

> + break;
> + case BQ24261_STAT_CHRG_PRGRSS:
> + chip->chg_status = BQ24261_CHRGR_STAT_CHARGING;
> + dev_info(&client->dev, "Charger Status: Charge Progress\n");
> + break;
> + case BQ24261_STAT_CHRG_DONE:
> + chip->chg_status = BQ24261_CHRGR_STAT_FULL;
> + dev_info(&client->dev, "Charger Status: Charge Done\n");
> + break;
> + case BQ24261_STAT_FAULT:
> + chip->chg_status = BQ24261_CHRGR_STAT_FAULT;
> + dev_warn(&client->dev, "Charger Status: Fault\n");
> + break;
> + default:
> + dev_info(&client->dev, "Invalid\n");
> + }
> +}
> +
> +static int bq24261_get_charger_health(struct bq24261_charger *chip)
> +{
> + if (!chip->present)
> + return POWER_SUPPLY_HEALTH_UNKNOWN;
> +
> + return chip->chg_health;
> +}
> +
> +static int bq24261_get_charging_status(struct bq24261_charger *chip)
> +{
> + int status;
> +
> + if (!chip->present)
> + return POWER_SUPPLY_STATUS_DISCHARGING;
> +
> + switch (chip->chg_status) {
> + case BQ24261_CHRGR_STAT_READY:
> + status = POWER_SUPPLY_STATUS_DISCHARGING;
> + break;
> + case BQ24261_CHRGR_STAT_CHARGING:
> + status = POWER_SUPPLY_STATUS_CHARGING;
> + break;
> + case BQ24261_CHRGR_STAT_FULL:
> + status = POWER_SUPPLY_STATUS_FULL;
> + break;
> + case BQ24261_CHRGR_STAT_FAULT:
> + status = POWER_SUPPLY_STATUS_NOT_CHARGING;
> + break;
> + default:
> + status = POWER_SUPPLY_STATUS_DISCHARGING;
> + }
> +
> + return status;
> +}
> +
> +static int bq24261_usb_get_property(struct power_supply *psy,
> + enum power_supply_property psp, union power_supply_propval *val)
> +{
> + struct bq24261_charger *chip = power_supply_get_drvdata(psy);
> +
> + mutex_lock(&chip->lock);
> + switch (psp) {
> + case POWER_SUPPLY_PROP_PRESENT:
> + val->intval = chip->present;
> + break;
> + case POWER_SUPPLY_PROP_ONLINE:
> + val->intval = chip->online;
> + break;
> + case POWER_SUPPLY_PROP_HEALTH:
> + val->intval = bq24261_get_charger_health(chip);
> + break;
> + case POWER_SUPPLY_PROP_STATUS:
> + val->intval = bq24261_get_charging_status(chip);
> + break;
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
> + val->intval = chip->pdata->max_cc * 1000;
> + break;
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
> + val->intval = chip->pdata->max_cv * 1000;
> + break;
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
> + val->intval = chip->cc * 1000;
> + break;
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
> + val->intval = chip->cv * 1000;
> + break;
> + case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
> + val->intval = chip->inlmt * 1000;
> + break;
> + case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT:
> + val->intval = chip->iterm * 1000;
> + break;
> + case POWER_SUPPLY_PROP_TEMP_MAX:
> + val->intval = chip->pdata->max_temp * 10;
> + break;
> + case POWER_SUPPLY_PROP_TEMP_MIN:
> + val->intval = chip->pdata->min_temp * 10;
> + break;
> + default:
> + mutex_unlock(&chip->lock);
> + return -EINVAL;
> + }
> + mutex_unlock(&chip->lock);
> +
> + return 0;
> +}
> +
> +static int bq24261_usb_set_property(struct power_supply *psy,
> + enum power_supply_property psp, const union power_supply_propval *val)
> +{
> + struct bq24261_charger *chip = power_supply_get_drvdata(psy);
> + int intval, ret = 0;

I don't see why we need the assignment.

> +
> + mutex_lock(&chip->lock);

Andy you are protecting exactly what here?

> + switch (psp) {
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
> + /* convert uA to mA */
> + intval = val->intval / 1000;
> + if (intval > chip->max_cc) {
> + ret = -EINVAL;
> + break;
> + }
> +
> + ret = bq24261_set_cc(chip, intval);
> + if (!ret)
> + chip->cc = intval;
> + break;
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
> + /* convert uA to mV */
> + intval = val->intval / 1000;
> + if (intval > chip->max_cv) {
> + ret = -EINVAL;
> + break;
> + }
> +
> + ret = bq24261_set_cv(chip, intval);
> + if (!ret)
> + chip->cv = intval;
> + break;
> + default:
> + ret = -EINVAL;
> + }
> + mutex_unlock(&chip->lock);
> +
> + return ret;
> +}
> +
> +static int bq24261_property_is_writeable(struct power_supply *psy,
> + enum power_supply_property psp)
> +{
> + int ret;

Redundant variable.

> +
> + switch (psp) {
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
> + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
> + ret = 1;
> + break;
> + default:
> + ret = 0;
> + }
> +
> + return ret;
> +}
> +
> +static enum power_supply_property bq24261_usb_props[] = {
> + POWER_SUPPLY_PROP_PRESENT,
> + POWER_SUPPLY_PROP_ONLINE,
> + POWER_SUPPLY_PROP_TYPE,
> + POWER_SUPPLY_PROP_HEALTH,
> + POWER_SUPPLY_PROP_STATUS,
> + POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
> + POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
> + POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
> + POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
> + POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
> + POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT,
> + POWER_SUPPLY_PROP_TEMP_MAX,
> + POWER_SUPPLY_PROP_TEMP_MIN,
> +};
> +
> +static char *bq24261_charger_supplied_to[] = {
> + "main-battery",
> +};
> +
> +static struct power_supply_desc bq24261_charger_desc = {
> + .name = DEV_NAME,
> + .type = POWER_SUPPLY_TYPE_USB,
> + .properties = bq24261_usb_props,
> + .num_properties = ARRAY_SIZE(bq24261_usb_props),
> + .get_property = bq24261_usb_get_property,
> +};
> +
> +static void bq24261_wdt_reset_worker(struct work_struct *work)
> +{
> +
> + struct bq24261_charger *chip = container_of(work,
> + struct bq24261_charger, wdt_work.work);
> + int ret;
> +
> + ret = bq24261_reset_wdt_timer(chip);
> + if (ret)
> + dev_err(&chip->client->dev, "WDT timer reset error(%d)\n", ret);
> +
> + schedule_delayed_work(&chip->wdt_work, WDT_RESET_DELAY);
> +}
> +
> +static void bq24261_irq_worker(struct work_struct *work)
> +{
> + struct bq24261_charger *chip =
> + container_of(work, struct bq24261_charger, irq_work);
> + int ret;
> +
> + /*
> + * Lock to ensure that interrupt register readings are done
> + * and processed sequentially. The interrupt Fault registers
> + * are read on clear and without sequential processing double
> + * fault interrupts or fault recovery cannot be handlled propely
> + */
> +
> + mutex_lock(&chip->lock);
> +
> + ret = bq24261_read_reg(chip->client, BQ24261_STAT_CTRL0_ADDR);
> + if (ret < 0) {
> + dev_err(&chip->client->dev,
> + "Error (%d) in reading BQ24261_STAT_CTRL0_ADDR\n", ret);
> + goto irq_out;
> + }
> +
> + if (!chip->cable.boost) {
> + bq24261_handle_status(chip, ret);
> + bq24261_handle_health(chip, ret);
> + power_supply_changed(chip->psy_usb);
> + }
> +
> +irq_out:
> + mutex_unlock(&chip->lock);
> +}
> +
> +static irqreturn_t bq24261_thread_handler(int id, void *data)
> +{
> + struct bq24261_charger *chip = (struct bq24261_charger *)data;
> +
> + queue_work(system_highpri_wq, &chip->irq_work);
> + return IRQ_HANDLED;
> +}
> +
> +static void bq24261_fault_mon_work(struct work_struct *work)
> +{
> + struct bq24261_charger *chip = container_of(work,
> + struct bq24261_charger, fault_mon_work.work);
> + int ret;
> +
> + if ((chip->chg_health == POWER_SUPPLY_HEALTH_OVERVOLTAGE) ||
> + (chip->chg_health == POWER_SUPPLY_HEALTH_DEAD)) {
> +
> + mutex_lock(&chip->lock);
> + ret = bq24261_read_reg(chip->client, BQ24261_STAT_CTRL0_ADDR);
> + if (ret < 0) {
> + dev_err(&chip->client->dev,
> + "Status register read failed(%d)\n", ret);
> + goto fault_mon_out;
> + }
> +
> + if ((ret & BQ24261_STAT_MASK) == BQ24261_STAT_READY) {
> + dev_info(&chip->client->dev,
> + "Charger fault recovered\n");
> + bq24261_handle_status(chip, ret);
> + bq24261_handle_health(chip, ret);
> + power_supply_changed(chip->psy_usb);
> + }
> +fault_mon_out:
> + mutex_unlock(&chip->lock);
> + }
> +}
> +
> +static void bq24261_boost_control(struct bq24261_charger *chip, bool enable)
> +{
> + int ret;
> +
> + if (enable)
> + ret = bq24261_write_reg(chip->client, BQ24261_STAT_CTRL0_ADDR,
> + BQ24261_TMR_RST | BQ24261_ENABLE_BOOST);
> + else
> + ret = bq24261_write_reg(chip->client,
> + BQ24261_STAT_CTRL0_ADDR, 0x0);
> +
> + if (ret < 0)
> + dev_err(&chip->client->dev,
> + "stat cntl0 reg access error(%d)\n", ret);
> +}
> +
> +static void bq24261_extcon_event_work(struct work_struct *work)
> +{
> + struct bq24261_charger *chip =
> + container_of(work, struct bq24261_charger, cable.work);
> + int ret, current_limit = 0;
> + bool old_connected = chip->cable.connected;
> +
> + /* Determine cable/charger type */
> + if (extcon_get_cable_state(chip->cable.sdp.edev,
> + "SLOW-CHARGER") > 0) {
> + chip->cable.connected = true;
> + current_limit = ILIM_500MA;
> + chip->cable.chg_type = POWER_SUPPLY_TYPE_USB;
> + dev_dbg(&chip->client->dev, "USB SDP charger is connected");
> + } else if (extcon_get_cable_state(chip->cable.cdp.edev,
> + "CHARGE-DOWNSTREAM") > 0) {
> + chip->cable.connected = true;
> + current_limit = ILIM_1500MA;
> + chip->cable.chg_type = POWER_SUPPLY_TYPE_USB_CDP;
> + dev_dbg(&chip->client->dev, "USB CDP charger is connected");
> + } else if (extcon_get_cable_state(chip->cable.dcp.edev,
> + "FAST-CHARGER") > 0) {
> + chip->cable.connected = true;
> + current_limit = ILIM_1500MA;
> + chip->cable.chg_type = POWER_SUPPLY_TYPE_USB_DCP;
> + dev_dbg(&chip->client->dev, "USB DCP charger is connected");
> + } else if (extcon_get_cable_state(chip->cable.otg.edev,
> + "USB-Host") > 0) {
> + chip->cable.boost = true;
> + chip->cable.connected = true;
> + dev_dbg(&chip->client->dev, "USB-Host cable is connected");
> + } else {
> + if (old_connected)
> + dev_dbg(&chip->client->dev, "USB Cable disconnected");
> + chip->cable.connected = false;
> + chip->cable.boost = false;
> + chip->cable.chg_type = POWER_SUPPLY_TYPE_USB;
> + }
> +
> + /* Cable status changed */
> + if (old_connected == chip->cable.connected)
> + return;
> +
> + mutex_lock(&chip->lock);
> + if (chip->cable.connected && !chip->cable.boost) {
> + chip->inlmt = current_limit;
> + /* Set up charging */
> + ret = bq24261_set_cc(chip, chip->cc);
> + if (ret < 0)
> + dev_err(&chip->client->dev, "set CC failed(%d)", ret);
> + ret = bq24261_set_cv(chip, chip->cv);
> + if (ret < 0)
> + dev_err(&chip->client->dev, "set CV failed(%d)", ret);
> + ret = bq24261_set_inlmt(chip, chip->inlmt);
> + if (ret < 0)
> + dev_err(&chip->client->dev, "set ILIM failed(%d)", ret);
> + ret = bq24261_enable_charger(chip, true);
> + if (ret < 0)
> + dev_err(&chip->client->dev,
> + "enable charger failed(%d)", ret);
> + ret = bq24261_enable_charging(chip, true);
> + if (ret < 0)
> + dev_err(&chip->client->dev,
> + "enable charging failed(%d)", ret);
> +
> + chip->is_charging_enabled = true;
> + chip->present = true;
> + chip->online = true;
> + schedule_delayed_work(&chip->wdt_work, 0);
> + } else if (chip->cable.connected && chip->cable.boost) {
> + /* Enable VBUS for Host Mode */
> + bq24261_boost_control(chip, true);
> + schedule_delayed_work(&chip->wdt_work, 0);
> + } else {
> + dev_info(&chip->client->dev, "Cable disconnect event\n");
> + cancel_delayed_work_sync(&chip->wdt_work);
> + cancel_delayed_work_sync(&chip->fault_mon_work);
> + bq24261_boost_control(chip, false);
> + ret = bq24261_enable_charging(chip, false);
> + if (ret < 0)
> + dev_err(&chip->client->dev,
> + "charger disable failed(%d)", ret);
> +
> + chip->is_charging_enabled = false;
> + chip->present = false;
> + chip->online = false;
> + chip->inlmt = 0;
> + }
> + bq24261_charger_desc.type = chip->cable.chg_type;
> + mutex_unlock(&chip->lock);
> + power_supply_changed(chip->psy_usb);
> +}
> +
> +static int bq24261_handle_extcon_events(struct notifier_block *nb,
> + unsigned long event, void *param)
> +{
> + struct bq24261_charger *chip =
> + container_of(nb, struct bq24261_charger, cable.nb);
> +
> + dev_dbg(&chip->client->dev, "external connector event(%ld)\n", event);
> +
> + schedule_work(&chip->cable.work);
> + return NOTIFY_OK;
> +}
> +
> +static int bq24261_extcon_register(struct bq24261_charger *chip)
> +{
> + int ret;
> +
> + INIT_WORK(&chip->cable.work, bq24261_extcon_event_work);
> + chip->cable.nb.notifier_call = bq24261_handle_extcon_events;
> +
> + ret = extcon_register_interest(&chip->cable.sdp, NULL,
> + "SLOW-CHARGER", &chip->cable.nb);
> + if (ret < 0) {
> + dev_warn(&chip->client->dev,
> + "extcon SDP registration failed(%d)\n", ret);
> + goto sdp_reg_failed;
> + }
> +
> + ret = extcon_register_interest(&chip->cable.cdp, NULL,
> + "CHARGE-DOWNSTREAM", &chip->cable.nb);
> + if (ret < 0) {
> + dev_warn(&chip->client->dev,
> + "extcon CDP registration failed(%d)\n", ret);
> + goto cdp_reg_failed;
> + }
> +
> + ret = extcon_register_interest(&chip->cable.dcp, NULL,
> + "FAST-CHARGER", &chip->cable.nb);
> + if (ret < 0) {
> + dev_warn(&chip->client->dev,
> + "extcon DCP registration failed(%d)\n", ret);
> + goto dcp_reg_failed;
> + }
> +
> + ret = extcon_register_interest(&chip->cable.otg, NULL,
> + "USB-Host", &chip->cable.nb);
> + if (ret < 0) {
> + dev_warn(&chip->client->dev,
> + "extcon USB-Host registration failed(%d)\n", ret);
> + goto otg_reg_failed;
> + }
> +
> + return 0;
> +
> +otg_reg_failed:
> + extcon_unregister_interest(&chip->cable.dcp);
> +dcp_reg_failed:
> + extcon_unregister_interest(&chip->cable.cdp);
> +cdp_reg_failed:
> + extcon_unregister_interest(&chip->cable.sdp);
> +sdp_reg_failed:
> + return -EPROBE_DEFER;
> +}
> +
> +static void bq24261_of_pdata(struct bq24261_charger *chip)

Why _of_ in the name? Unified device property interface makes it
independent on fw.

> +{
> + static struct bq24261_platform_data pdata;
> + struct device *dev = &chip->client->dev;
> + int ret, val;
> +
> + ret = device_property_read_u32(dev,
> + "ti,charge-current", &val);
> + if (ret < 0)
> + goto of_err;
> + pdata.def_cc = val / 1000;
> +
> + ret = device_property_read_u32(dev,
> + "ti,battery-regulation-voltage", &val);
> + if (ret < 0)
> + goto of_err;
> + pdata.def_cv = val / 1000;
> +
> + ret = device_property_read_u32(dev,
> + "ti,termination-current", &val);
> + if (ret < 0)
> + goto of_err;
> + pdata.iterm = val / 1000;
> +
> + /* get optional parameters */
> + ret = device_property_read_u32(dev,
> + "ti,max-charge-current", &val);
> + if (ret < 0)
> + pdata.max_cc = BQ24261_MAX_CC;
> + else
> + pdata.max_cc = val / 1000;
> +
> + ret = device_property_read_u32(dev,
> + "ti,max-charge-voltage", &val);
> + if (ret < 0)
> + pdata.max_cc = BQ24261_MAX_CV;
> + else
> + pdata.max_cv = val / 1000;
> +
> + ret = device_property_read_u32(dev,
> + "ti,min-charge-temperature", &val);
> + if (ret < 0)
> + pdata.min_temp = BQ24261_MIN_TEMP;
> + else
> + pdata.min_temp = val;
> +
> + ret = device_property_read_u32(dev,
> + "ti,max-charge-temperature", &val);
> + if (ret < 0)
> + pdata.max_temp = BQ24261_MAX_TEMP;
> + else
> + pdata.max_temp = val;
> +
> + ret = device_property_read_u32(dev,
> + "ti,thermal-sensing", &val);
> + if (ret < 0)
> + pdata.thermal_sensing = 0;
> + else
> + pdata.thermal_sensing = val;
> +
> + chip->pdata = &pdata;
> +
> + return;
> +of_err:
> + dev_err(dev, "error in getting DT property(%d)\n", ret);

No of_ and DT, it looks and behaves independently.

> +}
> +
> +static int bq24261_get_model(struct i2c_client *client,
> + enum bq2426x_model *model)
> +{
> + int ret;
> +
> + ret = bq24261_read_reg(client, BQ24261_VENDOR_REV_ADDR);
> + if (ret < 0)
> + return ret;
> +
> + *model = BQ24261;
> +
> + return 0;
> +}
> +
> +static int bq24261_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
> + struct power_supply_config charger_cfg = {};
> + struct bq24261_charger *chip;
> + int ret;
> + enum bq2426x_model model;
> +
> + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
> + dev_err(&client->dev,
> + "I2C adapter %s doesn'tsupport BYTE DATA transfer\n",
> + adapter->name);
> + return -EIO;
> + }
> +
> + ret = bq24261_get_model(client, &model);
> + if (ret < 0) {
> + dev_err(&client->dev, "chip detection error (%d)\n", ret);
> + return -ENODEV;
> + }
> +
> + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
> + if (!chip)
> + return -ENOMEM;
> +
> + chip->client = client;
> + if (client->dev.platform_data)
> + chip->pdata = client->dev.platform_data;
> + else if (id->driver_data)
> + chip->pdata = (struct bq24261_platform_data *)id->driver_data;
> + else
> + bq24261_of_pdata(chip);
> +
> + if (!chip->pdata) {
> + dev_err(&client->dev, "platform data not found");
> + return -ENODEV;
> + }
> +
> + i2c_set_clientdata(client, chip);
> + mutex_init(&chip->lock);
> + chip->model = model;
> +
> + /* Initialize charger parameters */
> + chip->cc = chip->pdata->def_cc;
> + chip->cv = chip->pdata->def_cv;
> + chip->iterm = chip->pdata->iterm;
> + chip->chg_status = BQ24261_CHRGR_STAT_UNKNOWN;
> + chip->chg_health = POWER_SUPPLY_HEALTH_UNKNOWN;
> +
> + charger_cfg.drv_data = chip;
> + charger_cfg.supplied_to = bq24261_charger_supplied_to;
> + charger_cfg.num_supplicants = ARRAY_SIZE(bq24261_charger_supplied_to);
> + if (!dis_sysfs_write) {
> + bq24261_charger_desc.set_property = bq24261_usb_set_property;
> + bq24261_charger_desc.property_is_writeable =
> + bq24261_property_is_writeable;
> + }
> + chip->psy_usb = power_supply_register(&client->dev,
> + &bq24261_charger_desc, &charger_cfg);
> + if (IS_ERR(chip->psy_usb)) {
> + dev_err(&client->dev, "power supply registration failed(%d)\n",
> + IS_ERR(chip->psy_usb));
> + return IS_ERR(chip->psy_usb);
> + }
> +
> + INIT_DELAYED_WORK(&chip->wdt_work, bq24261_wdt_reset_worker);
> + INIT_DELAYED_WORK(&chip->fault_mon_work, bq24261_fault_mon_work);
> +
> + ret = bq24261_extcon_register(chip);
> + if (ret < 0)
> + goto extcon_reg_failed;
> +
> + if (chip->client->irq) {
> + ret = devm_request_threaded_irq(&client->dev, chip->client->irq,
> + NULL, bq24261_thread_handler,
> + IRQF_SHARED | IRQF_NO_SUSPEND,
> + DEV_NAME, chip);
> + if (ret) {
> + dev_err(&client->dev,
> + "irq request failed (%d)\n", ret);
> + goto irq_reg_failed;
> + }
> + INIT_WORK(&chip->irq_work, bq24261_irq_worker);
> + }
> +
> + /* Check for charger connected boot case */
> + schedule_work(&chip->cable.work);
> +
> + return 0;
> +
> +irq_reg_failed:
> + extcon_unregister_interest(&chip->cable.sdp);
> + extcon_unregister_interest(&chip->cable.cdp);
> + extcon_unregister_interest(&chip->cable.dcp);
> + extcon_unregister_interest(&chip->cable.otg);
> +extcon_reg_failed:
> + power_supply_unregister(chip->psy_usb);
> + return ret;
> +}
> +
> +static int bq24261_remove(struct i2c_client *client)
> +{
> + struct bq24261_charger *chip = i2c_get_clientdata(client);
> +
> + flush_scheduled_work();
> + extcon_unregister_interest(&chip->cable.sdp);
> + extcon_unregister_interest(&chip->cable.cdp);
> + extcon_unregister_interest(&chip->cable.dcp);
> + extcon_unregister_interest(&chip->cable.otg);
> + power_supply_unregister(chip->psy_usb);
> + return 0;
> +}
> +
> +static const struct i2c_device_id bq24261_id[] = {
> + {"bq24261", 0},
> + { },
> +};
> +MODULE_DEVICE_TABLE(i2c, bq24261_id);
> +
> +static const struct acpi_device_id bq24261_acpi_match[] = {
> + {"TBQ24261", 0},
> + {},
> +};
> +MODULE_DEVICE_TABLE(acpi, bq24261_acpi_match);
> +
> +static const struct of_device_id bq24261_of_match[] = {
> + { .compatible = "ti,bq24261", },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, bq24261_of_match);
> +
> +static struct i2c_driver bq24261_driver = {
> + .driver = {
> + .name = DEV_NAME,
> + .acpi_match_table = ACPI_PTR(bq24261_acpi_match),
> + .of_match_table = of_match_ptr(bq24261_of_match),
> + },
> + .probe = bq24261_probe,
> + .remove = bq24261_remove,
> + .id_table = bq24261_id,
> +};
> +
> +module_i2c_driver(bq24261_driver);
> +
> +MODULE_AUTHOR("Jenny TC <jenny.tc@xxxxxxxxx>");
> +MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@xxxxxxxxx>");
> +MODULE_DESCRIPTION("BQ24261 Charger Driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/power/bq24261_charger.h b/include/linux/power/bq24261_charger.h
> new file mode 100644
> index 0000000..6c7d96e
> --- /dev/null
> +++ b/include/linux/power/bq24261_charger.h
> @@ -0,0 +1,26 @@
> +/*
> + * bq24261_charger.h: platform data structure for bq24261 driver
> + *
> + * Copyright (C) 2014 Intel Corporation
> + *
> + * 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; version 2
> + * of the License.
> + */
> +
> +#ifndef __BQ24261_CHARGER_H__
> +#define __BQ24261_CHARGER_H__
> +
> +struct bq24261_platform_data {
> + int def_cc; /* in mA */
> + int def_cv; /* in mV */
> + int iterm; /* in mA */
> + int max_cc; /* in mA */
> + int max_cv; /* in mV */
> + int min_temp; /* in DegC */
> + int max_temp; /* in DegC */
> + int thermal_sensing;
> +};
> +
> +#endif
> --
> 1.7.9.5
>
> --
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--
With Best Regards,
Andy Shevchenko
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