648 lines
16 KiB
C
648 lines
16 KiB
C
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// SPDX-License-Identifier: GPL-2.0-only
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/*
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* I2C client/driver for the Linear Technology LTC2941, LTC2942, LTC2943
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* and LTC2944 Battery Gas Gauge IC
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*
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* Copyright (C) 2014 Topic Embedded Systems
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*
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* Author: Auryn Verwegen
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* Author: Mike Looijmans
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*/
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#include <linux/devm-helpers.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/of_device.h>
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#include <linux/types.h>
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#include <linux/errno.h>
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#include <linux/swab.h>
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#include <linux/i2c.h>
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#include <linux/delay.h>
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#include <linux/power_supply.h>
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#include <linux/slab.h>
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#define I16_MSB(x) ((x >> 8) & 0xFF)
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#define I16_LSB(x) (x & 0xFF)
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#define LTC294X_WORK_DELAY 10 /* Update delay in seconds */
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#define LTC294X_MAX_VALUE 0xFFFF
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#define LTC294X_MID_SUPPLY 0x7FFF
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#define LTC2941_MAX_PRESCALER_EXP 7
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#define LTC2943_MAX_PRESCALER_EXP 6
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enum ltc294x_reg {
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LTC294X_REG_STATUS = 0x00,
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LTC294X_REG_CONTROL = 0x01,
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LTC294X_REG_ACC_CHARGE_MSB = 0x02,
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LTC294X_REG_ACC_CHARGE_LSB = 0x03,
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LTC294X_REG_CHARGE_THR_HIGH_MSB = 0x04,
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LTC294X_REG_CHARGE_THR_HIGH_LSB = 0x05,
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LTC294X_REG_CHARGE_THR_LOW_MSB = 0x06,
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LTC294X_REG_CHARGE_THR_LOW_LSB = 0x07,
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LTC294X_REG_VOLTAGE_MSB = 0x08,
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LTC294X_REG_VOLTAGE_LSB = 0x09,
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LTC2942_REG_TEMPERATURE_MSB = 0x0C,
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LTC2942_REG_TEMPERATURE_LSB = 0x0D,
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LTC2943_REG_CURRENT_MSB = 0x0E,
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LTC2943_REG_CURRENT_LSB = 0x0F,
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LTC2943_REG_TEMPERATURE_MSB = 0x14,
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LTC2943_REG_TEMPERATURE_LSB = 0x15,
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};
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enum ltc294x_id {
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LTC2941_ID,
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LTC2942_ID,
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LTC2943_ID,
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LTC2944_ID,
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};
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#define LTC2941_REG_STATUS_CHIP_ID BIT(7)
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#define LTC2942_REG_CONTROL_MODE_SCAN (BIT(7) | BIT(6))
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#define LTC2943_REG_CONTROL_MODE_SCAN BIT(7)
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#define LTC294X_REG_CONTROL_PRESCALER_MASK (BIT(5) | BIT(4) | BIT(3))
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#define LTC294X_REG_CONTROL_SHUTDOWN_MASK (BIT(0))
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#define LTC294X_REG_CONTROL_PRESCALER_SET(x) \
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((x << 3) & LTC294X_REG_CONTROL_PRESCALER_MASK)
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#define LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED 0
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#define LTC294X_REG_CONTROL_ADC_DISABLE(x) ((x) & ~(BIT(7) | BIT(6)))
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struct ltc294x_info {
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struct i2c_client *client; /* I2C Client pointer */
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struct power_supply *supply; /* Supply pointer */
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struct power_supply_desc supply_desc; /* Supply description */
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struct delayed_work work; /* Work scheduler */
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enum ltc294x_id id; /* Chip type */
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int charge; /* Last charge register content */
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int r_sense; /* mOhm */
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int Qlsb; /* nAh */
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};
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static inline int convert_bin_to_uAh(
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const struct ltc294x_info *info, int Q)
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{
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return ((Q * (info->Qlsb / 10))) / 100;
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}
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static inline int convert_uAh_to_bin(
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const struct ltc294x_info *info, int uAh)
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{
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int Q;
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Q = (uAh * 100) / (info->Qlsb/10);
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return (Q < LTC294X_MAX_VALUE) ? Q : LTC294X_MAX_VALUE;
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}
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static int ltc294x_read_regs(struct i2c_client *client,
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enum ltc294x_reg reg, u8 *buf, int num_regs)
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{
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int ret;
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struct i2c_msg msgs[2] = { };
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u8 reg_start = reg;
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msgs[0].addr = client->addr;
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msgs[0].len = 1;
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msgs[0].buf = ®_start;
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msgs[1].addr = client->addr;
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msgs[1].len = num_regs;
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msgs[1].buf = buf;
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msgs[1].flags = I2C_M_RD;
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ret = i2c_transfer(client->adapter, &msgs[0], 2);
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if (ret < 0) {
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dev_err(&client->dev, "ltc2941 read_reg(0x%x[%d]) failed: %pe\n",
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reg, num_regs, ERR_PTR(ret));
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return ret;
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}
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dev_dbg(&client->dev, "%s (%#x, %d) -> %#x\n",
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__func__, reg, num_regs, *buf);
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return 0;
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}
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static int ltc294x_write_regs(struct i2c_client *client,
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enum ltc294x_reg reg, const u8 *buf, int num_regs)
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{
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int ret;
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u8 reg_start = reg;
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ret = i2c_smbus_write_i2c_block_data(client, reg_start, num_regs, buf);
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if (ret < 0) {
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dev_err(&client->dev, "ltc2941 write_reg(0x%x[%d]) failed: %pe\n",
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reg, num_regs, ERR_PTR(ret));
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return ret;
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}
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dev_dbg(&client->dev, "%s (%#x, %d) -> %#x\n",
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__func__, reg, num_regs, *buf);
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return 0;
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}
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static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
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{
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int ret;
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u8 value;
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u8 control;
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/* Read status and control registers */
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ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
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if (ret < 0)
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return ret;
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control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
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LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED;
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/* Put device into "monitor" mode */
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switch (info->id) {
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case LTC2942_ID: /* 2942 measures every 2 sec */
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control |= LTC2942_REG_CONTROL_MODE_SCAN;
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break;
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case LTC2943_ID:
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case LTC2944_ID: /* 2943 and 2944 measure every 10 sec */
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control |= LTC2943_REG_CONTROL_MODE_SCAN;
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break;
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default:
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break;
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}
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if (value != control) {
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_CONTROL, &control, 1);
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if (ret < 0)
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return ret;
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}
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return 0;
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}
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static int ltc294x_read_charge_register(const struct ltc294x_info *info,
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enum ltc294x_reg reg)
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{
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int ret;
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u8 datar[2];
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ret = ltc294x_read_regs(info->client, reg, &datar[0], 2);
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if (ret < 0)
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return ret;
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return (datar[0] << 8) + datar[1];
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}
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static int ltc294x_get_charge(const struct ltc294x_info *info,
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enum ltc294x_reg reg, int *val)
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{
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int value = ltc294x_read_charge_register(info, reg);
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if (value < 0)
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return value;
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/* When r_sense < 0, this counts up when the battery discharges */
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if (info->Qlsb < 0)
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value -= 0xFFFF;
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*val = convert_bin_to_uAh(info, value);
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return 0;
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}
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static int ltc294x_set_charge_now(const struct ltc294x_info *info, int val)
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{
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int ret;
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u8 dataw[2];
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u8 ctrl_reg;
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s32 value;
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value = convert_uAh_to_bin(info, val);
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/* Direction depends on how sense+/- were connected */
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if (info->Qlsb < 0)
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value += 0xFFFF;
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if ((value < 0) || (value > 0xFFFF)) /* input validation */
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return -EINVAL;
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/* Read control register */
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ret = ltc294x_read_regs(info->client,
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LTC294X_REG_CONTROL, &ctrl_reg, 1);
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if (ret < 0)
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return ret;
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/* Disable analog section */
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ctrl_reg |= LTC294X_REG_CONTROL_SHUTDOWN_MASK;
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_CONTROL, &ctrl_reg, 1);
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if (ret < 0)
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return ret;
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/* Set new charge value */
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dataw[0] = I16_MSB(value);
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dataw[1] = I16_LSB(value);
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_ACC_CHARGE_MSB, &dataw[0], 2);
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if (ret < 0)
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goto error_exit;
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/* Enable analog section */
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error_exit:
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ctrl_reg &= ~LTC294X_REG_CONTROL_SHUTDOWN_MASK;
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_CONTROL, &ctrl_reg, 1);
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return ret < 0 ? ret : 0;
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}
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static int ltc294x_set_charge_thr(const struct ltc294x_info *info,
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enum ltc294x_reg reg, int val)
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{
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u8 dataw[2];
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s32 value;
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value = convert_uAh_to_bin(info, val);
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/* Direction depends on how sense+/- were connected */
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if (info->Qlsb < 0)
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value += 0xFFFF;
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if ((value < 0) || (value > 0xFFFF)) /* input validation */
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return -EINVAL;
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/* Set new charge value */
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dataw[0] = I16_MSB(value);
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dataw[1] = I16_LSB(value);
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return ltc294x_write_regs(info->client, reg, &dataw[0], 2);
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}
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static int ltc294x_get_charge_counter(
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const struct ltc294x_info *info, int *val)
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{
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int value = ltc294x_read_charge_register(info, LTC294X_REG_ACC_CHARGE_MSB);
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if (value < 0)
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return value;
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value -= LTC294X_MID_SUPPLY;
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*val = convert_bin_to_uAh(info, value);
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return 0;
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}
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static int ltc294x_get_voltage(const struct ltc294x_info *info, int *val)
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{
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int ret;
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u8 datar[2];
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u32 value;
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ret = ltc294x_read_regs(info->client,
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LTC294X_REG_VOLTAGE_MSB, &datar[0], 2);
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value = (datar[0] << 8) | datar[1];
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switch (info->id) {
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case LTC2943_ID:
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value *= 23600 * 2;
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value /= 0xFFFF;
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value *= 1000 / 2;
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break;
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case LTC2944_ID:
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value *= 70800 / 5*4;
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value /= 0xFFFF;
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value *= 1000 * 5/4;
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break;
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default:
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value *= 6000 * 10;
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value /= 0xFFFF;
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value *= 1000 / 10;
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break;
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}
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*val = value;
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return ret;
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}
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static int ltc294x_get_current(const struct ltc294x_info *info, int *val)
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{
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int ret;
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u8 datar[2];
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s32 value;
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ret = ltc294x_read_regs(info->client,
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LTC2943_REG_CURRENT_MSB, &datar[0], 2);
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value = (datar[0] << 8) | datar[1];
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value -= 0x7FFF;
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if (info->id == LTC2944_ID)
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value *= 64000;
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else
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value *= 60000;
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/* Value is in range -32k..+32k, r_sense is usually 10..50 mOhm,
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* the formula below keeps everything in s32 range while preserving
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* enough digits */
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*val = 1000 * (value / (info->r_sense * 0x7FFF)); /* in uA */
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return ret;
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}
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static int ltc294x_get_temperature(const struct ltc294x_info *info, int *val)
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{
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enum ltc294x_reg reg;
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int ret;
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u8 datar[2];
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u32 value;
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if (info->id == LTC2942_ID) {
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reg = LTC2942_REG_TEMPERATURE_MSB;
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value = 6000; /* Full-scale is 600 Kelvin */
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} else {
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reg = LTC2943_REG_TEMPERATURE_MSB;
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value = 5100; /* Full-scale is 510 Kelvin */
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}
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ret = ltc294x_read_regs(info->client, reg, &datar[0], 2);
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value *= (datar[0] << 8) | datar[1];
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/* Convert to tenths of degree Celsius */
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*val = value / 0xFFFF - 2722;
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return ret;
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}
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static int ltc294x_get_property(struct power_supply *psy,
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enum power_supply_property prop,
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union power_supply_propval *val)
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{
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struct ltc294x_info *info = power_supply_get_drvdata(psy);
|
||
|
|
|
||
|
|
switch (prop) {
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_FULL:
|
||
|
|
return ltc294x_get_charge(info, LTC294X_REG_CHARGE_THR_HIGH_MSB,
|
||
|
|
&val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_EMPTY:
|
||
|
|
return ltc294x_get_charge(info, LTC294X_REG_CHARGE_THR_LOW_MSB,
|
||
|
|
&val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_NOW:
|
||
|
|
return ltc294x_get_charge(info, LTC294X_REG_ACC_CHARGE_MSB,
|
||
|
|
&val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_COUNTER:
|
||
|
|
return ltc294x_get_charge_counter(info, &val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
|
||
|
|
return ltc294x_get_voltage(info, &val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_CURRENT_NOW:
|
||
|
|
return ltc294x_get_current(info, &val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_TEMP:
|
||
|
|
return ltc294x_get_temperature(info, &val->intval);
|
||
|
|
default:
|
||
|
|
return -EINVAL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ltc294x_set_property(struct power_supply *psy,
|
||
|
|
enum power_supply_property psp,
|
||
|
|
const union power_supply_propval *val)
|
||
|
|
{
|
||
|
|
struct ltc294x_info *info = power_supply_get_drvdata(psy);
|
||
|
|
|
||
|
|
switch (psp) {
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_FULL:
|
||
|
|
return ltc294x_set_charge_thr(info,
|
||
|
|
LTC294X_REG_CHARGE_THR_HIGH_MSB, val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_EMPTY:
|
||
|
|
return ltc294x_set_charge_thr(info,
|
||
|
|
LTC294X_REG_CHARGE_THR_LOW_MSB, val->intval);
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_NOW:
|
||
|
|
return ltc294x_set_charge_now(info, val->intval);
|
||
|
|
default:
|
||
|
|
return -EPERM;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ltc294x_property_is_writeable(
|
||
|
|
struct power_supply *psy, enum power_supply_property psp)
|
||
|
|
{
|
||
|
|
switch (psp) {
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_FULL:
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_EMPTY:
|
||
|
|
case POWER_SUPPLY_PROP_CHARGE_NOW:
|
||
|
|
return 1;
|
||
|
|
default:
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static void ltc294x_update(struct ltc294x_info *info)
|
||
|
|
{
|
||
|
|
int charge = ltc294x_read_charge_register(info, LTC294X_REG_ACC_CHARGE_MSB);
|
||
|
|
|
||
|
|
if (charge != info->charge) {
|
||
|
|
info->charge = charge;
|
||
|
|
power_supply_changed(info->supply);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static void ltc294x_work(struct work_struct *work)
|
||
|
|
{
|
||
|
|
struct ltc294x_info *info;
|
||
|
|
|
||
|
|
info = container_of(work, struct ltc294x_info, work.work);
|
||
|
|
ltc294x_update(info);
|
||
|
|
schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
|
||
|
|
}
|
||
|
|
|
||
|
|
static enum power_supply_property ltc294x_properties[] = {
|
||
|
|
POWER_SUPPLY_PROP_CHARGE_COUNTER,
|
||
|
|
POWER_SUPPLY_PROP_CHARGE_FULL,
|
||
|
|
POWER_SUPPLY_PROP_CHARGE_EMPTY,
|
||
|
|
POWER_SUPPLY_PROP_CHARGE_NOW,
|
||
|
|
POWER_SUPPLY_PROP_VOLTAGE_NOW,
|
||
|
|
POWER_SUPPLY_PROP_TEMP,
|
||
|
|
POWER_SUPPLY_PROP_CURRENT_NOW,
|
||
|
|
};
|
||
|
|
|
||
|
|
static int ltc294x_i2c_probe(struct i2c_client *client)
|
||
|
|
{
|
||
|
|
struct power_supply_config psy_cfg = {};
|
||
|
|
struct ltc294x_info *info;
|
||
|
|
struct device_node *np;
|
||
|
|
int ret;
|
||
|
|
u32 prescaler_exp;
|
||
|
|
s32 r_sense;
|
||
|
|
u8 status;
|
||
|
|
|
||
|
|
info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
|
||
|
|
if (info == NULL)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
i2c_set_clientdata(client, info);
|
||
|
|
|
||
|
|
np = of_node_get(client->dev.of_node);
|
||
|
|
|
||
|
|
info->id = (enum ltc294x_id) (uintptr_t) of_device_get_match_data(
|
||
|
|
&client->dev);
|
||
|
|
info->supply_desc.name = np->name;
|
||
|
|
|
||
|
|
/* r_sense can be negative, when sense+ is connected to the battery
|
||
|
|
* instead of the sense-. This results in reversed measurements. */
|
||
|
|
ret = of_property_read_u32(np, "lltc,resistor-sense", &r_sense);
|
||
|
|
if (ret < 0)
|
||
|
|
return dev_err_probe(&client->dev, ret,
|
||
|
|
"Could not find lltc,resistor-sense in devicetree\n");
|
||
|
|
info->r_sense = r_sense;
|
||
|
|
|
||
|
|
ret = of_property_read_u32(np, "lltc,prescaler-exponent",
|
||
|
|
&prescaler_exp);
|
||
|
|
if (ret < 0) {
|
||
|
|
dev_warn(&client->dev,
|
||
|
|
"lltc,prescaler-exponent not in devicetree\n");
|
||
|
|
prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (info->id == LTC2943_ID) {
|
||
|
|
if (prescaler_exp > LTC2943_MAX_PRESCALER_EXP)
|
||
|
|
prescaler_exp = LTC2943_MAX_PRESCALER_EXP;
|
||
|
|
info->Qlsb = ((340 * 50000) / r_sense) >>
|
||
|
|
(12 - 2*prescaler_exp);
|
||
|
|
} else {
|
||
|
|
if (prescaler_exp > LTC2941_MAX_PRESCALER_EXP)
|
||
|
|
prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
|
||
|
|
info->Qlsb = ((85 * 50000) / r_sense) >>
|
||
|
|
(7 - prescaler_exp);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Read status register to check for LTC2942 */
|
||
|
|
if (info->id == LTC2941_ID || info->id == LTC2942_ID) {
|
||
|
|
ret = ltc294x_read_regs(client, LTC294X_REG_STATUS, &status, 1);
|
||
|
|
if (ret < 0)
|
||
|
|
return dev_err_probe(&client->dev, ret,
|
||
|
|
"Could not read status register\n");
|
||
|
|
if (status & LTC2941_REG_STATUS_CHIP_ID)
|
||
|
|
info->id = LTC2941_ID;
|
||
|
|
else
|
||
|
|
info->id = LTC2942_ID;
|
||
|
|
}
|
||
|
|
|
||
|
|
info->client = client;
|
||
|
|
info->supply_desc.type = POWER_SUPPLY_TYPE_BATTERY;
|
||
|
|
info->supply_desc.properties = ltc294x_properties;
|
||
|
|
switch (info->id) {
|
||
|
|
case LTC2944_ID:
|
||
|
|
case LTC2943_ID:
|
||
|
|
info->supply_desc.num_properties =
|
||
|
|
ARRAY_SIZE(ltc294x_properties);
|
||
|
|
break;
|
||
|
|
case LTC2942_ID:
|
||
|
|
info->supply_desc.num_properties =
|
||
|
|
ARRAY_SIZE(ltc294x_properties) - 1;
|
||
|
|
break;
|
||
|
|
case LTC2941_ID:
|
||
|
|
default:
|
||
|
|
info->supply_desc.num_properties =
|
||
|
|
ARRAY_SIZE(ltc294x_properties) - 3;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
info->supply_desc.get_property = ltc294x_get_property;
|
||
|
|
info->supply_desc.set_property = ltc294x_set_property;
|
||
|
|
info->supply_desc.property_is_writeable = ltc294x_property_is_writeable;
|
||
|
|
info->supply_desc.external_power_changed = NULL;
|
||
|
|
|
||
|
|
psy_cfg.drv_data = info;
|
||
|
|
|
||
|
|
ret = devm_delayed_work_autocancel(&client->dev, &info->work,
|
||
|
|
ltc294x_work);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
ret = ltc294x_reset(info, prescaler_exp);
|
||
|
|
if (ret < 0)
|
||
|
|
return dev_err_probe(&client->dev, ret,
|
||
|
|
"Communication with chip failed\n");
|
||
|
|
|
||
|
|
info->supply = devm_power_supply_register(&client->dev,
|
||
|
|
&info->supply_desc, &psy_cfg);
|
||
|
|
if (IS_ERR(info->supply))
|
||
|
|
return dev_err_probe(&client->dev, PTR_ERR(info->supply),
|
||
|
|
"failed to register ltc2941\n");
|
||
|
|
|
||
|
|
schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void ltc294x_i2c_shutdown(struct i2c_client *client)
|
||
|
|
{
|
||
|
|
struct ltc294x_info *info = i2c_get_clientdata(client);
|
||
|
|
int ret;
|
||
|
|
u8 value;
|
||
|
|
u8 control;
|
||
|
|
|
||
|
|
/* The LTC2941 does not need any special handling */
|
||
|
|
if (info->id == LTC2941_ID)
|
||
|
|
return;
|
||
|
|
|
||
|
|
/* Read control register */
|
||
|
|
ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
|
||
|
|
if (ret < 0)
|
||
|
|
return;
|
||
|
|
|
||
|
|
/* Disable continuous ADC conversion as this drains the battery */
|
||
|
|
control = LTC294X_REG_CONTROL_ADC_DISABLE(value);
|
||
|
|
if (control != value)
|
||
|
|
ltc294x_write_regs(info->client, LTC294X_REG_CONTROL,
|
||
|
|
&control, 1);
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef CONFIG_PM_SLEEP
|
||
|
|
|
||
|
|
static int ltc294x_suspend(struct device *dev)
|
||
|
|
{
|
||
|
|
struct i2c_client *client = to_i2c_client(dev);
|
||
|
|
struct ltc294x_info *info = i2c_get_clientdata(client);
|
||
|
|
|
||
|
|
cancel_delayed_work(&info->work);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ltc294x_resume(struct device *dev)
|
||
|
|
{
|
||
|
|
struct i2c_client *client = to_i2c_client(dev);
|
||
|
|
struct ltc294x_info *info = i2c_get_clientdata(client);
|
||
|
|
|
||
|
|
schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static SIMPLE_DEV_PM_OPS(ltc294x_pm_ops, ltc294x_suspend, ltc294x_resume);
|
||
|
|
#define LTC294X_PM_OPS (<c294x_pm_ops)
|
||
|
|
|
||
|
|
#else
|
||
|
|
#define LTC294X_PM_OPS NULL
|
||
|
|
#endif /* CONFIG_PM_SLEEP */
|
||
|
|
|
||
|
|
|
||
|
|
static const struct i2c_device_id ltc294x_i2c_id[] = {
|
||
|
|
{ "ltc2941", LTC2941_ID, },
|
||
|
|
{ "ltc2942", LTC2942_ID, },
|
||
|
|
{ "ltc2943", LTC2943_ID, },
|
||
|
|
{ "ltc2944", LTC2944_ID, },
|
||
|
|
{ },
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(i2c, ltc294x_i2c_id);
|
||
|
|
|
||
|
|
static const struct of_device_id ltc294x_i2c_of_match[] = {
|
||
|
|
{
|
||
|
|
.compatible = "lltc,ltc2941",
|
||
|
|
.data = (void *)LTC2941_ID,
|
||
|
|
},
|
||
|
|
{
|
||
|
|
.compatible = "lltc,ltc2942",
|
||
|
|
.data = (void *)LTC2942_ID,
|
||
|
|
},
|
||
|
|
{
|
||
|
|
.compatible = "lltc,ltc2943",
|
||
|
|
.data = (void *)LTC2943_ID,
|
||
|
|
},
|
||
|
|
{
|
||
|
|
.compatible = "lltc,ltc2944",
|
||
|
|
.data = (void *)LTC2944_ID,
|
||
|
|
},
|
||
|
|
{ },
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(of, ltc294x_i2c_of_match);
|
||
|
|
|
||
|
|
static struct i2c_driver ltc294x_driver = {
|
||
|
|
.driver = {
|
||
|
|
.name = "LTC2941",
|
||
|
|
.of_match_table = ltc294x_i2c_of_match,
|
||
|
|
.pm = LTC294X_PM_OPS,
|
||
|
|
},
|
||
|
|
.probe_new = ltc294x_i2c_probe,
|
||
|
|
.shutdown = ltc294x_i2c_shutdown,
|
||
|
|
.id_table = ltc294x_i2c_id,
|
||
|
|
};
|
||
|
|
module_i2c_driver(ltc294x_driver);
|
||
|
|
|
||
|
|
MODULE_AUTHOR("Auryn Verwegen, Topic Embedded Systems");
|
||
|
|
MODULE_AUTHOR("Mike Looijmans, Topic Embedded Products");
|
||
|
|
MODULE_DESCRIPTION("LTC2941/LTC2942/LTC2943/LTC2944 Battery Gas Gauge IC driver");
|
||
|
|
MODULE_LICENSE("GPL");
|