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[209.132.180.67]) by mx.google.com with ESMTP id 64-v6si1282496plk.257.2018.09.27.00.28.06; Thu, 27 Sep 2018 00:28:07 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of devicetree-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=P21zi9Sr; spf=pass (google.com: best guess record for domain of devicetree-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=devicetree-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727303AbeI0No4 (ORCPT + 6 others); Thu, 27 Sep 2018 09:44:56 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:36967 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727241AbeI0No4 (ORCPT ); Thu, 27 Sep 2018 09:44:56 -0400 Received: by mail-pg1-f194.google.com with SMTP id c10-v6so1271319pgq.4 for ; Thu, 27 Sep 2018 00:28:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :in-reply-to:references; bh=x/bf2B1O28GlgKGBsL6ZOOMbTs1zvo6PdwDnoQ9v8SI=; b=P21zi9SroQP4SXIEgEKFLBdEGFu231uF0aKnJLyNMhhgTkxu5m61hZtU5PsMx6HPvs 4t+FeS/GuRqfdf/2rVyymJtM4SxCJj3i1q7WZXagDr3+Yq/t0ypcOGNgxMKAtDdnB3/R TYf1lFouRJtSrQLHgoJre1bMFxw1ywTznLHfc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:in-reply-to:references; bh=x/bf2B1O28GlgKGBsL6ZOOMbTs1zvo6PdwDnoQ9v8SI=; b=ZXVsxKK9azxwRvMi1Igz5V3bqS2aTr1VnmZBzDc4m24gZRBxJPSdcHeQpkELaJ/ttc x+DDaRTwcWDypLQLpPe36u6UpSopX06OcuKNeFr3ba0LCUyx43uUqrohsEv404watQUu KD5Yv0X5UKh2bKhDLPu9azfnwbjBDG+5WfpnDr7+y9zxg91zNrUUxTyUdQB2pPDrA2s5 lqnWEKlRaKNOInWDCvMl88b1CldRl27CEtlm0Kk7KBEXs+3+ARolL+kyaYezjnHOBXZ7 aCkbH04rdIdWmIl4j+6Bw0Vm35TVcumbqKVD8co4gz7P437yQbpG+xY8UNQ8UySyshfz MmvQ== X-Gm-Message-State: ABuFfog4/pwmWm2F2YCFxZh+CHB3YrqeyVci55bqRiTevhmLKT10CmQ5 DoYirbuRy6Mp4XgczBwpJUb9cQ== X-Received: by 2002:a63:525c:: with SMTP id s28-v6mr8835814pgl.78.1538033284358; Thu, 27 Sep 2018 00:28:04 -0700 (PDT) Received: from baolinwangubtpc.spreadtrum.com ([117.18.48.102]) by smtp.gmail.com with ESMTPSA id h12-v6sm1835018pfo.135.2018.09.27.00.27.59 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 27 Sep 2018 00:28:03 -0700 (PDT) From: Baolin Wang To: sre@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, yuanjiang.yu@unisoc.com, baolin.wang@linaro.org, broonie@kernel.org, ctatlor97@gmail.com, linus.walleij@linaro.org Subject: [PATCH v3 4/4] power: supply: Add Spreadtrum SC27XX fuel gauge unit driver Date: Thu, 27 Sep 2018 15:26:57 +0800 Message-Id: X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <2787f18a0366576959557d05112a069dca982269.1538033078.git.baolin.wang@linaro.org> References: <2787f18a0366576959557d05112a069dca982269.1538033078.git.baolin.wang@linaro.org> In-Reply-To: <2787f18a0366576959557d05112a069dca982269.1538033078.git.baolin.wang@linaro.org> References: <2787f18a0366576959557d05112a069dca982269.1538033078.git.baolin.wang@linaro.org> Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This patch adds the Spreadtrum SC27XX serial PMICs fuel gauge support, which is used to calculate the battery capacity. Original-by: Yuanjiang Yu Signed-off-by: Baolin Wang Acked-by: Linus Walleij --- Changes from v2: - Use core helper functions to look up OCV capacity table. - Use device_property_read_u32() instead of of_property_read_u32(). - Add acked tag from Linus. Changes from v1: - Use battery standard properties to get internal resistance and ocv table. - Change devm_gpiod_get_optional() to devm_gpiod_get(). - Add power_supply_changed() when detecting battery present change. - Return micro volts for sc27xx_fgu_get_vbat_ocv(). --- drivers/power/supply/Kconfig | 7 + drivers/power/supply/Makefile | 1 + drivers/power/supply/sc27xx_fuel_gauge.c | 661 ++++++++++++++++++++++++++++++ 3 files changed, 669 insertions(+) create mode 100644 drivers/power/supply/sc27xx_fuel_gauge.c -- 1.7.9.5 diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig index f27cf07..917f4b7 100644 --- a/drivers/power/supply/Kconfig +++ b/drivers/power/supply/Kconfig @@ -652,4 +652,11 @@ config CHARGER_SC2731 Say Y here to enable support for battery charging with SC2731 PMIC chips. +config FUEL_GAUGE_SC27XX + tristate "Spreadtrum SC27XX fuel gauge driver" + depends on MFD_SC27XX_PMIC || COMPILE_TEST + help + Say Y here to enable support for fuel gauge with SC27XX + PMIC chips. + endif # POWER_SUPPLY diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile index 767105b..b731c2a 100644 --- a/drivers/power/supply/Makefile +++ b/drivers/power/supply/Makefile @@ -86,3 +86,4 @@ obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o +obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c new file mode 100644 index 0000000..1c0b856 --- /dev/null +++ b/drivers/power/supply/sc27xx_fuel_gauge.c @@ -0,0 +1,661 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Spreadtrum Communications Inc. + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* PMIC global control registers definition */ +#define SC27XX_MODULE_EN0 0xc08 +#define SC27XX_CLK_EN0 0xc18 +#define SC27XX_FGU_EN BIT(7) +#define SC27XX_FGU_RTC_EN BIT(6) + +/* FGU registers definition */ +#define SC27XX_FGU_START 0x0 +#define SC27XX_FGU_CONFIG 0x4 +#define SC27XX_FGU_ADC_CONFIG 0x8 +#define SC27XX_FGU_STATUS 0xc +#define SC27XX_FGU_INT_EN 0x10 +#define SC27XX_FGU_INT_CLR 0x14 +#define SC27XX_FGU_INT_STS 0x1c +#define SC27XX_FGU_VOLTAGE 0x20 +#define SC27XX_FGU_OCV 0x24 +#define SC27XX_FGU_POCV 0x28 +#define SC27XX_FGU_CURRENT 0x2c +#define SC27XX_FGU_CLBCNT_SETH 0x50 +#define SC27XX_FGU_CLBCNT_SETL 0x54 +#define SC27XX_FGU_CLBCNT_VALH 0x68 +#define SC27XX_FGU_CLBCNT_VALL 0x6c +#define SC27XX_FGU_CLBCNT_QMAXL 0x74 + +#define SC27XX_WRITE_SELCLB_EN BIT(0) +#define SC27XX_FGU_CLBCNT_MASK GENMASK(15, 0) +#define SC27XX_FGU_CLBCNT_SHIFT 16 + +#define SC27XX_FGU_1000MV_ADC 686 +#define SC27XX_FGU_1000MA_ADC 1372 +#define SC27XX_FGU_CUR_BASIC_ADC 8192 +#define SC27XX_FGU_SAMPLE_HZ 2 + +/* + * struct sc27xx_fgu_data: describe the FGU device + * @regmap: regmap for register access + * @dev: platform device + * @battery: battery power supply + * @base: the base offset for the controller + * @lock: protect the structure + * @gpiod: GPIO for battery detection + * @channel: IIO channel to get battery temperature + * @internal_resist: the battery internal resistance in mOhm + * @total_cap: the total capacity of the battery in mAh + * @init_cap: the initial capacity of the battery in mAh + * @init_clbcnt: the initial coulomb counter + * @max_volt: the maximum constant input voltage in millivolt + * @table_len: the capacity table length + * @cap_table: capacity table with corresponding ocv + */ +struct sc27xx_fgu_data { + struct regmap *regmap; + struct device *dev; + struct power_supply *battery; + u32 base; + struct mutex lock; + struct gpio_desc *gpiod; + struct iio_channel *channel; + bool bat_present; + int internal_resist; + int total_cap; + int init_cap; + int init_clbcnt; + int max_volt; + int table_len; + struct power_supply_battery_ocv_table *cap_table; +}; + +static const char * const sc27xx_charger_supply_name[] = { + "sc2731_charger", + "sc2720_charger", + "sc2721_charger", + "sc2723_charger", +}; + +static int sc27xx_fgu_adc_to_current(int adc) +{ + return (adc * 1000) / SC27XX_FGU_1000MA_ADC; +} + +static int sc27xx_fgu_adc_to_voltage(int adc) +{ + return (adc * 1000) / SC27XX_FGU_1000MV_ADC; +} + +/* + * When system boots on, we can not read battery capacity from coulomb + * registers, since now the coulomb registers are invalid. So we should + * calculate the battery open circuit voltage, and get current battery + * capacity according to the capacity table. + */ +static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap) +{ + int volt, cur, oci, ocv, ret; + + /* + * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved + * the first sampled open circuit current. + */ + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL, + &cur); + if (ret) + return ret; + + cur <<= 1; + oci = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC); + + /* + * Should get the OCV from SC27XX_FGU_POCV register at the system + * beginning. It is ADC values reading from registers which need to + * convert the corresponding voltage. + */ + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt); + if (ret) + return ret; + + volt = sc27xx_fgu_adc_to_voltage(volt); + ocv = volt - (oci * data->internal_resist) / 1000; + + /* + * Parse the capacity table to look up the correct capacity percent + * according to current battery's corresponding OCV values. + */ + *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len, + ocv); + + return 0; +} + +static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt) +{ + int ret; + + clbcnt *= SC27XX_FGU_SAMPLE_HZ; + + ret = regmap_update_bits(data->regmap, + data->base + SC27XX_FGU_CLBCNT_SETL, + SC27XX_FGU_CLBCNT_MASK, clbcnt); + if (ret) + return ret; + + ret = regmap_update_bits(data->regmap, + data->base + SC27XX_FGU_CLBCNT_SETH, + SC27XX_FGU_CLBCNT_MASK, + clbcnt >> SC27XX_FGU_CLBCNT_SHIFT); + if (ret) + return ret; + + return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START, + SC27XX_WRITE_SELCLB_EN, + SC27XX_WRITE_SELCLB_EN); +} + +static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt) +{ + int ccl, cch, ret; + + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL, + &ccl); + if (ret) + return ret; + + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH, + &cch); + if (ret) + return ret; + + *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK; + *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT; + *clb_cnt /= SC27XX_FGU_SAMPLE_HZ; + + return 0; +} + +static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap) +{ + int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp; + + /* Get current coulomb counters firstly */ + ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt); + if (ret) + return ret; + + delta_clbcnt = cur_clbcnt - data->init_clbcnt; + + /* + * Convert coulomb counter to delta capacity (mAh), and set multiplier + * as 100 to improve the precision. + */ + temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360); + temp = sc27xx_fgu_adc_to_current(temp); + + /* + * Convert to capacity percent of the battery total capacity, + * and multiplier is 100 too. + */ + delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap); + *cap = delta_cap + data->init_cap; + + return 0; +} + +static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val) +{ + int ret, vol; + + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol); + if (ret) + return ret; + + /* + * It is ADC values reading from registers which need to convert to + * corresponding voltage values. + */ + *val = sc27xx_fgu_adc_to_voltage(vol); + + return 0; +} + +static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val) +{ + int ret, cur; + + ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur); + if (ret) + return ret; + + /* + * It is ADC values reading from registers which need to convert to + * corresponding current values. + */ + *val = sc27xx_fgu_adc_to_current(cur - SC27XX_FGU_CUR_BASIC_ADC); + + return 0; +} + +static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val) +{ + int vol, cur, ret; + + ret = sc27xx_fgu_get_vbat_vol(data, &vol); + if (ret) + return ret; + + ret = sc27xx_fgu_get_current(data, &cur); + if (ret) + return ret; + + /* Return the battery OCV in micro volts. */ + *val = vol * 1000 - cur * data->internal_resist; + + return 0; +} + +static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp) +{ + return iio_read_channel_processed(data->channel, temp); +} + +static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health) +{ + int ret, vol; + + ret = sc27xx_fgu_get_vbat_vol(data, &vol); + if (ret) + return ret; + + if (vol > data->max_volt) + *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE; + else + *health = POWER_SUPPLY_HEALTH_GOOD; + + return 0; +} + +static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status) +{ + union power_supply_propval val; + struct power_supply *psy; + int i, ret = -EINVAL; + + for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) { + psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]); + if (!psy) + continue; + + ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS, + &val); + power_supply_put(psy); + if (ret) + return ret; + + *status = val.intval; + } + + return ret; +} + +static int sc27xx_fgu_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy); + int ret = 0; + int value; + + mutex_lock(&data->lock); + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + ret = sc27xx_fgu_get_status(data, &value); + if (ret) + goto error; + + val->intval = value; + break; + + case POWER_SUPPLY_PROP_HEALTH: + ret = sc27xx_fgu_get_health(data, &value); + if (ret) + goto error; + + val->intval = value; + break; + + case POWER_SUPPLY_PROP_PRESENT: + val->intval = data->bat_present; + break; + + case POWER_SUPPLY_PROP_TEMP: + ret = sc27xx_fgu_get_temp(data, &value); + if (ret) + goto error; + + val->intval = value; + break; + + case POWER_SUPPLY_PROP_TECHNOLOGY: + val->intval = POWER_SUPPLY_TECHNOLOGY_LION; + break; + + case POWER_SUPPLY_PROP_CAPACITY: + ret = sc27xx_fgu_get_capacity(data, &value); + if (ret) + goto error; + + val->intval = value; + break; + + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + ret = sc27xx_fgu_get_vbat_vol(data, &value); + if (ret) + goto error; + + val->intval = value * 1000; + break; + + case POWER_SUPPLY_PROP_VOLTAGE_OCV: + ret = sc27xx_fgu_get_vbat_ocv(data, &value); + if (ret) + goto error; + + val->intval = value; + break; + + case POWER_SUPPLY_PROP_CURRENT_NOW: + case POWER_SUPPLY_PROP_CURRENT_AVG: + ret = sc27xx_fgu_get_current(data, &value); + if (ret) + goto error; + + val->intval = value * 1000; + break; + + default: + ret = -EINVAL; + break; + } + +error: + mutex_unlock(&data->lock); + return ret; +} + +static void sc27xx_fgu_external_power_changed(struct power_supply *psy) +{ + struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy); + + power_supply_changed(data->battery); +} + +static enum power_supply_property sc27xx_fgu_props[] = { + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_HEALTH, + POWER_SUPPLY_PROP_PRESENT, + POWER_SUPPLY_PROP_TEMP, + POWER_SUPPLY_PROP_TECHNOLOGY, + POWER_SUPPLY_PROP_CAPACITY, + POWER_SUPPLY_PROP_VOLTAGE_NOW, + POWER_SUPPLY_PROP_VOLTAGE_OCV, + POWER_SUPPLY_PROP_CURRENT_NOW, + POWER_SUPPLY_PROP_CURRENT_AVG, +}; + +static const struct power_supply_desc sc27xx_fgu_desc = { + .name = "sc27xx-fgu", + .type = POWER_SUPPLY_TYPE_BATTERY, + .properties = sc27xx_fgu_props, + .num_properties = ARRAY_SIZE(sc27xx_fgu_props), + .get_property = sc27xx_fgu_get_property, + .external_power_changed = sc27xx_fgu_external_power_changed, +}; + +static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id) +{ + struct sc27xx_fgu_data *data = dev_id; + int state; + + mutex_lock(&data->lock); + + state = gpiod_get_value_cansleep(data->gpiod); + if (state < 0) { + dev_err(data->dev, "failed to get gpio state\n"); + mutex_unlock(&data->lock); + return IRQ_RETVAL(state); + } + + data->bat_present = !!state; + + mutex_unlock(&data->lock); + + power_supply_changed(data->battery); + return IRQ_HANDLED; +} + +static void sc27xx_fgu_disable(void *_data) +{ + struct sc27xx_fgu_data *data = _data; + + regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0); + regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0); +} + +static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity) +{ + /* + * Get current capacity (mAh) = battery total capacity (mAh) * + * current capacity percent (capacity / 100). + */ + int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100); + + /* + * Convert current capacity (mAh) to coulomb counter according to the + * formula: 1 mAh =3.6 coulomb. + */ + return DIV_ROUND_CLOSEST(cur_cap * 36, 10); +} + +static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data) +{ + struct power_supply_battery_info info = { }; + struct power_supply_battery_ocv_table *table; + int ret, i; + + ret = power_supply_get_battery_info(data->battery, &info); + if (ret) { + dev_err(data->dev, "failed to get battery information\n"); + return ret; + } + + data->total_cap = info.charge_full_design_uah / 1000; + data->max_volt = info.constant_charge_voltage_max_uv / 1000; + data->internal_resist = info.factory_internal_resistance_uohm / 1000; + + /* + * For SC27XX fuel gauge device, we only use one ocv-capacity + * table in normal temperature 20 Celsius. + */ + table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len); + if (!table) + return -EINVAL; + + data->cap_table = devm_kzalloc(data->dev, + data->table_len * sizeof(*table), + GFP_KERNEL); + if (!data->cap_table) { + power_supply_put_battery_info(data->battery, &info); + return -ENOMEM; + } + + for (i = 0; i < data->table_len; i++) { + data->cap_table[i].ocv = table[i].ocv / 1000; + data->cap_table[i].capacity = table[i].capacity; + } + + power_supply_put_battery_info(data->battery, &info); + + /* Enable the FGU module */ + ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, + SC27XX_FGU_EN, SC27XX_FGU_EN); + if (ret) { + dev_err(data->dev, "failed to enable fgu\n"); + return ret; + } + + /* Enable the FGU RTC clock to make it work */ + ret = regmap_update_bits(data->regmap, SC27XX_CLK_EN0, + SC27XX_FGU_RTC_EN, SC27XX_FGU_RTC_EN); + if (ret) { + dev_err(data->dev, "failed to enable fgu RTC clock\n"); + goto disable_fgu; + } + + /* + * Get the boot battery capacity when system powers on, which is used to + * initialize the coulomb counter. After that, we can read the coulomb + * counter to measure the battery capacity. + */ + ret = sc27xx_fgu_get_boot_capacity(data, &data->init_cap); + if (ret) { + dev_err(data->dev, "failed to get boot capacity\n"); + goto disable_clk; + } + + /* + * Convert battery capacity to the corresponding initial coulomb counter + * and set into coulomb counter registers. + */ + data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap); + ret = sc27xx_fgu_set_clbcnt(data, data->init_clbcnt); + if (ret) { + dev_err(data->dev, "failed to initialize coulomb counter\n"); + goto disable_clk; + } + + return 0; + +disable_clk: + regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0); +disable_fgu: + regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0); + + return ret; +} + +static int sc27xx_fgu_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct power_supply_config fgu_cfg = { }; + struct sc27xx_fgu_data *data; + int ret, irq; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!data->regmap) { + dev_err(&pdev->dev, "failed to get regmap\n"); + return -ENODEV; + } + + ret = device_property_read_u32(&pdev->dev, "reg", &data->base); + if (ret) { + dev_err(&pdev->dev, "failed to get fgu address\n"); + return ret; + } + + data->channel = devm_iio_channel_get(&pdev->dev, "bat-temp"); + if (IS_ERR(data->channel)) { + dev_err(&pdev->dev, "failed to get IIO channel\n"); + return PTR_ERR(data->channel); + } + + data->gpiod = devm_gpiod_get(&pdev->dev, "bat-detect", GPIOD_IN); + if (IS_ERR(data->gpiod)) { + dev_err(&pdev->dev, "failed to get battery detection GPIO\n"); + return PTR_ERR(data->gpiod); + } + + ret = gpiod_get_value_cansleep(data->gpiod); + if (ret < 0) { + dev_err(&pdev->dev, "failed to get gpio state\n"); + return ret; + } + + data->bat_present = !!ret; + mutex_init(&data->lock); + data->dev = &pdev->dev; + + fgu_cfg.drv_data = data; + fgu_cfg.of_node = np; + data->battery = devm_power_supply_register(&pdev->dev, &sc27xx_fgu_desc, + &fgu_cfg); + if (IS_ERR(data->battery)) { + dev_err(&pdev->dev, "failed to register power supply\n"); + return PTR_ERR(data->battery); + } + + ret = sc27xx_fgu_hw_init(data); + if (ret) { + dev_err(&pdev->dev, "failed to initialize fgu hardware\n"); + return ret; + } + + ret = devm_add_action(&pdev->dev, sc27xx_fgu_disable, data); + if (ret) { + sc27xx_fgu_disable(data); + dev_err(&pdev->dev, "failed to add fgu disable action\n"); + return ret; + } + + irq = gpiod_to_irq(data->gpiod); + if (irq < 0) { + dev_err(&pdev->dev, "failed to translate GPIO to IRQ\n"); + return irq; + } + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + sc27xx_fgu_bat_detection, + IRQF_ONESHOT | IRQF_TRIGGER_RISING | + IRQF_TRIGGER_FALLING, + pdev->name, data); + if (ret) { + dev_err(&pdev->dev, "failed to request IRQ\n"); + return ret; + } + + return 0; +} + +static const struct of_device_id sc27xx_fgu_of_match[] = { + { .compatible = "sprd,sc2731-fgu", }, + { } +}; + +static struct platform_driver sc27xx_fgu_driver = { + .probe = sc27xx_fgu_probe, + .driver = { + .name = "sc27xx-fgu", + .of_match_table = sc27xx_fgu_of_match, + } +}; + +module_platform_driver(sc27xx_fgu_driver); + +MODULE_DESCRIPTION("Spreadtrum SC27XX PMICs Fual Gauge Unit Driver"); +MODULE_LICENSE("GPL v2");