diff options
Diffstat (limited to 'drivers/iio/adc/qcom-spmi-vadc.c')
| -rw-r--r-- | drivers/iio/adc/qcom-spmi-vadc.c | 1016 |
1 files changed, 1016 insertions, 0 deletions
diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c new file mode 100644 index 000000000000..3211729bcb0b --- /dev/null +++ b/drivers/iio/adc/qcom-spmi-vadc.c @@ -0,0 +1,1016 @@ +/* + * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/bitops.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/iio/iio.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/log2.h> + +#include <dt-bindings/iio/qcom,spmi-vadc.h> + +/* VADC register and bit definitions */ +#define VADC_REVISION2 0x1 +#define VADC_REVISION2_SUPPORTED_VADC 1 + +#define VADC_PERPH_TYPE 0x4 +#define VADC_PERPH_TYPE_ADC 8 + +#define VADC_PERPH_SUBTYPE 0x5 +#define VADC_PERPH_SUBTYPE_VADC 1 + +#define VADC_STATUS1 0x8 +#define VADC_STATUS1_OP_MODE 4 +#define VADC_STATUS1_REQ_STS BIT(1) +#define VADC_STATUS1_EOC BIT(0) +#define VADC_STATUS1_REQ_STS_EOC_MASK 0x3 + +#define VADC_MODE_CTL 0x40 +#define VADC_OP_MODE_SHIFT 3 +#define VADC_OP_MODE_NORMAL 0 +#define VADC_AMUX_TRIM_EN BIT(1) +#define VADC_ADC_TRIM_EN BIT(0) + +#define VADC_EN_CTL1 0x46 +#define VADC_EN_CTL1_SET BIT(7) + +#define VADC_ADC_CH_SEL_CTL 0x48 + +#define VADC_ADC_DIG_PARAM 0x50 +#define VADC_ADC_DIG_DEC_RATIO_SEL_SHIFT 2 + +#define VADC_HW_SETTLE_DELAY 0x51 + +#define VADC_CONV_REQ 0x52 +#define VADC_CONV_REQ_SET BIT(7) + +#define VADC_FAST_AVG_CTL 0x5a +#define VADC_FAST_AVG_EN 0x5b +#define VADC_FAST_AVG_EN_SET BIT(7) + +#define VADC_ACCESS 0xd0 +#define VADC_ACCESS_DATA 0xa5 + +#define VADC_PERH_RESET_CTL3 0xda +#define VADC_FOLLOW_WARM_RB BIT(2) + +#define VADC_DATA 0x60 /* 16 bits */ + +#define VADC_CONV_TIME_MIN_US 2000 +#define VADC_CONV_TIME_MAX_US 2100 + +/* Min ADC code represents 0V */ +#define VADC_MIN_ADC_CODE 0x6000 +/* Max ADC code represents full-scale range of 1.8V */ +#define VADC_MAX_ADC_CODE 0xa800 + +#define VADC_ABSOLUTE_RANGE_UV 625000 +#define VADC_RATIOMETRIC_RANGE_UV 1800000 + +#define VADC_DEF_PRESCALING 0 /* 1:1 */ +#define VADC_DEF_DECIMATION 0 /* 512 */ +#define VADC_DEF_HW_SETTLE_TIME 0 /* 0 us */ +#define VADC_DEF_AVG_SAMPLES 0 /* 1 sample */ +#define VADC_DEF_CALIB_TYPE VADC_CALIB_ABSOLUTE + +#define VADC_DECIMATION_MIN 512 +#define VADC_DECIMATION_MAX 4096 + +#define VADC_HW_SETTLE_DELAY_MAX 10000 +#define VADC_AVG_SAMPLES_MAX 512 + +#define KELVINMIL_CELSIUSMIL 273150 + +#define VADC_CHAN_MIN VADC_USBIN +#define VADC_CHAN_MAX VADC_LR_MUX3_BUF_PU1_PU2_XO_THERM + +/* + * VADC_CALIB_ABSOLUTE: uses the 625mV and 1.25V as reference channels. + * VADC_CALIB_RATIOMETRIC: uses the reference voltage (1.8V) and GND for + * calibration. + */ +enum vadc_calibration { + VADC_CALIB_ABSOLUTE = 0, + VADC_CALIB_RATIOMETRIC +}; + +/** + * struct vadc_linear_graph - Represent ADC characteristics. + * @dy: numerator slope to calculate the gain. + * @dx: denominator slope to calculate the gain. + * @gnd: A/D word of the ground reference used for the channel. + * + * Each ADC device has different offset and gain parameters which are + * computed to calibrate the device. + */ +struct vadc_linear_graph { + s32 dy; + s32 dx; + s32 gnd; +}; + +/** + * struct vadc_prescale_ratio - Represent scaling ratio for ADC input. + * @num: the inverse numerator of the gain applied to the input channel. + * @den: the inverse denominator of the gain applied to the input channel. + */ +struct vadc_prescale_ratio { + u32 num; + u32 den; +}; + +/** + * struct vadc_channel_prop - VADC channel property. + * @channel: channel number, refer to the channel list. + * @calibration: calibration type. + * @decimation: sampling rate supported for the channel. + * @prescale: channel scaling performed on the input signal. + * @hw_settle_time: the time between AMUX being configured and the + * start of conversion. + * @avg_samples: ability to provide single result from the ADC + * that is an average of multiple measurements. + */ +struct vadc_channel_prop { + unsigned int channel; + enum vadc_calibration calibration; + unsigned int decimation; + unsigned int prescale; + unsigned int hw_settle_time; + unsigned int avg_samples; +}; + +/** + * struct vadc_priv - VADC private structure. + * @regmap: pointer to struct regmap. + * @dev: pointer to struct device. + * @base: base address for the ADC peripheral. + * @nchannels: number of VADC channels. + * @chan_props: array of VADC channel properties. + * @iio_chans: array of IIO channels specification. + * @are_ref_measured: are reference points measured. + * @poll_eoc: use polling instead of interrupt. + * @complete: VADC result notification after interrupt is received. + * @graph: store parameters for calibration. + * @lock: ADC lock for access to the peripheral. + */ +struct vadc_priv { + struct regmap *regmap; + struct device *dev; + u16 base; + unsigned int nchannels; + struct vadc_channel_prop *chan_props; + struct iio_chan_spec *iio_chans; + bool are_ref_measured; + bool poll_eoc; + struct completion complete; + struct vadc_linear_graph graph[2]; + struct mutex lock; +}; + +static const struct vadc_prescale_ratio vadc_prescale_ratios[] = { + {.num = 1, .den = 1}, + {.num = 1, .den = 3}, + {.num = 1, .den = 4}, + {.num = 1, .den = 6}, + {.num = 1, .den = 20}, + {.num = 1, .den = 8}, + {.num = 10, .den = 81}, + {.num = 1, .den = 10} +}; + +static int vadc_read(struct vadc_priv *vadc, u16 offset, u8 *data) +{ + return regmap_bulk_read(vadc->regmap, vadc->base + offset, data, 1); +} + +static int vadc_write(struct vadc_priv *vadc, u16 offset, u8 data) +{ + return regmap_write(vadc->regmap, vadc->base + offset, data); +} + +static int vadc_reset(struct vadc_priv *vadc) +{ + u8 data; + int ret; + + ret = vadc_write(vadc, VADC_ACCESS, VADC_ACCESS_DATA); + if (ret) + return ret; + + ret = vadc_read(vadc, VADC_PERH_RESET_CTL3, &data); + if (ret) + return ret; + + ret = vadc_write(vadc, VADC_ACCESS, VADC_ACCESS_DATA); + if (ret) + return ret; + + data |= VADC_FOLLOW_WARM_RB; + + return vadc_write(vadc, VADC_PERH_RESET_CTL3, data); +} + +static int vadc_set_state(struct vadc_priv *vadc, bool state) +{ + return vadc_write(vadc, VADC_EN_CTL1, state ? VADC_EN_CTL1_SET : 0); +} + +static void vadc_show_status(struct vadc_priv *vadc) +{ + u8 mode, sta1, chan, dig, en, req; + int ret; + + ret = vadc_read(vadc, VADC_MODE_CTL, &mode); + if (ret) + return; + + ret = vadc_read(vadc, VADC_ADC_DIG_PARAM, &dig); + if (ret) + return; + + ret = vadc_read(vadc, VADC_ADC_CH_SEL_CTL, &chan); + if (ret) + return; + + ret = vadc_read(vadc, VADC_CONV_REQ, &req); + if (ret) + return; + + ret = vadc_read(vadc, VADC_STATUS1, &sta1); + if (ret) + return; + + ret = vadc_read(vadc, VADC_EN_CTL1, &en); + if (ret) + return; + + dev_err(vadc->dev, + "mode:%02x en:%02x chan:%02x dig:%02x req:%02x sta1:%02x\n", + mode, en, chan, dig, req, sta1); +} + +static int vadc_configure(struct vadc_priv *vadc, + struct vadc_channel_prop *prop) +{ + u8 decimation, mode_ctrl; + int ret; + + /* Mode selection */ + mode_ctrl = (VADC_OP_MODE_NORMAL << VADC_OP_MODE_SHIFT) | + VADC_ADC_TRIM_EN | VADC_AMUX_TRIM_EN; + ret = vadc_write(vadc, VADC_MODE_CTL, mode_ctrl); + if (ret) + return ret; + + /* Channel selection */ + ret = vadc_write(vadc, VADC_ADC_CH_SEL_CTL, prop->channel); + if (ret) + return ret; + + /* Digital parameter setup */ + decimation = prop->decimation << VADC_ADC_DIG_DEC_RATIO_SEL_SHIFT; + ret = vadc_write(vadc, VADC_ADC_DIG_PARAM, decimation); + if (ret) + return ret; + + /* HW settle time delay */ + ret = vadc_write(vadc, VADC_HW_SETTLE_DELAY, prop->hw_settle_time); + if (ret) + return ret; + + ret = vadc_write(vadc, VADC_FAST_AVG_CTL, prop->avg_samples); + if (ret) + return ret; + + if (prop->avg_samples) + ret = vadc_write(vadc, VADC_FAST_AVG_EN, VADC_FAST_AVG_EN_SET); + else + ret = vadc_write(vadc, VADC_FAST_AVG_EN, 0); + + return ret; +} + +static int vadc_poll_wait_eoc(struct vadc_priv *vadc, unsigned int interval_us) +{ + unsigned int count, retry; + u8 sta1; + int ret; + + retry = interval_us / VADC_CONV_TIME_MIN_US; + + for (count = 0; count < retry; count++) { + ret = vadc_read(vadc, VADC_STATUS1, &sta1); + if (ret) + return ret; + + sta1 &= VADC_STATUS1_REQ_STS_EOC_MASK; + if (sta1 == VADC_STATUS1_EOC) + return 0; + + usleep_range(VADC_CONV_TIME_MIN_US, VADC_CONV_TIME_MAX_US); + } + + vadc_show_status(vadc); + + return -ETIMEDOUT; +} + +static int vadc_read_result(struct vadc_priv *vadc, u16 *data) +{ + int ret; + + ret = regmap_bulk_read(vadc->regmap, vadc->base + VADC_DATA, data, 2); + if (ret) + return ret; + + *data = clamp_t(u16, *data, VADC_MIN_ADC_CODE, VADC_MAX_ADC_CODE); + + return 0; +} + +static struct vadc_channel_prop *vadc_get_channel(struct vadc_priv *vadc, + unsigned int num) +{ + unsigned int i; + + for (i = 0; i < vadc->nchannels; i++) + if (vadc->chan_props[i].channel == num) + return &vadc->chan_props[i]; + + dev_dbg(vadc->dev, "no such channel %02x\n", num); + + return NULL; +} + +static int vadc_do_conversion(struct vadc_priv *vadc, + struct vadc_channel_prop *prop, u16 *data) +{ + unsigned int timeout; + int ret; + + mutex_lock(&vadc->lock); + + ret = vadc_configure(vadc, prop); + if (ret) + goto unlock; + + if (!vadc->poll_eoc) + reinit_completion(&vadc->complete); + + ret = vadc_set_state(vadc, true); + if (ret) + goto unlock; + + ret = vadc_write(vadc, VADC_CONV_REQ, VADC_CONV_REQ_SET); + if (ret) + goto err_disable; + + timeout = BIT(prop->avg_samples) * VADC_CONV_TIME_MIN_US * 2; + + if (vadc->poll_eoc) { + ret = vadc_poll_wait_eoc(vadc, timeout); + } else { + ret = wait_for_completion_timeout(&vadc->complete, timeout); + if (!ret) { + ret = -ETIMEDOUT; + goto err_disable; + } + + /* Double check conversion status */ + ret = vadc_poll_wait_eoc(vadc, VADC_CONV_TIME_MIN_US); + if (ret) + goto err_disable; + } + + ret = vadc_read_result(vadc, data); + +err_disable: + vadc_set_state(vadc, false); + if (ret) + dev_err(vadc->dev, "conversion failed\n"); +unlock: + mutex_unlock(&vadc->lock); + return ret; +} + +static int vadc_measure_ref_points(struct vadc_priv *vadc) +{ + struct vadc_channel_prop *prop; + u16 read_1, read_2; + int ret; + + vadc->graph[VADC_CALIB_RATIOMETRIC].dx = VADC_RATIOMETRIC_RANGE_UV; + vadc->graph[VADC_CALIB_ABSOLUTE].dx = VADC_ABSOLUTE_RANGE_UV; + + prop = vadc_get_channel(vadc, VADC_REF_1250MV); + ret = vadc_do_conversion(vadc, prop, &read_1); + if (ret) + goto err; + + /* Try with buffered 625mV channel first */ + prop = vadc_get_channel(vadc, VADC_SPARE1); + if (!prop) + prop = vadc_get_channel(vadc, VADC_REF_625MV); + + ret = vadc_do_conversion(vadc, prop, &read_2); + if (ret) + goto err; + + if (read_1 == read_2) { + ret = -EINVAL; + goto err; + } + + vadc->graph[VADC_CALIB_ABSOLUTE].dy = read_1 - read_2; + vadc->graph[VADC_CALIB_ABSOLUTE].gnd = read_2; + + /* Ratiometric calibration */ + prop = vadc_get_channel(vadc, VADC_VDD_VADC); + ret = vadc_do_conversion(vadc, prop, &read_1); + if (ret) + goto err; + + prop = vadc_get_channel(vadc, VADC_GND_REF); + ret = vadc_do_conversion(vadc, prop, &read_2); + if (ret) + goto err; + + if (read_1 == read_2) { + ret = -EINVAL; + goto err; + } + + vadc->graph[VADC_CALIB_RATIOMETRIC].dy = read_1 - read_2; + vadc->graph[VADC_CALIB_RATIOMETRIC].gnd = read_2; +err: + if (ret) + dev_err(vadc->dev, "measure reference points failed\n"); + + return ret; +} + +static s32 vadc_calibrate(struct vadc_priv *vadc, + const struct vadc_channel_prop *prop, u16 adc_code) +{ + const struct vadc_prescale_ratio *prescale; + s32 voltage; + + voltage = adc_code - vadc->graph[prop->calibration].gnd; + voltage *= vadc->graph[prop->calibration].dx; + voltage = voltage / vadc->graph[prop->calibration].dy; + + if (prop->calibration == VADC_CALIB_ABSOLUTE) + voltage += vadc->graph[prop->calibration].dx; + + if (voltage < 0) + voltage = 0; + + prescale = &vadc_prescale_ratios[prop->prescale]; + + voltage = voltage * prescale->den; + + return voltage / prescale->num; +} + +static int vadc_decimation_from_dt(u32 value) +{ + if (!is_power_of_2(value) || value < VADC_DECIMATION_MIN || + value > VADC_DECIMATION_MAX) + return -EINVAL; + + return __ffs64(value / VADC_DECIMATION_MIN); +} + +static int vadc_prescaling_from_dt(u32 num, u32 den) +{ + unsigned int pre; + + for (pre = 0; pre < ARRAY_SIZE(vadc_prescale_ratios); pre++) + if (vadc_prescale_ratios[pre].num == num && + vadc_prescale_ratios[pre].den == den) + break; + + if (pre == ARRAY_SIZE(vadc_prescale_ratios)) + return -EINVAL; + + return pre; +} + +static int vadc_hw_settle_time_from_dt(u32 value) +{ + if ((value <= 1000 && value % 100) || (value > 1000 && value % 2000)) + return -EINVAL; + + if (value <= 1000) + value /= 100; + else + value = value / 2000 + 10; + + return value; +} + +static int vadc_avg_samples_from_dt(u32 value) +{ + if (!is_power_of_2(value) || value > VADC_AVG_SAMPLES_MAX) + return -EINVAL; + + return __ffs64(value); +} + +static int vadc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, int *val2, + long mask) +{ + struct vadc_priv *vadc = iio_priv(indio_dev); + struct vadc_channel_prop *prop; + u16 adc_code; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_PROCESSED: + prop = &vadc->chan_props[chan->address]; + ret = vadc_do_conversion(vadc, prop, &adc_code); + if (ret) + break; + + *val = vadc_calibrate(vadc, prop, adc_code); + + /* 2mV/K, return milli Celsius */ + *val /= 2; + *val -= KELVINMIL_CELSIUSMIL; + return IIO_VAL_INT; + case IIO_CHAN_INFO_RAW: + prop = &vadc->chan_props[chan->address]; + ret = vadc_do_conversion(vadc, prop, &adc_code); + if (ret) + break; + + *val = vadc_calibrate(vadc, prop, adc_code); + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = 0; + *val2 = 1000; + return IIO_VAL_INT_PLUS_MICRO; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +static int vadc_of_xlate(struct iio_dev *indio_dev, + const struct of_phandle_args *iiospec) +{ + struct vadc_priv *vadc = iio_priv(indio_dev); + unsigned int i; + + for (i = 0; i < vadc->nchannels; i++) + if (vadc->iio_chans[i].channel == iiospec->args[0]) + return i; + + return -EINVAL; +} + +static const struct iio_info vadc_info = { + .read_raw = vadc_read_raw, + .of_xlate = vadc_of_xlate, + .driver_module = THIS_MODULE, +}; + +struct vadc_channels { + const char *datasheet_name; + unsigned int prescale_index; + enum iio_chan_type type; + long info_mask; +}; + +#define VADC_CHAN(_dname, _type, _mask, _pre) \ + [VADC_##_dname] = { \ + .datasheet_name = __stringify(_dname), \ + .prescale_index = _pre, \ + .type = _type, \ + .info_mask = _mask \ + }, \ + +#define VADC_CHAN_TEMP(_dname, _pre) \ + VADC_CHAN(_dname, IIO_TEMP, BIT(IIO_CHAN_INFO_PROCESSED), _pre) \ + +#define VADC_CHAN_VOLT(_dname, _pre) \ + VADC_CHAN(_dname, IIO_VOLTAGE, \ + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), \ + _pre) \ + +/* + * The array represents all possible ADC channels found in the supported PMICs. + * Every index in the array is equal to the channel number per datasheet. The + * gaps in the array should be treated as reserved channels. + */ +static const struct vadc_channels vadc_chans[] = { + VADC_CHAN_VOLT(USBIN, 4) + VADC_CHAN_VOLT(DCIN, 4) + VADC_CHAN_VOLT(VCHG_SNS, 3) + VADC_CHAN_VOLT(SPARE1_03, 1) + VADC_CHAN_VOLT(USB_ID_MV, 1) + VADC_CHAN_VOLT(VCOIN, 1) + VADC_CHAN_VOLT(VBAT_SNS, 1) + VADC_CHAN_VOLT(VSYS, 1) + VADC_CHAN_TEMP(DIE_TEMP, 0) + VADC_CHAN_VOLT(REF_625MV, 0) + VADC_CHAN_VOLT(REF_1250MV, 0) + VADC_CHAN_VOLT(CHG_TEMP, 0) + VADC_CHAN_VOLT(SPARE1, 0) + VADC_CHAN_VOLT(SPARE2, 0) + VADC_CHAN_VOLT(GND_REF, 0) + VADC_CHAN_VOLT(VDD_VADC, 0) + + VADC_CHAN_VOLT(P_MUX1_1_1, 0) + VADC_CHAN_VOLT(P_MUX2_1_1, 0) + VADC_CHAN_VOLT(P_MUX3_1_1, 0) + VADC_CHAN_VOLT(P_MUX4_1_1, 0) + VADC_CHAN_VOLT(P_MUX5_1_1, 0) + VADC_CHAN_VOLT(P_MUX6_1_1, 0) + VADC_CHAN_VOLT(P_MUX7_1_1, 0) + VADC_CHAN_VOLT(P_MUX8_1_1, 0) + VADC_CHAN_VOLT(P_MUX9_1_1, 0) + VADC_CHAN_VOLT(P_MUX10_1_1, 0) + VADC_CHAN_VOLT(P_MUX11_1_1, 0) + VADC_CHAN_VOLT(P_MUX12_1_1, 0) + VADC_CHAN_VOLT(P_MUX13_1_1, 0) + VADC_CHAN_VOLT(P_MUX14_1_1, 0) + VADC_CHAN_VOLT(P_MUX15_1_1, 0) + VADC_CHAN_VOLT(P_MUX16_1_1, 0) + + VADC_CHAN_VOLT(P_MUX1_1_3, 1) + VADC_CHAN_VOLT(P_MUX2_1_3, 1) + VADC_CHAN_VOLT(P_MUX3_1_3, 1) + VADC_CHAN_VOLT(P_MUX4_1_3, 1) + VADC_CHAN_VOLT(P_MUX5_1_3, 1) + VADC_CHAN_VOLT(P_MUX6_1_3, 1) + VADC_CHAN_VOLT(P_MUX7_1_3, 1) + VADC_CHAN_VOLT(P_MUX8_1_3, 1) + VADC_CHAN_VOLT(P_MUX9_1_3, 1) + VADC_CHAN_VOLT(P_MUX10_1_3, 1) + VADC_CHAN_VOLT(P_MUX11_1_3, 1) + VADC_CHAN_VOLT(P_MUX12_1_3, 1) + VADC_CHAN_VOLT(P_MUX13_1_3, 1) + VADC_CHAN_VOLT(P_MUX14_1_3, 1) + VADC_CHAN_VOLT(P_MUX15_1_3, 1) + VADC_CHAN_VOLT(P_MUX16_1_3, 1) + + VADC_CHAN_VOLT(LR_MUX1_BAT_THERM, 0) + VADC_CHAN_VOLT(LR_MUX2_BAT_ID, 0) + VADC_CHAN_VOLT(LR_MUX3_XO_THERM, 0) + VADC_CHAN_VOLT(LR_MUX4_AMUX_THM1, 0) + VADC_CHAN_VOLT(LR_MUX5_AMUX_THM2, 0) + VADC_CHAN_VOLT(LR_MUX6_AMUX_THM3, 0) + VADC_CHAN_VOLT(LR_MUX7_HW_ID, 0) + VADC_CHAN_VOLT(LR_MUX8_AMUX_THM4, 0) + VADC_CHAN_VOLT(LR_MUX9_AMUX_THM5, 0) + VADC_CHAN_VOLT(LR_MUX10_USB_ID, 0) + VADC_CHAN_VOLT(AMUX_PU1, 0) + VADC_CHAN_VOLT(AMUX_PU2, 0) + VADC_CHAN_VOLT(LR_MUX3_BUF_XO_THERM, 0) + + VADC_CHAN_VOLT(LR_MUX1_PU1_BAT_THERM, 0) + VADC_CHAN_VOLT(LR_MUX2_PU1_BAT_ID, 0) + VADC_CHAN_VOLT(LR_MUX3_PU1_XO_THERM, 0) + VADC_CHAN_VOLT(LR_MUX4_PU1_AMUX_THM1, 0) + VADC_CHAN_VOLT(LR_MUX5_PU1_AMUX_THM2, 0) + VADC_CHAN_VOLT(LR_MUX6_PU1_AMUX_THM3, 0) + VADC_CHAN_VOLT(LR_MUX7_PU1_AMUX_HW_ID, 0) + VADC_CHAN_VOLT(LR_MUX8_PU1_AMUX_THM4, 0) + VADC_CHAN_VOLT(LR_MUX9_PU1_AMUX_THM5, 0) + VADC_CHAN_VOLT(LR_MUX10_PU1_AMUX_USB_ID, 0) + VADC_CHAN_VOLT(LR_MUX3_BUF_PU1_XO_THERM, 0) + + VADC_CHAN_VOLT(LR_MUX1_PU2_BAT_THERM, 0) + VADC_CHAN_VOLT(LR_MUX2_PU2_BAT_ID, 0) + VADC_CHAN_VOLT(LR_MUX3_PU2_XO_THERM, 0) + VADC_CHAN_VOLT(LR_MUX4_PU2_AMUX_THM1, 0) + VADC_CHAN_VOLT(LR_MUX5_PU2_AMUX_THM2, 0) + VADC_CHAN_VOLT(LR_MUX6_PU2_AMUX_THM3, 0) + VADC_CHAN_VOLT(LR_MUX7_PU2_AMUX_HW_ID, 0) + VADC_CHAN_VOLT(LR_MUX8_PU2_AMUX_THM4, 0) + VADC_CHAN_VOLT(LR_MUX9_PU2_AMUX_THM5, 0) + VADC_CHAN_VOLT(LR_MUX10_PU2_AMUX_USB_ID, 0) + VADC_CHAN_VOLT(LR_MUX3_BUF_PU2_XO_THERM, 0) + + VADC_CHAN_VOLT(LR_MUX1_PU1_PU2_BAT_THERM, 0) + VADC_CHAN_VOLT(LR_MUX2_PU1_PU2_BAT_ID, 0) + VADC_CHAN_VOLT(LR_MUX3_PU1_PU2_XO_THERM, 0) + VADC_CHAN_VOLT(LR_MUX4_PU1_PU2_AMUX_THM1, 0) + VADC_CHAN_VOLT(LR_MUX5_PU1_PU2_AMUX_THM2, 0) + VADC_CHAN_VOLT(LR_MUX6_PU1_PU2_AMUX_THM3, 0) + VADC_CHAN_VOLT(LR_MUX7_PU1_PU2_AMUX_HW_ID, 0) + VADC_CHAN_VOLT(LR_MUX8_PU1_PU2_AMUX_THM4, 0) + VADC_CHAN_VOLT(LR_MUX9_PU1_PU2_AMUX_THM5, 0) + VADC_CHAN_VOLT(LR_MUX10_PU1_PU2_AMUX_USB_ID, 0) + VADC_CHAN_VOLT(LR_MUX3_BUF_PU1_PU2_XO_THERM, 0) +}; + +static int vadc_get_dt_channel_data(struct device *dev, + struct vadc_channel_prop *prop, + struct device_node *node) +{ + const char *name = node->name; + u32 chan, value, varr[2]; + int ret; + + ret = of_property_read_u32(node, "reg", &chan); + if (ret) { + dev_err(dev, "invalid channel number %s\n", name); + return ret; + } + + if (chan > VADC_CHAN_MAX || chan < VADC_CHAN_MIN) { + dev_err(dev, "%s invalid channel number %d\n", name, chan); + return -EINVAL; + } + + /* the channel has DT description */ + prop->channel = chan; + + ret = of_property_read_u32(node, "qcom,decimation", &value); + if (!ret) { + ret = vadc_decimation_from_dt(value); + if (ret < 0) { + dev_err(dev, "%02x invalid decimation %d\n", + chan, value); + return ret; + } + prop->decimation = ret; + } else { + prop->decimation = VADC_DEF_DECIMATION; + } + + ret = of_property_read_u32_array(node, "qcom,pre-scaling", varr, 2); + if (!ret) { + ret = vadc_prescaling_from_dt(varr[0], varr[1]); + if (ret < 0) { + dev_err(dev, "%02x invalid pre-scaling <%d %d>\n", + chan, varr[0], varr[1]); + return ret; + } + prop->prescale = ret; + } else { + prop->prescale = vadc_chans[prop->channel].prescale_index; + } + + ret = of_property_read_u32(node, "qcom,hw-settle-time", &value); + if (!ret) { + ret = vadc_hw_settle_time_from_dt(value); + if (ret < 0) { + dev_err(dev, "%02x invalid hw-settle-time %d us\n", + chan, value); + return ret; + } + prop->hw_settle_time = ret; + } else { + prop->hw_settle_time = VADC_DEF_HW_SETTLE_TIME; + } + + ret = of_property_read_u32(node, "qcom,avg-samples", &value); + if (!ret) { + ret = vadc_avg_samples_from_dt(value); + if (ret < 0) { + dev_err(dev, "%02x invalid avg-samples %d\n", + chan, value); + return ret; + } + prop->avg_samples = ret; + } else { + prop->avg_samples = VADC_DEF_AVG_SAMPLES; + } + + if (of_property_read_bool(node, "qcom,ratiometric")) + prop->calibration = VADC_CALIB_RATIOMETRIC; + else + prop->calibration = VADC_CALIB_ABSOLUTE; + + dev_dbg(dev, "%02x name %s\n", chan, name); + + return 0; +} + +static int vadc_get_dt_data(struct vadc_priv *vadc, struct device_node *node) +{ + const struct vadc_channels *vadc_chan; + struct iio_chan_spec *iio_chan; + struct vadc_channel_prop prop; + struct device_node *child; + unsigned int index = 0; + int ret; + + vadc->nchannels = of_get_available_child_count(node); + if (!vadc->nchannels) + return -EINVAL; + + vadc->iio_chans = devm_kcalloc(vadc->dev, vadc->nchannels, + sizeof(*vadc->iio_chans), GFP_KERNEL); + if (!vadc->iio_chans) + return -ENOMEM; + + vadc->chan_props = devm_kcalloc(vadc->dev, vadc->nchannels, + sizeof(*vadc->chan_props), GFP_KERNEL); + if (!vadc->chan_props) + return -ENOMEM; + + iio_chan = vadc->iio_chans; + + for_each_available_child_of_node(node, child) { + ret = vadc_get_dt_channel_data(vadc->dev, &prop, child); + if (ret) + return ret; + + vadc->chan_props[index] = prop; + + vadc_chan = &vadc_chans[prop.channel]; + + iio_chan->channel = prop.channel; + iio_chan->datasheet_name = vadc_chan->datasheet_name; + iio_chan->info_mask_separate = vadc_chan->info_mask; + iio_chan->type = vadc_chan->type; + iio_chan->indexed = 1; + iio_chan->address = index++; + + iio_chan++; + } + + /* These channels are mandatory, they are used as reference points */ + if (!vadc_get_channel(vadc, VADC_REF_1250MV)) { + dev_err(vadc->dev, "Please define 1.25V channel\n"); + return -ENODEV; + } + + if (!vadc_get_channel(vadc, VADC_REF_625MV)) { + dev_err(vadc->dev, "Please define 0.625V channel\n"); + return -ENODEV; + } + + if (!vadc_get_channel(vadc, VADC_VDD_VADC)) { + dev_err(vadc->dev, "Please define VDD channel\n"); + return -ENODEV; + } + + if (!vadc_get_channel(vadc, VADC_GND_REF)) { + dev_err(vadc->dev, "Please define GND channel\n"); + return -ENODEV; + } + + return 0; +} + +static irqreturn_t vadc_isr(int irq, void *dev_id) +{ + struct vadc_priv *vadc = dev_id; + + complete(&vadc->complete); + + return IRQ_HANDLED; +} + +static int vadc_check_revision(struct vadc_priv *vadc) +{ + u8 val; + int ret; + + ret = vadc_read(vadc, VADC_PERPH_TYPE, &val); + if (ret) + return ret; + + if (val < VADC_PERPH_TYPE_ADC) { + dev_err(vadc->dev, "%d is not ADC\n", val); + return -ENODEV; + } + + ret = vadc_read(vadc, VADC_PERPH_SUBTYPE, &val); + if (ret) + return ret; + + if (val < VADC_PERPH_SUBTYPE_VADC) { + dev_err(vadc->dev, "%d is not VADC\n", val); + return -ENODEV; + } + + ret = vadc_read(vadc, VADC_REVISION2, &val); + if (ret) + return ret; + + if (val < VADC_REVISION2_SUPPORTED_VADC) { + dev_err(vadc->dev, "revision %d not supported\n", val); + return -ENODEV; + } + + return 0; +} + +static int vadc_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct device *dev = &pdev->dev; + struct iio_dev *indio_dev; + struct vadc_priv *vadc; + struct regmap *regmap; + int ret, irq_eoc; + u32 reg; + + regmap = dev_get_regmap(dev->parent, NULL); + if (!regmap) + return -ENODEV; + + ret = of_property_read_u32(node, "reg", ®); + if (ret < 0) + return ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*vadc)); + if (!indio_dev) + return -ENOMEM; + + vadc = iio_priv(indio_dev); + vadc->regmap = regmap; + vadc->dev = dev; + vadc->base = reg; + vadc->are_ref_measured = false; + init_completion(&vadc->complete); + mutex_init(&vadc->lock); + + ret = vadc_check_revision(vadc); + if (ret) + return ret; + + ret = vadc_get_dt_data(vadc, node); + if (ret) + return ret; + + irq_eoc = platform_get_irq(pdev, 0); + if (irq_eoc < 0) { + if (irq_eoc == -EPROBE_DEFER || irq_eoc == -EINVAL) + return irq_eoc; + vadc->poll_eoc = true; + } else { + ret = devm_request_irq(dev, irq_eoc, vadc_isr, 0, + "spmi-vadc", vadc); + if (ret) + return ret; + } + + ret = vadc_reset(vadc); + if (ret) { + dev_err(dev, "reset failed\n"); + return ret; + } + + ret = vadc_measure_ref_points(vadc); + if (ret) + return ret; + + indio_dev->dev.parent = dev; + indio_dev->dev.of_node = node; + indio_dev->name = pdev->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &vadc_info; + indio_dev->channels = vadc->iio_chans; + indio_dev->num_channels = vadc->nchannels; + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct of_device_id vadc_match_table[] = { + { .compatible = "qcom,spmi-vadc" }, + { } +}; +MODULE_DEVICE_TABLE(of, vadc_match_table); + +static struct platform_driver vadc_driver = { + .driver = { + .name = "qcom-spmi-vadc", + .of_match_table = vadc_match_table, + }, + .probe = vadc_probe, +}; +module_platform_driver(vadc_driver); + +MODULE_ALIAS("platform:qcom-spmi-vadc"); +MODULE_DESCRIPTION("Qualcomm SPMI PMIC voltage ADC driver"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Stanimir Varbanov <svarbanov@mm-sol.com>"); +MODULE_AUTHOR("Ivan T. Ivanov <iivanov@mm-sol.com>"); |