diff options
Diffstat (limited to 'drivers/iio/adc/cpcap-adc.c')
| -rw-r--r-- | drivers/iio/adc/cpcap-adc.c | 1007 |
1 files changed, 1007 insertions, 0 deletions
diff --git a/drivers/iio/adc/cpcap-adc.c b/drivers/iio/adc/cpcap-adc.c new file mode 100644 index 000000000000..62d37f8725b8 --- /dev/null +++ b/drivers/iio/adc/cpcap-adc.c @@ -0,0 +1,1007 @@ +/* + * Copyright (C) 2017 Tony Lindgren <tony@atomide.com> + * + * Rewritten for Linux IIO framework with some code based on + * earlier driver found in the Motorola Linux kernel: + * + * Copyright (C) 2009-2010 Motorola, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 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/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/driver.h> +#include <linux/iio/iio.h> +#include <linux/iio/kfifo_buf.h> +#include <linux/mfd/motorola-cpcap.h> + +/* Register CPCAP_REG_ADCC1 bits */ +#define CPCAP_BIT_ADEN_AUTO_CLR BIT(15) /* Currently unused */ +#define CPCAP_BIT_CAL_MODE BIT(14) /* Set with BIT_RAND0 */ +#define CPCAP_BIT_ADC_CLK_SEL1 BIT(13) /* Currently unused */ +#define CPCAP_BIT_ADC_CLK_SEL0 BIT(12) /* Currently unused */ +#define CPCAP_BIT_ATOX BIT(11) +#define CPCAP_BIT_ATO3 BIT(10) +#define CPCAP_BIT_ATO2 BIT(9) +#define CPCAP_BIT_ATO1 BIT(8) +#define CPCAP_BIT_ATO0 BIT(7) +#define CPCAP_BIT_ADA2 BIT(6) +#define CPCAP_BIT_ADA1 BIT(5) +#define CPCAP_BIT_ADA0 BIT(4) +#define CPCAP_BIT_AD_SEL1 BIT(3) /* Set for bank1 */ +#define CPCAP_BIT_RAND1 BIT(2) /* Set for channel 16 & 17 */ +#define CPCAP_BIT_RAND0 BIT(1) /* Set with CAL_MODE */ +#define CPCAP_BIT_ADEN BIT(0) /* Currently unused */ + +/* Register CPCAP_REG_ADCC2 bits */ +#define CPCAP_BIT_CAL_FACTOR_ENABLE BIT(15) /* Currently unused */ +#define CPCAP_BIT_BATDETB_EN BIT(14) /* Currently unused */ +#define CPCAP_BIT_ADTRIG_ONESHOT BIT(13) /* Set for !TIMING_IMM */ +#define CPCAP_BIT_ASC BIT(12) /* Set for TIMING_IMM */ +#define CPCAP_BIT_ATOX_PS_FACTOR BIT(11) +#define CPCAP_BIT_ADC_PS_FACTOR1 BIT(10) +#define CPCAP_BIT_ADC_PS_FACTOR0 BIT(9) +#define CPCAP_BIT_AD4_SELECT BIT(8) /* Currently unused */ +#define CPCAP_BIT_ADC_BUSY BIT(7) /* Currently unused */ +#define CPCAP_BIT_THERMBIAS_EN BIT(6) /* Currently unused */ +#define CPCAP_BIT_ADTRIG_DIS BIT(5) /* Disable interrupt */ +#define CPCAP_BIT_LIADC BIT(4) /* Currently unused */ +#define CPCAP_BIT_TS_REFEN BIT(3) /* Currently unused */ +#define CPCAP_BIT_TS_M2 BIT(2) /* Currently unused */ +#define CPCAP_BIT_TS_M1 BIT(1) /* Currently unused */ +#define CPCAP_BIT_TS_M0 BIT(0) /* Currently unused */ + +#define CPCAP_MAX_TEMP_LVL 27 +#define CPCAP_FOUR_POINT_TWO_ADC 801 +#define ST_ADC_CAL_CHRGI_HIGH_THRESHOLD 530 +#define ST_ADC_CAL_CHRGI_LOW_THRESHOLD 494 +#define ST_ADC_CAL_BATTI_HIGH_THRESHOLD 530 +#define ST_ADC_CAL_BATTI_LOW_THRESHOLD 494 +#define ST_ADC_CALIBRATE_DIFF_THRESHOLD 3 + +#define CPCAP_ADC_MAX_RETRIES 5 /* Calibration and quirk */ + +/** + * struct cpcap_adc_ato - timing settings for cpcap adc + * + * Unfortunately no cpcap documentation available, please document when + * using these. + */ +struct cpcap_adc_ato { + unsigned short ato_in; + unsigned short atox_in; + unsigned short adc_ps_factor_in; + unsigned short atox_ps_factor_in; + unsigned short ato_out; + unsigned short atox_out; + unsigned short adc_ps_factor_out; + unsigned short atox_ps_factor_out; +}; + +/** + * struct cpcap-adc - cpcap adc device driver data + * @reg: cpcap regmap + * @dev: struct device + * @vendor: cpcap vendor + * @irq: interrupt + * @lock: mutex + * @ato: request timings + * @wq_data_avail: work queue + * @done: work done + */ +struct cpcap_adc { + struct regmap *reg; + struct device *dev; + u16 vendor; + int irq; + struct mutex lock; /* ADC register access lock */ + const struct cpcap_adc_ato *ato; + wait_queue_head_t wq_data_avail; + bool done; +}; + +/** + * enum cpcap_adc_channel - cpcap adc channels + */ +enum cpcap_adc_channel { + /* Bank0 channels */ + CPCAP_ADC_AD0_BATTDETB, /* Battery detection */ + CPCAP_ADC_BATTP, /* Battery voltage */ + CPCAP_ADC_VBUS, /* USB VBUS voltage */ + CPCAP_ADC_AD3, /* Battery temperature when charging */ + CPCAP_ADC_BPLUS_AD4, /* Another battery or system voltage */ + CPCAP_ADC_CHG_ISENSE, /* Calibrated charge current */ + CPCAP_ADC_BATTI, /* Calibrated system current */ + CPCAP_ADC_USB_ID, /* USB OTG ID, unused on droid 4? */ + + /* Bank1 channels */ + CPCAP_ADC_AD8, /* Seems unused */ + CPCAP_ADC_AD9, /* Seems unused */ + CPCAP_ADC_LICELL, /* Maybe system voltage? Always 3V */ + CPCAP_ADC_HV_BATTP, /* Another battery detection? */ + CPCAP_ADC_TSX1_AD12, /* Seems unused, for touchscreen? */ + CPCAP_ADC_TSX2_AD13, /* Seems unused, for touchscreen? */ + CPCAP_ADC_TSY1_AD14, /* Seems unused, for touchscreen? */ + CPCAP_ADC_TSY2_AD15, /* Seems unused, for touchscreen? */ + + /* Remuxed channels using bank0 entries */ + CPCAP_ADC_BATTP_PI16, /* Alternative mux mode for BATTP */ + CPCAP_ADC_BATTI_PI17, /* Alternative mux mode for BATTI */ + + CPCAP_ADC_CHANNEL_NUM, +}; + +/** + * enum cpcap_adc_timing - cpcap adc timing options + * + * CPCAP_ADC_TIMING_IMM seems to be immediate with no timings. + * Please document when using. + */ +enum cpcap_adc_timing { + CPCAP_ADC_TIMING_IMM, + CPCAP_ADC_TIMING_IN, + CPCAP_ADC_TIMING_OUT, +}; + +/** + * struct cpcap_adc_phasing_tbl - cpcap phasing table + * @offset: offset in the phasing table + * @multiplier: multiplier in the phasing table + * @divider: divider in the phasing table + * @min: minimum value + * @max: maximum value + */ +struct cpcap_adc_phasing_tbl { + short offset; + unsigned short multiplier; + unsigned short divider; + short min; + short max; +}; + +/** + * struct cpcap_adc_conversion_tbl - cpcap conversion table + * @conv_type: conversion type + * @align_offset: align offset + * @conv_offset: conversion offset + * @cal_offset: calibration offset + * @multiplier: conversion multiplier + * @divider: conversion divider + */ +struct cpcap_adc_conversion_tbl { + enum iio_chan_info_enum conv_type; + int align_offset; + int conv_offset; + int cal_offset; + int multiplier; + int divider; +}; + +/** + * struct cpcap_adc_request - cpcap adc request + * @channel: request channel + * @phase_tbl: channel phasing table + * @conv_tbl: channel conversion table + * @bank_index: channel index within the bank + * @timing: timing settings + * @result: result + */ +struct cpcap_adc_request { + int channel; + const struct cpcap_adc_phasing_tbl *phase_tbl; + const struct cpcap_adc_conversion_tbl *conv_tbl; + int bank_index; + enum cpcap_adc_timing timing; + int result; +}; + +/* Phasing table for channels. Note that channels 16 & 17 use BATTP and BATTI */ +static const struct cpcap_adc_phasing_tbl bank_phasing[] = { + /* Bank0 */ + [CPCAP_ADC_AD0_BATTDETB] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_BATTP] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_VBUS] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_AD3] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_BPLUS_AD4] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_CHG_ISENSE] = {0, 0x80, 0x80, -512, 511}, + [CPCAP_ADC_BATTI] = {0, 0x80, 0x80, -512, 511}, + [CPCAP_ADC_USB_ID] = {0, 0x80, 0x80, 0, 1023}, + + /* Bank1 */ + [CPCAP_ADC_AD8] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_AD9] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_LICELL] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_HV_BATTP] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_TSX1_AD12] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_TSX2_AD13] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_TSY1_AD14] = {0, 0x80, 0x80, 0, 1023}, + [CPCAP_ADC_TSY2_AD15] = {0, 0x80, 0x80, 0, 1023}, +}; + +/* + * Conversion table for channels. Updated during init based on calibration. + * Here too channels 16 & 17 use BATTP and BATTI. + */ +static struct cpcap_adc_conversion_tbl bank_conversion[] = { + /* Bank0 */ + [CPCAP_ADC_AD0_BATTDETB] = { + IIO_CHAN_INFO_PROCESSED, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_BATTP] = { + IIO_CHAN_INFO_PROCESSED, 0, 2400, 0, 2300, 1023, + }, + [CPCAP_ADC_VBUS] = { + IIO_CHAN_INFO_PROCESSED, 0, 0, 0, 10000, 1023, + }, + [CPCAP_ADC_AD3] = { + IIO_CHAN_INFO_PROCESSED, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_BPLUS_AD4] = { + IIO_CHAN_INFO_PROCESSED, 0, 2400, 0, 2300, 1023, + }, + [CPCAP_ADC_CHG_ISENSE] = { + IIO_CHAN_INFO_PROCESSED, -512, 2, 0, 5000, 1023, + }, + [CPCAP_ADC_BATTI] = { + IIO_CHAN_INFO_PROCESSED, -512, 2, 0, 5000, 1023, + }, + [CPCAP_ADC_USB_ID] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, + + /* Bank1 */ + [CPCAP_ADC_AD8] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_AD9] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_LICELL] = { + IIO_CHAN_INFO_PROCESSED, 0, 0, 0, 3400, 1023, + }, + [CPCAP_ADC_HV_BATTP] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_TSX1_AD12] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_TSX2_AD13] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_TSY1_AD14] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, + [CPCAP_ADC_TSY2_AD15] = { + IIO_CHAN_INFO_RAW, 0, 0, 0, 1, 1, + }, +}; + +/* + * Temperature lookup table of register values to milliCelcius. + * REVISIT: Check the duplicate 0x3ff entry in a freezer + */ +static const int temp_map[CPCAP_MAX_TEMP_LVL][2] = { + { 0x03ff, -40000 }, + { 0x03ff, -35000 }, + { 0x03ef, -30000 }, + { 0x03b2, -25000 }, + { 0x036c, -20000 }, + { 0x0320, -15000 }, + { 0x02d0, -10000 }, + { 0x027f, -5000 }, + { 0x022f, 0 }, + { 0x01e4, 5000 }, + { 0x019f, 10000 }, + { 0x0161, 15000 }, + { 0x012b, 20000 }, + { 0x00fc, 25000 }, + { 0x00d4, 30000 }, + { 0x00b2, 35000 }, + { 0x0095, 40000 }, + { 0x007d, 45000 }, + { 0x0069, 50000 }, + { 0x0059, 55000 }, + { 0x004b, 60000 }, + { 0x003f, 65000 }, + { 0x0036, 70000 }, + { 0x002e, 75000 }, + { 0x0027, 80000 }, + { 0x0022, 85000 }, + { 0x001d, 90000 }, +}; + +#define CPCAP_CHAN(_type, _index, _address, _datasheet_name) { \ + .type = (_type), \ + .address = (_address), \ + .indexed = 1, \ + .channel = (_index), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_PROCESSED), \ + .scan_index = (_index), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 10, \ + .storagebits = 16, \ + .endianness = IIO_CPU, \ + }, \ + .datasheet_name = (_datasheet_name), \ +} + +/* + * The datasheet names are from Motorola mapphone Linux kernel except + * for the last two which might be uncalibrated charge voltage and + * current. + */ +static const struct iio_chan_spec cpcap_adc_channels[] = { + /* Bank0 */ + CPCAP_CHAN(IIO_TEMP, 0, CPCAP_REG_ADCD0, "battdetb"), + CPCAP_CHAN(IIO_VOLTAGE, 1, CPCAP_REG_ADCD1, "battp"), + CPCAP_CHAN(IIO_VOLTAGE, 2, CPCAP_REG_ADCD2, "vbus"), + CPCAP_CHAN(IIO_TEMP, 3, CPCAP_REG_ADCD3, "ad3"), + CPCAP_CHAN(IIO_VOLTAGE, 4, CPCAP_REG_ADCD4, "ad4"), + CPCAP_CHAN(IIO_CURRENT, 5, CPCAP_REG_ADCD5, "chg_isense"), + CPCAP_CHAN(IIO_CURRENT, 6, CPCAP_REG_ADCD6, "batti"), + CPCAP_CHAN(IIO_VOLTAGE, 7, CPCAP_REG_ADCD7, "usb_id"), + + /* Bank1 */ + CPCAP_CHAN(IIO_CURRENT, 8, CPCAP_REG_ADCD0, "ad8"), + CPCAP_CHAN(IIO_VOLTAGE, 9, CPCAP_REG_ADCD1, "ad9"), + CPCAP_CHAN(IIO_VOLTAGE, 10, CPCAP_REG_ADCD2, "licell"), + CPCAP_CHAN(IIO_VOLTAGE, 11, CPCAP_REG_ADCD3, "hv_battp"), + CPCAP_CHAN(IIO_VOLTAGE, 12, CPCAP_REG_ADCD4, "tsx1_ad12"), + CPCAP_CHAN(IIO_VOLTAGE, 13, CPCAP_REG_ADCD5, "tsx2_ad13"), + CPCAP_CHAN(IIO_VOLTAGE, 14, CPCAP_REG_ADCD6, "tsy1_ad14"), + CPCAP_CHAN(IIO_VOLTAGE, 15, CPCAP_REG_ADCD7, "tsy2_ad15"), + + /* There are two registers with multiplexed functionality */ + CPCAP_CHAN(IIO_VOLTAGE, 16, CPCAP_REG_ADCD0, "chg_vsense"), + CPCAP_CHAN(IIO_CURRENT, 17, CPCAP_REG_ADCD1, "batti2"), +}; + +static irqreturn_t cpcap_adc_irq_thread(int irq, void *data) +{ + struct iio_dev *indio_dev = data; + struct cpcap_adc *ddata = iio_priv(indio_dev); + int error; + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ADTRIG_DIS, + CPCAP_BIT_ADTRIG_DIS); + if (error) + return IRQ_NONE; + + ddata->done = true; + wake_up_interruptible(&ddata->wq_data_avail); + + return IRQ_HANDLED; +} + +/* ADC calibration functions */ +static void cpcap_adc_setup_calibrate(struct cpcap_adc *ddata, + enum cpcap_adc_channel chan) +{ + unsigned int value = 0; + unsigned long timeout = jiffies + msecs_to_jiffies(3000); + int error; + + if ((chan != CPCAP_ADC_CHG_ISENSE) && + (chan != CPCAP_ADC_BATTI)) + return; + + value |= CPCAP_BIT_CAL_MODE | CPCAP_BIT_RAND0; + value |= ((chan << 4) & + (CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 | CPCAP_BIT_ADA0)); + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1, + CPCAP_BIT_CAL_MODE | CPCAP_BIT_ATOX | + CPCAP_BIT_ATO3 | CPCAP_BIT_ATO2 | + CPCAP_BIT_ATO1 | CPCAP_BIT_ATO0 | + CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 | + CPCAP_BIT_ADA0 | CPCAP_BIT_AD_SEL1 | + CPCAP_BIT_RAND1 | CPCAP_BIT_RAND0, + value); + if (error) + return; + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ATOX_PS_FACTOR | + CPCAP_BIT_ADC_PS_FACTOR1 | + CPCAP_BIT_ADC_PS_FACTOR0, + 0); + if (error) + return; + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ADTRIG_DIS, + CPCAP_BIT_ADTRIG_DIS); + if (error) + return; + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ASC, + CPCAP_BIT_ASC); + if (error) + return; + + do { + schedule_timeout_uninterruptible(1); + error = regmap_read(ddata->reg, CPCAP_REG_ADCC2, &value); + if (error) + return; + } while ((value & CPCAP_BIT_ASC) && time_before(jiffies, timeout)); + + if (value & CPCAP_BIT_ASC) + dev_err(ddata->dev, + "Timeout waiting for calibration to complete\n"); + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1, + CPCAP_BIT_CAL_MODE, 0); + if (error) + return; +} + +static int cpcap_adc_calibrate_one(struct cpcap_adc *ddata, + int channel, + u16 calibration_register, + int lower_threshold, + int upper_threshold) +{ + unsigned int calibration_data[2]; + unsigned short cal_data_diff; + int i, error; + + for (i = 0; i < CPCAP_ADC_MAX_RETRIES; i++) { + calibration_data[0] = 0; + calibration_data[1] = 0; + cal_data_diff = 0; + cpcap_adc_setup_calibrate(ddata, channel); + error = regmap_read(ddata->reg, calibration_register, + &calibration_data[0]); + if (error) + return error; + cpcap_adc_setup_calibrate(ddata, channel); + error = regmap_read(ddata->reg, calibration_register, + &calibration_data[1]); + if (error) + return error; + + if (calibration_data[0] > calibration_data[1]) + cal_data_diff = + calibration_data[0] - calibration_data[1]; + else + cal_data_diff = + calibration_data[1] - calibration_data[0]; + + if (((calibration_data[1] >= lower_threshold) && + (calibration_data[1] <= upper_threshold) && + (cal_data_diff <= ST_ADC_CALIBRATE_DIFF_THRESHOLD)) || + (ddata->vendor == CPCAP_VENDOR_TI)) { + bank_conversion[channel].cal_offset = + ((short)calibration_data[1] * -1) + 512; + dev_dbg(ddata->dev, "ch%i calibration complete: %i\n", + channel, bank_conversion[channel].cal_offset); + break; + } + usleep_range(5000, 10000); + } + + return 0; +} + +static int cpcap_adc_calibrate(struct cpcap_adc *ddata) +{ + int error; + + error = cpcap_adc_calibrate_one(ddata, CPCAP_ADC_CHG_ISENSE, + CPCAP_REG_ADCAL1, + ST_ADC_CAL_CHRGI_LOW_THRESHOLD, + ST_ADC_CAL_CHRGI_HIGH_THRESHOLD); + if (error) + return error; + + error = cpcap_adc_calibrate_one(ddata, CPCAP_ADC_BATTI, + CPCAP_REG_ADCAL2, + ST_ADC_CAL_BATTI_LOW_THRESHOLD, + ST_ADC_CAL_BATTI_HIGH_THRESHOLD); + if (error) + return error; + + return 0; +} + +/* ADC setup, read and scale functions */ +static void cpcap_adc_setup_bank(struct cpcap_adc *ddata, + struct cpcap_adc_request *req) +{ + const struct cpcap_adc_ato *ato = ddata->ato; + unsigned short value1 = 0; + unsigned short value2 = 0; + int error; + + if (!ato) + return; + + switch (req->channel) { + case CPCAP_ADC_AD8 ... CPCAP_ADC_TSY2_AD15: + value1 |= CPCAP_BIT_AD_SEL1; + break; + case CPCAP_ADC_BATTP_PI16 ... CPCAP_ADC_BATTI_PI17: + value1 |= CPCAP_BIT_RAND1; + default: + break; + } + + switch (req->timing) { + case CPCAP_ADC_TIMING_IN: + value1 |= ato->ato_in; + value1 |= ato->atox_in; + value2 |= ato->adc_ps_factor_in; + value2 |= ato->atox_ps_factor_in; + break; + case CPCAP_ADC_TIMING_OUT: + value1 |= ato->ato_out; + value1 |= ato->atox_out; + value2 |= ato->adc_ps_factor_out; + value2 |= ato->atox_ps_factor_out; + break; + + case CPCAP_ADC_TIMING_IMM: + default: + break; + } + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1, + CPCAP_BIT_CAL_MODE | CPCAP_BIT_ATOX | + CPCAP_BIT_ATO3 | CPCAP_BIT_ATO2 | + CPCAP_BIT_ATO1 | CPCAP_BIT_ATO0 | + CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 | + CPCAP_BIT_ADA0 | CPCAP_BIT_AD_SEL1 | + CPCAP_BIT_RAND1 | CPCAP_BIT_RAND0, + value1); + if (error) + return; + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ATOX_PS_FACTOR | + CPCAP_BIT_ADC_PS_FACTOR1 | + CPCAP_BIT_ADC_PS_FACTOR0, + value2); + if (error) + return; + + if (req->timing == CPCAP_ADC_TIMING_IMM) { + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ADTRIG_DIS, + CPCAP_BIT_ADTRIG_DIS); + if (error) + return; + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ASC, + CPCAP_BIT_ASC); + if (error) + return; + } else { + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ADTRIG_ONESHOT, + CPCAP_BIT_ADTRIG_ONESHOT); + if (error) + return; + + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ADTRIG_DIS, 0); + if (error) + return; + } +} + +/* + * Occasionally the ADC does not seem to start and there will be no + * interrupt. Let's re-init interrupt to prevent the ADC from hanging + * for the next request. It is unclear why this happens, but the next + * request will usually work after doing this. + */ +static void cpcap_adc_quirk_reset_lost_irq(struct cpcap_adc *ddata) +{ + int error; + + dev_info(ddata->dev, "lost ADC irq, attempting to reinit\n"); + disable_irq(ddata->irq); + error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2, + CPCAP_BIT_ADTRIG_DIS, + CPCAP_BIT_ADTRIG_DIS); + if (error) + dev_warn(ddata->dev, "%s reset failed: %i\n", + __func__, error); + enable_irq(ddata->irq); +} + +static int cpcap_adc_start_bank(struct cpcap_adc *ddata, + struct cpcap_adc_request *req) +{ + int i, error; + + req->timing = CPCAP_ADC_TIMING_IMM; + ddata->done = false; + + for (i = 0; i < CPCAP_ADC_MAX_RETRIES; i++) { + cpcap_adc_setup_bank(ddata, req); + error = wait_event_interruptible_timeout(ddata->wq_data_avail, + ddata->done, + msecs_to_jiffies(50)); + if (error > 0) + return 0; + + if (error == 0) { + cpcap_adc_quirk_reset_lost_irq(ddata); + error = -ETIMEDOUT; + continue; + } + + if (error < 0) + return error; + } + + return error; +} + +static void cpcap_adc_phase(struct cpcap_adc_request *req) +{ + const struct cpcap_adc_conversion_tbl *conv_tbl = req->conv_tbl; + const struct cpcap_adc_phasing_tbl *phase_tbl = req->phase_tbl; + int index = req->channel; + + /* Remuxed channels 16 and 17 use BATTP and BATTI entries */ + switch (req->channel) { + case CPCAP_ADC_BATTP: + case CPCAP_ADC_BATTP_PI16: + index = req->bank_index; + req->result -= phase_tbl[index].offset; + req->result -= CPCAP_FOUR_POINT_TWO_ADC; + req->result *= phase_tbl[index].multiplier; + if (phase_tbl[index].divider == 0) + return; + req->result /= phase_tbl[index].divider; + req->result += CPCAP_FOUR_POINT_TWO_ADC; + break; + case CPCAP_ADC_BATTI_PI17: + index = req->bank_index; + /* fallthrough */ + default: + req->result += conv_tbl[index].cal_offset; + req->result += conv_tbl[index].align_offset; + req->result *= phase_tbl[index].multiplier; + if (phase_tbl[index].divider == 0) + return; + req->result /= phase_tbl[index].divider; + req->result += phase_tbl[index].offset; + break; + } + + if (req->result < phase_tbl[index].min) + req->result = phase_tbl[index].min; + else if (req->result > phase_tbl[index].max) + req->result = phase_tbl[index].max; +} + +/* Looks up temperatures in a table and calculates averages if needed */ +static int cpcap_adc_table_to_millicelcius(unsigned short value) +{ + int i, result = 0, alpha; + + if (value <= temp_map[CPCAP_MAX_TEMP_LVL - 1][0]) + return temp_map[CPCAP_MAX_TEMP_LVL - 1][1]; + + if (value >= temp_map[0][0]) + return temp_map[0][1]; + + for (i = 0; i < CPCAP_MAX_TEMP_LVL - 1; i++) { + if ((value <= temp_map[i][0]) && + (value >= temp_map[i + 1][0])) { + if (value == temp_map[i][0]) { + result = temp_map[i][1]; + } else if (value == temp_map[i + 1][0]) { + result = temp_map[i + 1][1]; + } else { + alpha = ((value - temp_map[i][0]) * 1000) / + (temp_map[i + 1][0] - temp_map[i][0]); + + result = temp_map[i][1] + + ((alpha * (temp_map[i + 1][1] - + temp_map[i][1])) / 1000); + } + break; + } + } + + return result; +} + +static void cpcap_adc_convert(struct cpcap_adc_request *req) +{ + const struct cpcap_adc_conversion_tbl *conv_tbl = req->conv_tbl; + int index = req->channel; + + /* Remuxed channels 16 and 17 use BATTP and BATTI entries */ + switch (req->channel) { + case CPCAP_ADC_BATTP_PI16: + index = CPCAP_ADC_BATTP; + break; + case CPCAP_ADC_BATTI_PI17: + index = CPCAP_ADC_BATTI; + break; + default: + break; + } + + /* No conversion for raw channels */ + if (conv_tbl[index].conv_type == IIO_CHAN_INFO_RAW) + return; + + /* Temperatures use a lookup table instead of conversion table */ + if ((req->channel == CPCAP_ADC_AD0_BATTDETB) || + (req->channel == CPCAP_ADC_AD3)) { + req->result = + cpcap_adc_table_to_millicelcius(req->result); + + return; + } + + /* All processed channels use a conversion table */ + req->result *= conv_tbl[index].multiplier; + if (conv_tbl[index].divider == 0) + return; + req->result /= conv_tbl[index].divider; + req->result += conv_tbl[index].conv_offset; +} + +/* + * REVISIT: Check if timed sampling can use multiple channels at the + * same time. If not, replace channel_mask with just channel. + */ +static int cpcap_adc_read_bank_scaled(struct cpcap_adc *ddata, + struct cpcap_adc_request *req) +{ + int calibration_data, error, addr; + + if (ddata->vendor == CPCAP_VENDOR_TI) { + error = regmap_read(ddata->reg, CPCAP_REG_ADCAL1, + &calibration_data); + if (error) + return error; + bank_conversion[CPCAP_ADC_CHG_ISENSE].cal_offset = + ((short)calibration_data * -1) + 512; + + error = regmap_read(ddata->reg, CPCAP_REG_ADCAL2, + &calibration_data); + if (error) + return error; + bank_conversion[CPCAP_ADC_BATTI].cal_offset = + ((short)calibration_data * -1) + 512; + } + + addr = CPCAP_REG_ADCD0 + req->bank_index * 4; + + error = regmap_read(ddata->reg, addr, &req->result); + if (error) + return error; + + req->result &= 0x3ff; + cpcap_adc_phase(req); + cpcap_adc_convert(req); + + return 0; +} + +static int cpcap_adc_init_request(struct cpcap_adc_request *req, + int channel) +{ + req->channel = channel; + req->phase_tbl = bank_phasing; + req->conv_tbl = bank_conversion; + + switch (channel) { + case CPCAP_ADC_AD0_BATTDETB ... CPCAP_ADC_USB_ID: + req->bank_index = channel; + break; + case CPCAP_ADC_AD8 ... CPCAP_ADC_TSY2_AD15: + req->bank_index = channel - 8; + break; + case CPCAP_ADC_BATTP_PI16: + req->bank_index = CPCAP_ADC_BATTP; + break; + case CPCAP_ADC_BATTI_PI17: + req->bank_index = CPCAP_ADC_BATTI; + break; + default: + return -EINVAL; + } + + return 0; +} + +static int cpcap_adc_read(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct cpcap_adc *ddata = iio_priv(indio_dev); + struct cpcap_adc_request req; + int error; + + error = cpcap_adc_init_request(&req, chan->channel); + if (error) + return error; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&ddata->lock); + error = cpcap_adc_start_bank(ddata, &req); + if (error) + goto err_unlock; + error = regmap_read(ddata->reg, chan->address, val); + if (error) + goto err_unlock; + mutex_unlock(&ddata->lock); + break; + case IIO_CHAN_INFO_PROCESSED: + mutex_lock(&ddata->lock); + error = cpcap_adc_start_bank(ddata, &req); + if (error) + goto err_unlock; + error = cpcap_adc_read_bank_scaled(ddata, &req); + if (error) + goto err_unlock; + mutex_unlock(&ddata->lock); + *val = req.result; + break; + default: + return -EINVAL; + } + + return IIO_VAL_INT; + +err_unlock: + mutex_unlock(&ddata->lock); + dev_err(ddata->dev, "error reading ADC: %i\n", error); + + return error; +} + +static const struct iio_info cpcap_adc_info = { + .read_raw = &cpcap_adc_read, + .driver_module = THIS_MODULE, +}; + +/* + * Configuration for Motorola mapphone series such as droid 4. + * Copied from the Motorola mapphone kernel tree. + */ +static const struct cpcap_adc_ato mapphone_adc = { + .ato_in = 0x0480, + .atox_in = 0, + .adc_ps_factor_in = 0x0200, + .atox_ps_factor_in = 0, + .ato_out = 0, + .atox_out = 0, + .adc_ps_factor_out = 0, + .atox_ps_factor_out = 0, +}; + +static const struct of_device_id cpcap_adc_id_table[] = { + { + .compatible = "motorola,cpcap-adc", + }, + { + .compatible = "motorola,mapphone-cpcap-adc", + .data = &mapphone_adc, + }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, cpcap_adc_id_table); + +static int cpcap_adc_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct cpcap_adc *ddata; + struct iio_dev *indio_dev; + int error; + + match = of_match_device(of_match_ptr(cpcap_adc_id_table), + &pdev->dev); + if (!match) + return -EINVAL; + + if (!match->data) { + dev_err(&pdev->dev, "no configuration data found\n"); + + return -ENODEV; + } + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*ddata)); + if (!indio_dev) { + dev_err(&pdev->dev, "failed to allocate iio device\n"); + + return -ENOMEM; + } + ddata = iio_priv(indio_dev); + ddata->ato = match->data; + ddata->dev = &pdev->dev; + + mutex_init(&ddata->lock); + init_waitqueue_head(&ddata->wq_data_avail); + + indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE; + indio_dev->dev.parent = &pdev->dev; + indio_dev->dev.of_node = pdev->dev.of_node; + indio_dev->channels = cpcap_adc_channels; + indio_dev->num_channels = ARRAY_SIZE(cpcap_adc_channels); + indio_dev->name = dev_name(&pdev->dev); + indio_dev->info = &cpcap_adc_info; + + ddata->reg = dev_get_regmap(pdev->dev.parent, NULL); + if (!ddata->reg) + return -ENODEV; + + error = cpcap_get_vendor(ddata->dev, ddata->reg, &ddata->vendor); + if (error) + return error; + + platform_set_drvdata(pdev, indio_dev); + + ddata->irq = platform_get_irq_byname(pdev, "adcdone"); + if (!ddata->irq) + return -ENODEV; + + error = devm_request_threaded_irq(&pdev->dev, ddata->irq, NULL, + cpcap_adc_irq_thread, + IRQF_TRIGGER_NONE, + "cpcap-adc", indio_dev); + if (error) { + dev_err(&pdev->dev, "could not get irq: %i\n", + error); + + return error; + } + + error = cpcap_adc_calibrate(ddata); + if (error) + return error; + + dev_info(&pdev->dev, "CPCAP ADC device probed\n"); + + return devm_iio_device_register(&pdev->dev, indio_dev); +} + +static struct platform_driver cpcap_adc_driver = { + .driver = { + .name = "cpcap_adc", + .of_match_table = of_match_ptr(cpcap_adc_id_table), + }, + .probe = cpcap_adc_probe, +}; + +module_platform_driver(cpcap_adc_driver); + +MODULE_ALIAS("platform:cpcap_adc"); +MODULE_DESCRIPTION("CPCAP ADC driver"); +MODULE_AUTHOR("Tony Lindgren <tony@atomide.com"); +MODULE_LICENSE("GPL v2"); |