summaryrefslogtreecommitdiffstats
path: root/drivers/iio/adc/cpcap-adc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/iio/adc/cpcap-adc.c')
-rw-r--r--drivers/iio/adc/cpcap-adc.c1007
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 0000000..62d37f8
--- /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");
OpenPOWER on IntegriCloud