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-rw-r--r--drivers/iio/adc/twl6030-gpadc.c1012
1 files changed, 1012 insertions, 0 deletions
diff --git a/drivers/iio/adc/twl6030-gpadc.c b/drivers/iio/adc/twl6030-gpadc.c
new file mode 100644
index 000000000..765aaee15
--- /dev/null
+++ b/drivers/iio/adc/twl6030-gpadc.c
@@ -0,0 +1,1012 @@
+/*
+ * TWL6030 GPADC module driver
+ *
+ * Copyright (C) 2009-2013 Texas Instruments Inc.
+ * Nishant Kamat <nskamat@ti.com>
+ * Balaji T K <balajitk@ti.com>
+ * Graeme Gregory <gg@slimlogic.co.uk>
+ * Girish S Ghongdemath <girishsg@ti.com>
+ * Ambresh K <ambresh@ti.com>
+ * Oleksandr Kozaruk <oleksandr.kozaruk@ti.com
+ *
+ * Based on twl4030-madc.c
+ * Copyright (C) 2008 Nokia Corporation
+ * Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+#include <linux/mfd/twl.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define DRIVER_NAME "twl6030_gpadc"
+
+/*
+ * twl6030 per TRM has 17 channels, and twl6032 has 19 channels
+ * 2 test network channels are not used,
+ * 2 die temperature channels are not used either, as it is not
+ * defined how to convert ADC value to temperature
+ */
+#define TWL6030_GPADC_USED_CHANNELS 13
+#define TWL6030_GPADC_MAX_CHANNELS 15
+#define TWL6032_GPADC_USED_CHANNELS 15
+#define TWL6032_GPADC_MAX_CHANNELS 19
+#define TWL6030_GPADC_NUM_TRIM_REGS 16
+
+#define TWL6030_GPADC_CTRL_P1 0x05
+
+#define TWL6032_GPADC_GPSELECT_ISB 0x07
+#define TWL6032_GPADC_CTRL_P1 0x08
+
+#define TWL6032_GPADC_GPCH0_LSB 0x0d
+#define TWL6032_GPADC_GPCH0_MSB 0x0e
+
+#define TWL6030_GPADC_CTRL_P1_SP1 BIT(3)
+
+#define TWL6030_GPADC_GPCH0_LSB (0x29)
+
+#define TWL6030_GPADC_RT_SW1_EOC_MASK BIT(5)
+
+#define TWL6030_GPADC_TRIM1 0xCD
+
+#define TWL6030_REG_TOGGLE1 0x90
+#define TWL6030_GPADCS BIT(1)
+#define TWL6030_GPADCR BIT(0)
+
+/**
+ * struct twl6030_chnl_calib - channel calibration
+ * @gain: slope coefficient for ideal curve
+ * @gain_error: gain error
+ * @offset_error: offset of the real curve
+ */
+struct twl6030_chnl_calib {
+ s32 gain;
+ s32 gain_error;
+ s32 offset_error;
+};
+
+/**
+ * struct twl6030_ideal_code - GPADC calibration parameters
+ * GPADC is calibrated in two points: close to the beginning and
+ * to the and of the measurable input range
+ *
+ * @channel: channel number
+ * @code1: ideal code for the input at the beginning
+ * @code2: ideal code for at the end of the range
+ * @volt1: voltage input at the beginning(low voltage)
+ * @volt2: voltage input at the end(high voltage)
+ */
+struct twl6030_ideal_code {
+ int channel;
+ u16 code1;
+ u16 code2;
+ u16 volt1;
+ u16 volt2;
+};
+
+struct twl6030_gpadc_data;
+
+/**
+ * struct twl6030_gpadc_platform_data - platform specific data
+ * @nchannels: number of GPADC channels
+ * @iio_channels: iio channels
+ * @twl6030_ideal: pointer to calibration parameters
+ * @start_conversion: pointer to ADC start conversion function
+ * @channel_to_reg pointer to ADC function to convert channel to
+ * register address for reading conversion result
+ * @calibrate: pointer to calibration function
+ */
+struct twl6030_gpadc_platform_data {
+ const int nchannels;
+ const struct iio_chan_spec *iio_channels;
+ const struct twl6030_ideal_code *ideal;
+ int (*start_conversion)(int channel);
+ u8 (*channel_to_reg)(int channel);
+ int (*calibrate)(struct twl6030_gpadc_data *gpadc);
+};
+
+/**
+ * struct twl6030_gpadc_data - GPADC data
+ * @dev: device pointer
+ * @lock: mutual exclusion lock for the structure
+ * @irq_complete: completion to signal end of conversion
+ * @twl6030_cal_tbl: pointer to calibration data for each
+ * channel with gain error and offset
+ * @pdata: pointer to device specific data
+ */
+struct twl6030_gpadc_data {
+ struct device *dev;
+ struct mutex lock;
+ struct completion irq_complete;
+ struct twl6030_chnl_calib *twl6030_cal_tbl;
+ const struct twl6030_gpadc_platform_data *pdata;
+};
+
+/*
+ * channels 11, 12, 13, 15 and 16 have no calibration data
+ * calibration offset is same for channels 1, 3, 4, 5
+ *
+ * The data is taken from GPADC_TRIM registers description.
+ * GPADC_TRIM registers keep difference between the code measured
+ * at volt1 and volt2 input voltages and corresponding code1 and code2
+ */
+static const struct twl6030_ideal_code
+ twl6030_ideal[TWL6030_GPADC_USED_CHANNELS] = {
+ [0] = { /* ch 0, external, battery type, resistor value */
+ .channel = 0,
+ .code1 = 116,
+ .code2 = 745,
+ .volt1 = 141,
+ .volt2 = 910,
+ },
+ [1] = { /* ch 1, external, battery temperature, NTC resistor value */
+ .channel = 1,
+ .code1 = 82,
+ .code2 = 900,
+ .volt1 = 100,
+ .volt2 = 1100,
+ },
+ [2] = { /* ch 2, external, audio accessory/general purpose */
+ .channel = 2,
+ .code1 = 55,
+ .code2 = 818,
+ .volt1 = 101,
+ .volt2 = 1499,
+ },
+ [3] = { /* ch 3, external, general purpose */
+ .channel = 3,
+ .code1 = 82,
+ .code2 = 900,
+ .volt1 = 100,
+ .volt2 = 1100,
+ },
+ [4] = { /* ch 4, external, temperature measurement/general purpose */
+ .channel = 4,
+ .code1 = 82,
+ .code2 = 900,
+ .volt1 = 100,
+ .volt2 = 1100,
+ },
+ [5] = { /* ch 5, external, general purpose */
+ .channel = 5,
+ .code1 = 82,
+ .code2 = 900,
+ .volt1 = 100,
+ .volt2 = 1100,
+ },
+ [6] = { /* ch 6, external, general purpose */
+ .channel = 6,
+ .code1 = 82,
+ .code2 = 900,
+ .volt1 = 100,
+ .volt2 = 1100,
+ },
+ [7] = { /* ch 7, internal, main battery */
+ .channel = 7,
+ .code1 = 614,
+ .code2 = 941,
+ .volt1 = 3001,
+ .volt2 = 4599,
+ },
+ [8] = { /* ch 8, internal, backup battery */
+ .channel = 8,
+ .code1 = 82,
+ .code2 = 688,
+ .volt1 = 501,
+ .volt2 = 4203,
+ },
+ [9] = { /* ch 9, internal, external charger input */
+ .channel = 9,
+ .code1 = 182,
+ .code2 = 818,
+ .volt1 = 2001,
+ .volt2 = 8996,
+ },
+ [10] = { /* ch 10, internal, VBUS */
+ .channel = 10,
+ .code1 = 149,
+ .code2 = 818,
+ .volt1 = 1001,
+ .volt2 = 5497,
+ },
+ [11] = { /* ch 11, internal, VBUS charging current */
+ .channel = 11,
+ },
+ /* ch 12, internal, Die temperature */
+ /* ch 13, internal, Die temperature */
+ [12] = { /* ch 14, internal, USB ID line */
+ .channel = 14,
+ .code1 = 48,
+ .code2 = 714,
+ .volt1 = 323,
+ .volt2 = 4800,
+ },
+};
+
+static const struct twl6030_ideal_code
+ twl6032_ideal[TWL6032_GPADC_USED_CHANNELS] = {
+ [0] = { /* ch 0, external, battery type, resistor value */
+ .channel = 0,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 440,
+ .volt2 = 1000,
+ },
+ [1] = { /* ch 1, external, battery temperature, NTC resistor value */
+ .channel = 1,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 440,
+ .volt2 = 1000,
+ },
+ [2] = { /* ch 2, external, audio accessory/general purpose */
+ .channel = 2,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 660,
+ .volt2 = 1500,
+ },
+ [3] = { /* ch 3, external, temperature with external diode/general
+ purpose */
+ .channel = 3,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 440,
+ .volt2 = 1000,
+ },
+ [4] = { /* ch 4, external, temperature measurement/general purpose */
+ .channel = 4,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 440,
+ .volt2 = 1000,
+ },
+ [5] = { /* ch 5, external, general purpose */
+ .channel = 5,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 440,
+ .volt2 = 1000,
+ },
+ [6] = { /* ch 6, external, general purpose */
+ .channel = 6,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 440,
+ .volt2 = 1000,
+ },
+ [7] = { /* ch7, internal, system supply */
+ .channel = 7,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 2200,
+ .volt2 = 5000,
+ },
+ [8] = { /* ch8, internal, backup battery */
+ .channel = 8,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 2200,
+ .volt2 = 5000,
+ },
+ [9] = { /* ch 9, internal, external charger input */
+ .channel = 9,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 3960,
+ .volt2 = 9000,
+ },
+ [10] = { /* ch10, internal, VBUS */
+ .channel = 10,
+ .code1 = 150,
+ .code2 = 751,
+ .volt1 = 1000,
+ .volt2 = 5000,
+ },
+ [11] = { /* ch 11, internal, VBUS DC-DC output current */
+ .channel = 11,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 660,
+ .volt2 = 1500,
+ },
+ /* ch 12, internal, Die temperature */
+ /* ch 13, internal, Die temperature */
+ [12] = { /* ch 14, internal, USB ID line */
+ .channel = 14,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 2420,
+ .volt2 = 5500,
+ },
+ /* ch 15, internal, test network */
+ /* ch 16, internal, test network */
+ [13] = { /* ch 17, internal, battery charging current */
+ .channel = 17,
+ },
+ [14] = { /* ch 18, internal, battery voltage */
+ .channel = 18,
+ .code1 = 1441,
+ .code2 = 3276,
+ .volt1 = 2200,
+ .volt2 = 5000,
+ },
+};
+
+static inline int twl6030_gpadc_write(u8 reg, u8 val)
+{
+ return twl_i2c_write_u8(TWL6030_MODULE_GPADC, val, reg);
+}
+
+static inline int twl6030_gpadc_read(u8 reg, u8 *val)
+{
+
+ return twl_i2c_read(TWL6030_MODULE_GPADC, val, reg, 2);
+}
+
+static int twl6030_gpadc_enable_irq(u8 mask)
+{
+ int ret;
+
+ ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_LINE_B);
+ if (ret < 0)
+ return ret;
+
+ ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_STS_B);
+
+ return ret;
+}
+
+static void twl6030_gpadc_disable_irq(u8 mask)
+{
+ twl6030_interrupt_mask(mask, REG_INT_MSK_LINE_B);
+ twl6030_interrupt_mask(mask, REG_INT_MSK_STS_B);
+}
+
+static irqreturn_t twl6030_gpadc_irq_handler(int irq, void *indio_dev)
+{
+ struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
+
+ complete(&gpadc->irq_complete);
+
+ return IRQ_HANDLED;
+}
+
+static int twl6030_start_conversion(int channel)
+{
+ return twl6030_gpadc_write(TWL6030_GPADC_CTRL_P1,
+ TWL6030_GPADC_CTRL_P1_SP1);
+}
+
+static int twl6032_start_conversion(int channel)
+{
+ int ret;
+
+ ret = twl6030_gpadc_write(TWL6032_GPADC_GPSELECT_ISB, channel);
+ if (ret)
+ return ret;
+
+ return twl6030_gpadc_write(TWL6032_GPADC_CTRL_P1,
+ TWL6030_GPADC_CTRL_P1_SP1);
+}
+
+static u8 twl6030_channel_to_reg(int channel)
+{
+ return TWL6030_GPADC_GPCH0_LSB + 2 * channel;
+}
+
+static u8 twl6032_channel_to_reg(int channel)
+{
+ /*
+ * for any prior chosen channel, when the conversion is ready
+ * the result is avalable in GPCH0_LSB, GPCH0_MSB.
+ */
+
+ return TWL6032_GPADC_GPCH0_LSB;
+}
+
+static int twl6030_gpadc_lookup(const struct twl6030_ideal_code *ideal,
+ int channel, int size)
+{
+ int i;
+
+ for (i = 0; i < size; i++)
+ if (ideal[i].channel == channel)
+ break;
+
+ return i;
+}
+
+static int twl6030_channel_calibrated(const struct twl6030_gpadc_platform_data
+ *pdata, int channel)
+{
+ const struct twl6030_ideal_code *ideal = pdata->ideal;
+ int i;
+
+ i = twl6030_gpadc_lookup(ideal, channel, pdata->nchannels);
+ /* not calibrated channels have 0 in all structure members */
+ return pdata->ideal[i].code2;
+}
+
+static int twl6030_gpadc_make_correction(struct twl6030_gpadc_data *gpadc,
+ int channel, int raw_code)
+{
+ const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
+ int corrected_code;
+ int i;
+
+ i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
+ corrected_code = ((raw_code * 1000) -
+ gpadc->twl6030_cal_tbl[i].offset_error) /
+ gpadc->twl6030_cal_tbl[i].gain_error;
+
+ return corrected_code;
+}
+
+static int twl6030_gpadc_get_raw(struct twl6030_gpadc_data *gpadc,
+ int channel, int *res)
+{
+ u8 reg = gpadc->pdata->channel_to_reg(channel);
+ __le16 val;
+ int raw_code;
+ int ret;
+
+ ret = twl6030_gpadc_read(reg, (u8 *)&val);
+ if (ret) {
+ dev_dbg(gpadc->dev, "unable to read register 0x%X\n", reg);
+ return ret;
+ }
+
+ raw_code = le16_to_cpu(val);
+ dev_dbg(gpadc->dev, "GPADC raw code: %d", raw_code);
+
+ if (twl6030_channel_calibrated(gpadc->pdata, channel))
+ *res = twl6030_gpadc_make_correction(gpadc, channel, raw_code);
+ else
+ *res = raw_code;
+
+ return ret;
+}
+
+static int twl6030_gpadc_get_processed(struct twl6030_gpadc_data *gpadc,
+ int channel, int *val)
+{
+ const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
+ int corrected_code;
+ int channel_value;
+ int i;
+ int ret;
+
+ ret = twl6030_gpadc_get_raw(gpadc, channel, &corrected_code);
+ if (ret)
+ return ret;
+
+ i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
+ channel_value = corrected_code *
+ gpadc->twl6030_cal_tbl[i].gain;
+
+ /* Shift back into mV range */
+ channel_value /= 1000;
+
+ dev_dbg(gpadc->dev, "GPADC corrected code: %d", corrected_code);
+ dev_dbg(gpadc->dev, "GPADC value: %d", channel_value);
+
+ *val = channel_value;
+
+ return ret;
+}
+
+static int twl6030_gpadc_read_raw(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ int *val, int *val2, long mask)
+{
+ struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
+ int ret;
+ long timeout;
+
+ mutex_lock(&gpadc->lock);
+
+ ret = gpadc->pdata->start_conversion(chan->channel);
+ if (ret) {
+ dev_err(gpadc->dev, "failed to start conversion\n");
+ goto err;
+ }
+ /* wait for conversion to complete */
+ timeout = wait_for_completion_interruptible_timeout(
+ &gpadc->irq_complete, msecs_to_jiffies(5000));
+ if (timeout == 0) {
+ ret = -ETIMEDOUT;
+ goto err;
+ } else if (timeout < 0) {
+ ret = -EINTR;
+ goto err;
+ }
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = twl6030_gpadc_get_raw(gpadc, chan->channel, val);
+ ret = ret ? -EIO : IIO_VAL_INT;
+ break;
+
+ case IIO_CHAN_INFO_PROCESSED:
+ ret = twl6030_gpadc_get_processed(gpadc, chan->channel, val);
+ ret = ret ? -EIO : IIO_VAL_INT;
+ break;
+
+ default:
+ break;
+ }
+err:
+ mutex_unlock(&gpadc->lock);
+
+ return ret;
+}
+
+/*
+ * The GPADC channels are calibrated using a two point calibration method.
+ * The channels measured with two known values: volt1 and volt2, and
+ * ideal corresponding output codes are known: code1, code2.
+ * The difference(d1, d2) between ideal and measured codes stored in trim
+ * registers.
+ * The goal is to find offset and gain of the real curve for each calibrated
+ * channel.
+ * gain: k = 1 + ((d2 - d1) / (x2 - x1))
+ * offset: b = d1 + (k - 1) * x1
+ */
+static void twl6030_calibrate_channel(struct twl6030_gpadc_data *gpadc,
+ int channel, int d1, int d2)
+{
+ int b, k, gain, x1, x2, i;
+ const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
+
+ i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
+
+ /* Gain */
+ gain = ((ideal[i].volt2 - ideal[i].volt1) * 1000) /
+ (ideal[i].code2 - ideal[i].code1);
+
+ x1 = ideal[i].code1;
+ x2 = ideal[i].code2;
+
+ /* k - real curve gain */
+ k = 1000 + (((d2 - d1) * 1000) / (x2 - x1));
+
+ /* b - offset of the real curve gain */
+ b = (d1 * 1000) - (k - 1000) * x1;
+
+ gpadc->twl6030_cal_tbl[i].gain = gain;
+ gpadc->twl6030_cal_tbl[i].gain_error = k;
+ gpadc->twl6030_cal_tbl[i].offset_error = b;
+
+ dev_dbg(gpadc->dev, "GPADC d1 for Chn: %d = %d\n", channel, d1);
+ dev_dbg(gpadc->dev, "GPADC d2 for Chn: %d = %d\n", channel, d2);
+ dev_dbg(gpadc->dev, "GPADC x1 for Chn: %d = %d\n", channel, x1);
+ dev_dbg(gpadc->dev, "GPADC x2 for Chn: %d = %d\n", channel, x2);
+ dev_dbg(gpadc->dev, "GPADC Gain for Chn: %d = %d\n", channel, gain);
+ dev_dbg(gpadc->dev, "GPADC k for Chn: %d = %d\n", channel, k);
+ dev_dbg(gpadc->dev, "GPADC b for Chn: %d = %d\n", channel, b);
+}
+
+static inline int twl6030_gpadc_get_trim_offset(s8 d)
+{
+ /*
+ * XXX NOTE!
+ * bit 0 - sign, bit 7 - reserved, 6..1 - trim value
+ * though, the documentation states that trim value
+ * is absolute value, the correct conversion results are
+ * obtained if the value is interpreted as 2's complement.
+ */
+ __u32 temp = ((d & 0x7f) >> 1) | ((d & 1) << 6);
+
+ return sign_extend32(temp, 6);
+}
+
+static int twl6030_calibration(struct twl6030_gpadc_data *gpadc)
+{
+ int ret;
+ int chn;
+ u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
+ s8 d1, d2;
+
+ /*
+ * for calibration two measurements have been performed at
+ * factory, for some channels, during the production test and
+ * have been stored in registers. This two stored values are
+ * used to correct the measurements. The values represent
+ * offsets for the given input from the output on ideal curve.
+ */
+ ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
+ TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
+ if (ret < 0) {
+ dev_err(gpadc->dev, "calibration failed\n");
+ return ret;
+ }
+
+ for (chn = 0; chn < TWL6030_GPADC_MAX_CHANNELS; chn++) {
+
+ switch (chn) {
+ case 0:
+ d1 = trim_regs[0];
+ d2 = trim_regs[1];
+ break;
+ case 1:
+ case 3:
+ case 4:
+ case 5:
+ case 6:
+ d1 = trim_regs[4];
+ d2 = trim_regs[5];
+ break;
+ case 2:
+ d1 = trim_regs[12];
+ d2 = trim_regs[13];
+ break;
+ case 7:
+ d1 = trim_regs[6];
+ d2 = trim_regs[7];
+ break;
+ case 8:
+ d1 = trim_regs[2];
+ d2 = trim_regs[3];
+ break;
+ case 9:
+ d1 = trim_regs[8];
+ d2 = trim_regs[9];
+ break;
+ case 10:
+ d1 = trim_regs[10];
+ d2 = trim_regs[11];
+ break;
+ case 14:
+ d1 = trim_regs[14];
+ d2 = trim_regs[15];
+ break;
+ default:
+ continue;
+ }
+
+ d1 = twl6030_gpadc_get_trim_offset(d1);
+ d2 = twl6030_gpadc_get_trim_offset(d2);
+
+ twl6030_calibrate_channel(gpadc, chn, d1, d2);
+ }
+
+ return 0;
+}
+
+static int twl6032_get_trim_value(u8 *trim_regs, unsigned int reg0,
+ unsigned int reg1, unsigned int mask0, unsigned int mask1,
+ unsigned int shift0)
+{
+ int val;
+
+ val = (trim_regs[reg0] & mask0) << shift0;
+ val |= (trim_regs[reg1] & mask1) >> 1;
+ if (trim_regs[reg1] & 0x01)
+ val = -val;
+
+ return val;
+}
+
+static int twl6032_calibration(struct twl6030_gpadc_data *gpadc)
+{
+ int chn, d1 = 0, d2 = 0, temp;
+ u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
+ int ret;
+
+ ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
+ TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
+ if (ret < 0) {
+ dev_err(gpadc->dev, "calibration failed\n");
+ return ret;
+ }
+
+ /*
+ * Loop to calculate the value needed for returning voltages from
+ * GPADC not values.
+ *
+ * gain is calculated to 3 decimal places fixed point.
+ */
+ for (chn = 0; chn < TWL6032_GPADC_MAX_CHANNELS; chn++) {
+
+ switch (chn) {
+ case 0:
+ case 1:
+ case 2:
+ case 3:
+ case 4:
+ case 5:
+ case 6:
+ case 11:
+ case 14:
+ d1 = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
+ 0x06, 2);
+ d2 = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
+ 0x06, 2);
+ break;
+ case 8:
+ temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
+ 0x06, 2);
+ d1 = temp + twl6032_get_trim_value(trim_regs, 7, 6,
+ 0x18, 0x1E, 1);
+
+ temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3F,
+ 0x06, 2);
+ d2 = temp + twl6032_get_trim_value(trim_regs, 9, 7,
+ 0x1F, 0x06, 2);
+ break;
+ case 9:
+ temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
+ 0x06, 2);
+ d1 = temp + twl6032_get_trim_value(trim_regs, 13, 11,
+ 0x18, 0x1E, 1);
+
+ temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
+ 0x06, 2);
+ d2 = temp + twl6032_get_trim_value(trim_regs, 15, 13,
+ 0x1F, 0x06, 1);
+ break;
+ case 10:
+ d1 = twl6032_get_trim_value(trim_regs, 10, 8, 0x0f,
+ 0x0E, 3);
+ d2 = twl6032_get_trim_value(trim_regs, 14, 12, 0x0f,
+ 0x0E, 3);
+ break;
+ case 7:
+ case 18:
+ temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
+ 0x06, 2);
+
+ d1 = (trim_regs[4] & 0x7E) >> 1;
+ if (trim_regs[4] & 0x01)
+ d1 = -d1;
+ d1 += temp;
+
+ temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
+ 0x06, 2);
+
+ d2 = (trim_regs[5] & 0xFE) >> 1;
+ if (trim_regs[5] & 0x01)
+ d2 = -d2;
+
+ d2 += temp;
+ break;
+ default:
+ /* No data for other channels */
+ continue;
+ }
+
+ twl6030_calibrate_channel(gpadc, chn, d1, d2);
+ }
+
+ return 0;
+}
+
+#define TWL6030_GPADC_CHAN(chn, _type, chan_info) { \
+ .type = _type, \
+ .channel = chn, \
+ .info_mask_separate = BIT(chan_info), \
+ .indexed = 1, \
+}
+
+static const struct iio_chan_spec twl6030_gpadc_iio_channels[] = {
+ TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
+ TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
+ TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
+ TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+};
+
+static const struct iio_chan_spec twl6032_gpadc_iio_channels[] = {
+ TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
+ TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
+ TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+ TWL6030_GPADC_CHAN(17, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
+ TWL6030_GPADC_CHAN(18, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+};
+
+static const struct iio_info twl6030_gpadc_iio_info = {
+ .read_raw = &twl6030_gpadc_read_raw,
+};
+
+static const struct twl6030_gpadc_platform_data twl6030_pdata = {
+ .iio_channels = twl6030_gpadc_iio_channels,
+ .nchannels = TWL6030_GPADC_USED_CHANNELS,
+ .ideal = twl6030_ideal,
+ .start_conversion = twl6030_start_conversion,
+ .channel_to_reg = twl6030_channel_to_reg,
+ .calibrate = twl6030_calibration,
+};
+
+static const struct twl6030_gpadc_platform_data twl6032_pdata = {
+ .iio_channels = twl6032_gpadc_iio_channels,
+ .nchannels = TWL6032_GPADC_USED_CHANNELS,
+ .ideal = twl6032_ideal,
+ .start_conversion = twl6032_start_conversion,
+ .channel_to_reg = twl6032_channel_to_reg,
+ .calibrate = twl6032_calibration,
+};
+
+static const struct of_device_id of_twl6030_match_tbl[] = {
+ {
+ .compatible = "ti,twl6030-gpadc",
+ .data = &twl6030_pdata,
+ },
+ {
+ .compatible = "ti,twl6032-gpadc",
+ .data = &twl6032_pdata,
+ },
+ { /* end */ }
+};
+MODULE_DEVICE_TABLE(of, of_twl6030_match_tbl);
+
+static int twl6030_gpadc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct twl6030_gpadc_data *gpadc;
+ const struct twl6030_gpadc_platform_data *pdata;
+ const struct of_device_id *match;
+ struct iio_dev *indio_dev;
+ int irq;
+ int ret;
+
+ match = of_match_device(of_twl6030_match_tbl, dev);
+ if (!match)
+ return -EINVAL;
+
+ pdata = match->data;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ gpadc = iio_priv(indio_dev);
+
+ gpadc->twl6030_cal_tbl = devm_kcalloc(dev,
+ pdata->nchannels,
+ sizeof(*gpadc->twl6030_cal_tbl),
+ GFP_KERNEL);
+ if (!gpadc->twl6030_cal_tbl)
+ return -ENOMEM;
+
+ gpadc->dev = dev;
+ gpadc->pdata = pdata;
+
+ platform_set_drvdata(pdev, indio_dev);
+ mutex_init(&gpadc->lock);
+ init_completion(&gpadc->irq_complete);
+
+ ret = pdata->calibrate(gpadc);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to read calibration registers\n");
+ return ret;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "failed to get irq\n");
+ return irq;
+ }
+
+ ret = devm_request_threaded_irq(dev, irq, NULL,
+ twl6030_gpadc_irq_handler,
+ IRQF_ONESHOT, "twl6030_gpadc", indio_dev);
+ if (ret)
+ return ret;
+
+ ret = twl6030_gpadc_enable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable GPADC interrupt\n");
+ return ret;
+ }
+
+ ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
+ TWL6030_REG_TOGGLE1);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable GPADC module\n");
+ return ret;
+ }
+
+ indio_dev->name = DRIVER_NAME;
+ indio_dev->dev.parent = dev;
+ indio_dev->info = &twl6030_gpadc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = pdata->iio_channels;
+ indio_dev->num_channels = pdata->nchannels;
+
+ return iio_device_register(indio_dev);
+}
+
+static int twl6030_gpadc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+
+ twl6030_gpadc_disable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
+ iio_device_unregister(indio_dev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int twl6030_gpadc_suspend(struct device *pdev)
+{
+ int ret;
+
+ ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCR,
+ TWL6030_REG_TOGGLE1);
+ if (ret)
+ dev_err(pdev, "error resetting GPADC (%d)!\n", ret);
+
+ return 0;
+};
+
+static int twl6030_gpadc_resume(struct device *pdev)
+{
+ int ret;
+
+ ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
+ TWL6030_REG_TOGGLE1);
+ if (ret)
+ dev_err(pdev, "error setting GPADC (%d)!\n", ret);
+
+ return 0;
+};
+#endif
+
+static SIMPLE_DEV_PM_OPS(twl6030_gpadc_pm_ops, twl6030_gpadc_suspend,
+ twl6030_gpadc_resume);
+
+static struct platform_driver twl6030_gpadc_driver = {
+ .probe = twl6030_gpadc_probe,
+ .remove = twl6030_gpadc_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .pm = &twl6030_gpadc_pm_ops,
+ .of_match_table = of_twl6030_match_tbl,
+ },
+};
+
+module_platform_driver(twl6030_gpadc_driver);
+
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
+MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
+MODULE_AUTHOR("Oleksandr Kozaruk <oleksandr.kozaruk@ti.com");
+MODULE_DESCRIPTION("twl6030 ADC driver");
+MODULE_LICENSE("GPL");