On 07/25/13 14:26, Oleksandr Kozaruk wrote: > The GPADC is general purpose ADC found on TWL6030, and TWL6032 PMIC, > known also as Phoenix and PhoenixLite. > > The TWL6030 and TWL6032 have GPADC with 17 and 19 channels > respectively. Some channels have current source and are used for > measuring voltage drop on resistive load for detecting battery ID > resistance, or measuring voltage drop on NTC resistors for external > temperature measurements. Some channels measure voltage, (i.e. battery > voltage), and have voltage dividers, thus, capable to scale voltage. > Some channels are dedicated for measuring die temperature. > > Some channels are calibrated in 2 points, having offsets from ideal > values kept in trim registers. This is used to correct measurements. > > The differences between GPADC in TWL6030 and TWL6032: > - 10 bit vs 12 bit ADC; > - 17 vs 19 channels; > - channels have different purpose(i.e. battery voltage > channel 8 vs channel 18); > - trim values are interpreted differently. > > Based on the driver patched from Balaji TK, Graeme Gregory, Ambresh K, > Girish S Ghongdemath. > > Signed-off-by: Balaji T K <balajitk@xxxxxx> > Signed-off-by: Graeme Gregory <gg@xxxxxxxxxxxxxxx> > Signed-off-by: Oleksandr Kozaruk <oleksandr.kozaruk@xxxxxx> Multiple authors are done by having multiple MODULE_AUTHOR lines rather as one long string. See include/linux/module.h. I fixed that up and dealt with some trivial fuzz in the makefile/Kconfig. You might want to take advantage of devm_iio_allocate_device which has been introduced in the meantime and greatly simplifies error paths in IIO probe functions. Anyhow, applied to the togreg branch of iio.git Note I haven't taken the device tree patch. For that I would need and ack from the relevant maintainer(s). Personally I'd rather not touch device tree files unless i have to due to the high chance of merge conflicts occuring. I would expect the subarch maintainer to pick that one up (or to ask me to ;) Nice relatively clean driver for a somewhat 'interesting' bit of hardware. Thanks Jonathan > --- > drivers/iio/adc/Kconfig | 14 + > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/twl6030-gpadc.c | 1027 +++++++++++++++++++++++++++++++++++++++ > 3 files changed, 1042 insertions(+) > create mode 100644 drivers/iio/adc/twl6030-gpadc.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 93129ec..f8f9f18 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -160,6 +160,20 @@ config TI_AM335X_ADC > Say yes here to build support for Texas Instruments ADC > driver which is also a MFD client. > > +config TWL6030_GPADC > + tristate "TWL6030 GPADC (General Purpose A/D Converter) Support" > + depends on TWL4030_CORE > + default n > + help > + Say yes here if you want support for the TWL6030/TWL6032 General > + Purpose A/D Converter. This will add support for battery type > + detection, battery voltage and temperature measurement, die > + temperature measurement, system supply voltage, audio accessory, > + USB ID detection. > + > + This driver can also be built as a module. If so, the module will be > + called twl6030-gpadc. > + > config VIPERBOARD_ADC > tristate "Viperboard ADC support" > depends on MFD_VIPERBOARD && USB > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 8f475d3..db430bd 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -17,4 +17,5 @@ obj-$(CONFIG_MAX1363) += max1363.o > obj-$(CONFIG_MCP320X) += mcp320x.o > obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o > obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o > +obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o > obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o > diff --git a/drivers/iio/adc/twl6030-gpadc.c b/drivers/iio/adc/twl6030-gpadc.c > new file mode 100644 > index 0000000..2b63083 > --- /dev/null > +++ b/drivers/iio/adc/twl6030-gpadc.c > @@ -0,0 +1,1027 @@ > +/* > + * TWL6030 GPADC module driver > + * > + * Copyright (C) 2009-2013 Texas Instruments Inc. > + * Nishant Kamat <nskamat@xxxxxx> > + * Balaji T K <balajitk@xxxxxx> > + * Graeme Gregory <gg@xxxxxxxxxxxxxxx> > + * Girish S Ghongdemath <girishsg@xxxxxx> > + * Ambresh K <ambresh@xxxxxx> > + * Oleksandr Kozaruk <oleksandr.kozaruk@xxxxxx > + * > + * Based on twl4030-madc.c > + * Copyright (C) 2008 Nokia Corporation > + * Mikko Ylinen <mikko.k.ylinen@xxxxxxxxx> > + * > + * 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/init.h> > +#include <linux/interrupt.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/of_platform.h> > +#include <linux/i2c/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) { > + goto err; > + ret = -EINTR; > + } > + > + 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, > + .driver_module = THIS_MODULE, > +}; > + > +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 */ } > +}; > + > +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_match_ptr(of_twl6030_match_tbl), dev); > + if (!match) > + return -EINVAL; > + > + pdata = match->data; > + > + indio_dev = iio_device_alloc(sizeof(*gpadc)); > + if (!indio_dev) { > + dev_err(dev, "failed allocating iio device\n"); > + ret = -ENOMEM; > + } > + > + gpadc = iio_priv(indio_dev); > + > + gpadc->twl6030_cal_tbl = devm_kzalloc(dev, > + sizeof(*gpadc->twl6030_cal_tbl) * > + pdata->nchannels, GFP_KERNEL); > + if (!gpadc->twl6030_cal_tbl) > + goto err_free_device; > + > + 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"); > + goto err_free_device; > + } > + > + irq = platform_get_irq(pdev, 0); > + if (irq < 0) { > + dev_err(&pdev->dev, "failed to get irq\n"); > + goto err_free_device; > + } > + > + ret = request_threaded_irq(irq, NULL, twl6030_gpadc_irq_handler, > + IRQF_ONESHOT, "twl6030_gpadc", indio_dev); > + if (ret) { > + dev_dbg(&pdev->dev, "could not request irq\n"); > + goto err_free_device; > + } > + > + ret = twl6030_gpadc_enable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK); > + if (ret < 0) { > + dev_err(&pdev->dev, "failed to enable GPADC interrupt\n"); > + goto err_free_irq; > + } > + > + 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"); > + goto err_free_irq; > + } > + > + 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; > + > + ret = iio_device_register(indio_dev); > + if (ret) > + goto err_free_irq; > + > + return ret; > + > +err_free_irq: > + free_irq(irq, indio_dev); > +err_free_device: > + iio_device_free(indio_dev); > + > + return ret; > +} > + > +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); > + free_irq(platform_get_irq(pdev, 0), indio_dev); > + iio_device_unregister(indio_dev); > + iio_device_free(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 reseting 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, > + .owner = THIS_MODULE, > + .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@xxxxxx>, Graeme Gregory <gg@xxxxxxxxxxxxxxx>, Oleksandr Kozaruk <oleksandr.kozaruk@xxxxxx"); > +MODULE_DESCRIPTION("twl6030 ADC driver"); > +MODULE_LICENSE("GPL"); > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html