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linux-zen-desktop/drivers/iio/light/rohm-bu27008.c

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6.5.5
2023-10-24 12:59:35 +02:00
// SPDX-License-Identifier: GPL-2.0-only
/*
* BU27008 ROHM Colour Sensor
*
* Copyright (c) 2023, ROHM Semiconductor.
*/
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/units.h>
#include <linux/iio/iio.h>
#include <linux/iio/iio-gts-helper.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#define BU27008_REG_SYSTEM_CONTROL 0x40
#define BU27008_MASK_SW_RESET BIT(7)
#define BU27008_MASK_PART_ID GENMASK(5, 0)
#define BU27008_ID 0x1a
#define BU27008_REG_MODE_CONTROL1 0x41
#define BU27008_MASK_MEAS_MODE GENMASK(2, 0)
#define BU27008_MASK_CHAN_SEL GENMASK(3, 2)
#define BU27008_REG_MODE_CONTROL2 0x42
#define BU27008_MASK_RGBC_GAIN GENMASK(7, 3)
#define BU27008_MASK_IR_GAIN_LO GENMASK(2, 0)
#define BU27008_SHIFT_IR_GAIN 3
#define BU27008_REG_MODE_CONTROL3 0x43
#define BU27008_MASK_VALID BIT(7)
#define BU27008_MASK_INT_EN BIT(1)
#define BU27008_INT_EN BU27008_MASK_INT_EN
#define BU27008_INT_DIS 0
#define BU27008_MASK_MEAS_EN BIT(0)
#define BU27008_MEAS_EN BIT(0)
#define BU27008_MEAS_DIS 0
#define BU27008_REG_DATA0_LO 0x50
#define BU27008_REG_DATA1_LO 0x52
#define BU27008_REG_DATA2_LO 0x54
#define BU27008_REG_DATA3_LO 0x56
#define BU27008_REG_DATA3_HI 0x57
#define BU27008_REG_MANUFACTURER_ID 0x92
#define BU27008_REG_MAX BU27008_REG_MANUFACTURER_ID
/**
* enum bu27008_chan_type - BU27008 channel types
* @BU27008_RED: Red channel. Always via data0.
* @BU27008_GREEN: Green channel. Always via data1.
* @BU27008_BLUE: Blue channel. Via data2 (when used).
* @BU27008_CLEAR: Clear channel. Via data2 or data3 (when used).
* @BU27008_IR: IR channel. Via data3 (when used).
* @BU27008_NUM_CHANS: Number of channel types.
*/
enum bu27008_chan_type {
BU27008_RED,
BU27008_GREEN,
BU27008_BLUE,
BU27008_CLEAR,
BU27008_IR,
BU27008_NUM_CHANS
};
/**
* enum bu27008_chan - BU27008 physical data channel
* @BU27008_DATA0: Always red.
* @BU27008_DATA1: Always green.
* @BU27008_DATA2: Blue or clear.
* @BU27008_DATA3: IR or clear.
* @BU27008_NUM_HW_CHANS: Number of physical channels
*/
enum bu27008_chan {
BU27008_DATA0,
BU27008_DATA1,
BU27008_DATA2,
BU27008_DATA3,
BU27008_NUM_HW_CHANS
};
/* We can always measure red and green at same time */
#define ALWAYS_SCANNABLE (BIT(BU27008_RED) | BIT(BU27008_GREEN))
/* We use these data channel configs. Ensure scan_masks below follow them too */
#define BU27008_BLUE2_CLEAR3 0x0 /* buffer is R, G, B, C */
#define BU27008_CLEAR2_IR3 0x1 /* buffer is R, G, C, IR */
#define BU27008_BLUE2_IR3 0x2 /* buffer is R, G, B, IR */
static const unsigned long bu27008_scan_masks[] = {
/* buffer is R, G, B, C */
ALWAYS_SCANNABLE | BIT(BU27008_BLUE) | BIT(BU27008_CLEAR),
/* buffer is R, G, C, IR */
ALWAYS_SCANNABLE | BIT(BU27008_CLEAR) | BIT(BU27008_IR),
/* buffer is R, G, B, IR */
ALWAYS_SCANNABLE | BIT(BU27008_BLUE) | BIT(BU27008_IR),
0
};
/*
* Available scales with gain 1x - 1024x, timings 55, 100, 200, 400 mS
* Time impacts to gain: 1x, 2x, 4x, 8x.
*
* => Max total gain is HWGAIN * gain by integration time (8 * 1024) = 8192
*
* Max amplification is (HWGAIN * MAX integration-time multiplier) 1024 * 8
* = 8192. With NANO scale we get rid of accuracy loss when we start with the
* scale 16.0 for HWGAIN1, INT-TIME 55 mS. This way the nano scale for MAX
* total gain 8192 will be 1953125
*/
#define BU27008_SCALE_1X 16
/* See the data sheet for the "Gain Setting" table */
#define BU27008_GSEL_1X 0x00
#define BU27008_GSEL_4X 0x08
#define BU27008_GSEL_8X 0x09
#define BU27008_GSEL_16X 0x0a
#define BU27008_GSEL_32X 0x0b
#define BU27008_GSEL_64X 0x0c
#define BU27008_GSEL_256X 0x18
#define BU27008_GSEL_512X 0x19
#define BU27008_GSEL_1024X 0x1a
static const struct iio_gain_sel_pair bu27008_gains[] = {
GAIN_SCALE_GAIN(1, BU27008_GSEL_1X),
GAIN_SCALE_GAIN(4, BU27008_GSEL_4X),
GAIN_SCALE_GAIN(8, BU27008_GSEL_8X),
GAIN_SCALE_GAIN(16, BU27008_GSEL_16X),
GAIN_SCALE_GAIN(32, BU27008_GSEL_32X),
GAIN_SCALE_GAIN(64, BU27008_GSEL_64X),
GAIN_SCALE_GAIN(256, BU27008_GSEL_256X),
GAIN_SCALE_GAIN(512, BU27008_GSEL_512X),
GAIN_SCALE_GAIN(1024, BU27008_GSEL_1024X),
};
static const struct iio_gain_sel_pair bu27008_gains_ir[] = {
GAIN_SCALE_GAIN(2, BU27008_GSEL_1X),
GAIN_SCALE_GAIN(4, BU27008_GSEL_4X),
GAIN_SCALE_GAIN(8, BU27008_GSEL_8X),
GAIN_SCALE_GAIN(16, BU27008_GSEL_16X),
GAIN_SCALE_GAIN(32, BU27008_GSEL_32X),
GAIN_SCALE_GAIN(64, BU27008_GSEL_64X),
GAIN_SCALE_GAIN(256, BU27008_GSEL_256X),
GAIN_SCALE_GAIN(512, BU27008_GSEL_512X),
GAIN_SCALE_GAIN(1024, BU27008_GSEL_1024X),
};
#define BU27008_MEAS_MODE_100MS 0x00
#define BU27008_MEAS_MODE_55MS 0x01
#define BU27008_MEAS_MODE_200MS 0x02
#define BU27008_MEAS_MODE_400MS 0x04
#define BU27008_MEAS_TIME_MAX_MS 400
static const struct iio_itime_sel_mul bu27008_itimes[] = {
GAIN_SCALE_ITIME_US(400000, BU27008_MEAS_MODE_400MS, 8),
GAIN_SCALE_ITIME_US(200000, BU27008_MEAS_MODE_200MS, 4),
GAIN_SCALE_ITIME_US(100000, BU27008_MEAS_MODE_100MS, 2),
GAIN_SCALE_ITIME_US(55000, BU27008_MEAS_MODE_55MS, 1),
};
/*
* All the RGBC channels share the same gain.
* IR gain can be fine-tuned from the gain set for the RGBC by 2 bit, but this
* would yield quite complex gain setting. Especially since not all bit
* compinations are supported. And in any case setting GAIN for RGBC will
* always also change the IR-gain.
*
* On top of this, the selector '0' which corresponds to hw-gain 1X on RGBC,
* corresponds to gain 2X on IR. Rest of the selctors correspond to same gains
* though. This, however, makes it not possible to use shared gain for all
* RGBC and IR settings even though they are all changed at the one go.
*/
#define BU27008_CHAN(color, data, separate_avail) \
{ \
.type = IIO_INTENSITY, \
.modified = 1, \
.channel2 = IIO_MOD_LIGHT_##color, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_SCALE), \
.info_mask_separate_available = (separate_avail), \
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), \
.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME), \
.address = BU27008_REG_##data##_LO, \
.scan_index = BU27008_##color, \
.scan_type = { \
.sign = 'u', \
.realbits = 16, \
.storagebits = 16, \
.endianness = IIO_LE, \
}, \
}
/* For raw reads we always configure DATA3 for CLEAR */
static const struct iio_chan_spec bu27008_channels[] = {
BU27008_CHAN(RED, DATA0, BIT(IIO_CHAN_INFO_SCALE)),
BU27008_CHAN(GREEN, DATA1, BIT(IIO_CHAN_INFO_SCALE)),
BU27008_CHAN(BLUE, DATA2, BIT(IIO_CHAN_INFO_SCALE)),
BU27008_CHAN(CLEAR, DATA2, BIT(IIO_CHAN_INFO_SCALE)),
/*
* We don't allow setting scale for IR (because of shared gain bits).
* Hence we don't advertise available ones either.
*/
BU27008_CHAN(IR, DATA3, 0),
IIO_CHAN_SOFT_TIMESTAMP(BU27008_NUM_CHANS),
};
struct bu27008_data {
struct regmap *regmap;
struct iio_trigger *trig;
struct device *dev;
struct iio_gts gts;
struct iio_gts gts_ir;
int irq;
/*
* Prevent changing gain/time config when scale is read/written.
* Similarly, protect the integration_time read/change sequence.
* Prevent changing gain/time when data is read.
*/
struct mutex mutex;
};
static const struct regmap_range bu27008_volatile_ranges[] = {
{
.range_min = BU27008_REG_SYSTEM_CONTROL, /* SWRESET */
.range_max = BU27008_REG_SYSTEM_CONTROL,
}, {
.range_min = BU27008_REG_MODE_CONTROL3, /* VALID */
.range_max = BU27008_REG_MODE_CONTROL3,
}, {
.range_min = BU27008_REG_DATA0_LO, /* DATA */
.range_max = BU27008_REG_DATA3_HI,
},
};
static const struct regmap_access_table bu27008_volatile_regs = {
.yes_ranges = &bu27008_volatile_ranges[0],
.n_yes_ranges = ARRAY_SIZE(bu27008_volatile_ranges),
};
static const struct regmap_range bu27008_read_only_ranges[] = {
{
.range_min = BU27008_REG_DATA0_LO,
.range_max = BU27008_REG_DATA3_HI,
}, {
.range_min = BU27008_REG_MANUFACTURER_ID,
.range_max = BU27008_REG_MANUFACTURER_ID,
},
};
static const struct regmap_access_table bu27008_ro_regs = {
.no_ranges = &bu27008_read_only_ranges[0],
.n_no_ranges = ARRAY_SIZE(bu27008_read_only_ranges),
};
static const struct regmap_config bu27008_regmap = {
.reg_bits = 8,
.val_bits = 8,
.max_register = BU27008_REG_MAX,
.cache_type = REGCACHE_RBTREE,
.volatile_table = &bu27008_volatile_regs,
.wr_table = &bu27008_ro_regs,
/*
* All register writes are serialized by the mutex which protects the
* scale setting/getting. This is needed because scale is combined by
* gain and integration time settings and we need to ensure those are
* not read / written when scale is being computed.
*
* As a result of this serializing, we don't need regmap locking. Note,
* this is not true if we add any configurations which are not
* serialized by the mutex and which may need for example a protected
* read-modify-write cycle (eg. regmap_update_bits()). Please, revise
* this when adding features to the driver.
*/
.disable_locking = true,
};
#define BU27008_MAX_VALID_RESULT_WAIT_US 50000
#define BU27008_VALID_RESULT_WAIT_QUANTA_US 1000
static int bu27008_chan_read_data(struct bu27008_data *data, int reg, int *val)
{
int ret, valid;
__le16 tmp;
ret = regmap_read_poll_timeout(data->regmap, BU27008_REG_MODE_CONTROL3,
valid, (valid & BU27008_MASK_VALID),
BU27008_VALID_RESULT_WAIT_QUANTA_US,
BU27008_MAX_VALID_RESULT_WAIT_US);
if (ret)
return ret;
ret = regmap_bulk_read(data->regmap, reg, &tmp, sizeof(tmp));
if (ret)
dev_err(data->dev, "Reading channel data failed\n");
*val = le16_to_cpu(tmp);
return ret;
}
static int bu27008_get_gain(struct bu27008_data *data, struct iio_gts *gts, int *gain)
{
int ret, sel;
ret = regmap_read(data->regmap, BU27008_REG_MODE_CONTROL2, &sel);
if (ret)
return ret;
sel = FIELD_GET(BU27008_MASK_RGBC_GAIN, sel);
ret = iio_gts_find_gain_by_sel(gts, sel);
if (ret < 0) {
dev_err(data->dev, "unknown gain value 0x%x\n", sel);
return ret;
}
*gain = ret;
return 0;
}
static int bu27008_write_gain_sel(struct bu27008_data *data, int sel)
{
int regval;
regval = FIELD_PREP(BU27008_MASK_RGBC_GAIN, sel);
/*
* We do always set also the LOW bits of IR-gain because othervice we
* would risk resulting an invalid GAIN register value.
*
* We could allow setting separate gains for RGBC and IR when the
* values were such that HW could support both gain settings.
* Eg, when the shared bits were same for both gain values.
*
* This, however, has a negligible benefit compared to the increased
* software complexity when we would need to go through the gains
* for both channels separately when the integration time changes.
* This would end up with nasty logic for computing gain values for
* both channels - and rejecting them if shared bits changed.
*
* We should then build the logic by guessing what a user prefers.
* RGBC or IR gains correctly set while other jumps to odd value?
* Maybe look-up a value where both gains are somehow optimized
* <what this somehow is, is ATM unknown to us>. Or maybe user would
* expect us to reject changes when optimal gains can't be set to both
* channels w/given integration time. At best that would result
* solution that works well for a very specific subset of
* configurations but causes unexpected corner-cases.
*
* So, we keep it simple. Always set same selector to IR and RGBC.
* We disallow setting IR (as I expect that most of the users are
* interested in RGBC). This way we can show the user that the scales
* for RGBC and IR channels are different (1X Vs 2X with sel 0) while
* still keeping the operation deterministic.
*/
regval |= FIELD_PREP(BU27008_MASK_IR_GAIN_LO, sel);
return regmap_update_bits(data->regmap, BU27008_REG_MODE_CONTROL2,
BU27008_MASK_RGBC_GAIN, regval);
}
static int bu27008_set_gain(struct bu27008_data *data, int gain)
{
int ret;
ret = iio_gts_find_sel_by_gain(&data->gts, gain);
if (ret < 0)
return ret;
return bu27008_write_gain_sel(data, ret);
}
static int bu27008_get_int_time_sel(struct bu27008_data *data, int *sel)
{
int ret, val;
ret = regmap_read(data->regmap, BU27008_REG_MODE_CONTROL1, &val);
*sel = FIELD_GET(BU27008_MASK_MEAS_MODE, val);
return ret;
}
static int bu27008_set_int_time_sel(struct bu27008_data *data, int sel)
{
return regmap_update_bits(data->regmap, BU27008_REG_MODE_CONTROL1,
BU27008_MASK_MEAS_MODE, sel);
}
static int bu27008_get_int_time_us(struct bu27008_data *data)
{
int ret, sel;
ret = bu27008_get_int_time_sel(data, &sel);
if (ret)
return ret;
return iio_gts_find_int_time_by_sel(&data->gts, sel);
}
static int _bu27008_get_scale(struct bu27008_data *data, bool ir, int *val,
int *val2)
{
struct iio_gts *gts;
int gain, ret;
if (ir)
gts = &data->gts_ir;
else
gts = &data->gts;
ret = bu27008_get_gain(data, gts, &gain);
if (ret)
return ret;
ret = bu27008_get_int_time_us(data);
if (ret < 0)
return ret;
return iio_gts_get_scale(gts, gain, ret, val, val2);
}
static int bu27008_get_scale(struct bu27008_data *data, bool ir, int *val,
int *val2)
{
int ret;
mutex_lock(&data->mutex);
ret = _bu27008_get_scale(data, ir, val, val2);
mutex_unlock(&data->mutex);
return ret;
}
static int bu27008_set_int_time(struct bu27008_data *data, int time)
{
int ret;
ret = iio_gts_find_sel_by_int_time(&data->gts, time);
if (ret < 0)
return ret;
return regmap_update_bits(data->regmap, BU27008_REG_MODE_CONTROL1,
BU27008_MASK_MEAS_MODE, ret);
}
/* Try to change the time so that the scale is maintained */
static int bu27008_try_set_int_time(struct bu27008_data *data, int int_time_new)
{
int ret, old_time_sel, new_time_sel, old_gain, new_gain;
mutex_lock(&data->mutex);
ret = bu27008_get_int_time_sel(data, &old_time_sel);
if (ret < 0)
goto unlock_out;
if (!iio_gts_valid_time(&data->gts, int_time_new)) {
dev_dbg(data->dev, "Unsupported integration time %u\n",
int_time_new);
ret = -EINVAL;
goto unlock_out;
}
/* If we already use requested time, then we're done */
new_time_sel = iio_gts_find_sel_by_int_time(&data->gts, int_time_new);
if (new_time_sel == old_time_sel)
goto unlock_out;
ret = bu27008_get_gain(data, &data->gts, &old_gain);
if (ret)
goto unlock_out;
ret = iio_gts_find_new_gain_sel_by_old_gain_time(&data->gts, old_gain,
old_time_sel, new_time_sel, &new_gain);
if (ret) {
int scale1, scale2;
bool ok;
_bu27008_get_scale(data, false, &scale1, &scale2);
dev_dbg(data->dev,
"Can't support time %u with current scale %u %u\n",
int_time_new, scale1, scale2);
if (new_gain < 0)
goto unlock_out;
/*
* If caller requests for integration time change and we
* can't support the scale - then the caller should be
* prepared to 'pick up the pieces and deal with the
* fact that the scale changed'.
*/
ret = iio_find_closest_gain_low(&data->gts, new_gain, &ok);
if (!ok)
dev_dbg(data->dev, "optimal gain out of range\n");
if (ret < 0) {
dev_dbg(data->dev,
"Total gain increase. Risk of saturation");
ret = iio_gts_get_min_gain(&data->gts);
if (ret < 0)
goto unlock_out;
}
new_gain = ret;
dev_dbg(data->dev, "scale changed, new gain %u\n", new_gain);
}
ret = bu27008_set_gain(data, new_gain);
if (ret)
goto unlock_out;
ret = bu27008_set_int_time(data, int_time_new);
unlock_out:
mutex_unlock(&data->mutex);
return ret;
}
static int bu27008_meas_set(struct bu27008_data *data, int state)
{
return regmap_update_bits(data->regmap, BU27008_REG_MODE_CONTROL3,
BU27008_MASK_MEAS_EN, state);
}
static int bu27008_chan_cfg(struct bu27008_data *data,
struct iio_chan_spec const *chan)
{
int chan_sel;
if (chan->scan_index == BU27008_BLUE)
chan_sel = BU27008_BLUE2_CLEAR3;
else
chan_sel = BU27008_CLEAR2_IR3;
chan_sel = FIELD_PREP(BU27008_MASK_CHAN_SEL, chan_sel);
return regmap_update_bits(data->regmap, BU27008_REG_MODE_CONTROL3,
BU27008_MASK_CHAN_SEL, chan_sel);
}
static int bu27008_read_one(struct bu27008_data *data, struct iio_dev *idev,
struct iio_chan_spec const *chan, int *val, int *val2)
{
int ret, int_time;
ret = bu27008_chan_cfg(data, chan);
if (ret)
return ret;
ret = bu27008_meas_set(data, BU27008_MEAS_EN);
if (ret)
return ret;
ret = bu27008_get_int_time_us(data);
if (ret < 0)
int_time = BU27008_MEAS_TIME_MAX_MS;
else
int_time = ret / USEC_PER_MSEC;
msleep(int_time);
ret = bu27008_chan_read_data(data, chan->address, val);
if (!ret)
ret = IIO_VAL_INT;
if (bu27008_meas_set(data, BU27008_MEAS_DIS))
dev_warn(data->dev, "measurement disabling failed\n");
return ret;
}
static int bu27008_read_raw(struct iio_dev *idev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct bu27008_data *data = iio_priv(idev);
int busy, ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
busy = iio_device_claim_direct_mode(idev);
if (busy)
return -EBUSY;
mutex_lock(&data->mutex);
ret = bu27008_read_one(data, idev, chan, val, val2);
mutex_unlock(&data->mutex);
iio_device_release_direct_mode(idev);
return ret;
case IIO_CHAN_INFO_SCALE:
ret = bu27008_get_scale(data, chan->scan_index == BU27008_IR,
val, val2);
if (ret)
return ret;
return IIO_VAL_INT_PLUS_NANO;
case IIO_CHAN_INFO_INT_TIME:
ret = bu27008_get_int_time_us(data);
if (ret < 0)
return ret;
*val = 0;
*val2 = ret;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
/* Called if the new scale could not be supported with existing int-time */
static int bu27008_try_find_new_time_gain(struct bu27008_data *data, int val,
int val2, int *gain_sel)
{
int i, ret, new_time_sel;
for (i = 0; i < data->gts.num_itime; i++) {
new_time_sel = data->gts.itime_table[i].sel;
ret = iio_gts_find_gain_sel_for_scale_using_time(&data->gts,
new_time_sel, val, val2, gain_sel);
if (!ret)
break;
}
if (i == data->gts.num_itime) {
dev_err(data->dev, "Can't support scale %u %u\n", val, val2);
return -EINVAL;
}
return bu27008_set_int_time_sel(data, new_time_sel);
}
static int bu27008_set_scale(struct bu27008_data *data,
struct iio_chan_spec const *chan,
int val, int val2)
{
int ret, gain_sel, time_sel;
if (chan->scan_index == BU27008_IR)
return -EINVAL;
mutex_lock(&data->mutex);
ret = bu27008_get_int_time_sel(data, &time_sel);
if (ret < 0)
goto unlock_out;
ret = iio_gts_find_gain_sel_for_scale_using_time(&data->gts, time_sel,
val, val2, &gain_sel);
if (ret) {
ret = bu27008_try_find_new_time_gain(data, val, val2, &gain_sel);
if (ret)
goto unlock_out;
}
ret = bu27008_write_gain_sel(data, gain_sel);
unlock_out:
mutex_unlock(&data->mutex);
return ret;
}
static int bu27008_write_raw_get_fmt(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
long mask)
{
switch (mask) {
case IIO_CHAN_INFO_SCALE:
return IIO_VAL_INT_PLUS_NANO;
case IIO_CHAN_INFO_INT_TIME:
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int bu27008_write_raw(struct iio_dev *idev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct bu27008_data *data = iio_priv(idev);
int ret;
/*
* Do not allow changing scale when measurement is ongoing as doing so
* could make values in the buffer inconsistent.
*/
ret = iio_device_claim_direct_mode(idev);
if (ret)
return ret;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
ret = bu27008_set_scale(data, chan, val, val2);
break;
case IIO_CHAN_INFO_INT_TIME:
if (val) {
ret = -EINVAL;
break;
}
ret = bu27008_try_set_int_time(data, val2);
break;
default:
ret = -EINVAL;
break;
}
iio_device_release_direct_mode(idev);
return ret;
}
static int bu27008_read_avail(struct iio_dev *idev,
struct iio_chan_spec const *chan, const int **vals,
int *type, int *length, long mask)
{
struct bu27008_data *data = iio_priv(idev);
switch (mask) {
case IIO_CHAN_INFO_INT_TIME:
return iio_gts_avail_times(&data->gts, vals, type, length);
case IIO_CHAN_INFO_SCALE:
if (chan->channel2 == IIO_MOD_LIGHT_IR)
return iio_gts_all_avail_scales(&data->gts_ir, vals,
type, length);
return iio_gts_all_avail_scales(&data->gts, vals, type, length);
default:
return -EINVAL;
}
}
static int bu27008_update_scan_mode(struct iio_dev *idev,
const unsigned long *scan_mask)
{
struct bu27008_data *data = iio_priv(idev);
int chan_sel;
/* Configure channel selection */
if (test_bit(BU27008_BLUE, idev->active_scan_mask)) {
if (test_bit(BU27008_CLEAR, idev->active_scan_mask))
chan_sel = BU27008_BLUE2_CLEAR3;
else
chan_sel = BU27008_BLUE2_IR3;
} else {
chan_sel = BU27008_CLEAR2_IR3;
}
chan_sel = FIELD_PREP(BU27008_MASK_CHAN_SEL, chan_sel);
return regmap_update_bits(data->regmap, BU27008_REG_MODE_CONTROL3,
BU27008_MASK_CHAN_SEL, chan_sel);
}
static const struct iio_info bu27008_info = {
.read_raw = &bu27008_read_raw,
.write_raw = &bu27008_write_raw,
.write_raw_get_fmt = &bu27008_write_raw_get_fmt,
.read_avail = &bu27008_read_avail,
.update_scan_mode = bu27008_update_scan_mode,
.validate_trigger = iio_validate_own_trigger,
};
static int bu27008_chip_init(struct bu27008_data *data)
{
int ret;
ret = regmap_write_bits(data->regmap, BU27008_REG_SYSTEM_CONTROL,
BU27008_MASK_SW_RESET, BU27008_MASK_SW_RESET);
if (ret)
return dev_err_probe(data->dev, ret, "Sensor reset failed\n");
/*
* The data-sheet does not tell how long performing the IC reset takes.
* However, the data-sheet says the minimum time it takes the IC to be
* able to take inputs after power is applied, is 100 uS. I'd assume
* > 1 mS is enough.
*/
msleep(1);
ret = regmap_reinit_cache(data->regmap, &bu27008_regmap);
if (ret)
dev_err(data->dev, "Failed to reinit reg cache\n");
return ret;
}
static int bu27008_set_drdy_irq(struct bu27008_data *data, int state)
{
return regmap_update_bits(data->regmap, BU27008_REG_MODE_CONTROL3,
BU27008_MASK_INT_EN, state);
}
static int bu27008_trigger_set_state(struct iio_trigger *trig,
bool state)
{
struct bu27008_data *data = iio_trigger_get_drvdata(trig);
int ret;
if (state)
ret = bu27008_set_drdy_irq(data, BU27008_INT_EN);
else
ret = bu27008_set_drdy_irq(data, BU27008_INT_DIS);
if (ret)
dev_err(data->dev, "Failed to set trigger state\n");
return ret;
}
static void bu27008_trigger_reenable(struct iio_trigger *trig)
{
struct bu27008_data *data = iio_trigger_get_drvdata(trig);
enable_irq(data->irq);
}
static const struct iio_trigger_ops bu27008_trigger_ops = {
.set_trigger_state = bu27008_trigger_set_state,
.reenable = bu27008_trigger_reenable,
};
static irqreturn_t bu27008_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *idev = pf->indio_dev;
struct bu27008_data *data = iio_priv(idev);
struct {
__le16 chan[BU27008_NUM_HW_CHANS];
s64 ts __aligned(8);
} raw;
int ret, dummy;
memset(&raw, 0, sizeof(raw));
/*
* After some measurements, it seems reading the
* BU27008_REG_MODE_CONTROL3 debounces the IRQ line
*/
ret = regmap_read(data->regmap, BU27008_REG_MODE_CONTROL3, &dummy);
if (ret < 0)
goto err_read;
ret = regmap_bulk_read(data->regmap, BU27008_REG_DATA0_LO, &raw.chan,
sizeof(raw.chan));
if (ret < 0)
goto err_read;
iio_push_to_buffers_with_timestamp(idev, &raw, pf->timestamp);
err_read:
iio_trigger_notify_done(idev->trig);
return IRQ_HANDLED;
}
static int bu27008_buffer_preenable(struct iio_dev *idev)
{
struct bu27008_data *data = iio_priv(idev);
return bu27008_meas_set(data, BU27008_MEAS_EN);
}
static int bu27008_buffer_postdisable(struct iio_dev *idev)
{
struct bu27008_data *data = iio_priv(idev);
return bu27008_meas_set(data, BU27008_MEAS_DIS);
}
static const struct iio_buffer_setup_ops bu27008_buffer_ops = {
.preenable = bu27008_buffer_preenable,
.postdisable = bu27008_buffer_postdisable,
};
static irqreturn_t bu27008_data_rdy_poll(int irq, void *private)
{
/*
* The BU27008 keeps IRQ asserted until we read the VALID bit from
* a register. We need to keep the IRQ disabled until then.
*/
disable_irq_nosync(irq);
iio_trigger_poll(private);
return IRQ_HANDLED;
}
static int bu27008_setup_trigger(struct bu27008_data *data, struct iio_dev *idev)
{
struct iio_trigger *itrig;
char *name;
int ret;
ret = devm_iio_triggered_buffer_setup(data->dev, idev,
&iio_pollfunc_store_time,
bu27008_trigger_handler,
&bu27008_buffer_ops);
if (ret)
return dev_err_probe(data->dev, ret,
"iio_triggered_buffer_setup_ext FAIL\n");
itrig = devm_iio_trigger_alloc(data->dev, "%sdata-rdy-dev%d",
idev->name, iio_device_id(idev));
if (!itrig)
return -ENOMEM;
data->trig = itrig;
itrig->ops = &bu27008_trigger_ops;
iio_trigger_set_drvdata(itrig, data);
name = devm_kasprintf(data->dev, GFP_KERNEL, "%s-bu27008",
dev_name(data->dev));
ret = devm_request_irq(data->dev, data->irq,
&bu27008_data_rdy_poll,
0, name, itrig);
if (ret)
return dev_err_probe(data->dev, ret, "Could not request IRQ\n");
ret = devm_iio_trigger_register(data->dev, itrig);
if (ret)
return dev_err_probe(data->dev, ret,
"Trigger registration failed\n");
/* set default trigger */
idev->trig = iio_trigger_get(itrig);
return 0;
}
static int bu27008_probe(struct i2c_client *i2c)
{
struct device *dev = &i2c->dev;
struct bu27008_data *data;
struct regmap *regmap;
unsigned int part_id, reg;
struct iio_dev *idev;
int ret;
regmap = devm_regmap_init_i2c(i2c, &bu27008_regmap);
if (IS_ERR(regmap))
return dev_err_probe(dev, PTR_ERR(regmap),
"Failed to initialize Regmap\n");
idev = devm_iio_device_alloc(dev, sizeof(*data));
if (!idev)
return -ENOMEM;
ret = devm_regulator_get_enable(dev, "vdd");
if (ret)
return dev_err_probe(dev, ret, "Failed to get regulator\n");
data = iio_priv(idev);
ret = regmap_read(regmap, BU27008_REG_SYSTEM_CONTROL, &reg);
if (ret)
return dev_err_probe(dev, ret, "Failed to access sensor\n");
part_id = FIELD_GET(BU27008_MASK_PART_ID, reg);
if (part_id != BU27008_ID)
dev_warn(dev, "unknown device 0x%x\n", part_id);
ret = devm_iio_init_iio_gts(dev, BU27008_SCALE_1X, 0, bu27008_gains,
ARRAY_SIZE(bu27008_gains), bu27008_itimes,
ARRAY_SIZE(bu27008_itimes), &data->gts);
if (ret)
return ret;
ret = devm_iio_init_iio_gts(dev, BU27008_SCALE_1X, 0, bu27008_gains_ir,
ARRAY_SIZE(bu27008_gains_ir), bu27008_itimes,
ARRAY_SIZE(bu27008_itimes), &data->gts_ir);
if (ret)
return ret;
mutex_init(&data->mutex);
data->regmap = regmap;
data->dev = dev;
data->irq = i2c->irq;
idev->channels = bu27008_channels;
idev->num_channels = ARRAY_SIZE(bu27008_channels);
idev->name = "bu27008";
idev->info = &bu27008_info;
idev->modes = INDIO_DIRECT_MODE;
idev->available_scan_masks = bu27008_scan_masks;
ret = bu27008_chip_init(data);
if (ret)
return ret;
if (i2c->irq) {
ret = bu27008_setup_trigger(data, idev);
if (ret)
return ret;
} else {
dev_info(dev, "No IRQ, buffered mode disabled\n");
}
ret = devm_iio_device_register(dev, idev);
if (ret)
return dev_err_probe(dev, ret,
"Unable to register iio device\n");
return 0;
}
static const struct of_device_id bu27008_of_match[] = {
{ .compatible = "rohm,bu27008" },
{ }
};
MODULE_DEVICE_TABLE(of, bu27008_of_match);
static struct i2c_driver bu27008_i2c_driver = {
.driver = {
.name = "bu27008",
.of_match_table = bu27008_of_match,
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe = bu27008_probe,
};
module_i2c_driver(bu27008_i2c_driver);
MODULE_DESCRIPTION("ROHM BU27008 colour sensor driver");
MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(IIO_GTS_HELPER);