// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2021 Google LLC.
*
* Common part of most Semtech SAR sensor.
*/
#include <linux/bitops.h>
#include <linux/byteorder/generic.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/irqreturn.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <vdso/bits.h>
#include <linux/iio/buffer.h>
#include <linux/iio/events.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
#include "sx_common.h"
/* All Semtech SAR sensors have IRQ bit in the same order. */
#define SX_COMMON_CONVDONE_IRQ BIT(0)
#define SX_COMMON_FAR_IRQ BIT(2)
#define SX_COMMON_CLOSE_IRQ BIT(3)
const struct iio_event_spec sx_common_events[3] = {
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_RISING,
.mask_shared_by_all = BIT(IIO_EV_INFO_PERIOD),
},
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_FALLING,
.mask_shared_by_all = BIT(IIO_EV_INFO_PERIOD),
},
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_EITHER,
.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
BIT(IIO_EV_INFO_HYSTERESIS) |
BIT(IIO_EV_INFO_VALUE),
},
};
EXPORT_SYMBOL_NS_GPL(sx_common_events, SEMTECH_PROX);
static irqreturn_t sx_common_irq_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct sx_common_data *data = iio_priv(indio_dev);
if (data->trigger_enabled)
iio_trigger_poll(data->trig);
/*
* Even if no event is enabled, we need to wake the thread to clear the
* interrupt state by reading SX_COMMON_REG_IRQ_SRC.
* It is not possible to do that here because regmap_read takes a mutex.
*/
return IRQ_WAKE_THREAD;
}
static void sx_common_push_events(struct iio_dev *indio_dev)
{
int ret;
unsigned int val, chan;
struct sx_common_data *data = iio_priv(indio_dev);
s64 timestamp = iio_get_time_ns(indio_dev);
unsigned long prox_changed;
/* Read proximity state on all channels */
ret = regmap_read(data->regmap, data->chip_info->reg_stat, &val);
if (ret) {
dev_err(&data->client->dev, "i2c transfer error in irq\n");
return;
}
val >>= data->chip_info->stat_offset;
/*
* Only iterate over channels with changes on proximity status that have
* events enabled.
*/
prox_changed = (data->chan_prox_stat ^ val) & data->chan_event;
for_each_set_bit(chan, &prox_changed, data->chip_info->num_channels) {
int dir;
u64 ev;
dir = (val & BIT(chan)) ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
IIO_EV_TYPE_THRESH, dir);
iio_push_event(indio_dev, ev, timestamp);
}
data->chan_prox_stat = val;
}
static int sx_common_enable_irq(struct sx_common_data *data, unsigned int irq)
{
if (!data->client->irq)
return 0;
return regmap_set_bits(data->regmap, data->chip_info->reg_irq_msk,
irq << data->chip_info->irq_msk_offset);
}
static int sx_common_disable_irq(struct sx_common_data *data, unsigned int irq)
{
if (!data->client->irq)
return 0;
return regmap_clear_bits(data->regmap, data->chip_info->reg_irq_msk,
irq << data->chip_info->irq_msk_offset);
}
static int sx_common_update_chan_en(struct sx_common_data *data,
unsigned long chan_read,
unsigned long chan_event)
{
int ret;
unsigned long channels = chan_read | chan_event;
if ((data->chan_read | data->chan_event) != channels) {
ret = regmap_update_bits(data->regmap,
data->chip_info->reg_enable_chan,
data->chip_info->mask_enable_chan,
channels);
if (ret)
return ret;
}
data->chan_read = chan_read;
data->chan_event = chan_event;
return 0;
}
static int sx_common_get_read_channel(struct sx_common_data *data, int channel)
{
return sx_common_update_chan_en(data, data->chan_read | BIT(channel),
data->chan_event);
}
static int sx_common_put_read_channel(struct sx_common_data *data, int channel)
{
return sx_common_update_chan_en(data, data->chan_read & ~BIT(channel),
data->chan_event);
}
static int sx_common_get_event_channel(struct sx_common_data *data, int channel)
{
return sx_common_update_chan_en(data, data->chan_read,
data->chan_event | BIT(channel));
}
static int sx_common_put_event_channel(struct sx_common_data *data, int channel)
{
return sx_common_update_chan_en(data, data->chan_read,
data->chan_event & ~BIT(channel));
}
/**
* sx_common_read_proximity() - Read raw proximity value.
* @data: Internal data
* @chan: Channel to read
* @val: pointer to return read value.
*
* Request a conversion, wait for the sensor to be ready and
* return the raw proximity value.
*/
int sx_common_read_proximity(struct sx_common_data *data,
const struct iio_chan_spec *chan, int *val)
{
int ret;
__be16 rawval;
mutex_lock(&data->mutex);
ret = sx_common_get_read_channel(data, chan->channel);
if (ret)
goto out;
ret = sx_common_enable_irq(data, SX_COMMON_CONVDONE_IRQ);
if (ret)
goto out_put_channel;
mutex_unlock(&data->mutex);
if (data->client->irq) {
ret = wait_for_completion_interruptible(&data->completion);
reinit_completion(&data->completion);
} else {
ret = data->chip_info->ops.wait_for_sample(data);
}
mutex_lock(&data->mutex);
if (ret)
goto out_disable_irq;
ret = data->chip_info->ops.read_prox_data(data, chan, &rawval);
if (ret)
goto out_disable_irq;
*val = sign_extend32(be16_to_cpu(rawval), chan->scan_type.realbits - 1);
ret = sx_common_disable_irq(data, SX_COMMON_CONVDONE_IRQ);
if (ret)
goto out_put_channel;
ret = sx_common_put_read_channel(data, chan->channel);
if (ret)
goto out;
mutex_unlock(&data->mutex);
return IIO_VAL_INT;
out_disable_irq:
sx_common_disable_irq(data, SX_COMMON_CONVDONE_IRQ);
out_put_channel:
sx_common_put_read_channel(data, chan->channel);
out:
mutex_unlock(&data->mutex);
return ret;
}
EXPORT_SYMBOL_NS_GPL(sx_common_read_proximity, SEMTECH_PROX);
/**
* sx_common_read_event_config() - Configure event setting.
* @indio_dev: iio device object
* @chan: Channel to read
* @type: Type of event (unused)
* @dir: Direction of event (unused)
*
* return if the given channel is used for event gathering.
*/
int sx_common_read_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir)
{
struct sx_common_data *data = iio_priv(indio_dev);
return !!(data->chan_event & BIT(chan->channel));
}
EXPORT_SYMBOL_NS_GPL(sx_common_read_event_config, SEMTECH_PROX);
/**
* sx_common_write_event_config() - Configure event setting.
* @indio_dev: iio device object
* @chan: Channel to enable
* @type: Type of event (unused)
* @dir: Direction of event (unused)
* @state: State of the event.
*
* Enable/Disable event on a given channel.
*/
int sx_common_write_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir, int state)
{
struct sx_common_data *data = iio_priv(indio_dev);
unsigned int eventirq = SX_COMMON_FAR_IRQ | SX_COMMON_CLOSE_IRQ;
int ret;
/* If the state hasn't changed, there's nothing to do. */
if (!!(data->chan_event & BIT(chan->channel)) == state)
return 0;
mutex_lock(&data->mutex);
if (state) {
ret = sx_common_get_event_channel(data, chan->channel);
if (ret)
goto out_unlock;
if (!(data->chan_event & ~BIT(chan->channel))) {
ret = sx_common_enable_irq(data, eventirq);
if (ret)
sx_common_put_event_channel(data, chan->channel);
}
} else {
ret = sx_common_put_event_channel(data, chan->channel);
if (ret)
goto out_unlock;
if (!data->chan_event) {
ret = sx_common_disable_irq(data, eventirq);
if (ret)
sx_common_get_event_channel(data, chan->channel);
}
}
out_unlock:
mutex_unlock(&data->mutex);
return ret;
}
EXPORT_SYMBOL_NS_GPL(sx_common_write_event_config, SEMTECH_PROX);
static int sx_common_set_trigger_state(struct iio_trigger *trig, bool state)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct sx_common_data *data = iio_priv(indio_dev);
int ret = 0;
mutex_lock(&data->mutex);
if (state)
ret = sx_common_enable_irq(data, SX_COMMON_CONVDONE_IRQ);
else if (!data->chan_read)
ret = sx_common_disable_irq(data, SX_COMMON_CONVDONE_IRQ);
if (ret)
goto out;
data->trigger_enabled = state;
out:
mutex_unlock(&data->mutex);
return ret;
}
static const struct iio_trigger_ops sx_common_trigger_ops = {
.set_trigger_state = sx_common_set_trigger_state,
};
static irqreturn_t sx_common_irq_thread_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct sx_common_data *data = iio_priv(indio_dev);
int ret;
unsigned int val;
mutex_lock(&data->mutex);
ret = regmap_read(data->regmap, SX_COMMON_REG_IRQ_SRC, &val);
if (ret) {
dev_err(&data->client->dev, "i2c transfer error in irq\n");
goto out;
}
if (val & ((SX_COMMON_FAR_IRQ | SX_COMMON_CLOSE_IRQ) << data->chip_info->irq_msk_offset))
sx_common_push_events(indio_dev);
if (val & (SX_COMMON_CONVDONE_IRQ << data->chip_info->irq_msk_offset))
complete(&data->completion);
out:
mutex_unlock(&data->mutex);
return IRQ_HANDLED;
}
static irqreturn_t sx_common_trigger_handler(int irq, void *private)
{
struct iio_poll_func *pf = private;
struct iio_dev *indio_dev = pf->indio_dev;
struct sx_common_data *data = iio_priv(indio_dev);
__be16 val;
int bit, ret, i = 0;
mutex_lock(&data->mutex);
iio_for_each_active_channel(indio_dev, bit) {
ret = data->chip_info->ops.read_prox_data(data,
&indio_dev->channels[bit],
&val);
if (ret)
goto out;
data->buffer.channels[i++] = val;
}
iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer,
pf->timestamp);
out:
mutex_unlock(&data->mutex);
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int sx_common_buffer_preenable(struct iio_dev *indio_dev)
{
struct sx_common_data *data = iio_priv(indio_dev);
unsigned long channels = 0;
int bit, ret;
mutex_lock(&data->mutex);
iio_for_each_active_channel(indio_dev, bit)
__set_bit(indio_dev->channels[bit].channel, &channels);
ret = sx_common_update_chan_en(data, channels, data->chan_event);
mutex_unlock(&data->mutex);
return ret;
}
static int sx_common_buffer_postdisable(struct iio_dev *indio_dev)
{
struct sx_common_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->mutex);
ret = sx_common_update_chan_en(data, 0, data->chan_event);
mutex_unlock(&data->mutex);
return ret;
}
static const struct iio_buffer_setup_ops sx_common_buffer_setup_ops = {
.preenable = sx_common_buffer_preenable,
.postdisable = sx_common_buffer_postdisable,
};
void sx_common_get_raw_register_config(struct device *dev,
struct sx_common_reg_default *reg_def)
{
#ifdef CONFIG_ACPI
struct acpi_device *adev = ACPI_COMPANION(dev);
u32 raw = 0, ret;
char prop[80];
if (!reg_def->property || !adev)
return;
snprintf(prop, ARRAY_SIZE(prop), "%s,reg_%s", acpi_device_hid(adev), reg_def->property);
ret = device_property_read_u32(dev, prop, &raw);
if (ret)
return;
reg_def->def = raw;
#endif
}
EXPORT_SYMBOL_NS_GPL(sx_common_get_raw_register_config, SEMTECH_PROX);
#define SX_COMMON_SOFT_RESET 0xde
static int sx_common_init_device(struct device *dev, struct iio_dev *indio_dev)
{
struct sx_common_data *data = iio_priv(indio_dev);
struct sx_common_reg_default tmp;
const struct sx_common_reg_default *initval;
int ret;
unsigned int i, val;
ret = regmap_write(data->regmap, data->chip_info->reg_reset,
SX_COMMON_SOFT_RESET);
if (ret)
return ret;
usleep_range(1000, 2000); /* power-up time is ~1ms. */
/* Clear reset interrupt state by reading SX_COMMON_REG_IRQ_SRC. */
ret = regmap_read(data->regmap, SX_COMMON_REG_IRQ_SRC, &val);
if (ret)
return ret;
/* Program defaults from constant or BIOS. */
for (i = 0; i < data->chip_info->num_default_regs; i++) {
initval = data->chip_info->ops.get_default_reg(dev, i, &tmp);
ret = regmap_write(data->regmap, initval->reg, initval->def);
if (ret)
return ret;
}
return data->chip_info->ops.init_compensation(indio_dev);
}
/**
* sx_common_probe() - Common setup for Semtech SAR sensor
* @client: I2C client object
* @chip_info: Semtech sensor chip information.
* @regmap_config: Sensor registers map configuration.
*/
int sx_common_probe(struct i2c_client *client,
const struct sx_common_chip_info *chip_info,
const struct regmap_config *regmap_config)
{
static const char * const regulator_names[] = { "vdd", "svdd" };
struct device *dev = &client->dev;
struct iio_dev *indio_dev;
struct sx_common_data *data;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
data->chip_info = chip_info;
data->client = client;
mutex_init(&data->mutex);
init_completion(&data->completion);
data->regmap = devm_regmap_init_i2c(client, regmap_config);
if (IS_ERR(data->regmap))
return dev_err_probe(dev, PTR_ERR(data->regmap),
"Could init register map\n");
ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(regulator_names),
regulator_names);
if (ret)
return dev_err_probe(dev, ret, "Unable to get regulators\n");
/* Must wait for Tpor time after initial power up */
usleep_range(1000, 1100);
ret = data->chip_info->ops.check_whoami(dev, indio_dev);
if (ret)
return dev_err_probe(dev, ret, "error reading WHOAMI\n");
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = data->chip_info->iio_channels;
indio_dev->num_channels = data->chip_info->num_iio_channels;
indio_dev->info = &data->chip_info->iio_info;
i2c_set_clientdata(client, indio_dev);
ret = sx_common_init_device(dev, indio_dev);
if (ret)
return dev_err_probe(dev, ret, "Unable to initialize sensor\n");
if (client->irq) {
ret = devm_request_threaded_irq(dev, client->irq,
sx_common_irq_handler,
sx_common_irq_thread_handler,
IRQF_ONESHOT,
"sx_event", indio_dev);
if (ret)
return dev_err_probe(dev, ret, "No IRQ\n");
data->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
indio_dev->name,
iio_device_id(indio_dev));
if (!data->trig)
return -ENOMEM;
data->trig->ops = &sx_common_trigger_ops;
iio_trigger_set_drvdata(data->trig, indio_dev);
ret = devm_iio_trigger_register(dev, data->trig);
if (ret)
return ret;
}
ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
iio_pollfunc_store_time,
sx_common_trigger_handler,
&sx_common_buffer_setup_ops);
if (ret)
return ret;
return devm_iio_device_register(dev, indio_dev);
}
EXPORT_SYMBOL_NS_GPL(sx_common_probe, SEMTECH_PROX);
MODULE_AUTHOR("Gwendal Grignou <[email protected]>");
MODULE_DESCRIPTION("Common functions and structures for Semtech sensor");
MODULE_LICENSE("GPL v2");
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