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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright 2021 Google LLC.4 *5 * Common part of most Semtech SAR sensor.6 */7 8#include <linux/bitops.h>9#include <linux/byteorder/generic.h>10#include <linux/delay.h>11#include <linux/device.h>12#include <linux/err.h>13#include <linux/export.h>14#include <linux/interrupt.h>15#include <linux/irqreturn.h>16#include <linux/i2c.h>17#include <linux/kernel.h>18#include <linux/module.h>19#include <linux/regmap.h>20#include <linux/regulator/consumer.h>21#include <vdso/bits.h>22 23#include <linux/iio/buffer.h>24#include <linux/iio/events.h>25#include <linux/iio/iio.h>26#include <linux/iio/trigger.h>27#include <linux/iio/triggered_buffer.h>28#include <linux/iio/trigger_consumer.h>29 30#include "sx_common.h"31 32/* All Semtech SAR sensors have IRQ bit in the same order. */33#define SX_COMMON_CONVDONE_IRQ BIT(0)34#define SX_COMMON_FAR_IRQ BIT(2)35#define SX_COMMON_CLOSE_IRQ BIT(3)36 37const struct iio_event_spec sx_common_events[3] = {38 {39 .type = IIO_EV_TYPE_THRESH,40 .dir = IIO_EV_DIR_RISING,41 .mask_shared_by_all = BIT(IIO_EV_INFO_PERIOD),42 },43 {44 .type = IIO_EV_TYPE_THRESH,45 .dir = IIO_EV_DIR_FALLING,46 .mask_shared_by_all = BIT(IIO_EV_INFO_PERIOD),47 },48 {49 .type = IIO_EV_TYPE_THRESH,50 .dir = IIO_EV_DIR_EITHER,51 .mask_separate = BIT(IIO_EV_INFO_ENABLE) |52 BIT(IIO_EV_INFO_HYSTERESIS) |53 BIT(IIO_EV_INFO_VALUE),54 },55};56EXPORT_SYMBOL_NS_GPL(sx_common_events, SEMTECH_PROX);57 58static irqreturn_t sx_common_irq_handler(int irq, void *private)59{60 struct iio_dev *indio_dev = private;61 struct sx_common_data *data = iio_priv(indio_dev);62 63 if (data->trigger_enabled)64 iio_trigger_poll(data->trig);65 66 /*67 * Even if no event is enabled, we need to wake the thread to clear the68 * interrupt state by reading SX_COMMON_REG_IRQ_SRC.69 * It is not possible to do that here because regmap_read takes a mutex.70 */71 return IRQ_WAKE_THREAD;72}73 74static void sx_common_push_events(struct iio_dev *indio_dev)75{76 int ret;77 unsigned int val, chan;78 struct sx_common_data *data = iio_priv(indio_dev);79 s64 timestamp = iio_get_time_ns(indio_dev);80 unsigned long prox_changed;81 82 /* Read proximity state on all channels */83 ret = regmap_read(data->regmap, data->chip_info->reg_stat, &val);84 if (ret) {85 dev_err(&data->client->dev, "i2c transfer error in irq\n");86 return;87 }88 89 val >>= data->chip_info->stat_offset;90 91 /*92 * Only iterate over channels with changes on proximity status that have93 * events enabled.94 */95 prox_changed = (data->chan_prox_stat ^ val) & data->chan_event;96 97 for_each_set_bit(chan, &prox_changed, data->chip_info->num_channels) {98 int dir;99 u64 ev;100 101 dir = (val & BIT(chan)) ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;102 ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,103 IIO_EV_TYPE_THRESH, dir);104 105 iio_push_event(indio_dev, ev, timestamp);106 }107 data->chan_prox_stat = val;108}109 110static int sx_common_enable_irq(struct sx_common_data *data, unsigned int irq)111{112 if (!data->client->irq)113 return 0;114 return regmap_set_bits(data->regmap, data->chip_info->reg_irq_msk,115 irq << data->chip_info->irq_msk_offset);116}117 118static int sx_common_disable_irq(struct sx_common_data *data, unsigned int irq)119{120 if (!data->client->irq)121 return 0;122 return regmap_clear_bits(data->regmap, data->chip_info->reg_irq_msk,123 irq << data->chip_info->irq_msk_offset);124}125 126static int sx_common_update_chan_en(struct sx_common_data *data,127 unsigned long chan_read,128 unsigned long chan_event)129{130 int ret;131 unsigned long channels = chan_read | chan_event;132 133 if ((data->chan_read | data->chan_event) != channels) {134 ret = regmap_update_bits(data->regmap,135 data->chip_info->reg_enable_chan,136 data->chip_info->mask_enable_chan,137 channels);138 if (ret)139 return ret;140 }141 data->chan_read = chan_read;142 data->chan_event = chan_event;143 return 0;144}145 146static int sx_common_get_read_channel(struct sx_common_data *data, int channel)147{148 return sx_common_update_chan_en(data, data->chan_read | BIT(channel),149 data->chan_event);150}151 152static int sx_common_put_read_channel(struct sx_common_data *data, int channel)153{154 return sx_common_update_chan_en(data, data->chan_read & ~BIT(channel),155 data->chan_event);156}157 158static int sx_common_get_event_channel(struct sx_common_data *data, int channel)159{160 return sx_common_update_chan_en(data, data->chan_read,161 data->chan_event | BIT(channel));162}163 164static int sx_common_put_event_channel(struct sx_common_data *data, int channel)165{166 return sx_common_update_chan_en(data, data->chan_read,167 data->chan_event & ~BIT(channel));168}169 170/**171 * sx_common_read_proximity() - Read raw proximity value.172 * @data: Internal data173 * @chan: Channel to read174 * @val: pointer to return read value.175 *176 * Request a conversion, wait for the sensor to be ready and177 * return the raw proximity value.178 */179int sx_common_read_proximity(struct sx_common_data *data,180 const struct iio_chan_spec *chan, int *val)181{182 int ret;183 __be16 rawval;184 185 mutex_lock(&data->mutex);186 187 ret = sx_common_get_read_channel(data, chan->channel);188 if (ret)189 goto out;190 191 ret = sx_common_enable_irq(data, SX_COMMON_CONVDONE_IRQ);192 if (ret)193 goto out_put_channel;194 195 mutex_unlock(&data->mutex);196 197 if (data->client->irq) {198 ret = wait_for_completion_interruptible(&data->completion);199 reinit_completion(&data->completion);200 } else {201 ret = data->chip_info->ops.wait_for_sample(data);202 }203 204 mutex_lock(&data->mutex);205 206 if (ret)207 goto out_disable_irq;208 209 ret = data->chip_info->ops.read_prox_data(data, chan, &rawval);210 if (ret)211 goto out_disable_irq;212 213 *val = sign_extend32(be16_to_cpu(rawval), chan->scan_type.realbits - 1);214 215 ret = sx_common_disable_irq(data, SX_COMMON_CONVDONE_IRQ);216 if (ret)217 goto out_put_channel;218 219 ret = sx_common_put_read_channel(data, chan->channel);220 if (ret)221 goto out;222 223 mutex_unlock(&data->mutex);224 225 return IIO_VAL_INT;226 227out_disable_irq:228 sx_common_disable_irq(data, SX_COMMON_CONVDONE_IRQ);229out_put_channel:230 sx_common_put_read_channel(data, chan->channel);231out:232 mutex_unlock(&data->mutex);233 234 return ret;235}236EXPORT_SYMBOL_NS_GPL(sx_common_read_proximity, SEMTECH_PROX);237 238/**239 * sx_common_read_event_config() - Configure event setting.240 * @indio_dev: iio device object241 * @chan: Channel to read242 * @type: Type of event (unused)243 * @dir: Direction of event (unused)244 *245 * return if the given channel is used for event gathering.246 */247int sx_common_read_event_config(struct iio_dev *indio_dev,248 const struct iio_chan_spec *chan,249 enum iio_event_type type,250 enum iio_event_direction dir)251{252 struct sx_common_data *data = iio_priv(indio_dev);253 254 return !!(data->chan_event & BIT(chan->channel));255}256EXPORT_SYMBOL_NS_GPL(sx_common_read_event_config, SEMTECH_PROX);257 258/**259 * sx_common_write_event_config() - Configure event setting.260 * @indio_dev: iio device object261 * @chan: Channel to enable262 * @type: Type of event (unused)263 * @dir: Direction of event (unused)264 * @state: State of the event.265 *266 * Enable/Disable event on a given channel.267 */268int sx_common_write_event_config(struct iio_dev *indio_dev,269 const struct iio_chan_spec *chan,270 enum iio_event_type type,271 enum iio_event_direction dir, int state)272{273 struct sx_common_data *data = iio_priv(indio_dev);274 unsigned int eventirq = SX_COMMON_FAR_IRQ | SX_COMMON_CLOSE_IRQ;275 int ret;276 277 /* If the state hasn't changed, there's nothing to do. */278 if (!!(data->chan_event & BIT(chan->channel)) == state)279 return 0;280 281 mutex_lock(&data->mutex);282 if (state) {283 ret = sx_common_get_event_channel(data, chan->channel);284 if (ret)285 goto out_unlock;286 if (!(data->chan_event & ~BIT(chan->channel))) {287 ret = sx_common_enable_irq(data, eventirq);288 if (ret)289 sx_common_put_event_channel(data, chan->channel);290 }291 } else {292 ret = sx_common_put_event_channel(data, chan->channel);293 if (ret)294 goto out_unlock;295 if (!data->chan_event) {296 ret = sx_common_disable_irq(data, eventirq);297 if (ret)298 sx_common_get_event_channel(data, chan->channel);299 }300 }301 302out_unlock:303 mutex_unlock(&data->mutex);304 return ret;305}306EXPORT_SYMBOL_NS_GPL(sx_common_write_event_config, SEMTECH_PROX);307 308static int sx_common_set_trigger_state(struct iio_trigger *trig, bool state)309{310 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);311 struct sx_common_data *data = iio_priv(indio_dev);312 int ret = 0;313 314 mutex_lock(&data->mutex);315 316 if (state)317 ret = sx_common_enable_irq(data, SX_COMMON_CONVDONE_IRQ);318 else if (!data->chan_read)319 ret = sx_common_disable_irq(data, SX_COMMON_CONVDONE_IRQ);320 if (ret)321 goto out;322 323 data->trigger_enabled = state;324 325out:326 mutex_unlock(&data->mutex);327 328 return ret;329}330 331static const struct iio_trigger_ops sx_common_trigger_ops = {332 .set_trigger_state = sx_common_set_trigger_state,333};334 335static irqreturn_t sx_common_irq_thread_handler(int irq, void *private)336{337 struct iio_dev *indio_dev = private;338 struct sx_common_data *data = iio_priv(indio_dev);339 int ret;340 unsigned int val;341 342 mutex_lock(&data->mutex);343 344 ret = regmap_read(data->regmap, SX_COMMON_REG_IRQ_SRC, &val);345 if (ret) {346 dev_err(&data->client->dev, "i2c transfer error in irq\n");347 goto out;348 }349 350 if (val & ((SX_COMMON_FAR_IRQ | SX_COMMON_CLOSE_IRQ) << data->chip_info->irq_msk_offset))351 sx_common_push_events(indio_dev);352 353 if (val & (SX_COMMON_CONVDONE_IRQ << data->chip_info->irq_msk_offset))354 complete(&data->completion);355 356out:357 mutex_unlock(&data->mutex);358 359 return IRQ_HANDLED;360}361 362static irqreturn_t sx_common_trigger_handler(int irq, void *private)363{364 struct iio_poll_func *pf = private;365 struct iio_dev *indio_dev = pf->indio_dev;366 struct sx_common_data *data = iio_priv(indio_dev);367 __be16 val;368 int bit, ret, i = 0;369 370 mutex_lock(&data->mutex);371 372 iio_for_each_active_channel(indio_dev, bit) {373 ret = data->chip_info->ops.read_prox_data(data,374 &indio_dev->channels[bit],375 &val);376 if (ret)377 goto out;378 379 data->buffer.channels[i++] = val;380 }381 382 iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer,383 pf->timestamp);384 385out:386 mutex_unlock(&data->mutex);387 388 iio_trigger_notify_done(indio_dev->trig);389 390 return IRQ_HANDLED;391}392 393static int sx_common_buffer_preenable(struct iio_dev *indio_dev)394{395 struct sx_common_data *data = iio_priv(indio_dev);396 unsigned long channels = 0;397 int bit, ret;398 399 mutex_lock(&data->mutex);400 iio_for_each_active_channel(indio_dev, bit)401 __set_bit(indio_dev->channels[bit].channel, &channels);402 403 ret = sx_common_update_chan_en(data, channels, data->chan_event);404 mutex_unlock(&data->mutex);405 return ret;406}407 408static int sx_common_buffer_postdisable(struct iio_dev *indio_dev)409{410 struct sx_common_data *data = iio_priv(indio_dev);411 int ret;412 413 mutex_lock(&data->mutex);414 ret = sx_common_update_chan_en(data, 0, data->chan_event);415 mutex_unlock(&data->mutex);416 return ret;417}418 419static const struct iio_buffer_setup_ops sx_common_buffer_setup_ops = {420 .preenable = sx_common_buffer_preenable,421 .postdisable = sx_common_buffer_postdisable,422};423 424void sx_common_get_raw_register_config(struct device *dev,425 struct sx_common_reg_default *reg_def)426{427#ifdef CONFIG_ACPI428 struct acpi_device *adev = ACPI_COMPANION(dev);429 u32 raw = 0, ret;430 char prop[80];431 432 if (!reg_def->property || !adev)433 return;434 435 snprintf(prop, ARRAY_SIZE(prop), "%s,reg_%s", acpi_device_hid(adev), reg_def->property);436 ret = device_property_read_u32(dev, prop, &raw);437 if (ret)438 return;439 440 reg_def->def = raw;441#endif442}443EXPORT_SYMBOL_NS_GPL(sx_common_get_raw_register_config, SEMTECH_PROX);444 445#define SX_COMMON_SOFT_RESET 0xde446 447static int sx_common_init_device(struct device *dev, struct iio_dev *indio_dev)448{449 struct sx_common_data *data = iio_priv(indio_dev);450 struct sx_common_reg_default tmp;451 const struct sx_common_reg_default *initval;452 int ret;453 unsigned int i, val;454 455 ret = regmap_write(data->regmap, data->chip_info->reg_reset,456 SX_COMMON_SOFT_RESET);457 if (ret)458 return ret;459 460 usleep_range(1000, 2000); /* power-up time is ~1ms. */461 462 /* Clear reset interrupt state by reading SX_COMMON_REG_IRQ_SRC. */463 ret = regmap_read(data->regmap, SX_COMMON_REG_IRQ_SRC, &val);464 if (ret)465 return ret;466 467 /* Program defaults from constant or BIOS. */468 for (i = 0; i < data->chip_info->num_default_regs; i++) {469 initval = data->chip_info->ops.get_default_reg(dev, i, &tmp);470 ret = regmap_write(data->regmap, initval->reg, initval->def);471 if (ret)472 return ret;473 }474 475 return data->chip_info->ops.init_compensation(indio_dev);476}477 478/**479 * sx_common_probe() - Common setup for Semtech SAR sensor480 * @client: I2C client object481 * @chip_info: Semtech sensor chip information.482 * @regmap_config: Sensor registers map configuration.483 */484int sx_common_probe(struct i2c_client *client,485 const struct sx_common_chip_info *chip_info,486 const struct regmap_config *regmap_config)487{488 static const char * const regulator_names[] = { "vdd", "svdd" };489 struct device *dev = &client->dev;490 struct iio_dev *indio_dev;491 struct sx_common_data *data;492 int ret;493 494 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));495 if (!indio_dev)496 return -ENOMEM;497 498 data = iio_priv(indio_dev);499 500 data->chip_info = chip_info;501 data->client = client;502 mutex_init(&data->mutex);503 init_completion(&data->completion);504 505 data->regmap = devm_regmap_init_i2c(client, regmap_config);506 if (IS_ERR(data->regmap))507 return dev_err_probe(dev, PTR_ERR(data->regmap),508 "Could init register map\n");509 510 ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(regulator_names),511 regulator_names);512 if (ret)513 return dev_err_probe(dev, ret, "Unable to get regulators\n");514 515 /* Must wait for Tpor time after initial power up */516 usleep_range(1000, 1100);517 518 ret = data->chip_info->ops.check_whoami(dev, indio_dev);519 if (ret)520 return dev_err_probe(dev, ret, "error reading WHOAMI\n");521 522 indio_dev->modes = INDIO_DIRECT_MODE;523 524 indio_dev->channels = data->chip_info->iio_channels;525 indio_dev->num_channels = data->chip_info->num_iio_channels;526 indio_dev->info = &data->chip_info->iio_info;527 528 i2c_set_clientdata(client, indio_dev);529 530 ret = sx_common_init_device(dev, indio_dev);531 if (ret)532 return dev_err_probe(dev, ret, "Unable to initialize sensor\n");533 534 if (client->irq) {535 ret = devm_request_threaded_irq(dev, client->irq,536 sx_common_irq_handler,537 sx_common_irq_thread_handler,538 IRQF_ONESHOT,539 "sx_event", indio_dev);540 if (ret)541 return dev_err_probe(dev, ret, "No IRQ\n");542 543 data->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",544 indio_dev->name,545 iio_device_id(indio_dev));546 if (!data->trig)547 return -ENOMEM;548 549 data->trig->ops = &sx_common_trigger_ops;550 iio_trigger_set_drvdata(data->trig, indio_dev);551 552 ret = devm_iio_trigger_register(dev, data->trig);553 if (ret)554 return ret;555 }556 557 ret = devm_iio_triggered_buffer_setup(dev, indio_dev,558 iio_pollfunc_store_time,559 sx_common_trigger_handler,560 &sx_common_buffer_setup_ops);561 if (ret)562 return ret;563 564 return devm_iio_device_register(dev, indio_dev);565}566EXPORT_SYMBOL_NS_GPL(sx_common_probe, SEMTECH_PROX);567 568MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");569MODULE_DESCRIPTION("Common functions and structures for Semtech sensor");570MODULE_LICENSE("GPL v2");571