// SPDX-License-Identifier: GPL-2.0 /* * cros_ec_sensors_core - Common function for Chrome OS EC sensor driver. * * Copyright (C) 2016 Google, Inc */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Hard coded to the first device to support sensor fifo. The EC has a 2048 * byte fifo and will trigger an interrupt when fifo is 2/3 full. */ #define CROS_EC_FIFO_SIZE (2048 * 2 / 3) static char *cros_ec_loc[] = { [MOTIONSENSE_LOC_BASE] = "base", [MOTIONSENSE_LOC_LID] = "lid", [MOTIONSENSE_LOC_MAX] = "unknown", }; static int cros_ec_get_host_cmd_version_mask(struct cros_ec_device *ec_dev, u16 cmd_offset, u16 cmd, u32 *mask) { int ret; struct { struct cros_ec_command msg; union { struct ec_params_get_cmd_versions params; struct ec_response_get_cmd_versions resp; }; } __packed buf = { .msg = { .command = EC_CMD_GET_CMD_VERSIONS + cmd_offset, .insize = sizeof(struct ec_response_get_cmd_versions), .outsize = sizeof(struct ec_params_get_cmd_versions) }, .params = {.cmd = cmd} }; ret = cros_ec_cmd_xfer_status(ec_dev, &buf.msg); if (ret >= 0) *mask = buf.resp.version_mask; return ret; } static void get_default_min_max_freq(enum motionsensor_type type, u32 *min_freq, u32 *max_freq, u32 *max_fifo_events) { /* * We don't know fifo size, set to size previously used by older * hardware. */ *max_fifo_events = CROS_EC_FIFO_SIZE; switch (type) { case MOTIONSENSE_TYPE_ACCEL: case MOTIONSENSE_TYPE_GYRO: *min_freq = 12500; *max_freq = 100000; break; case MOTIONSENSE_TYPE_MAG: *min_freq = 5000; *max_freq = 25000; break; case MOTIONSENSE_TYPE_PROX: case MOTIONSENSE_TYPE_LIGHT: *min_freq = 100; *max_freq = 50000; break; case MOTIONSENSE_TYPE_BARO: *min_freq = 250; *max_freq = 20000; break; case MOTIONSENSE_TYPE_ACTIVITY: default: *min_freq = 0; *max_freq = 0; break; } } static int cros_ec_sensor_set_ec_rate(struct cros_ec_sensors_core_state *st, int rate) { int ret; if (rate > U16_MAX) rate = U16_MAX; mutex_lock(&st->cmd_lock); st->param.cmd = MOTIONSENSE_CMD_EC_RATE; st->param.ec_rate.data = rate; ret = cros_ec_motion_send_host_cmd(st, 0); mutex_unlock(&st->cmd_lock); return ret; } static ssize_t cros_ec_sensor_set_report_latency(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); int integer, fract, ret; int latency; ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract); if (ret) return ret; /* EC rate is in ms. */ latency = integer * 1000 + fract / 1000; ret = cros_ec_sensor_set_ec_rate(st, latency); if (ret < 0) return ret; return len; } static ssize_t cros_ec_sensor_get_report_latency(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); int latency, ret; mutex_lock(&st->cmd_lock); st->param.cmd = MOTIONSENSE_CMD_EC_RATE; st->param.ec_rate.data = EC_MOTION_SENSE_NO_VALUE; ret = cros_ec_motion_send_host_cmd(st, 0); latency = st->resp->ec_rate.ret; mutex_unlock(&st->cmd_lock); if (ret < 0) return ret; return sprintf(buf, "%d.%06u\n", latency / 1000, (latency % 1000) * 1000); } static IIO_DEVICE_ATTR(hwfifo_timeout, 0644, cros_ec_sensor_get_report_latency, cros_ec_sensor_set_report_latency, 0); static ssize_t hwfifo_watermark_max_show(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); return sprintf(buf, "%d\n", st->fifo_max_event_count); } static IIO_DEVICE_ATTR_RO(hwfifo_watermark_max, 0); const struct attribute *cros_ec_sensor_fifo_attributes[] = { &iio_dev_attr_hwfifo_timeout.dev_attr.attr, &iio_dev_attr_hwfifo_watermark_max.dev_attr.attr, NULL, }; EXPORT_SYMBOL_GPL(cros_ec_sensor_fifo_attributes); int cros_ec_sensors_push_data(struct iio_dev *indio_dev, s16 *data, s64 timestamp) { struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); s16 *out; s64 delta; unsigned int i; /* * Ignore samples if the buffer is not set: it is needed if the ODR is * set but the buffer is not enabled yet. */ if (!iio_buffer_enabled(indio_dev)) return 0; out = (s16 *)st->samples; for_each_set_bit(i, indio_dev->active_scan_mask, indio_dev->masklength) { *out = data[i]; out++; } if (iio_device_get_clock(indio_dev) != CLOCK_BOOTTIME) delta = iio_get_time_ns(indio_dev) - cros_ec_get_time_ns(); else delta = 0; iio_push_to_buffers_with_timestamp(indio_dev, st->samples, timestamp + delta); return 0; } EXPORT_SYMBOL_GPL(cros_ec_sensors_push_data); static void cros_ec_sensors_core_clean(void *arg) { struct platform_device *pdev = (struct platform_device *)arg; struct cros_ec_sensorhub *sensor_hub = dev_get_drvdata(pdev->dev.parent); struct iio_dev *indio_dev = platform_get_drvdata(pdev); struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); u8 sensor_num = st->param.info.sensor_num; cros_ec_sensorhub_unregister_push_data(sensor_hub, sensor_num); } /** * cros_ec_sensors_core_init() - basic initialization of the core structure * @pdev: platform device created for the sensors * @indio_dev: iio device structure of the device * @physical_device: true if the device refers to a physical device * @trigger_capture: function pointer to call buffer is triggered, * for backward compatibility. * @push_data: function to call when cros_ec_sensorhub receives * a sample for that sensor. * * Return: 0 on success, -errno on failure. */ int cros_ec_sensors_core_init(struct platform_device *pdev, struct iio_dev *indio_dev, bool physical_device, cros_ec_sensors_capture_t trigger_capture, cros_ec_sensorhub_push_data_cb_t push_data) { struct device *dev = &pdev->dev; struct cros_ec_sensors_core_state *state = iio_priv(indio_dev); struct cros_ec_sensorhub *sensor_hub = dev_get_drvdata(dev->parent); struct cros_ec_dev *ec = sensor_hub->ec; struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev); u32 ver_mask; int frequencies[ARRAY_SIZE(state->frequencies) / 2] = { 0 }; int ret, i; platform_set_drvdata(pdev, indio_dev); state->ec = ec->ec_dev; state->msg = devm_kzalloc(&pdev->dev, max((u16)sizeof(struct ec_params_motion_sense), state->ec->max_response), GFP_KERNEL); if (!state->msg) return -ENOMEM; state->resp = (struct ec_response_motion_sense *)state->msg->data; mutex_init(&state->cmd_lock); ret = cros_ec_get_host_cmd_version_mask(state->ec, ec->cmd_offset, EC_CMD_MOTION_SENSE_CMD, &ver_mask); if (ret < 0) return ret; /* Set up the host command structure. */ state->msg->version = fls(ver_mask) - 1; state->msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset; state->msg->outsize = sizeof(struct ec_params_motion_sense); indio_dev->dev.parent = &pdev->dev; indio_dev->name = pdev->name; if (physical_device) { state->param.cmd = MOTIONSENSE_CMD_INFO; state->param.info.sensor_num = sensor_platform->sensor_num; ret = cros_ec_motion_send_host_cmd(state, 0); if (ret) { dev_warn(dev, "Can not access sensor info\n"); return ret; } state->type = state->resp->info.type; state->loc = state->resp->info.location; /* Set sign vector, only used for backward compatibility. */ memset(state->sign, 1, CROS_EC_SENSOR_MAX_AXIS); for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++) state->calib[i].scale = MOTION_SENSE_DEFAULT_SCALE; /* 0 is a correct value used to stop the device */ if (state->msg->version < 3) { get_default_min_max_freq(state->resp->info.type, &frequencies[1], &frequencies[2], &state->fifo_max_event_count); } else { frequencies[1] = state->resp->info_3.min_frequency; frequencies[2] = state->resp->info_3.max_frequency; state->fifo_max_event_count = state->resp->info_3.fifo_max_event_count; } for (i = 0; i < ARRAY_SIZE(frequencies); i++) { state->frequencies[2 * i] = frequencies[i] / 1000; state->frequencies[2 * i + 1] = (frequencies[i] % 1000) * 1000; } if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) { /* * Create a software buffer, feed by the EC FIFO. * We can not use trigger here, as events are generated * as soon as sample_frequency is set. */ struct iio_buffer *buffer; buffer = devm_iio_kfifo_allocate(dev); if (!buffer) return -ENOMEM; iio_device_attach_buffer(indio_dev, buffer); indio_dev->modes = INDIO_BUFFER_SOFTWARE; ret = cros_ec_sensorhub_register_push_data( sensor_hub, sensor_platform->sensor_num, indio_dev, push_data); if (ret) return ret; ret = devm_add_action_or_reset( dev, cros_ec_sensors_core_clean, pdev); if (ret) return ret; /* Timestamp coming from FIFO are in ns since boot. */ ret = iio_device_set_clock(indio_dev, CLOCK_BOOTTIME); if (ret) return ret; } else { /* * The only way to get samples in buffer is to set a * software tigger (systrig, hrtimer). */ ret = devm_iio_triggered_buffer_setup( dev, indio_dev, NULL, trigger_capture, NULL); if (ret) return ret; } } return 0; } EXPORT_SYMBOL_GPL(cros_ec_sensors_core_init); /** * cros_ec_motion_send_host_cmd() - send motion sense host command * @state: pointer to state information for device * @opt_length: optional length to reduce the response size, useful on the data * path. Otherwise, the maximal allowed response size is used * * When called, the sub-command is assumed to be set in param->cmd. * * Return: 0 on success, -errno on failure. */ int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *state, u16 opt_length) { int ret; if (opt_length) state->msg->insize = min(opt_length, state->ec->max_response); else state->msg->insize = state->ec->max_response; memcpy(state->msg->data, &state->param, sizeof(state->param)); ret = cros_ec_cmd_xfer_status(state->ec, state->msg); if (ret < 0) return ret; if (ret && state->resp != (struct ec_response_motion_sense *)state->msg->data) memcpy(state->resp, state->msg->data, ret); return 0; } EXPORT_SYMBOL_GPL(cros_ec_motion_send_host_cmd); static ssize_t cros_ec_sensors_calibrate(struct iio_dev *indio_dev, uintptr_t private, const struct iio_chan_spec *chan, const char *buf, size_t len) { struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); int ret, i; bool calibrate; ret = strtobool(buf, &calibrate); if (ret < 0) return ret; if (!calibrate) return -EINVAL; mutex_lock(&st->cmd_lock); st->param.cmd = MOTIONSENSE_CMD_PERFORM_CALIB; ret = cros_ec_motion_send_host_cmd(st, 0); if (ret != 0) { dev_warn(&indio_dev->dev, "Unable to calibrate sensor\n"); } else { /* Save values */ for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++) st->calib[i].offset = st->resp->perform_calib.offset[i]; } mutex_unlock(&st->cmd_lock); return ret ? ret : len; } static ssize_t cros_ec_sensors_id(struct iio_dev *indio_dev, uintptr_t private, const struct iio_chan_spec *chan, char *buf) { struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); return snprintf(buf, PAGE_SIZE, "%d\n", st->param.info.sensor_num); } static ssize_t cros_ec_sensors_loc(struct iio_dev *indio_dev, uintptr_t private, const struct iio_chan_spec *chan, char *buf) { struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); return snprintf(buf, PAGE_SIZE, "%s\n", cros_ec_loc[st->loc]); } const struct iio_chan_spec_ext_info cros_ec_sensors_ext_info[] = { { .name = "calibrate", .shared = IIO_SHARED_BY_ALL, .write = cros_ec_sensors_calibrate }, { .name = "id", .shared = IIO_SHARED_BY_ALL, .read = cros_ec_sensors_id }, { .name = "location", .shared = IIO_SHARED_BY_ALL, .read = cros_ec_sensors_loc }, { }, }; EXPORT_SYMBOL_GPL(cros_ec_sensors_ext_info); /** * cros_ec_sensors_idx_to_reg - convert index into offset in shared memory * @st: pointer to state information for device * @idx: sensor index (should be element of enum sensor_index) * * Return: address to read at */ static unsigned int cros_ec_sensors_idx_to_reg( struct cros_ec_sensors_core_state *st, unsigned int idx) { /* * When using LPC interface, only space for 2 Accel and one Gyro. * First halfword of MOTIONSENSE_TYPE_ACCEL is used by angle. */ if (st->type == MOTIONSENSE_TYPE_ACCEL) return EC_MEMMAP_ACC_DATA + sizeof(u16) * (1 + idx + st->param.info.sensor_num * CROS_EC_SENSOR_MAX_AXIS); return EC_MEMMAP_GYRO_DATA + sizeof(u16) * idx; } static int cros_ec_sensors_cmd_read_u8(struct cros_ec_device *ec, unsigned int offset, u8 *dest) { return ec->cmd_readmem(ec, offset, 1, dest); } static int cros_ec_sensors_cmd_read_u16(struct cros_ec_device *ec, unsigned int offset, u16 *dest) { __le16 tmp; int ret = ec->cmd_readmem(ec, offset, 2, &tmp); if (ret >= 0) *dest = le16_to_cpu(tmp); return ret; } /** * cros_ec_sensors_read_until_not_busy() - read until is not busy * * @st: pointer to state information for device * * Read from EC status byte until it reads not busy. * Return: 8-bit status if ok, -errno on failure. */ static int cros_ec_sensors_read_until_not_busy( struct cros_ec_sensors_core_state *st) { struct cros_ec_device *ec = st->ec; u8 status; int ret, attempts = 0; ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status); if (ret < 0) return ret; while (status & EC_MEMMAP_ACC_STATUS_BUSY_BIT) { /* Give up after enough attempts, return error. */ if (attempts++ >= 50) return -EIO; /* Small delay every so often. */ if (attempts % 5 == 0) msleep(25); ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status); if (ret < 0) return ret; } return status; } /** * read_ec_sensors_data_unsafe() - read acceleration data from EC shared memory * @indio_dev: pointer to IIO device * @scan_mask: bitmap of the sensor indices to scan * @data: location to store data * * This is the unsafe function for reading the EC data. It does not guarantee * that the EC will not modify the data as it is being read in. * * Return: 0 on success, -errno on failure. */ static int cros_ec_sensors_read_data_unsafe(struct iio_dev *indio_dev, unsigned long scan_mask, s16 *data) { struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); struct cros_ec_device *ec = st->ec; unsigned int i; int ret; /* Read all sensors enabled in scan_mask. Each value is 2 bytes. */ for_each_set_bit(i, &scan_mask, indio_dev->masklength) { ret = cros_ec_sensors_cmd_read_u16(ec, cros_ec_sensors_idx_to_reg(st, i), data); if (ret < 0) return ret; *data *= st->sign[i]; data++; } return 0; } /** * cros_ec_sensors_read_lpc() - read acceleration data from EC shared memory. * @indio_dev: pointer to IIO device. * @scan_mask: bitmap of the sensor indices to scan. * @data: location to store data. * * Note: this is the safe function for reading the EC data. It guarantees * that the data sampled was not modified by the EC while being read. * * Return: 0 on success, -errno on failure. */ int cros_ec_sensors_read_lpc(struct iio_dev *indio_dev, unsigned long scan_mask, s16 *data) { struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); struct cros_ec_device *ec = st->ec; u8 samp_id = 0xff, status = 0; int ret, attempts = 0; /* * Continually read all data from EC until the status byte after * all reads reflects that the EC is not busy and the sample id * matches the sample id from before all reads. This guarantees * that data read in was not modified by the EC while reading. */ while ((status & (EC_MEMMAP_ACC_STATUS_BUSY_BIT | EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK)) != samp_id) { /* If we have tried to read too many times, return error. */ if (attempts++ >= 5) return -EIO; /* Read status byte until EC is not busy. */ ret = cros_ec_sensors_read_until_not_busy(st); if (ret < 0) return ret; /* * Store the current sample id so that we can compare to the * sample id after reading the data. */ samp_id = ret & EC_MEMMAP_ACC_STATUS_SAMPLE_ID_MASK; /* Read all EC data, format it, and store it into data. */ ret = cros_ec_sensors_read_data_unsafe(indio_dev, scan_mask, data); if (ret < 0) return ret; /* Read status byte. */ ret = cros_ec_sensors_cmd_read_u8(ec, EC_MEMMAP_ACC_STATUS, &status); if (ret < 0) return ret; } return 0; } EXPORT_SYMBOL_GPL(cros_ec_sensors_read_lpc); /** * cros_ec_sensors_read_cmd() - retrieve data using the EC command protocol * @indio_dev: pointer to IIO device * @scan_mask: bitmap of the sensor indices to scan * @data: location to store data * * Return: 0 on success, -errno on failure. */ int cros_ec_sensors_read_cmd(struct iio_dev *indio_dev, unsigned long scan_mask, s16 *data) { struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); int ret; unsigned int i; /* Read all sensor data through a command. */ st->param.cmd = MOTIONSENSE_CMD_DATA; ret = cros_ec_motion_send_host_cmd(st, sizeof(st->resp->data)); if (ret != 0) { dev_warn(&indio_dev->dev, "Unable to read sensor data\n"); return ret; } for_each_set_bit(i, &scan_mask, indio_dev->masklength) { *data = st->resp->data.data[i]; data++; } return 0; } EXPORT_SYMBOL_GPL(cros_ec_sensors_read_cmd); /** * cros_ec_sensors_capture() - the trigger handler function * @irq: the interrupt number. * @p: a pointer to the poll function. * * On a trigger event occurring, if the pollfunc is attached then this * handler is called as a threaded interrupt (and hence may sleep). It * is responsible for grabbing data from the device and pushing it into * the associated buffer. * * Return: IRQ_HANDLED */ irqreturn_t cros_ec_sensors_capture(int irq, void *p) { struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); int ret; mutex_lock(&st->cmd_lock); /* Clear capture data. */ memset(st->samples, 0, indio_dev->scan_bytes); /* Read data based on which channels are enabled in scan mask. */ ret = st->read_ec_sensors_data(indio_dev, *(indio_dev->active_scan_mask), (s16 *)st->samples); if (ret < 0) goto done; iio_push_to_buffers_with_timestamp(indio_dev, st->samples, iio_get_time_ns(indio_dev)); done: /* * Tell the core we are done with this trigger and ready for the * next one. */ iio_trigger_notify_done(indio_dev->trig); mutex_unlock(&st->cmd_lock); return IRQ_HANDLED; } EXPORT_SYMBOL_GPL(cros_ec_sensors_capture); /** * cros_ec_sensors_core_read() - function to request a value from the sensor * @st: pointer to state information for device * @chan: channel specification structure table * @val: will contain one element making up the returned value * @val2: will contain another element making up the returned value * @mask: specifies which values to be requested * * Return: the type of value returned by the device */ int cros_ec_sensors_core_read(struct cros_ec_sensors_core_state *st, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { int ret, frequency; switch (mask) { case IIO_CHAN_INFO_SAMP_FREQ: st->param.cmd = MOTIONSENSE_CMD_SENSOR_ODR; st->param.sensor_odr.data = EC_MOTION_SENSE_NO_VALUE; ret = cros_ec_motion_send_host_cmd(st, 0); if (ret) break; frequency = st->resp->sensor_odr.ret; *val = frequency / 1000; *val2 = (frequency % 1000) * 1000; ret = IIO_VAL_INT_PLUS_MICRO; break; default: ret = -EINVAL; break; } return ret; } EXPORT_SYMBOL_GPL(cros_ec_sensors_core_read); /** * cros_ec_sensors_core_read_avail() - get available values * @indio_dev: pointer to state information for device * @chan: channel specification structure table * @vals: list of available values * @type: type of data returned * @length: number of data returned in the array * @mask: specifies which values to be requested * * Return: an error code, IIO_AVAIL_RANGE or IIO_AVAIL_LIST */ int cros_ec_sensors_core_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, const int **vals, int *type, int *length, long mask) { struct cros_ec_sensors_core_state *state = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_SAMP_FREQ: *length = ARRAY_SIZE(state->frequencies); *vals = (const int *)&state->frequencies; *type = IIO_VAL_INT_PLUS_MICRO; return IIO_AVAIL_LIST; } return -EINVAL; } EXPORT_SYMBOL_GPL(cros_ec_sensors_core_read_avail); /** * cros_ec_sensors_core_write() - function to write a value to the sensor * @st: pointer to state information for device * @chan: channel specification structure table * @val: first part of value to write * @val2: second part of value to write * @mask: specifies which values to write * * Return: the type of value returned by the device */ int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st, struct iio_chan_spec const *chan, int val, int val2, long mask) { int ret, frequency; switch (mask) { case IIO_CHAN_INFO_SAMP_FREQ: frequency = val * 1000 + val2 / 1000; st->param.cmd = MOTIONSENSE_CMD_SENSOR_ODR; st->param.sensor_odr.data = frequency; /* Always roundup, so caller gets at least what it asks for. */ st->param.sensor_odr.roundup = 1; ret = cros_ec_motion_send_host_cmd(st, 0); break; default: ret = -EINVAL; break; } return ret; } EXPORT_SYMBOL_GPL(cros_ec_sensors_core_write); MODULE_DESCRIPTION("ChromeOS EC sensor hub core functions"); MODULE_LICENSE("GPL v2");