| /* |
| * STMicroelectronics st_asm330lhh FIFO buffer library driver |
| * |
| * Copyright 2020 STMicroelectronics Inc. |
| * |
| * Lorenzo Bianconi <lorenzo.bianconi@st.com> |
| * |
| * Licensed under the GPL-2. |
| */ |
| #include <linux/module.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/iio/iio.h> |
| #include <linux/iio/kfifo_buf.h> |
| #include <linux/iio/events.h> |
| #include <asm/unaligned.h> |
| #include <linux/iio/buffer.h> |
| #include <linux/of.h> |
| |
| #include "st_asm330lhh.h" |
| |
| #define ST_ASM330LHH_REG_FIFO_THL_ADDR 0x07 |
| #define ST_ASM330LHH_REG_FIFO_LEN_MASK GENMASK(8, 0) |
| #define ST_ASM330LHH_REG_FIFO_STATUS_DIFF GENMASK(9, 0) |
| #define ST_ASM330LHH_REG_FIFO_MODE_MASK GENMASK(2, 0) |
| #define ST_ASM330LHH_REG_DEC_TS_MASK GENMASK(7, 6) |
| #define ST_ASM330LHH_REG_HLACTIVE_ADDR 0x12 |
| #define ST_ASM330LHH_REG_HLACTIVE_MASK BIT(5) |
| #define ST_ASM330LHH_REG_PP_OD_ADDR 0x12 |
| #define ST_ASM330LHH_REG_PP_OD_MASK BIT(4) |
| #define ST_ASM330LHH_REG_FIFO_STATUS1_ADDR 0x3a |
| #define ST_ASM330LHH_REG_TS0_ADDR 0x40 |
| #define ST_ASM330LHH_REG_TS2_ADDR 0x42 |
| #define ST_ASM330LHH_REG_FIFO_OUT_TAG_ADDR 0x78 |
| |
| #define ST_ASM330LHH_SAMPLE_DISCHARD 0x7ffd |
| |
| /* Timestamp convergence filter parameter */ |
| #define ST_ASM330LHH_EWMA_LEVEL 120 |
| #define ST_ASM330LHH_EWMA_DIV 128 |
| |
| enum { |
| ST_ASM330LHH_GYRO_TAG = 0x01, |
| ST_ASM330LHH_ACC_TAG = 0x02, |
| ST_ASM330LHH_TS_TAG = 0x04, |
| }; |
| |
| static inline s64 st_asm330lhh_ewma(s64 old, s64 new, int weight) |
| { |
| s64 diff, incr; |
| |
| diff = new - old; |
| incr = div_s64((ST_ASM330LHH_EWMA_DIV - weight) * diff, |
| ST_ASM330LHH_EWMA_DIV); |
| |
| return old + incr; |
| } |
| |
| static inline int st_asm330lhh_reset_hwts(struct st_asm330lhh_hw *hw) |
| { |
| u8 data = 0xaa; |
| |
| hw->ts = st_asm330lhh_get_time_ns(); |
| hw->ts_offset = hw->ts; |
| hw->val_ts_old = 0; |
| hw->hw_ts_high = 0; |
| hw->tsample = 0ull; |
| |
| if (hw->asm330_hrtimer) |
| st_asm330lhh_set_cpu_idle_state(true); |
| |
| return hw->tf->write(hw->dev, ST_ASM330LHH_REG_TS2_ADDR, sizeof(data), |
| &data); |
| } |
| |
| int st_asm330lhh_set_fifo_mode(struct st_asm330lhh_hw *hw, |
| enum st_asm330lhh_fifo_mode fifo_mode) |
| { |
| int err; |
| |
| err = st_asm330lhh_write_with_mask(hw, ST_ASM330LHH_REG_FIFO_CTRL4_ADDR, |
| ST_ASM330LHH_REG_FIFO_MODE_MASK, |
| fifo_mode); |
| if (err < 0) |
| return err; |
| |
| hw->fifo_mode = fifo_mode; |
| |
| if (fifo_mode == ST_ASM330LHH_FIFO_BYPASS) |
| clear_bit(ST_ASM330LHH_HW_OPERATIONAL, &hw->state); |
| else |
| set_bit(ST_ASM330LHH_HW_OPERATIONAL, &hw->state); |
| |
| return 0; |
| } |
| |
| static int st_asm330lhh_set_sensor_batching_odr(struct st_asm330lhh_sensor *sensor, |
| bool enable) |
| { |
| struct st_asm330lhh_hw *hw = sensor->hw; |
| u8 data = 0; |
| int err; |
| |
| if (enable) { |
| err = st_asm330lhh_get_odr_val(sensor->id, sensor->odr, &data); |
| if (err < 0) |
| return err; |
| } |
| |
| return st_asm330lhh_write_with_mask(hw, |
| sensor->batch_addr, |
| sensor->batch_mask, data); |
| } |
| |
| int st_asm330lhh_update_watermark(struct st_asm330lhh_sensor *sensor, |
| u16 watermark) |
| { |
| u16 fifo_watermark = ST_ASM330LHH_MAX_FIFO_DEPTH, cur_watermark = 0; |
| struct st_asm330lhh_hw *hw = sensor->hw; |
| struct st_asm330lhh_sensor *cur_sensor; |
| __le16 wdata; |
| int i, err; |
| u8 data; |
| |
| for (i = 0; i < ST_ASM330LHH_ID_MAX; i++) { |
| if (!hw->iio_devs[i]) |
| continue; |
| |
| cur_sensor = iio_priv(hw->iio_devs[i]); |
| |
| if (!(hw->enable_mask & BIT(cur_sensor->id))) |
| continue; |
| |
| cur_watermark = (cur_sensor == sensor) ? watermark |
| : cur_sensor->watermark; |
| |
| fifo_watermark = min_t(u16, fifo_watermark, cur_watermark); |
| } |
| |
| fifo_watermark = max_t(u16, fifo_watermark, 2); |
| |
| mutex_lock(&hw->lock); |
| |
| err = hw->tf->read(hw->dev, ST_ASM330LHH_REG_FIFO_THL_ADDR + 1, |
| sizeof(data), &data); |
| if (err < 0) |
| goto out; |
| |
| fifo_watermark = ((data << 8) & ~ST_ASM330LHH_REG_FIFO_LEN_MASK) | |
| (fifo_watermark & ST_ASM330LHH_REG_FIFO_LEN_MASK); |
| wdata = cpu_to_le16(fifo_watermark); |
| err = hw->tf->write(hw->dev, ST_ASM330LHH_REG_FIFO_THL_ADDR, |
| sizeof(wdata), (u8 *)&wdata); |
| |
| out: |
| mutex_unlock(&hw->lock); |
| |
| return err < 0 ? err : 0; |
| } |
| |
| static struct iio_dev *st_asm330lhh_get_iiodev_from_tag(struct st_asm330lhh_hw *hw, |
| u8 tag) |
| { |
| struct iio_dev *iio_dev; |
| |
| switch (tag) { |
| case ST_ASM330LHH_GYRO_TAG: |
| iio_dev = hw->iio_devs[ST_ASM330LHH_ID_GYRO]; |
| break; |
| case ST_ASM330LHH_ACC_TAG: |
| iio_dev = hw->iio_devs[ST_ASM330LHH_ID_ACC]; |
| break; |
| default: |
| iio_dev = NULL; |
| break; |
| } |
| |
| return iio_dev; |
| } |
| #ifdef CONFIG_ENABLE_ASM_ACC_GYRO_BUFFERING |
| int asm330_check_acc_gyro_early_buff_enable_flag( |
| struct st_asm330lhh_sensor *sensor) |
| { |
| if (sensor->buffer_asm_samples == true) |
| return 1; |
| else |
| return 0; |
| } |
| #else |
| int asm330_check_acc_gyro_early_buff_enable_flag( |
| struct st_asm330lhh_sensor *sensor) |
| { |
| return 0; |
| } |
| #endif |
| |
| #ifdef CONFIG_ENABLE_ASM_ACC_GYRO_BUFFERING |
| static void store_acc_gyro_boot_sample(struct st_asm330lhh_sensor *sensor, |
| u8 *iio_buf, s64 tsample) |
| { |
| int x, y, z; |
| |
| if (false == sensor->buffer_asm_samples) |
| return; |
| |
| mutex_lock(&sensor->sensor_buff); |
| sensor->timestamp = (ktime_t)tsample; |
| x = iio_buf[1]<<8|iio_buf[0]; |
| y = iio_buf[3]<<8|iio_buf[2]; |
| z = iio_buf[5]<<8|iio_buf[4]; |
| |
| if (ktime_to_timespec(sensor->timestamp).tv_sec |
| < sensor->max_buffer_time) { |
| if (sensor->bufsample_cnt < ASM_MAXSAMPLE) { |
| sensor->asm_samplist[sensor->bufsample_cnt]->xyz[0] = x; |
| sensor->asm_samplist[sensor->bufsample_cnt]->xyz[1] = y; |
| sensor->asm_samplist[sensor->bufsample_cnt]->xyz[2] = z; |
| sensor->asm_samplist[sensor->bufsample_cnt]->tsec = |
| ktime_to_timespec(sensor->timestamp).tv_sec; |
| sensor->asm_samplist[sensor->bufsample_cnt]->tnsec = |
| ktime_to_timespec(sensor->timestamp).tv_nsec; |
| sensor->bufsample_cnt++; |
| } |
| } else { |
| dev_info(sensor->hw->dev, "End of sensor %d buffering %d\n", |
| sensor->id, sensor->bufsample_cnt); |
| sensor->buffer_asm_samples = false; |
| } |
| mutex_unlock(&sensor->sensor_buff); |
| } |
| #else |
| static void store_acc_gyro_boot_sample(struct st_asm330lhh_sensor *sensor, |
| u8 *iio_buf, s64 tsample) |
| { |
| } |
| #endif |
| |
| static inline void st_asm330lhh_sync_hw_ts(struct st_asm330lhh_hw *hw, s64 ts) |
| { |
| s64 delta = ts - hw->hw_ts; |
| |
| hw->ts_offset = st_asm330lhh_ewma(hw->ts_offset, delta, |
| ST_ASM330LHH_EWMA_LEVEL); |
| } |
| |
| static int st_asm330lhh_read_fifo(struct st_asm330lhh_hw *hw) |
| { |
| u8 iio_buf[ALIGN(ST_ASM330LHH_SAMPLE_SIZE, sizeof(s64)) + sizeof(s64)]; |
| u8 buf[30 * ST_ASM330LHH_FIFO_SAMPLE_SIZE], tag, *ptr; |
| int i, err, word_len, fifo_len, read_len; |
| struct iio_dev *iio_dev; |
| struct st_asm330lhh_sensor *sensor; |
| s64 ts_irq, hw_ts_old; |
| __le16 fifo_status; |
| u16 fifo_depth; |
| s16 drdymask; |
| u32 val; |
| |
| /* return if FIFO is already disabled */ |
| if (!test_bit(ST_ASM330LHH_HW_OPERATIONAL, &hw->state)) { |
| dev_warn(hw->dev, "%s: FIFO in bypass mode\n", __func__); |
| |
| return 0; |
| } |
| |
| ts_irq = hw->ts - hw->delta_ts; |
| |
| err = st_asm330lhh_read_atomic(hw, ST_ASM330LHH_REG_FIFO_STATUS1_ADDR, |
| sizeof(fifo_status), (u8 *)&fifo_status); |
| if (err < 0) |
| return err; |
| |
| fifo_depth = le16_to_cpu(fifo_status) & |
| ST_ASM330LHH_REG_FIFO_STATUS_DIFF; |
| if (!fifo_depth) |
| return 0; |
| |
| fifo_len = fifo_depth * ST_ASM330LHH_FIFO_SAMPLE_SIZE; |
| read_len = 0; |
| while (read_len < fifo_len) { |
| word_len = min_t(int, fifo_len - read_len, sizeof(buf)); |
| err = st_asm330lhh_read_atomic(hw, |
| ST_ASM330LHH_REG_FIFO_OUT_TAG_ADDR, |
| word_len, buf); |
| if (err < 0) |
| return err; |
| for (i = 0; i < word_len; i += ST_ASM330LHH_FIFO_SAMPLE_SIZE) { |
| ptr = &buf[i + ST_ASM330LHH_TAG_SIZE]; |
| tag = buf[i] >> 3; |
| |
| if (tag == ST_ASM330LHH_TS_TAG) { |
| val = get_unaligned_le32(ptr); |
| |
| if (hw->val_ts_old > val) |
| hw->hw_ts_high++; |
| |
| hw_ts_old = hw->hw_ts; |
| |
| /* check hw rollover */ |
| hw->val_ts_old = val; |
| hw->hw_ts = (val + ((s64)hw->hw_ts_high << |
| 32)) * hw->ts_delta_ns; |
| hw->ts_offset = st_asm330lhh_ewma(hw->ts_offset, |
| ts_irq - hw->hw_ts, |
| ST_ASM330LHH_EWMA_LEVEL); |
| |
| if (!test_bit(ST_ASM330LHH_HW_FLUSH, |
| &hw->state)) |
| /* sync ap timestamp and sensor one */ |
| st_asm330lhh_sync_hw_ts(hw, ts_irq); |
| |
| ts_irq += hw->hw_ts; |
| |
| if (!hw->tsample) |
| hw->tsample = hw->ts_offset + hw->hw_ts; |
| else |
| hw->tsample = hw->tsample + |
| hw->hw_ts - hw_ts_old; |
| } else { |
| iio_dev = st_asm330lhh_get_iiodev_from_tag(hw, |
| tag); |
| if (!iio_dev) |
| continue; |
| sensor = iio_priv(iio_dev); |
| |
| /* skip samples if not ready */ |
| drdymask = (s16)le16_to_cpu( |
| get_unaligned_le16(ptr)); |
| if (unlikely(drdymask |
| >= ST_ASM330LHH_SAMPLE_DISCHARD)) { |
| continue; |
| } |
| memcpy(iio_buf, ptr, ST_ASM330LHH_SAMPLE_SIZE); |
| |
| hw->tsample = min_t(s64, |
| hw->ts, |
| hw->tsample); |
| |
| iio_push_to_buffers_with_timestamp(iio_dev, |
| iio_buf, |
| hw->tsample); |
| store_acc_gyro_boot_sample(sensor, |
| iio_buf, hw->tsample); |
| } |
| } |
| read_len += word_len; |
| } |
| |
| return read_len; |
| } |
| |
| ssize_t st_asm330lhh_get_max_watermark(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| return sprintf(buf, "%d\n", ST_ASM330LHH_MAX_FIFO_DEPTH); |
| } |
| |
| ssize_t st_asm330lhh_get_watermark(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct iio_dev *iio_dev = dev_get_drvdata(dev); |
| struct st_asm330lhh_sensor *sensor = iio_priv(iio_dev); |
| |
| return sprintf(buf, "%d\n", sensor->watermark); |
| } |
| |
| ssize_t st_asm330lhh_set_watermark(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t size) |
| { |
| struct iio_dev *iio_dev = dev_get_drvdata(dev); |
| struct st_asm330lhh_sensor *sensor = iio_priv(iio_dev); |
| int err, val; |
| |
| if (asm330_check_acc_gyro_early_buff_enable_flag(sensor)) |
| return -EBUSY; |
| |
| mutex_lock(&iio_dev->mlock); |
| if (iio_buffer_enabled(iio_dev)) { |
| err = -EBUSY; |
| goto out; |
| } |
| |
| err = kstrtoint(buf, 10, &val); |
| if (err < 0) |
| goto out; |
| |
| err = st_asm330lhh_update_watermark(sensor, val); |
| if (err < 0) |
| goto out; |
| |
| sensor->watermark = val; |
| |
| out: |
| mutex_unlock(&iio_dev->mlock); |
| |
| return err < 0 ? err : size; |
| } |
| |
| ssize_t st_asm330lhh_flush_fifo(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t size) |
| { |
| struct iio_dev *iio_dev = dev_get_drvdata(dev); |
| struct st_asm330lhh_sensor *sensor = iio_priv(iio_dev); |
| struct st_asm330lhh_hw *hw = sensor->hw; |
| s64 event; |
| int count; |
| s64 type; |
| s64 ts; |
| |
| mutex_lock(&hw->fifo_lock); |
| ts = st_asm330lhh_get_time_ns(); |
| hw->delta_ts = ts - hw->ts; |
| hw->ts = ts; |
| set_bit(ST_ASM330LHH_HW_FLUSH, &hw->state); |
| count = st_asm330lhh_read_fifo(hw); |
| mutex_unlock(&hw->fifo_lock); |
| |
| type = count > 0 ? CUSTOM_IIO_EV_DIR_FIFO_DATA : CUSTOM_IIO_EV_DIR_FIFO_EMPTY; |
| event = IIO_UNMOD_EVENT_CODE(iio_dev->channels[0].type, -1, |
| CUSTOM_IIO_EV_TYPE_FIFO_FLUSH, type); |
| iio_push_event(iio_dev, event, st_asm330lhh_get_time_ns()); |
| |
| return size; |
| } |
| |
| int st_asm330lhh_suspend_fifo(struct st_asm330lhh_hw *hw) |
| { |
| int err; |
| |
| mutex_lock(&hw->fifo_lock); |
| st_asm330lhh_read_fifo(hw); |
| err = st_asm330lhh_set_fifo_mode(hw, ST_ASM330LHH_FIFO_BYPASS); |
| mutex_unlock(&hw->fifo_lock); |
| |
| return err; |
| } |
| |
| int st_asm330lhh_update_fifo(struct iio_dev *iio_dev, bool enable) |
| { |
| struct st_asm330lhh_sensor *sensor = iio_priv(iio_dev); |
| struct st_asm330lhh_hw *hw = sensor->hw; |
| int err; |
| |
| mutex_lock(&hw->fifo_lock); |
| |
| err = st_asm330lhh_sensor_set_enable(sensor, enable); |
| if (err < 0) |
| goto out; |
| |
| err = st_asm330lhh_set_sensor_batching_odr(sensor, enable); |
| if (err < 0) |
| goto out; |
| |
| err = st_asm330lhh_update_watermark(sensor, sensor->watermark); |
| if (err < 0) |
| goto out; |
| |
| if (enable && hw->fifo_mode == ST_ASM330LHH_FIFO_BYPASS) { |
| st_asm330lhh_reset_hwts(hw); |
| err = st_asm330lhh_set_fifo_mode(hw, ST_ASM330LHH_FIFO_CONT); |
| } else if (!hw->enable_mask) { |
| err = st_asm330lhh_set_fifo_mode(hw, ST_ASM330LHH_FIFO_BYPASS); |
| } |
| |
| out: |
| mutex_unlock(&hw->fifo_lock); |
| |
| return err; |
| } |
| |
| static irqreturn_t st_asm330lhh_handler_irq(int irq, void *private) |
| { |
| struct st_asm330lhh_hw *hw = (struct st_asm330lhh_hw *)private; |
| s64 ts = st_asm330lhh_get_time_ns(); |
| |
| hw->delta_ts = ts - hw->ts; |
| hw->ts = ts; |
| |
| if (hw->asm330_hrtimer) |
| st_asm330lhh_hrtimer_reset(hw, hw->delta_ts); |
| |
| return IRQ_WAKE_THREAD; |
| } |
| |
| static irqreturn_t st_asm330lhh_handler_thread(int irq, void *private) |
| { |
| struct st_asm330lhh_hw *hw = (struct st_asm330lhh_hw *)private; |
| |
| mutex_lock(&hw->fifo_lock); |
| st_asm330lhh_read_fifo(hw); |
| clear_bit(ST_ASM330LHH_HW_FLUSH, &hw->state); |
| mutex_unlock(&hw->fifo_lock); |
| |
| if (hw->asm330_hrtimer) |
| st_asm330lhh_set_cpu_idle_state(false); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int st_asm330lhh_buffer_preenable(struct iio_dev *iio_dev) |
| { |
| struct st_asm330lhh_sensor *sensor = iio_priv(iio_dev); |
| |
| if (asm330_check_acc_gyro_early_buff_enable_flag(sensor)) |
| return 0; |
| else |
| return st_asm330lhh_update_fifo(iio_dev, true); |
| } |
| |
| static int st_asm330lhh_buffer_postdisable(struct iio_dev *iio_dev) |
| { |
| struct st_asm330lhh_sensor *sensor = iio_priv(iio_dev); |
| |
| if (asm330_check_acc_gyro_early_buff_enable_flag(sensor)) |
| return 0; |
| else |
| return st_asm330lhh_update_fifo(iio_dev, false); |
| } |
| |
| static const struct iio_buffer_setup_ops st_asm330lhh_buffer_ops = { |
| .preenable = st_asm330lhh_buffer_preenable, |
| .postdisable = st_asm330lhh_buffer_postdisable, |
| }; |
| |
| static int st_asm330lhh_fifo_init(struct st_asm330lhh_hw *hw) |
| { |
| return st_asm330lhh_write_with_mask(hw, ST_ASM330LHH_REG_FIFO_CTRL4_ADDR, |
| ST_ASM330LHH_REG_DEC_TS_MASK, 1); |
| } |
| |
| int st_asm330lhh_fifo_setup(struct st_asm330lhh_hw *hw) |
| { |
| struct device_node *np = hw->dev->of_node; |
| struct iio_buffer *buffer; |
| unsigned long irq_type; |
| bool irq_active_low; |
| int i, err; |
| |
| irq_type = irqd_get_trigger_type(irq_get_irq_data(hw->irq)); |
| if (irq_type == IRQF_TRIGGER_NONE) |
| irq_type = IRQF_TRIGGER_HIGH; |
| |
| switch (irq_type) { |
| case IRQF_TRIGGER_HIGH: |
| case IRQF_TRIGGER_RISING: |
| irq_active_low = false; |
| break; |
| case IRQF_TRIGGER_LOW: |
| case IRQF_TRIGGER_FALLING: |
| irq_active_low = true; |
| break; |
| default: |
| dev_info(hw->dev, "mode %lx unsupported\n", irq_type); |
| return -EINVAL; |
| } |
| |
| err = st_asm330lhh_write_with_mask(hw, ST_ASM330LHH_REG_HLACTIVE_ADDR, |
| ST_ASM330LHH_REG_HLACTIVE_MASK, |
| irq_active_low); |
| if (err < 0) |
| return err; |
| |
| if (np && of_property_read_bool(np, "drive-open-drain")) { |
| err = st_asm330lhh_write_with_mask(hw, |
| ST_ASM330LHH_REG_PP_OD_ADDR, |
| ST_ASM330LHH_REG_PP_OD_MASK, 1); |
| if (err < 0) |
| return err; |
| |
| irq_type |= IRQF_SHARED; |
| } |
| |
| err = devm_request_threaded_irq(hw->dev, hw->irq, |
| st_asm330lhh_handler_irq, |
| st_asm330lhh_handler_thread, |
| irq_type | IRQF_ONESHOT, |
| "asm330lhh", hw); |
| if (err) { |
| dev_err(hw->dev, "failed to request trigger irq %d\n", |
| hw->irq); |
| return err; |
| } |
| |
| for (i = ST_ASM330LHH_ID_ACC; i < ST_ASM330LHH_ID_MAX; i++) { |
| if (!hw->iio_devs[i]) |
| continue; |
| |
| buffer = devm_iio_kfifo_allocate(hw->dev); |
| if (!buffer) |
| return -ENOMEM; |
| |
| iio_device_attach_buffer(hw->iio_devs[i], buffer); |
| hw->iio_devs[i]->modes |= INDIO_BUFFER_SOFTWARE; |
| hw->iio_devs[i]->setup_ops = &st_asm330lhh_buffer_ops; |
| } |
| |
| return st_asm330lhh_fifo_init(hw); |
| } |