diff options
Diffstat (limited to 'drivers/iio/imu/adis_buffer.c')
| -rw-r--r-- | drivers/iio/imu/adis_buffer.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/drivers/iio/imu/adis_buffer.c b/drivers/iio/imu/adis_buffer.c new file mode 100644 index 000000000..928933027 --- /dev/null +++ b/drivers/iio/imu/adis_buffer.c @@ -0,0 +1,216 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Common library for ADIS16XXX devices + * + * Copyright 2012 Analog Devices Inc. + * Author: Lars-Peter Clausen <lars@metafoo.de> + */ + +#include <linux/export.h> +#include <linux/interrupt.h> +#include <linux/mutex.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> +#include <linux/slab.h> + +#include <linux/iio/iio.h> +#include <linux/iio/buffer.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/iio/imu/adis.h> + +static int adis_update_scan_mode_burst(struct iio_dev *indio_dev, + const unsigned long *scan_mask) +{ + struct adis *adis = iio_device_get_drvdata(indio_dev); + unsigned int burst_length, burst_max_length; + u8 *tx; + + burst_length = adis->data->burst_len + adis->burst_extra_len; + + if (adis->data->burst_max_len) + burst_max_length = adis->data->burst_max_len; + else + burst_max_length = burst_length; + + adis->xfer = kcalloc(2, sizeof(*adis->xfer), GFP_KERNEL); + if (!adis->xfer) + return -ENOMEM; + + adis->buffer = kzalloc(burst_max_length + sizeof(u16), GFP_KERNEL); + if (!adis->buffer) { + kfree(adis->xfer); + adis->xfer = NULL; + return -ENOMEM; + } + + tx = adis->buffer + burst_max_length; + tx[0] = ADIS_READ_REG(adis->data->burst_reg_cmd); + tx[1] = 0; + + adis->xfer[0].tx_buf = tx; + adis->xfer[0].bits_per_word = 8; + adis->xfer[0].len = 2; + if (adis->data->burst_max_speed_hz) + adis->xfer[0].speed_hz = adis->data->burst_max_speed_hz; + adis->xfer[1].rx_buf = adis->buffer; + adis->xfer[1].bits_per_word = 8; + adis->xfer[1].len = burst_length; + if (adis->data->burst_max_speed_hz) + adis->xfer[1].speed_hz = adis->data->burst_max_speed_hz; + + spi_message_init(&adis->msg); + spi_message_add_tail(&adis->xfer[0], &adis->msg); + spi_message_add_tail(&adis->xfer[1], &adis->msg); + + return 0; +} + +int adis_update_scan_mode(struct iio_dev *indio_dev, + const unsigned long *scan_mask) +{ + struct adis *adis = iio_device_get_drvdata(indio_dev); + const struct iio_chan_spec *chan; + unsigned int scan_count; + unsigned int i, j; + __be16 *tx, *rx; + + kfree(adis->xfer); + kfree(adis->buffer); + + if (adis->data->burst_len) + return adis_update_scan_mode_burst(indio_dev, scan_mask); + + scan_count = indio_dev->scan_bytes / 2; + + adis->xfer = kcalloc(scan_count + 1, sizeof(*adis->xfer), GFP_KERNEL); + if (!adis->xfer) + return -ENOMEM; + + adis->buffer = kcalloc(indio_dev->scan_bytes, 2, GFP_KERNEL); + if (!adis->buffer) { + kfree(adis->xfer); + adis->xfer = NULL; + return -ENOMEM; + } + + rx = adis->buffer; + tx = rx + scan_count; + + spi_message_init(&adis->msg); + + for (j = 0; j <= scan_count; j++) { + adis->xfer[j].bits_per_word = 8; + if (j != scan_count) + adis->xfer[j].cs_change = 1; + adis->xfer[j].len = 2; + adis->xfer[j].delay.value = adis->data->read_delay; + adis->xfer[j].delay.unit = SPI_DELAY_UNIT_USECS; + if (j < scan_count) + adis->xfer[j].tx_buf = &tx[j]; + if (j >= 1) + adis->xfer[j].rx_buf = &rx[j - 1]; + spi_message_add_tail(&adis->xfer[j], &adis->msg); + } + + chan = indio_dev->channels; + for (i = 0; i < indio_dev->num_channels; i++, chan++) { + if (!test_bit(chan->scan_index, scan_mask)) + continue; + if (chan->scan_type.storagebits == 32) + *tx++ = cpu_to_be16((chan->address + 2) << 8); + *tx++ = cpu_to_be16(chan->address << 8); + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(adis_update_scan_mode, IIO_ADISLIB); + +static irqreturn_t adis_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct adis *adis = iio_device_get_drvdata(indio_dev); + int ret; + + if (adis->data->has_paging) { + mutex_lock(&adis->state_lock); + if (adis->current_page != 0) { + adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID); + adis->tx[1] = 0; + ret = spi_write(adis->spi, adis->tx, 2); + if (ret) { + dev_err(&adis->spi->dev, "Failed to change device page: %d\n", ret); + mutex_unlock(&adis->state_lock); + goto irq_done; + } + + adis->current_page = 0; + } + } + + ret = spi_sync(adis->spi, &adis->msg); + if (adis->data->has_paging) + mutex_unlock(&adis->state_lock); + if (ret) { + dev_err(&adis->spi->dev, "Failed to read data: %d", ret); + goto irq_done; + } + + iio_push_to_buffers_with_timestamp(indio_dev, adis->buffer, + pf->timestamp); + +irq_done: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static void adis_buffer_cleanup(void *arg) +{ + struct adis *adis = arg; + + kfree(adis->buffer); + kfree(adis->xfer); +} + +/** + * devm_adis_setup_buffer_and_trigger() - Sets up buffer and trigger for + * the managed adis device + * @adis: The adis device + * @indio_dev: The IIO device + * @trigger_handler: Optional trigger handler, may be NULL. + * + * Returns 0 on success, a negative error code otherwise. + * + * This function sets up the buffer and trigger for a adis devices. If + * 'trigger_handler' is NULL the default trigger handler will be used. The + * default trigger handler will simply read the registers assigned to the + * currently active channels. + */ +int +devm_adis_setup_buffer_and_trigger(struct adis *adis, struct iio_dev *indio_dev, + irq_handler_t trigger_handler) +{ + int ret; + + if (!trigger_handler) + trigger_handler = adis_trigger_handler; + + ret = devm_iio_triggered_buffer_setup(&adis->spi->dev, indio_dev, + &iio_pollfunc_store_time, + trigger_handler, NULL); + if (ret) + return ret; + + if (adis->spi->irq) { + ret = devm_adis_probe_trigger(adis, indio_dev); + if (ret) + return ret; + } + + return devm_add_action_or_reset(&adis->spi->dev, adis_buffer_cleanup, + adis); +} +EXPORT_SYMBOL_NS_GPL(devm_adis_setup_buffer_and_trigger, IIO_ADISLIB); + |