--- /dev/null
+/*
+ * Common library for ADIS16XXX devices
+ *
+ * Copyright 2012 Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/module.h>
+#include <asm/unaligned.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/imu/adis.h>
+
+#define ADIS_MSC_CTRL_DATA_RDY_EN BIT(2)
+#define ADIS_MSC_CTRL_DATA_RDY_POL_HIGH BIT(1)
+#define ADIS_MSC_CTRL_DATA_RDY_DIO2 BIT(0)
+#define ADIS_GLOB_CMD_SW_RESET BIT(7)
+
+int adis_write_reg(struct adis *adis, unsigned int reg,
+ unsigned int value, unsigned int size)
+{
+ unsigned int page = reg / ADIS_PAGE_SIZE;
+ int ret, i;
+ struct spi_message msg;
+ struct spi_transfer xfers[] = {
+ {
+ .tx_buf = adis->tx,
+ .bits_per_word = 8,
+ .len = 2,
+ .cs_change = 1,
+ .delay_usecs = adis->data->write_delay,
+ }, {
+ .tx_buf = adis->tx + 2,
+ .bits_per_word = 8,
+ .len = 2,
+ .cs_change = 1,
+ .delay_usecs = adis->data->write_delay,
+ }, {
+ .tx_buf = adis->tx + 4,
+ .bits_per_word = 8,
+ .len = 2,
+ .cs_change = 1,
+ .delay_usecs = adis->data->write_delay,
+ }, {
+ .tx_buf = adis->tx + 6,
+ .bits_per_word = 8,
+ .len = 2,
+ .delay_usecs = adis->data->write_delay,
+ }, {
+ .tx_buf = adis->tx + 8,
+ .bits_per_word = 8,
+ .len = 2,
+ .delay_usecs = adis->data->write_delay,
+ },
+ };
+
+ mutex_lock(&adis->txrx_lock);
+
+ spi_message_init(&msg);
+
+ if (adis->current_page != page) {
+ adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID);
+ adis->tx[1] = page;
+ spi_message_add_tail(&xfers[0], &msg);
+ }
+
+ switch (size) {
+ case 4:
+ adis->tx[8] = ADIS_WRITE_REG(reg + 3);
+ adis->tx[9] = (value >> 24) & 0xff;
+ adis->tx[6] = ADIS_WRITE_REG(reg + 2);
+ adis->tx[7] = (value >> 16) & 0xff;
+ case 2:
+ adis->tx[4] = ADIS_WRITE_REG(reg + 1);
+ adis->tx[5] = (value >> 8) & 0xff;
+ case 1:
+ adis->tx[2] = ADIS_WRITE_REG(reg);
+ adis->tx[3] = value & 0xff;
+ break;
+ default:
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ xfers[size].cs_change = 0;
+
+ for (i = 1; i <= size; i++)
+ spi_message_add_tail(&xfers[i], &msg);
+
+ ret = spi_sync(adis->spi, &msg);
+ if (ret) {
+ dev_err(&adis->spi->dev, "Failed to write register 0x%02X: %d\n",
+ reg, ret);
+ } else {
+ adis->current_page = page;
+ }
+
+out_unlock:
+ mutex_unlock(&adis->txrx_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(adis_write_reg);
+
+/**
+ * adis_read_reg() - read 2 bytes from a 16-bit register
+ * @adis: The adis device
+ * @reg: The address of the lower of the two registers
+ * @val: The value read back from the device
+ */
+int adis_read_reg(struct adis *adis, unsigned int reg,
+ unsigned int *val, unsigned int size)
+{
+ unsigned int page = reg / ADIS_PAGE_SIZE;
+ struct spi_message msg;
+ int ret;
+ struct spi_transfer xfers[] = {
+ {
+ .tx_buf = adis->tx,
+ .bits_per_word = 8,
+ .len = 2,
+ .cs_change = 1,
+ .delay_usecs = adis->data->write_delay,
+ }, {
+ .tx_buf = adis->tx + 2,
+ .bits_per_word = 8,
+ .len = 2,
+ .cs_change = 1,
+ .delay_usecs = adis->data->read_delay,
+ }, {
+ .tx_buf = adis->tx + 4,
+ .rx_buf = adis->rx,
+ .bits_per_word = 8,
+ .len = 2,
+ .cs_change = 1,
+ .delay_usecs = adis->data->read_delay,
+ }, {
+ .rx_buf = adis->rx + 2,
+ .bits_per_word = 8,
+ .len = 2,
+ .delay_usecs = adis->data->read_delay,
+ },
+ };
+
+ mutex_lock(&adis->txrx_lock);
+ spi_message_init(&msg);
+
+ if (adis->current_page != page) {
+ adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID);
+ adis->tx[1] = page;
+ spi_message_add_tail(&xfers[0], &msg);
+ }
+
+ switch (size) {
+ case 4:
+ adis->tx[2] = ADIS_READ_REG(reg + 2);
+ adis->tx[3] = 0;
+ spi_message_add_tail(&xfers[1], &msg);
+ case 2:
+ adis->tx[4] = ADIS_READ_REG(reg);
+ adis->tx[5] = 0;
+ spi_message_add_tail(&xfers[2], &msg);
+ spi_message_add_tail(&xfers[3], &msg);
+ break;
+ default:
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ ret = spi_sync(adis->spi, &msg);
+ if (ret) {
+ dev_err(&adis->spi->dev, "Failed to read register 0x%02X: %d\n",
+ reg, ret);
+ goto out_unlock;
+ } else {
+ adis->current_page = page;
+ }
+
+ switch (size) {
+ case 4:
+ *val = get_unaligned_be32(adis->rx);
+ break;
+ case 2:
+ *val = get_unaligned_be16(adis->rx + 2);
+ break;
+ }
+
+out_unlock:
+ mutex_unlock(&adis->txrx_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(adis_read_reg);
+
+#ifdef CONFIG_DEBUG_FS
+
+int adis_debugfs_reg_access(struct iio_dev *indio_dev,
+ unsigned int reg, unsigned int writeval, unsigned int *readval)
+{
+ struct adis *adis = iio_device_get_drvdata(indio_dev);
+
+ if (readval) {
+ uint16_t val16;
+ int ret;
+
+ ret = adis_read_reg_16(adis, reg, &val16);
+ *readval = val16;
+
+ return ret;
+ } else {
+ return adis_write_reg_16(adis, reg, writeval);
+ }
+}
+EXPORT_SYMBOL(adis_debugfs_reg_access);
+
+#endif
+
+/**
+ * adis_enable_irq() - Enable or disable data ready IRQ
+ * @adis: The adis device
+ * @enable: Whether to enable the IRQ
+ *
+ * Returns 0 on success, negative error code otherwise
+ */
+int adis_enable_irq(struct adis *adis, bool enable)
+{
+ int ret = 0;
+ uint16_t msc;
+
+ if (adis->data->enable_irq)
+ return adis->data->enable_irq(adis, enable);
+
+ ret = adis_read_reg_16(adis, adis->data->msc_ctrl_reg, &msc);
+ if (ret)
+ goto error_ret;
+
+ msc |= ADIS_MSC_CTRL_DATA_RDY_POL_HIGH;
+ msc &= ~ADIS_MSC_CTRL_DATA_RDY_DIO2;
+ if (enable)
+ msc |= ADIS_MSC_CTRL_DATA_RDY_EN;
+ else
+ msc &= ~ADIS_MSC_CTRL_DATA_RDY_EN;
+
+ ret = adis_write_reg_16(adis, adis->data->msc_ctrl_reg, msc);
+
+error_ret:
+ return ret;
+}
+EXPORT_SYMBOL(adis_enable_irq);
+
+/**
+ * adis_check_status() - Check the device for error conditions
+ * @adis: The adis device
+ *
+ * Returns 0 on success, a negative error code otherwise
+ */
+int adis_check_status(struct adis *adis)
+{
+ uint16_t status;
+ int ret;
+ int i;
+
+ ret = adis_read_reg_16(adis, adis->data->diag_stat_reg, &status);
+ if (ret < 0)
+ return ret;
+
+ status &= adis->data->status_error_mask;
+
+ if (status == 0)
+ return 0;
+
+ for (i = 0; i < 16; ++i) {
+ if (status & BIT(i)) {
+ dev_err(&adis->spi->dev, "%s.\n",
+ adis->data->status_error_msgs[i]);
+ }
+ }
+
+ return -EIO;
+}
+EXPORT_SYMBOL_GPL(adis_check_status);
+
+/**
+ * adis_reset() - Reset the device
+ * @adis: The adis device
+ *
+ * Returns 0 on success, a negative error code otherwise
+ */
+int adis_reset(struct adis *adis)
+{
+ int ret;
+
+ ret = adis_write_reg_8(adis, adis->data->glob_cmd_reg,
+ ADIS_GLOB_CMD_SW_RESET);
+ if (ret)
+ dev_err(&adis->spi->dev, "Failed to reset device: %d\n", ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(adis_reset);
+
+static int adis_self_test(struct adis *adis)
+{
+ int ret;
+
+ ret = adis_write_reg_16(adis, adis->data->msc_ctrl_reg,
+ adis->data->self_test_mask);
+ if (ret) {
+ dev_err(&adis->spi->dev, "Failed to initiate self test: %d\n",
+ ret);
+ return ret;
+ }
+
+ msleep(adis->data->startup_delay);
+
+ return adis_check_status(adis);
+}
+
+/**
+ * adis_inital_startup() - Performs device self-test
+ * @adis: The adis device
+ *
+ * Returns 0 if the device is operational, a negative error code otherwise.
+ *
+ * This function should be called early on in the device initialization sequence
+ * to ensure that the device is in a sane and known state and that it is usable.
+ */
+int adis_initial_startup(struct adis *adis)
+{
+ int ret;
+
+ ret = adis_self_test(adis);
+ if (ret) {
+ dev_err(&adis->spi->dev, "Self-test failed, trying reset.\n");
+ adis_reset(adis);
+ msleep(adis->data->startup_delay);
+ ret = adis_self_test(adis);
+ if (ret) {
+ dev_err(&adis->spi->dev, "Second self-test failed, giving up.\n");
+ return ret;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(adis_initial_startup);
+
+/**
+ * adis_single_conversion() - Performs a single sample conversion
+ * @indio_dev: The IIO device
+ * @chan: The IIO channel
+ * @error_mask: Mask for the error bit
+ * @val: Result of the conversion
+ *
+ * Returns IIO_VAL_INT on success, a negative error code otherwise.
+ *
+ * The function performs a single conversion on a given channel and post
+ * processes the value accordingly to the channel spec. If a error_mask is given
+ * the function will check if the mask is set in the returned raw value. If it
+ * is set the function will perform a self-check. If the device does not report
+ * a error bit in the channels raw value set error_mask to 0.
+ */
+int adis_single_conversion(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, unsigned int error_mask, int *val)
+{
+ struct adis *adis = iio_device_get_drvdata(indio_dev);
+ unsigned int uval;
+ int ret;
+
+ mutex_lock(&indio_dev->mlock);
+
+ ret = adis_read_reg(adis, chan->address, &uval,
+ chan->scan_type.storagebits / 8);
+ if (ret)
+ goto err_unlock;
+
+ if (uval & error_mask) {
+ ret = adis_check_status(adis);
+ if (ret)
+ goto err_unlock;
+ }
+
+ if (chan->scan_type.sign == 's')
+ *val = sign_extend32(uval, chan->scan_type.realbits - 1);
+ else
+ *val = uval & ((1 << chan->scan_type.realbits) - 1);
+
+ ret = IIO_VAL_INT;
+err_unlock:
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(adis_single_conversion);
+
+/**
+ * adis_init() - Initialize adis device structure
+ * @adis: The adis device
+ * @indio_dev: The iio device
+ * @spi: The spi device
+ * @data: Chip specific data
+ *
+ * Returns 0 on success, a negative error code otherwise.
+ *
+ * This function must be called, before any other adis helper function may be
+ * called.
+ */
+int adis_init(struct adis *adis, struct iio_dev *indio_dev,
+ struct spi_device *spi, const struct adis_data *data)
+{
+ mutex_init(&adis->txrx_lock);
+ adis->spi = spi;
+ adis->data = data;
+ iio_device_set_drvdata(indio_dev, adis);
+
+ if (data->has_paging) {
+ /* Need to set the page before first read/write */
+ adis->current_page = -1;
+ } else {
+ /* Page will always be 0 */
+ adis->current_page = 0;
+ }
+
+ return adis_enable_irq(adis, false);
+}
+EXPORT_SYMBOL_GPL(adis_init);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Common library code for ADIS16XXX devices");
Code Review / kvmfornfv.git / blobdiff