--- /dev/null
+/*
+ * Driver for the Asahi Kasei EMD Corporation AK8974
+ * and Aichi Steel AMI305 magnetometer chips.
+ * Based on a patch from Samu Onkalo and the AK8975 IIO driver.
+ *
+ * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+ * Copyright (c) 2010 NVIDIA Corporation.
+ * Copyright (C) 2016 Linaro Ltd.
+ *
+ * Author: Samu Onkalo <samu.p.onkalo@nokia.com>
+ * Author: Linus Walleij <linus.walleij@linaro.org>
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h> /* For irq_get_irq_data() */
+#include <linux/completion.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+/*
+ * 16-bit registers are little-endian. LSB is at the address defined below
+ * and MSB is at the next higher address.
+ */
+
+/* These registers are common for AK8974 and AMI305 */
+#define AK8974_SELFTEST 0x0C
+#define AK8974_SELFTEST_IDLE 0x55
+#define AK8974_SELFTEST_OK 0xAA
+
+#define AK8974_INFO 0x0D
+
+#define AK8974_WHOAMI 0x0F
+#define AK8974_WHOAMI_VALUE_AMI305 0x47
+#define AK8974_WHOAMI_VALUE_AK8974 0x48
+
+#define AK8974_DATA_X 0x10
+#define AK8974_DATA_Y 0x12
+#define AK8974_DATA_Z 0x14
+#define AK8974_INT_SRC 0x16
+#define AK8974_STATUS 0x18
+#define AK8974_INT_CLEAR 0x1A
+#define AK8974_CTRL1 0x1B
+#define AK8974_CTRL2 0x1C
+#define AK8974_CTRL3 0x1D
+#define AK8974_INT_CTRL 0x1E
+#define AK8974_INT_THRES 0x26 /* Absolute any axis value threshold */
+#define AK8974_PRESET 0x30
+
+/* AK8974-specific offsets */
+#define AK8974_OFFSET_X 0x20
+#define AK8974_OFFSET_Y 0x22
+#define AK8974_OFFSET_Z 0x24
+/* AMI305-specific offsets */
+#define AMI305_OFFSET_X 0x6C
+#define AMI305_OFFSET_Y 0x72
+#define AMI305_OFFSET_Z 0x78
+
+/* Different temperature registers */
+#define AK8974_TEMP 0x31
+#define AMI305_TEMP 0x60
+
+#define AK8974_INT_X_HIGH BIT(7) /* Axis over +threshold */
+#define AK8974_INT_Y_HIGH BIT(6)
+#define AK8974_INT_Z_HIGH BIT(5)
+#define AK8974_INT_X_LOW BIT(4) /* Axis below -threshold */
+#define AK8974_INT_Y_LOW BIT(3)
+#define AK8974_INT_Z_LOW BIT(2)
+#define AK8974_INT_RANGE BIT(1) /* Range overflow (any axis) */
+
+#define AK8974_STATUS_DRDY BIT(6) /* Data ready */
+#define AK8974_STATUS_OVERRUN BIT(5) /* Data overrun */
+#define AK8974_STATUS_INT BIT(4) /* Interrupt occurred */
+
+#define AK8974_CTRL1_POWER BIT(7) /* 0 = standby; 1 = active */
+#define AK8974_CTRL1_RATE BIT(4) /* 0 = 10 Hz; 1 = 20 Hz */
+#define AK8974_CTRL1_FORCE_EN BIT(1) /* 0 = normal; 1 = force */
+#define AK8974_CTRL1_MODE2 BIT(0) /* 0 */
+
+#define AK8974_CTRL2_INT_EN BIT(4) /* 1 = enable interrupts */
+#define AK8974_CTRL2_DRDY_EN BIT(3) /* 1 = enable data ready signal */
+#define AK8974_CTRL2_DRDY_POL BIT(2) /* 1 = data ready active high */
+#define AK8974_CTRL2_RESDEF (AK8974_CTRL2_DRDY_POL)
+
+#define AK8974_CTRL3_RESET BIT(7) /* Software reset */
+#define AK8974_CTRL3_FORCE BIT(6) /* Start forced measurement */
+#define AK8974_CTRL3_SELFTEST BIT(4) /* Set selftest register */
+#define AK8974_CTRL3_RESDEF 0x00
+
+#define AK8974_INT_CTRL_XEN BIT(7) /* Enable interrupt for this axis */
+#define AK8974_INT_CTRL_YEN BIT(6)
+#define AK8974_INT_CTRL_ZEN BIT(5)
+#define AK8974_INT_CTRL_XYZEN (BIT(7)|BIT(6)|BIT(5))
+#define AK8974_INT_CTRL_POL BIT(3) /* 0 = active low; 1 = active high */
+#define AK8974_INT_CTRL_PULSE BIT(1) /* 0 = latched; 1 = pulse (50 usec) */
+#define AK8974_INT_CTRL_RESDEF (AK8974_INT_CTRL_XYZEN | AK8974_INT_CTRL_POL)
+
+/* The AMI305 has elaborate FW version and serial number registers */
+#define AMI305_VER 0xE8
+#define AMI305_SN 0xEA
+
+#define AK8974_MAX_RANGE 2048
+
+#define AK8974_POWERON_DELAY 50
+#define AK8974_ACTIVATE_DELAY 1
+#define AK8974_SELFTEST_DELAY 1
+/*
+ * Set the autosuspend to two orders of magnitude larger than the poweron
+ * delay to make sane reasonable power tradeoff savings (5 seconds in
+ * this case).
+ */
+#define AK8974_AUTOSUSPEND_DELAY 5000
+
+#define AK8974_MEASTIME 3
+
+#define AK8974_PWR_ON 1
+#define AK8974_PWR_OFF 0
+
+/**
+ * struct ak8974 - state container for the AK8974 driver
+ * @i2c: parent I2C client
+ * @orientation: mounting matrix, flipped axis etc
+ * @map: regmap to access the AK8974 registers over I2C
+ * @regs: the avdd and dvdd power regulators
+ * @name: the name of the part
+ * @variant: the whoami ID value (for selecting code paths)
+ * @lock: locks the magnetometer for exclusive use during a measurement
+ * @drdy_irq: uses the DRDY IRQ line
+ * @drdy_complete: completion for DRDY
+ * @drdy_active_low: the DRDY IRQ is active low
+ */
+struct ak8974 {
+ struct i2c_client *i2c;
+ struct iio_mount_matrix orientation;
+ struct regmap *map;
+ struct regulator_bulk_data regs[2];
+ const char *name;
+ u8 variant;
+ struct mutex lock;
+ bool drdy_irq;
+ struct completion drdy_complete;
+ bool drdy_active_low;
+};
+
+static const char ak8974_reg_avdd[] = "avdd";
+static const char ak8974_reg_dvdd[] = "dvdd";
+
+static int ak8974_set_power(struct ak8974 *ak8974, bool mode)
+{
+ int ret;
+ u8 val;
+
+ val = mode ? AK8974_CTRL1_POWER : 0;
+ val |= AK8974_CTRL1_FORCE_EN;
+ ret = regmap_write(ak8974->map, AK8974_CTRL1, val);
+ if (ret < 0)
+ return ret;
+
+ if (mode)
+ msleep(AK8974_ACTIVATE_DELAY);
+
+ return 0;
+}
+
+static int ak8974_reset(struct ak8974 *ak8974)
+{
+ int ret;
+
+ /* Power on to get register access. Sets CTRL1 reg to reset state */
+ ret = ak8974_set_power(ak8974, AK8974_PWR_ON);
+ if (ret)
+ return ret;
+ ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_RESDEF);
+ if (ret)
+ return ret;
+ ret = regmap_write(ak8974->map, AK8974_CTRL3, AK8974_CTRL3_RESDEF);
+ if (ret)
+ return ret;
+ ret = regmap_write(ak8974->map, AK8974_INT_CTRL,
+ AK8974_INT_CTRL_RESDEF);
+ if (ret)
+ return ret;
+
+ /* After reset, power off is default state */
+ return ak8974_set_power(ak8974, AK8974_PWR_OFF);
+}
+
+static int ak8974_configure(struct ak8974 *ak8974)
+{
+ int ret;
+
+ ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_DRDY_EN |
+ AK8974_CTRL2_INT_EN);
+ if (ret)
+ return ret;
+ ret = regmap_write(ak8974->map, AK8974_CTRL3, 0);
+ if (ret)
+ return ret;
+ ret = regmap_write(ak8974->map, AK8974_INT_CTRL, AK8974_INT_CTRL_POL);
+ if (ret)
+ return ret;
+
+ return regmap_write(ak8974->map, AK8974_PRESET, 0);
+}
+
+static int ak8974_trigmeas(struct ak8974 *ak8974)
+{
+ unsigned int clear;
+ u8 mask;
+ u8 val;
+ int ret;
+
+ /* Clear any previous measurement overflow status */
+ ret = regmap_read(ak8974->map, AK8974_INT_CLEAR, &clear);
+ if (ret)
+ return ret;
+
+ /* If we have a DRDY IRQ line, use it */
+ if (ak8974->drdy_irq) {
+ mask = AK8974_CTRL2_INT_EN |
+ AK8974_CTRL2_DRDY_EN |
+ AK8974_CTRL2_DRDY_POL;
+ val = AK8974_CTRL2_DRDY_EN;
+
+ if (!ak8974->drdy_active_low)
+ val |= AK8974_CTRL2_DRDY_POL;
+
+ init_completion(&ak8974->drdy_complete);
+ ret = regmap_update_bits(ak8974->map, AK8974_CTRL2,
+ mask, val);
+ if (ret)
+ return ret;
+ }
+
+ /* Force a measurement */
+ return regmap_update_bits(ak8974->map,
+ AK8974_CTRL3,
+ AK8974_CTRL3_FORCE,
+ AK8974_CTRL3_FORCE);
+}
+
+static int ak8974_await_drdy(struct ak8974 *ak8974)
+{
+ int timeout = 2;
+ unsigned int val;
+ int ret;
+
+ if (ak8974->drdy_irq) {
+ ret = wait_for_completion_timeout(&ak8974->drdy_complete,
+ 1 + msecs_to_jiffies(1000));
+ if (!ret) {
+ dev_err(&ak8974->i2c->dev,
+ "timeout waiting for DRDY IRQ\n");
+ return -ETIMEDOUT;
+ }
+ return 0;
+ }
+
+ /* Default delay-based poll loop */
+ do {
+ msleep(AK8974_MEASTIME);
+ ret = regmap_read(ak8974->map, AK8974_STATUS, &val);
+ if (ret < 0)
+ return ret;
+ if (val & AK8974_STATUS_DRDY)
+ return 0;
+ } while (--timeout);
+ if (!timeout) {
+ dev_err(&ak8974->i2c->dev,
+ "timeout waiting for DRDY\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int ak8974_getresult(struct ak8974 *ak8974, s16 *result)
+{
+ unsigned int src;
+ int ret;
+
+ ret = ak8974_await_drdy(ak8974);
+ if (ret)
+ return ret;
+ ret = regmap_read(ak8974->map, AK8974_INT_SRC, &src);
+ if (ret < 0)
+ return ret;
+
+ /* Out of range overflow! Strong magnet close? */
+ if (src & AK8974_INT_RANGE) {
+ dev_err(&ak8974->i2c->dev,
+ "range overflow in sensor\n");
+ return -ERANGE;
+ }
+
+ ret = regmap_bulk_read(ak8974->map, AK8974_DATA_X, result, 6);
+ if (ret)
+ return ret;
+
+ return ret;
+}
+
+static irqreturn_t ak8974_drdy_irq(int irq, void *d)
+{
+ struct ak8974 *ak8974 = d;
+
+ if (!ak8974->drdy_irq)
+ return IRQ_NONE;
+
+ /* TODO: timestamp here to get good measurement stamps */
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t ak8974_drdy_irq_thread(int irq, void *d)
+{
+ struct ak8974 *ak8974 = d;
+ unsigned int val;
+ int ret;
+
+ /* Check if this was a DRDY from us */
+ ret = regmap_read(ak8974->map, AK8974_STATUS, &val);
+ if (ret < 0) {
+ dev_err(&ak8974->i2c->dev, "error reading DRDY status\n");
+ return IRQ_HANDLED;
+ }
+ if (val & AK8974_STATUS_DRDY) {
+ /* Yes this was our IRQ */
+ complete(&ak8974->drdy_complete);
+ return IRQ_HANDLED;
+ }
+
+ /* We may be on a shared IRQ, let the next client check */
+ return IRQ_NONE;
+}
+
+static int ak8974_selftest(struct ak8974 *ak8974)
+{
+ struct device *dev = &ak8974->i2c->dev;
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);
+ if (ret)
+ return ret;
+ if (val != AK8974_SELFTEST_IDLE) {
+ dev_err(dev, "selftest not idle before test\n");
+ return -EIO;
+ }
+
+ /* Trigger self-test */
+ ret = regmap_update_bits(ak8974->map,
+ AK8974_CTRL3,
+ AK8974_CTRL3_SELFTEST,
+ AK8974_CTRL3_SELFTEST);
+ if (ret) {
+ dev_err(dev, "could not write CTRL3\n");
+ return ret;
+ }
+
+ msleep(AK8974_SELFTEST_DELAY);
+
+ ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);
+ if (ret)
+ return ret;
+ if (val != AK8974_SELFTEST_OK) {
+ dev_err(dev, "selftest result NOT OK (%02x)\n", val);
+ return -EIO;
+ }
+
+ ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);
+ if (ret)
+ return ret;
+ if (val != AK8974_SELFTEST_IDLE) {
+ dev_err(dev, "selftest not idle after test (%02x)\n", val);
+ return -EIO;
+ }
+ dev_dbg(dev, "passed self-test\n");
+
+ return 0;
+}
+
+static int ak8974_get_u16_val(struct ak8974 *ak8974, u8 reg, u16 *val)
+{
+ int ret;
+ u16 bulk;
+
+ ret = regmap_bulk_read(ak8974->map, reg, &bulk, 2);
+ if (ret)
+ return ret;
+ *val = le16_to_cpu(bulk);
+
+ return 0;
+}
+
+static int ak8974_detect(struct ak8974 *ak8974)
+{
+ unsigned int whoami;
+ const char *name;
+ int ret;
+ unsigned int fw;
+ u16 sn;
+
+ ret = regmap_read(ak8974->map, AK8974_WHOAMI, &whoami);
+ if (ret)
+ return ret;
+
+ switch (whoami) {
+ case AK8974_WHOAMI_VALUE_AMI305:
+ name = "ami305";
+ ret = regmap_read(ak8974->map, AMI305_VER, &fw);
+ if (ret)
+ return ret;
+ fw &= 0x7f; /* only bits 0 thru 6 valid */
+ ret = ak8974_get_u16_val(ak8974, AMI305_SN, &sn);
+ if (ret)
+ return ret;
+ dev_info(&ak8974->i2c->dev,
+ "detected %s, FW ver %02x, S/N: %04x\n",
+ name, fw, sn);
+ break;
+ case AK8974_WHOAMI_VALUE_AK8974:
+ name = "ak8974";
+ dev_info(&ak8974->i2c->dev, "detected AK8974\n");
+ break;
+ default:
+ dev_err(&ak8974->i2c->dev, "unsupported device (%02x) ",
+ whoami);
+ return -ENODEV;
+ }
+
+ ak8974->name = name;
+ ak8974->variant = whoami;
+
+ return 0;
+}
+
+static int ak8974_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2,
+ long mask)
+{
+ struct ak8974 *ak8974 = iio_priv(indio_dev);
+ s16 hw_values[3];
+ int ret = -EINVAL;
+
+ pm_runtime_get_sync(&ak8974->i2c->dev);
+ mutex_lock(&ak8974->lock);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (chan->address > 2) {
+ dev_err(&ak8974->i2c->dev, "faulty channel address\n");
+ ret = -EIO;
+ goto out_unlock;
+ }
+ ret = ak8974_trigmeas(ak8974);
+ if (ret)
+ goto out_unlock;
+ ret = ak8974_getresult(ak8974, hw_values);
+ if (ret)
+ goto out_unlock;
+
+ /*
+ * We read all axes and discard all but one, for optimized
+ * reading, use the triggered buffer.
+ */
+ *val = le16_to_cpu(hw_values[chan->address]);
+
+ ret = IIO_VAL_INT;
+ }
+
+ out_unlock:
+ mutex_unlock(&ak8974->lock);
+ pm_runtime_mark_last_busy(&ak8974->i2c->dev);
+ pm_runtime_put_autosuspend(&ak8974->i2c->dev);
+
+ return ret;
+}
+
+static void ak8974_fill_buffer(struct iio_dev *indio_dev)
+{
+ struct ak8974 *ak8974 = iio_priv(indio_dev);
+ int ret;
+ s16 hw_values[8]; /* Three axes + 64bit padding */
+
+ pm_runtime_get_sync(&ak8974->i2c->dev);
+ mutex_lock(&ak8974->lock);
+
+ ret = ak8974_trigmeas(ak8974);
+ if (ret) {
+ dev_err(&ak8974->i2c->dev, "error triggering measure\n");
+ goto out_unlock;
+ }
+ ret = ak8974_getresult(ak8974, hw_values);
+ if (ret) {
+ dev_err(&ak8974->i2c->dev, "error getting measures\n");
+ goto out_unlock;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, hw_values,
+ iio_get_time_ns(indio_dev));
+
+ out_unlock:
+ mutex_unlock(&ak8974->lock);
+ pm_runtime_mark_last_busy(&ak8974->i2c->dev);
+ pm_runtime_put_autosuspend(&ak8974->i2c->dev);
+}
+
+static irqreturn_t ak8974_handle_trigger(int irq, void *p)
+{
+ const struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+
+ ak8974_fill_buffer(indio_dev);
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_mount_matrix *
+ak8974_get_mount_matrix(const struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct ak8974 *ak8974 = iio_priv(indio_dev);
+
+ return &ak8974->orientation;
+}
+
+static const struct iio_chan_spec_ext_info ak8974_ext_info[] = {
+ IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8974_get_mount_matrix),
+ { },
+};
+
+#define AK8974_AXIS_CHANNEL(axis, index) \
+ { \
+ .type = IIO_MAGN, \
+ .modified = 1, \
+ .channel2 = IIO_MOD_##axis, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .ext_info = ak8974_ext_info, \
+ .address = index, \
+ .scan_index = index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_LE \
+ }, \
+ }
+
+static const struct iio_chan_spec ak8974_channels[] = {
+ AK8974_AXIS_CHANNEL(X, 0),
+ AK8974_AXIS_CHANNEL(Y, 1),
+ AK8974_AXIS_CHANNEL(Z, 2),
+ IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+static const unsigned long ak8974_scan_masks[] = { 0x7, 0 };
+
+static const struct iio_info ak8974_info = {
+ .read_raw = &ak8974_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static bool ak8974_writeable_reg(struct device *dev, unsigned int reg)
+{
+ struct i2c_client *i2c = to_i2c_client(dev);
+ struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
+ struct ak8974 *ak8974 = iio_priv(indio_dev);
+
+ switch (reg) {
+ case AK8974_CTRL1:
+ case AK8974_CTRL2:
+ case AK8974_CTRL3:
+ case AK8974_INT_CTRL:
+ case AK8974_INT_THRES:
+ case AK8974_INT_THRES + 1:
+ case AK8974_PRESET:
+ case AK8974_PRESET + 1:
+ return true;
+ case AK8974_OFFSET_X:
+ case AK8974_OFFSET_X + 1:
+ case AK8974_OFFSET_Y:
+ case AK8974_OFFSET_Y + 1:
+ case AK8974_OFFSET_Z:
+ case AK8974_OFFSET_Z + 1:
+ if (ak8974->variant == AK8974_WHOAMI_VALUE_AK8974)
+ return true;
+ return false;
+ case AMI305_OFFSET_X:
+ case AMI305_OFFSET_X + 1:
+ case AMI305_OFFSET_Y:
+ case AMI305_OFFSET_Y + 1:
+ case AMI305_OFFSET_Z:
+ case AMI305_OFFSET_Z + 1:
+ if (ak8974->variant == AK8974_WHOAMI_VALUE_AMI305)
+ return true;
+ return false;
+ default:
+ return false;
+ }
+}
+
+static const struct regmap_config ak8974_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = 0xff,
+ .writeable_reg = ak8974_writeable_reg,
+};
+
+static int ak8974_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct iio_dev *indio_dev;
+ struct ak8974 *ak8974;
+ unsigned long irq_trig;
+ int irq = i2c->irq;
+ int ret;
+
+ /* Register with IIO */
+ indio_dev = devm_iio_device_alloc(&i2c->dev, sizeof(*ak8974));
+ if (indio_dev == NULL)
+ return -ENOMEM;
+
+ ak8974 = iio_priv(indio_dev);
+ i2c_set_clientdata(i2c, indio_dev);
+ ak8974->i2c = i2c;
+ mutex_init(&ak8974->lock);
+
+ ret = of_iio_read_mount_matrix(&i2c->dev,
+ "mount-matrix",
+ &ak8974->orientation);
+ if (ret)
+ return ret;
+
+ ak8974->regs[0].supply = ak8974_reg_avdd;
+ ak8974->regs[1].supply = ak8974_reg_dvdd;
+
+ ret = devm_regulator_bulk_get(&i2c->dev,
+ ARRAY_SIZE(ak8974->regs),
+ ak8974->regs);
+ if (ret < 0) {
+ dev_err(&i2c->dev, "cannot get regulators\n");
+ return ret;
+ }
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
+ if (ret < 0) {
+ dev_err(&i2c->dev, "cannot enable regulators\n");
+ return ret;
+ }
+
+ /* Take runtime PM online */
+ pm_runtime_get_noresume(&i2c->dev);
+ pm_runtime_set_active(&i2c->dev);
+ pm_runtime_enable(&i2c->dev);
+
+ ak8974->map = devm_regmap_init_i2c(i2c, &ak8974_regmap_config);
+ if (IS_ERR(ak8974->map)) {
+ dev_err(&i2c->dev, "failed to allocate register map\n");
+ return PTR_ERR(ak8974->map);
+ }
+
+ ret = ak8974_set_power(ak8974, AK8974_PWR_ON);
+ if (ret) {
+ dev_err(&i2c->dev, "could not power on\n");
+ goto power_off;
+ }
+
+ ret = ak8974_detect(ak8974);
+ if (ret) {
+ dev_err(&i2c->dev, "neither AK8974 nor AMI305 found\n");
+ goto power_off;
+ }
+
+ ret = ak8974_selftest(ak8974);
+ if (ret)
+ dev_err(&i2c->dev, "selftest failed (continuing anyway)\n");
+
+ ret = ak8974_reset(ak8974);
+ if (ret) {
+ dev_err(&i2c->dev, "AK8974 reset failed\n");
+ goto power_off;
+ }
+
+ pm_runtime_set_autosuspend_delay(&i2c->dev,
+ AK8974_AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(&i2c->dev);
+ pm_runtime_put(&i2c->dev);
+
+ indio_dev->dev.parent = &i2c->dev;
+ indio_dev->channels = ak8974_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ak8974_channels);
+ indio_dev->info = &ak8974_info;
+ indio_dev->available_scan_masks = ak8974_scan_masks;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->name = ak8974->name;
+
+ ret = iio_triggered_buffer_setup(indio_dev, NULL,
+ ak8974_handle_trigger,
+ NULL);
+ if (ret) {
+ dev_err(&i2c->dev, "triggered buffer setup failed\n");
+ goto disable_pm;
+ }
+
+ /* If we have a valid DRDY IRQ, make use of it */
+ if (irq > 0) {
+ irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
+ if (irq_trig == IRQF_TRIGGER_RISING) {
+ dev_info(&i2c->dev, "enable rising edge DRDY IRQ\n");
+ } else if (irq_trig == IRQF_TRIGGER_FALLING) {
+ ak8974->drdy_active_low = true;
+ dev_info(&i2c->dev, "enable falling edge DRDY IRQ\n");
+ } else {
+ irq_trig = IRQF_TRIGGER_RISING;
+ }
+ irq_trig |= IRQF_ONESHOT;
+ irq_trig |= IRQF_SHARED;
+
+ ret = devm_request_threaded_irq(&i2c->dev,
+ irq,
+ ak8974_drdy_irq,
+ ak8974_drdy_irq_thread,
+ irq_trig,
+ ak8974->name,
+ ak8974);
+ if (ret) {
+ dev_err(&i2c->dev, "unable to request DRDY IRQ "
+ "- proceeding without IRQ\n");
+ goto no_irq;
+ }
+ ak8974->drdy_irq = true;
+ }
+
+no_irq:
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&i2c->dev, "device register failed\n");
+ goto cleanup_buffer;
+ }
+
+ return 0;
+
+cleanup_buffer:
+ iio_triggered_buffer_cleanup(indio_dev);
+disable_pm:
+ pm_runtime_put_noidle(&i2c->dev);
+ pm_runtime_disable(&i2c->dev);
+ ak8974_set_power(ak8974, AK8974_PWR_OFF);
+power_off:
+ regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
+
+ return ret;
+}
+
+static int __exit ak8974_remove(struct i2c_client *i2c)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
+ struct ak8974 *ak8974 = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+ pm_runtime_get_sync(&i2c->dev);
+ pm_runtime_put_noidle(&i2c->dev);
+ pm_runtime_disable(&i2c->dev);
+ ak8974_set_power(ak8974, AK8974_PWR_OFF);
+ regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int ak8974_runtime_suspend(struct device *dev)
+{
+ struct ak8974 *ak8974 =
+ iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+ ak8974_set_power(ak8974, AK8974_PWR_OFF);
+ regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
+
+ return 0;
+}
+
+static int ak8974_runtime_resume(struct device *dev)
+{
+ struct ak8974 *ak8974 =
+ iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
+ if (ret)
+ return ret;
+ msleep(AK8974_POWERON_DELAY);
+ ret = ak8974_set_power(ak8974, AK8974_PWR_ON);
+ if (ret)
+ goto out_regulator_disable;
+
+ ret = ak8974_configure(ak8974);
+ if (ret)
+ goto out_disable_power;
+
+ return 0;
+
+out_disable_power:
+ ak8974_set_power(ak8974, AK8974_PWR_OFF);
+out_regulator_disable:
+ regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);
+
+ return ret;
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops ak8974_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(ak8974_runtime_suspend,
+ ak8974_runtime_resume, NULL)
+};
+
+static const struct i2c_device_id ak8974_id[] = {
+ {"ami305", 0 },
+ {"ak8974", 0 },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, ak8974_id);
+
+static const struct of_device_id ak8974_of_match[] = {
+ { .compatible = "asahi-kasei,ak8974", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ak8974_of_match);
+
+static struct i2c_driver ak8974_driver = {
+ .driver = {
+ .name = "ak8974",
+ .owner = THIS_MODULE,
+ .pm = &ak8974_dev_pm_ops,
+ .of_match_table = of_match_ptr(ak8974_of_match),
+ },
+ .probe = ak8974_probe,
+ .remove = __exit_p(ak8974_remove),
+ .id_table = ak8974_id,
+};
+module_i2c_driver(ak8974_driver);
+
+MODULE_DESCRIPTION("AK8974 and AMI305 3-axis magnetometer driver");
+MODULE_AUTHOR("Samu Onkalo");
+MODULE_AUTHOR("Linus Walleij");
+MODULE_LICENSE("GPL v2");
projects / deliverable / linux.git / blobdiff