[PATCH 08/12] iio: imu: inv_icm42600: add device interrupt trigger

From: Jean-Baptiste Maneyrol
Date: Thu May 07 2020 - 10:44:00 EST


Add INT1 interrupt support and use it as an iio trigger.
Support interrupt edge and level, active high or low.
Push-pull configuration only.

Trigger enables FIFO and will be useful with buffer support.

Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@xxxxxxxxxxxxxx>
---
drivers/iio/imu/inv_icm42600/Kconfig | 1 +
drivers/iio/imu/inv_icm42600/Makefile | 1 +
drivers/iio/imu/inv_icm42600/inv_icm42600.h | 8 +-
.../iio/imu/inv_icm42600/inv_icm42600_core.c | 19 +-
.../iio/imu/inv_icm42600/inv_icm42600_i2c.c | 2 +-
.../iio/imu/inv_icm42600/inv_icm42600_spi.c | 2 +-
.../imu/inv_icm42600/inv_icm42600_trigger.c | 177 ++++++++++++++++++
7 files changed, 206 insertions(+), 4 deletions(-)
create mode 100644 drivers/iio/imu/inv_icm42600/inv_icm42600_trigger.c

diff --git a/drivers/iio/imu/inv_icm42600/Kconfig b/drivers/iio/imu/inv_icm42600/Kconfig
index 22390a72f0a3..7b3eaeb2aa4a 100644
--- a/drivers/iio/imu/inv_icm42600/Kconfig
+++ b/drivers/iio/imu/inv_icm42600/Kconfig
@@ -2,6 +2,7 @@

config INV_ICM42600
tristate
+ select IIO_TRIGGER

config INV_ICM42600_I2C
tristate "InvenSense ICM-426xx I2C driver"
diff --git a/drivers/iio/imu/inv_icm42600/Makefile b/drivers/iio/imu/inv_icm42600/Makefile
index 48965824f00c..e1f2aacbe888 100644
--- a/drivers/iio/imu/inv_icm42600/Makefile
+++ b/drivers/iio/imu/inv_icm42600/Makefile
@@ -5,6 +5,7 @@ inv-icm42600-y += inv_icm42600_core.o
inv-icm42600-y += inv_icm42600_gyro.o
inv-icm42600-y += inv_icm42600_accel.o
inv-icm42600-y += inv_icm42600_temp.o
+inv-icm42600-y += inv_icm42600_trigger.o

obj-$(CONFIG_INV_ICM42600_I2C) += inv-icm42600-i2c.o
inv-icm42600-i2c-y += inv_icm42600_i2c.o
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600.h b/drivers/iio/imu/inv_icm42600/inv_icm42600.h
index bc963b3d1800..175c1f67faee 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600.h
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600.h
@@ -13,6 +13,7 @@
#include <linux/regulator/consumer.h>
#include <linux/pm.h>
#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>

enum inv_icm42600_chip {
INV_CHIP_ICM42600,
@@ -122,6 +123,7 @@ struct inv_icm42600_suspended {
* @suspended: suspended sensors configuration.
* @indio_gyro: gyroscope IIO device.
* @indio_accel: accelerometer IIO device.
+ * @trigger: device internal interrupt trigger
*/
struct inv_icm42600_state {
struct mutex lock;
@@ -135,6 +137,7 @@ struct inv_icm42600_state {
struct inv_icm42600_suspended suspended;
struct iio_dev *indio_gyro;
struct iio_dev *indio_accel;
+ struct iio_trigger *trigger;
};

/* Virtual register addresses: @bank on MSB (4 upper bits), @address on LSB */
@@ -370,11 +373,14 @@ int inv_icm42600_set_temp_conf(struct inv_icm42600_state *st, bool enable,
int inv_icm42600_debugfs_reg(struct iio_dev *indio_dev, unsigned int reg,
unsigned int writeval, unsigned int *readval);

-int inv_icm42600_core_probe(struct regmap *regmap, int chip,
+int inv_icm42600_core_probe(struct regmap *regmap, int chip, int irq,
inv_icm42600_bus_setup bus_setup);

int inv_icm42600_gyro_init(struct inv_icm42600_state *st);

int inv_icm42600_accel_init(struct inv_icm42600_state *st);

+int inv_icm42600_trigger_init(struct inv_icm42600_state *st, int irq,
+ int irq_type);
+
#endif
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
index 4e33f263d3ea..1102c54396e3 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
@@ -447,11 +447,13 @@ static void inv_icm42600_disable_pm(void *_data)
pm_runtime_disable(dev);
}

-int inv_icm42600_core_probe(struct regmap *regmap, int chip,
+int inv_icm42600_core_probe(struct regmap *regmap, int chip, int irq,
inv_icm42600_bus_setup bus_setup)
{
struct device *dev = regmap_get_device(regmap);
struct inv_icm42600_state *st;
+ struct irq_data *irq_desc;
+ int irq_type;
int ret;

BUILD_BUG_ON(ARRAY_SIZE(inv_icm42600_hw) != INV_CHIP_NB);
@@ -460,6 +462,16 @@ int inv_icm42600_core_probe(struct regmap *regmap, int chip,
return -ENODEV;
}

+ /* get irq data, set trigger falling by default */
+ irq_desc = irq_get_irq_data(irq);
+ if (!irq_desc) {
+ dev_err(dev, "could not find IRQ %d\n", irq);
+ return -EINVAL;
+ }
+ irq_type = irqd_get_trigger_type(irq_desc);
+ if (!irq_type)
+ irq_type = IRQF_TRIGGER_FALLING;
+
st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
if (!st)
return -ENOMEM;
@@ -503,6 +515,11 @@ int inv_icm42600_core_probe(struct regmap *regmap, int chip,
if (ret)
return ret;

+ /* setup interrupt trigger */
+ ret = inv_icm42600_trigger_init(st, irq, irq_type);
+ if (ret)
+ return ret;
+
/* create and init gyroscope iio device */
ret = inv_icm42600_gyro_init(st);
if (ret)
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
index b61f993beacf..b1478ece43f6 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
@@ -70,7 +70,7 @@ static int inv_icm42600_probe(struct i2c_client *client,
if (IS_ERR(regmap))
return PTR_ERR(regmap);

- return inv_icm42600_core_probe(regmap, chip,
+ return inv_icm42600_core_probe(regmap, chip, client->irq,
inv_icm42600_i2c_bus_setup);
}

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c
index 835ced68a3a3..ec784f9e3c2c 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c
@@ -70,7 +70,7 @@ static int inv_icm42600_probe(struct spi_device *spi)
if (IS_ERR(regmap))
return PTR_ERR(regmap);

- return inv_icm42600_core_probe(regmap, chip,
+ return inv_icm42600_core_probe(regmap, chip, spi->irq,
inv_icm42600_spi_bus_setup);
}

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_trigger.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_trigger.c
new file mode 100644
index 000000000000..7a5e76305f0b
--- /dev/null
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_trigger.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2020 Invensense, Inc.
+ */
+
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+
+#include "inv_icm42600.h"
+
+static irqreturn_t inv_icm42600_trigger_timestamp(int irq, void *_data)
+{
+ struct inv_icm42600_state *st = _data;
+
+ if (st->indio_gyro)
+ iio_pollfunc_store_time(irq, st->indio_gyro->pollfunc);
+ if (st->indio_accel)
+ iio_pollfunc_store_time(irq, st->indio_accel->pollfunc);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t inv_icm42600_trigger_int_handler(int irq, void *_data)
+{
+ struct inv_icm42600_state *st = _data;
+ struct device *dev = regmap_get_device(st->map);
+ unsigned int status;
+ int ret;
+
+ mutex_lock(&st->lock);
+
+ ret = regmap_read(st->map, INV_ICM42600_REG_INT_STATUS, &status);
+ if (ret)
+ goto out_unlock;
+ dev_dbg(dev, "int_status = %#02x\n", status);
+
+ /* FIFO full */
+ if (status & INV_ICM42600_INT_STATUS_FIFO_FULL)
+ dev_warn(dev, "FIFO full data lost!\n");
+
+ /* FIFO threshold reached */
+ if (status & INV_ICM42600_INT_STATUS_FIFO_THS)
+ iio_trigger_poll_chained(st->trigger);
+
+out_unlock:
+ mutex_unlock(&st->lock);
+ return IRQ_HANDLED;
+}
+
+static int inv_icm42600_trigger_set_state(struct iio_trigger *trig, bool state)
+{
+ struct inv_icm42600_state *st = iio_trigger_get_drvdata(trig);
+ unsigned int val;
+ uint16_t dummy;
+ int ret;
+
+ mutex_lock(&st->lock);
+
+ /*
+ * IIO buffers preenable and postdisable are managing power on/off.
+ * update_scan_mode is setting data FIFO enabled.
+ */
+ if (state) {
+ /* set FIFO threshold interrupt */
+ val = INV_ICM42600_INT_SOURCE0_FIFO_THS_INT1_EN;
+ ret = regmap_update_bits(st->map, INV_ICM42600_REG_INT_SOURCE0,
+ val, val);
+ if (ret)
+ goto out_unlock;
+ /* flush FIFO data */
+ ret = regmap_write(st->map, INV_ICM42600_REG_SIGNAL_PATH_RESET,
+ INV_ICM42600_SIGNAL_PATH_RESET_FIFO_FLUSH);
+ if (ret)
+ goto out_unlock;
+ /* set FIFO in streaming mode */
+ ret = regmap_write(st->map, INV_ICM42600_REG_FIFO_CONFIG,
+ INV_ICM42600_FIFO_CONFIG_STREAM);
+ if (ret)
+ goto out_unlock;
+ /* workaround: dummy read of FIFO count */
+ ret = regmap_bulk_read(st->map, INV_ICM42600_REG_FIFO_COUNT,
+ &dummy, sizeof(dummy));
+ } else {
+ /* set FIFO in bypass mode */
+ ret = regmap_write(st->map, INV_ICM42600_REG_FIFO_CONFIG,
+ INV_ICM42600_FIFO_CONFIG_BYPASS);
+ if (ret)
+ goto out_unlock;
+ /* flush FIFO data */
+ ret = regmap_write(st->map, INV_ICM42600_REG_SIGNAL_PATH_RESET,
+ INV_ICM42600_SIGNAL_PATH_RESET_FIFO_FLUSH);
+ if (ret)
+ goto out_unlock;
+ /* disable FIFO threshold interrupt */
+ val = INV_ICM42600_INT_SOURCE0_FIFO_THS_INT1_EN;
+ ret = regmap_update_bits(st->map, INV_ICM42600_REG_INT_SOURCE0,
+ val, 0);
+ }
+
+out_unlock:
+ mutex_unlock(&st->lock);
+ return ret;
+}
+
+static int inv_icm42600_trigger_validate(struct iio_trigger *trig,
+ struct iio_dev *indio_dev)
+{
+ struct inv_icm42600_state *st = iio_trigger_get_drvdata(trig);
+
+ if (iio_device_get_drvdata(indio_dev) != st)
+ return -ENODEV;
+
+ return 0;
+}
+
+static const struct iio_trigger_ops inv_icm42600_trigger_ops = {
+ .set_trigger_state = &inv_icm42600_trigger_set_state,
+ .validate_device = &inv_icm42600_trigger_validate,
+};
+
+int inv_icm42600_trigger_init(struct inv_icm42600_state *st, int irq,
+ int irq_type)
+{
+ struct device *dev = regmap_get_device(st->map);
+ unsigned int val;
+ int ret;
+
+ st->trigger = devm_iio_trigger_alloc(dev, "%s-dev", st->name);
+ if (!st->trigger)
+ return -ENOMEM;
+
+ st->trigger->dev.parent = dev;
+ st->trigger->ops = &inv_icm42600_trigger_ops;
+ iio_trigger_set_drvdata(st->trigger, st);
+
+ /* configure INT1 with correct mode */
+ /* falling or both-edge */
+ if (irq_type & IRQF_TRIGGER_FALLING) {
+ val = INV_ICM42600_INT_CONFIG_INT1_ACTIVE_LOW;
+ } else if (irq_type == IRQF_TRIGGER_RISING) {
+ val = INV_ICM42600_INT_CONFIG_INT1_ACTIVE_HIGH;
+ } else if (irq_type == IRQF_TRIGGER_LOW) {
+ val = INV_ICM42600_INT_CONFIG_INT1_ACTIVE_LOW |
+ INV_ICM42600_INT_CONFIG_INT1_LATCHED;
+ } else if (irq_type == IRQF_TRIGGER_HIGH) {
+ val = INV_ICM42600_INT_CONFIG_INT1_ACTIVE_LOW |
+ INV_ICM42600_INT_CONFIG_INT1_LATCHED;
+ } else {
+ dev_err(dev, "invalid interrupt type %#x\n", irq_type);
+ return -EINVAL;
+ }
+ val |= INV_ICM42600_INT_CONFIG_INT1_PUSH_PULL;
+ ret = regmap_write(st->map, INV_ICM42600_REG_INT_CONFIG, val);
+ if (ret)
+ return ret;
+
+ /* Deassert async reset for proper INT pin operation (cf datasheet) */
+ ret = regmap_update_bits(st->map, INV_ICM42600_REG_INT_CONFIG1,
+ INV_ICM42600_INT_CONFIG1_ASYNC_RESET, 0);
+ if (ret)
+ return ret;
+
+ ret = devm_request_threaded_irq(dev, irq,
+ inv_icm42600_trigger_timestamp,
+ inv_icm42600_trigger_int_handler,
+ irq_type, "inv_icm42600", st);
+ if (ret)
+ return ret;
+
+ return devm_iio_trigger_register(dev, st->trigger);
+}
--
2.17.1