[PATCH v2 08/12] iio: imu: inv_icm42600: add device interrupt

From: Jean-Baptiste Maneyrol
Date: Wed May 27 2020 - 14:58:16 EST


Add INT1 interrupt support. Support interrupt edge and level,
active high or low. Push-pull or open-drain configurations.

Interrupt will be used to read data from the FIFO.

Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@xxxxxxxxxxxxxx>
---
drivers/iio/imu/inv_icm42600/inv_icm42600.h | 2 +-
.../iio/imu/inv_icm42600/inv_icm42600_core.c | 96 ++++++++++++++++++-
.../iio/imu/inv_icm42600/inv_icm42600_i2c.c | 3 +-
.../iio/imu/inv_icm42600/inv_icm42600_spi.c | 3 +-
4 files changed, 100 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600.h b/drivers/iio/imu/inv_icm42600/inv_icm42600.h
index c534acae0308..43749f56426c 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600.h
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600.h
@@ -372,7 +372,7 @@ 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);
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
index e7f7835aca9b..246c1eb52231 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
@@ -9,8 +9,11 @@
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/mutex.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/regulator/consumer.h>
#include <linux/pm_runtime.h>
+#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/iio/iio.h>

@@ -409,6 +412,79 @@ static int inv_icm42600_setup(struct inv_icm42600_state *st,
return inv_icm42600_set_conf(st, hw->conf);
}

+static irqreturn_t inv_icm42600_irq_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;
+
+ /* FIFO full */
+ if (status & INV_ICM42600_INT_STATUS_FIFO_FULL)
+ dev_warn(dev, "FIFO full data lost!\n");
+
+out_unlock:
+ mutex_unlock(&st->lock);
+ return IRQ_HANDLED;
+}
+
+/**
+ * inv_icm42600_irq_init() - initialize int pin and interrupt handler
+ * @st: driver internal state
+ * @irq: irq number
+ * @irq_type: irq trigger type
+ * @open_drain: true if irq is open drain, false for push-pull
+ *
+ * Returns 0 on success, a negative error code otherwise.
+ */
+static int inv_icm42600_irq_init(struct inv_icm42600_state *st, int irq,
+ int irq_type, bool open_drain)
+{
+ struct device *dev = regmap_get_device(st->map);
+ unsigned int val;
+ int ret;
+
+ /* configure INT1 interrupt: default is active low on edge */
+ switch (irq_type) {
+ case IRQF_TRIGGER_RISING:
+ case IRQF_TRIGGER_HIGH:
+ val = INV_ICM42600_INT_CONFIG_INT1_ACTIVE_HIGH;
+ break;
+ default:
+ val = INV_ICM42600_INT_CONFIG_INT1_ACTIVE_LOW;
+ break;
+ }
+ switch (irq_type) {
+ case IRQF_TRIGGER_LOW:
+ case IRQF_TRIGGER_HIGH:
+ val |= INV_ICM42600_INT_CONFIG_INT1_LATCHED;
+ break;
+ default:
+ break;
+ }
+ if (!open_drain)
+ 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;
+
+ return devm_request_threaded_irq(dev, irq, NULL,
+ inv_icm42600_irq_handler, irq_type,
+ "inv_icm42600", st);
+}
+
static int inv_icm42600_enable_regulator_vddio(struct inv_icm42600_state *st)
{
int ret;
@@ -453,11 +529,14 @@ 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;
+ bool open_drain;
int ret;

if (chip < 0 || chip >= INV_CHIP_NB) {
@@ -465,6 +544,17 @@ int inv_icm42600_core_probe(struct regmap *regmap, int chip,
return -ENODEV;
}

+ /* get irq properties, 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;
+ open_drain = device_property_read_bool(dev, "drive-open-drain");
+
st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
if (!st)
return -ENOMEM;
@@ -518,6 +608,10 @@ int inv_icm42600_core_probe(struct regmap *regmap, int chip,
if (ret)
return ret;

+ ret = inv_icm42600_irq_init(st, irq, irq_type, open_drain);
+ if (ret)
+ return ret;
+
/* setup runtime power management */
ret = pm_runtime_set_active(dev);
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 4789cead23b3..85b1934cec60 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
@@ -64,7 +64,8 @@ static int inv_icm42600_probe(struct i2c_client *client)
if (IS_ERR(regmap))
return PTR_ERR(regmap);

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

static const struct of_device_id inv_icm42600_of_matches[] = {
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c
index a9c5e2fdbe2a..323789697a08 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_spi.c
@@ -63,7 +63,8 @@ static int inv_icm42600_probe(struct spi_device *spi)
if (IS_ERR(regmap))
return PTR_ERR(regmap);

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

static const struct of_device_id inv_icm42600_of_matches[] = {
--
2.17.1