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

From: Jonathan Cameron
Date: Sun May 31 2020 - 08:16:22 EST

On Wed, 27 May 2020 20:57:07 +0200
Jean-Baptiste Maneyrol <jmaneyrol@xxxxxxxxxxxxxx> wrote:

> 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>

Some nitpicks inline - all cases where a blank line would slightly
help readability.

J

> ---
> 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;
> + }

blank line here

> + switch (irq_type) {
> + case IRQF_TRIGGER_LOW:
> + case IRQF_TRIGGER_HIGH:
> + val |= INV_ICM42600_INT_CONFIG_INT1_LATCHED;
> + break;
> + default:
> + break;
> + }

blank line here.

> + if (!open_drain)
> + val |= INV_ICM42600_INT_CONFIG_INT1_PUSH_PULL;

blank line here

> + 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;
> + }

nitpick: Blank line here

> + irq_type = irqd_get_trigger_type(irq_desc);
> + if (!irq_type)
> + irq_type = IRQF_TRIGGER_FALLING;

blank line here.

> + 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[] = {