On Sat, 2 Feb 2019 13:55:57 -0800
Martin Kelly <martin@xxxxxxxxxxxxxxxx> wrote:
> From: Martin Kelly <martin@xxxxxxxxxxxxxxxx>
>
> Add interrupt support for the data ready signal on the BMI160, which fires
> an interrupt whenever new accelerometer/gyroscope data is ready to read.
>
> Signed-off-by: Martin Kelly <martin@xxxxxxxxxxxxxxxx>
Applied to the togreg branch of iio.git and pushed out as testing for the
autobuilders to play with it.
Thanks,
Jonathan
> ---
> drivers/iio/imu/bmi160/bmi160.h | 11 ++
> drivers/iio/imu/bmi160/bmi160_core.c | 270 ++++++++++++++++++++++++++++++++++-
> 2 files changed, 278 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/imu/bmi160/bmi160.h b/drivers/iio/imu/bmi160/bmi160.h
> index 2351049d930b..621f5309d735 100644
> --- a/drivers/iio/imu/bmi160/bmi160.h
> +++ b/drivers/iio/imu/bmi160/bmi160.h
> @@ -2,9 +2,20 @@
> #ifndef BMI160_H_
> #define BMI160_H_
>
> +#include <linux/iio/iio.h>
> +
> +struct bmi160_data {
> + struct regmap *regmap;
> + struct iio_trigger *trig;
> +};
> +
> extern const struct regmap_config bmi160_regmap_config;
>
> int bmi160_core_probe(struct device *dev, struct regmap *regmap,
> const char *name, bool use_spi);
>
> +int bmi160_enable_irq(struct regmap *regmap, bool enable);
> +
> +int bmi160_probe_trigger(struct iio_dev *indio_dev, int irq, u32 irq_type);
> +
> #endif /* BMI160_H_ */
> diff --git a/drivers/iio/imu/bmi160/bmi160_core.c b/drivers/iio/imu/bmi160/bmi160_core.c
> index ce61026d84c3..007f7c532ac4 100644
> --- a/drivers/iio/imu/bmi160/bmi160_core.c
> +++ b/drivers/iio/imu/bmi160/bmi160_core.c
> @@ -3,21 +3,25 @@
> * BMI160 - Bosch IMU (accel, gyro plus external magnetometer)
> *
> * Copyright (c) 2016, Intel Corporation.
> + * Copyright (c) 2019, Martin Kelly.
> *
> * IIO core driver for BMI160, with support for I2C/SPI busses
> *
> - * TODO: magnetometer, interrupts, hardware FIFO
> + * TODO: magnetometer, hardware FIFO
> */
> #include <linux/module.h>
> #include <linux/regmap.h>
> #include <linux/acpi.h>
> #include <linux/delay.h>
> +#include <linux/irq.h>
> +#include <linux/of_irq.h>
>
> #include <linux/iio/iio.h>
> #include <linux/iio/triggered_buffer.h>
> #include <linux/iio/trigger_consumer.h>
> #include <linux/iio/buffer.h>
> #include <linux/iio/sysfs.h>
> +#include <linux/iio/trigger.h>
>
> #include "bmi160.h"
>
> @@ -61,8 +65,32 @@
> #define BMI160_CMD_GYRO_PM_FAST_STARTUP 0x17
> #define BMI160_CMD_SOFTRESET 0xB6
>
> +#define BMI160_REG_INT_EN 0x51
> +#define BMI160_DRDY_INT_EN BIT(4)
> +
> +#define BMI160_REG_INT_OUT_CTRL 0x53
> +#define BMI160_INT_OUT_CTRL_MASK 0x0f
> +#define BMI160_INT1_OUT_CTRL_SHIFT 0
> +#define BMI160_INT2_OUT_CTRL_SHIFT 4
> +#define BMI160_EDGE_TRIGGERED BIT(0)
> +#define BMI160_ACTIVE_HIGH BIT(1)
> +#define BMI160_OPEN_DRAIN BIT(2)
> +#define BMI160_OUTPUT_EN BIT(3)
> +
> +#define BMI160_REG_INT_LATCH 0x54
> +#define BMI160_INT1_LATCH_MASK BIT(4)
> +#define BMI160_INT2_LATCH_MASK BIT(5)
> +
> +/* INT1 and INT2 are in the opposite order as in INT_OUT_CTRL! */
> +#define BMI160_REG_INT_MAP 0x56
> +#define BMI160_INT1_MAP_DRDY_EN 0x80
> +#define BMI160_INT2_MAP_DRDY_EN 0x08
> +
> #define BMI160_REG_DUMMY 0x7F
>
> +#define BMI160_NORMAL_WRITE_USLEEP 2
> +#define BMI160_SUSPENDED_WRITE_USLEEP 450
> +
> #define BMI160_ACCEL_PMU_MIN_USLEEP 3800
> #define BMI160_GYRO_PMU_MIN_USLEEP 80000
> #define BMI160_SOFTRESET_USLEEP 1000
> @@ -105,8 +133,9 @@ enum bmi160_sensor_type {
> BMI160_NUM_SENSORS /* must be last */
> };
>
> -struct bmi160_data {
> - struct regmap *regmap;
> +enum bmi160_int_pin {
> + BMI160_PIN_INT1,
> + BMI160_PIN_INT2
> };
>
> const struct regmap_config bmi160_regmap_config = {
> @@ -495,6 +524,186 @@ static const char *bmi160_match_acpi_device(struct device *dev)
> return dev_name(dev);
> }
>
> +static int bmi160_write_conf_reg(struct regmap *regmap, unsigned int reg,
> + unsigned int mask, unsigned int bits,
> + unsigned int write_usleep)
> +{
> + int ret;
> + unsigned int val;
> +
> + ret = regmap_read(regmap, reg, &val);
> + if (ret)
> + return ret;
> +
> + val = (val & ~mask) | bits;
> +
> + ret = regmap_write(regmap, reg, val);
> + if (ret)
> + return ret;
> +
> + /*
> + * We need to wait after writing before we can write again. See the
> + * datasheet, page 93.
> + */
> + usleep_range(write_usleep, write_usleep + 1000);
> +
> + return 0;
> +}
> +
> +static int bmi160_config_pin(struct regmap *regmap, enum bmi160_int_pin pin,
> + bool open_drain, u8 irq_mask,
> + unsigned long write_usleep)
> +{
> + int ret;
> + struct device *dev = regmap_get_device(regmap);
> + u8 int_out_ctrl_shift;
> + u8 int_latch_mask;
> + u8 int_map_mask;
> + u8 int_out_ctrl_mask;
> + u8 int_out_ctrl_bits;
> + const char *pin_name;
> +
> + switch (pin) {
> + case BMI160_PIN_INT1:
> + int_out_ctrl_shift = BMI160_INT1_OUT_CTRL_SHIFT;
> + int_latch_mask = BMI160_INT1_LATCH_MASK;
> + int_map_mask = BMI160_INT1_MAP_DRDY_EN;
> + break;
> + case BMI160_PIN_INT2:
> + int_out_ctrl_shift = BMI160_INT2_OUT_CTRL_SHIFT;
> + int_latch_mask = BMI160_INT2_LATCH_MASK;
> + int_map_mask = BMI160_INT2_MAP_DRDY_EN;
> + break;
> + }
> + int_out_ctrl_mask = BMI160_INT_OUT_CTRL_MASK << int_out_ctrl_shift;
> +
> + /*
> + * Enable the requested pin with the right settings:
> + * - Push-pull/open-drain
> + * - Active low/high
> + * - Edge/level triggered
> + */
> + int_out_ctrl_bits = BMI160_OUTPUT_EN;
> + if (open_drain)
> + /* Default is push-pull. */
> + int_out_ctrl_bits |= BMI160_OPEN_DRAIN;
> + int_out_ctrl_bits |= irq_mask;
> + int_out_ctrl_bits <<= int_out_ctrl_shift;
> +
> + ret = bmi160_write_conf_reg(regmap, BMI160_REG_INT_OUT_CTRL,
> + int_out_ctrl_mask, int_out_ctrl_bits,
> + write_usleep);
> + if (ret)
> + return ret;
> +
> + /* Set the pin to input mode with no latching. */
> + ret = bmi160_write_conf_reg(regmap, BMI160_REG_INT_LATCH,
> + int_latch_mask, int_latch_mask,
> + write_usleep);
> + if (ret)
> + return ret;
> +
> + /* Map interrupts to the requested pin. */
> + ret = bmi160_write_conf_reg(regmap, BMI160_REG_INT_MAP,
> + int_map_mask, int_map_mask,
> + write_usleep);
> + if (ret) {
> + switch (pin) {
> + case BMI160_PIN_INT1:
> + pin_name = "INT1";
> + break;
> + case BMI160_PIN_INT2:
> + pin_name = "INT2";
> + break;
> + }
> + dev_err(dev, "Failed to configure %s IRQ pin", pin_name);
> + }
> +
> + return ret;
> +}
> +
> +int bmi160_enable_irq(struct regmap *regmap, bool enable)
> +{
> + unsigned int enable_bit = 0;
> +
> + if (enable)
> + enable_bit = BMI160_DRDY_INT_EN;
> +
> + return bmi160_write_conf_reg(regmap, BMI160_REG_INT_EN,
> + BMI160_DRDY_INT_EN, enable_bit,
> + BMI160_NORMAL_WRITE_USLEEP);
> +}
> +EXPORT_SYMBOL(bmi160_enable_irq);
> +
> +static int bmi160_get_irq(struct device_node *of_node, enum bmi160_int_pin *pin)
> +{
> + int irq;
> +
> + /* Use INT1 if possible, otherwise fall back to INT2. */
> + irq = of_irq_get_byname(of_node, "INT1");
> + if (irq > 0) {
> + *pin = BMI160_PIN_INT1;
> + return irq;
> + }
> +
> + irq = of_irq_get_byname(of_node, "INT2");
> + if (irq > 0)
> + *pin = BMI160_PIN_INT2;
> +
> + return irq;
> +}
> +
> +static int bmi160_config_device_irq(struct iio_dev *indio_dev, int irq_type,
> + enum bmi160_int_pin pin)
> +{
> + bool open_drain;
> + u8 irq_mask;
> + struct bmi160_data *data = iio_priv(indio_dev);
> + struct device *dev = regmap_get_device(data->regmap);
> +
> + /* Level-triggered, active-low is the default if we set all zeroes. */
> + if (irq_type == IRQF_TRIGGER_RISING)
> + irq_mask = BMI160_ACTIVE_HIGH | BMI160_EDGE_TRIGGERED;
> + else if (irq_type == IRQF_TRIGGER_FALLING)
> + irq_mask = BMI160_EDGE_TRIGGERED;
> + else if (irq_type == IRQF_TRIGGER_HIGH)
> + irq_mask = BMI160_ACTIVE_HIGH;
> + else if (irq_type == IRQF_TRIGGER_LOW)
> + irq_mask = 0;
> + else {
> + dev_err(&indio_dev->dev,
> + "Invalid interrupt type 0x%x specified\n", irq_type);
> + return -EINVAL;
> + }
> +
> + open_drain = of_property_read_bool(dev->of_node, "drive-open-drain");
> +
> + return bmi160_config_pin(data->regmap, pin, open_drain, irq_mask,
> + BMI160_NORMAL_WRITE_USLEEP);
> +}
> +
> +static int bmi160_setup_irq(struct iio_dev *indio_dev, int irq,
> + enum bmi160_int_pin pin)
> +{
> + struct irq_data *desc;
> + u32 irq_type;
> + int ret;
> +
> + desc = irq_get_irq_data(irq);
> + if (!desc) {
> + dev_err(&indio_dev->dev, "Could not find IRQ %d\n", irq);
> + return -EINVAL;
> + }
> +
> + irq_type = irqd_get_trigger_type(desc);
> +
> + ret = bmi160_config_device_irq(indio_dev, irq_type, pin);
> + if (ret)
> + return ret;
> +
> + return bmi160_probe_trigger(indio_dev, irq, irq_type);
> +}
> +
> static int bmi160_chip_init(struct bmi160_data *data, bool use_spi)
> {
> int ret;
> @@ -539,6 +748,49 @@ static int bmi160_chip_init(struct bmi160_data *data, bool use_spi)
> return 0;
> }
>
> +static int bmi160_data_rdy_trigger_set_state(struct iio_trigger *trig,
> + bool enable)
> +{
> + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> + struct bmi160_data *data = iio_priv(indio_dev);
> +
> + return bmi160_enable_irq(data->regmap, enable);
> +}
> +
> +static const struct iio_trigger_ops bmi160_trigger_ops = {
> + .set_trigger_state = &bmi160_data_rdy_trigger_set_state,
> +};
> +
> +int bmi160_probe_trigger(struct iio_dev *indio_dev, int irq, u32 irq_type)
> +{
> + struct bmi160_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + data->trig = devm_iio_trigger_alloc(&indio_dev->dev, "%s-dev%d",
> + indio_dev->name, indio_dev->id);
> +
> + if (data->trig == NULL)
> + return -ENOMEM;
> +
> + ret = devm_request_irq(&indio_dev->dev, irq,
> + &iio_trigger_generic_data_rdy_poll,
> + irq_type, "bmi160", data->trig);
> + if (ret < 0)
> + return ret;
> +
> + data->trig->dev.parent = regmap_get_device(data->regmap);
> + data->trig->ops = &bmi160_trigger_ops;
> + iio_trigger_set_drvdata(data->trig, indio_dev);
> +
> + ret = devm_iio_trigger_register(&indio_dev->dev, data->trig);
> + if (ret)
> + return ret;
> +
> + indio_dev->trig = iio_trigger_get(data->trig);
> +
> + return 0;
> +}
> +
> static void bmi160_chip_uninit(void *data)
> {
> struct bmi160_data *bmi_data = data;
> @@ -552,6 +804,8 @@ int bmi160_core_probe(struct device *dev, struct regmap *regmap,
> {
> struct iio_dev *indio_dev;
> struct bmi160_data *data;
> + int irq;
> + enum bmi160_int_pin int_pin;
> int ret;
>
> indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
> @@ -585,6 +839,16 @@ int bmi160_core_probe(struct device *dev, struct regmap *regmap,
> if (ret < 0)
> return ret;
>
> + irq = bmi160_get_irq(dev->of_node, &int_pin);
> + if (irq > 0) {
> + ret = bmi160_setup_irq(indio_dev, irq, int_pin);
> + if (ret)
> + dev_err(&indio_dev->dev, "Failed to setup IRQ %d\n",
> + irq);
> + } else {
> + dev_info(&indio_dev->dev, "Not setting up IRQ trigger\n");
> + }
> +
> ret = devm_iio_device_register(dev, indio_dev);
> if (ret < 0)
> return ret;
