From 895bf81e6bbfbcd37442aca87ad6ae44be34c54d Mon Sep 17 00:00:00 2001 From: Martin Kelly Date: Sat, 2 Feb 2019 13:55:57 -0800 Subject: [PATCH] iio:bmi160: add drdy interrupt support 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 Signed-off-by: Jonathan Cameron --- 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 + +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 #include #include #include +#include +#include #include #include #include #include #include +#include #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; -- 2.30.2