iio: imu: st_lsm6dsx: support active-low interrupts

Add support for active low interrupts (IRQF_TRIGGER_LOW and
IRQF_TRIGGER_FALLING). Configure the device as active high or low
according to the requested irq line.

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
index b19a62d8c884d326c834ba06b72037911d084a5c..2a72acc6e0493e48ae6391ae38c29da24fb38d5b 100644 (file)
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
@@ -37,6 +37,8 @@
 #define ST_LSM6DSX_REG_FIFO_THH_ADDR           0x07
 #define ST_LSM6DSX_FIFO_TH_MASK                        GENMASK(11, 0)
 #define ST_LSM6DSX_REG_FIFO_DEC_GXL_ADDR       0x08
+#define ST_LSM6DSX_REG_HLACTIVE_ADDR           0x12
+#define ST_LSM6DSX_REG_HLACTIVE_MASK           BIT(5)
 #define ST_LSM6DSX_REG_FIFO_MODE_ADDR          0x0a
 #define ST_LSM6DSX_FIFO_MODE_MASK              GENMASK(2, 0)
 #define ST_LSM6DSX_FIFO_ODR_MASK               GENMASK(6, 3)
@@ -417,6 +419,7 @@ int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw)
 {
        struct iio_buffer *buffer;
        unsigned long irq_type;
+       bool irq_active_low;
        int i, err;
 
        irq_type = irqd_get_trigger_type(irq_get_irq_data(hw->irq));
@@ -424,12 +427,23 @@ int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw)
        switch (irq_type) {
        case IRQF_TRIGGER_HIGH:
        case IRQF_TRIGGER_RISING:
+               irq_active_low = false;
+               break;
+       case IRQF_TRIGGER_LOW:
+       case IRQF_TRIGGER_FALLING:
+               irq_active_low = true;
                break;
        default:
                dev_info(hw->dev, "mode %lx unsupported\n", irq_type);
                return -EINVAL;
        }
 
+       err = st_lsm6dsx_write_with_mask(hw, ST_LSM6DSX_REG_HLACTIVE_ADDR,
+                                        ST_LSM6DSX_REG_HLACTIVE_MASK,
+                                        irq_active_low);
+       if (err < 0)
+               return err;
+
        err = devm_request_threaded_irq(hw->dev, hw->irq,
                                        st_lsm6dsx_handler_irq,
                                        st_lsm6dsx_handler_thread,