iio: st_sensors: add register mask for status register

Introduce register mask for data-ready status register since
pressure sensors (e.g. LPS22HB) export just two channels
(BIT(0) and BIT(1)) and BIT(2) is marked reserved while in
st_sensors_new_samples_available() value read from status register
is masked using 0x7.
Moreover do not mask status register using active_scan_mask since
now status value is properly masked and if the result is not zero the
interrupt has to be consumed by the driver. This fix an issue on LPS25H
and LPS331AP where channel definition is swapped respect to status
register.
Furthermore that change allows to properly support new devices
(e.g LIS2DW12) that report just ZYXDA (data-ready) field in status register
to figure out if the interrupt has been generated by the device.

Fixes: 97865fe41322 (iio: st_sensors: verify interrupt event to status)
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/accel/st_accel_core.c

@@ -164,7 +164,10 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 			.mask_int2 = 0x00,
 			.addr_ihl = 0x25,
 			.mask_ihl = 0x02,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.sim = {
 			.addr = 0x23,
@@ -236,7 +239,10 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 			.mask_ihl = 0x80,
 			.addr_od = 0x22,
 			.mask_od = 0x40,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.sim = {
 			.addr = 0x23,
@@ -318,7 +324,10 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 			.mask_int2 = 0x00,
 			.addr_ihl = 0x23,
 			.mask_ihl = 0x40,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 			.ig1 = {
 				.en_addr = 0x23,
 				.en_mask = 0x08,
@@ -389,7 +398,10 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 		.drdy_irq = {
 			.addr = 0x21,
 			.mask_int1 = 0x04,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.sim = {
 			.addr = 0x21,
@@ -451,7 +463,10 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 			.mask_ihl = 0x80,
 			.addr_od = 0x22,
 			.mask_od = 0x40,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.sim = {
 			.addr = 0x21,
@@ -569,7 +584,10 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 		.drdy_irq = {
 			.addr = 0x21,
 			.mask_int1 = 0x04,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.sim = {
 			.addr = 0x21,
@@ -640,7 +658,10 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 			.mask_int2 = 0x00,
 			.addr_ihl = 0x25,
 			.mask_ihl = 0x02,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.sim = {
 			.addr = 0x23,

drivers/iio/common/st_sensors/st_sensors_core.c

@@ -470,7 +470,7 @@ int st_sensors_set_dataready_irq(struct iio_dev *indio_dev, bool enable)
 		 * different one. Take into account irq status register
 		 * to understand if irq trigger can be properly supported
 		 */
-		if (sdata->sensor_settings->drdy_irq.addr_stat_drdy)
+		if (sdata->sensor_settings->drdy_irq.stat_drdy.addr)
 			sdata->hw_irq_trigger = enable;
 		return 0;
 	}

drivers/iio/common/st_sensors/st_sensors_trigger.c

@@ -31,7 +31,7 @@ static int st_sensors_new_samples_available(struct iio_dev *indio_dev,
 	int ret;
 
 	/* How would I know if I can't check it? */
-	if (!sdata->sensor_settings->drdy_irq.addr_stat_drdy)
+	if (!sdata->sensor_settings->drdy_irq.stat_drdy.addr)
 		return -EINVAL;
 
 	/* No scan mask, no interrupt */
@@ -39,23 +39,15 @@ static int st_sensors_new_samples_available(struct iio_dev *indio_dev,
 		return 0;
 
 	ret = sdata->tf->read_byte(&sdata->tb, sdata->dev,
-			sdata->sensor_settings->drdy_irq.addr_stat_drdy,
+			sdata->sensor_settings->drdy_irq.stat_drdy.addr,
 			&status);
 	if (ret < 0) {
 		dev_err(sdata->dev,
 			"error checking samples available\n");
 		return ret;
 	}
-	/*
-	 * the lower bits of .active_scan_mask[0] is directly mapped
-	 * to the channels on the sensor: either bit 0 for
-	 * one-dimensional sensors, or e.g. x,y,z for accelerometers,
-	 * gyroscopes or magnetometers. No sensor use more than 3
-	 * channels, so cut the other status bits here.
-	 */
-	status &= 0x07;
 
-	if (status & (u8)indio_dev->active_scan_mask[0])
+	if (status & sdata->sensor_settings->drdy_irq.stat_drdy.mask)
 		return 1;
 
 	return 0;
@@ -212,7 +204,7 @@ int st_sensors_allocate_trigger(struct iio_dev *indio_dev,
 	 * it was "our" interrupt.
 	 */
 	if (sdata->int_pin_open_drain &&
-	    sdata->sensor_settings->drdy_irq.addr_stat_drdy)
+	    sdata->sensor_settings->drdy_irq.stat_drdy.addr)
 		irq_trig |= IRQF_SHARED;
 
 	err = request_threaded_irq(sdata->get_irq_data_ready(indio_dev),

drivers/iio/gyro/st_gyro_core.c

@@ -118,7 +118,10 @@ static const struct st_sensor_settings st_gyro_sensors_settings[] = {
 			 * drain settings, but only for INT1 and not
 			 * for the DRDY line on INT2.
 			 */
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.multi_read_bit = true,
 		.bootime = 2,
@@ -188,7 +191,10 @@ static const struct st_sensor_settings st_gyro_sensors_settings[] = {
 			 * drain settings, but only for INT1 and not
 			 * for the DRDY line on INT2.
 			 */
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.multi_read_bit = true,
 		.bootime = 2,
@@ -253,7 +259,10 @@ static const struct st_sensor_settings st_gyro_sensors_settings[] = {
 			 * drain settings, but only for INT1 and not
 			 * for the DRDY line on INT2.
 			 */
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.multi_read_bit = true,
 		.bootime = 2,

drivers/iio/magnetometer/st_magn_core.c

@@ -317,7 +317,10 @@ static const struct st_sensor_settings st_magn_sensors_settings[] = {
 		},
 		.drdy_irq = {
 			/* drdy line is routed drdy pin */
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x07,
+			},
 		},
 		.multi_read_bit = true,
 		.bootime = 2,
@@ -361,7 +364,10 @@ static const struct st_sensor_settings st_magn_sensors_settings[] = {
 		.drdy_irq = {
 			.addr = 0x62,
 			.mask_int1 = 0x01,
-			.addr_stat_drdy = 0x67,
+			.stat_drdy = {
+				.addr = 0x67,
+				.mask = 0x07,
+			},
 		},
 		.multi_read_bit = false,
 		.bootime = 2,

drivers/iio/pressure/st_pressure_core.c

@@ -287,7 +287,10 @@ static const struct st_sensor_settings st_press_sensors_settings[] = {
 			.mask_ihl = 0x80,
 			.addr_od = 0x22,
 			.mask_od = 0x40,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x03,
+			},
 		},
 		.multi_read_bit = true,
 		.bootime = 2,
@@ -395,7 +398,10 @@ static const struct st_sensor_settings st_press_sensors_settings[] = {
 			.mask_ihl = 0x80,
 			.addr_od = 0x22,
 			.mask_od = 0x40,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x03,
+			},
 		},
 		.multi_read_bit = true,
 		.bootime = 2,
@@ -456,7 +462,10 @@ static const struct st_sensor_settings st_press_sensors_settings[] = {
 			.mask_ihl = 0x80,
 			.addr_od = 0x12,
 			.mask_od = 0x40,
-			.addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR,
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = 0x03,
+			},
 		},
 		.multi_read_bit = false,
 		.bootime = 2,

include/linux/iio/common/st_sensors.h

@@ -139,7 +139,7 @@ struct st_sensor_das {
  * @mask_ihl: mask to enable/disable active low on the INT lines.
  * @addr_od: address to enable/disable Open Drain on the INT lines.
  * @mask_od: mask to enable/disable Open Drain on the INT lines.
- * @addr_stat_drdy: address to read status of DRDY (data ready) interrupt
+ * struct stat_drdy - status register of DRDY (data ready) interrupt.
  * struct ig1 - represents the Interrupt Generator 1 of sensors.
  * @en_addr: address of the enable ig1 register.
  * @en_mask: mask to write the on/off value for enable.
@@ -152,7 +152,10 @@ struct st_sensor_data_ready_irq {
 	u8 mask_ihl;
 	u8 addr_od;
 	u8 mask_od;
-	u8 addr_stat_drdy;
+	struct {
+		u8 addr;
+		u8 mask;
+	} stat_drdy;
 	struct {
 		u8 en_addr;
 		u8 en_mask;