[RFC 3/8] iio: bmc150: refactor interrupt enabling

[Octavian Purdila <octavian.purdila@intel.com>]

This patch combines the any motion and new data interrupts function
into a single, generic, interrupt enable function. On top of this, we
can later refactor triggers to make it easier to add new triggers.

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
---
 drivers/iio/accel/bmc150-accel.c | 271 +++++++++++++++++----------------------
 1 file changed, 115 insertions(+), 156 deletions(-)

diff --git a/drivers/iio/accel/bmc150-accel.c b/drivers/iio/accel/bmc150-accel.c
index 5bfb09d..ee4afc4 100644
--- a/drivers/iio/accel/bmc150-accel.c
+++ b/drivers/iio/accel/bmc150-accel.c
@@ -144,6 +144,13 @@ struct bmc150_accel_chip_info {
 	const struct bmc150_scale_info scale_table[4];
 };
 
+struct bmc150_accel_interrupt_info {
+	u8 map_reg;
+	u8 map_bitmask;
+	u8 en_reg;
+	u8 en_bitmask;
+};
+
 struct bmc150_accel_data {
 	struct i2c_client *client;
 	struct iio_trigger *dready_trig;
@@ -374,137 +381,6 @@ static int bmc150_accel_chip_init(struct bmc150_accel_data *data)
 	return 0;
 }
 
-static int bmc150_accel_setup_any_motion_interrupt(
-					struct bmc150_accel_data *data,
-					bool status)
-{
-	int ret;
-
-	/* Enable/Disable INT1 mapping */
-	ret = i2c_smbus_read_byte_data(data->client,
-				       BMC150_ACCEL_REG_INT_MAP_0);
-	if (ret < 0) {
-		dev_err(&data->client->dev, "Error reading reg_int_map_0\n");
-		return ret;
-	}
-	if (status)
-		ret |= BMC150_ACCEL_INT_MAP_0_BIT_SLOPE;
-	else
-		ret &= ~BMC150_ACCEL_INT_MAP_0_BIT_SLOPE;
-
-	ret = i2c_smbus_write_byte_data(data->client,
-					BMC150_ACCEL_REG_INT_MAP_0,
-					ret);
-	if (ret < 0) {
-		dev_err(&data->client->dev, "Error writing reg_int_map_0\n");
-		return ret;
-	}
-
-	if (status) {
-		/*
-		 * New data interrupt is always non-latched,
-		 * which will have higher priority, so no need
-		 * to set latched mode, we will be flooded anyway with INTR
-		 */
-		if (!data->dready_trigger_on) {
-			ret = i2c_smbus_write_byte_data(data->client,
-					BMC150_ACCEL_REG_INT_RST_LATCH,
-					BMC150_ACCEL_INT_MODE_LATCH_INT |
-					BMC150_ACCEL_INT_MODE_LATCH_RESET);
-			if (ret < 0) {
-				dev_err(&data->client->dev,
-					"Error writing reg_int_rst_latch\n");
-				return ret;
-			}
-		}
-
-		ret = i2c_smbus_write_byte_data(data->client,
-						BMC150_ACCEL_REG_INT_EN_0,
-						BMC150_ACCEL_INT_EN_BIT_SLP_X |
-						BMC150_ACCEL_INT_EN_BIT_SLP_Y |
-						BMC150_ACCEL_INT_EN_BIT_SLP_Z);
-	} else
-		ret = i2c_smbus_write_byte_data(data->client,
-						BMC150_ACCEL_REG_INT_EN_0,
-						0);
-
-	if (ret < 0) {
-		dev_err(&data->client->dev, "Error writing reg_int_en_0\n");
-		return ret;
-	}
-
-	return 0;
-}
-
-static int bmc150_accel_setup_new_data_interrupt(struct bmc150_accel_data *data,
-					   bool status)
-{
-	int ret;
-
-	/* Enable/Disable INT1 mapping */
-	ret = i2c_smbus_read_byte_data(data->client,
-				       BMC150_ACCEL_REG_INT_MAP_1);
-	if (ret < 0) {
-		dev_err(&data->client->dev, "Error reading reg_int_map_1\n");
-		return ret;
-	}
-	if (status)
-		ret |= BMC150_ACCEL_INT_MAP_1_BIT_DATA;
-	else
-		ret &= ~BMC150_ACCEL_INT_MAP_1_BIT_DATA;
-
-	ret = i2c_smbus_write_byte_data(data->client,
-					BMC150_ACCEL_REG_INT_MAP_1,
-					ret);
-	if (ret < 0) {
-		dev_err(&data->client->dev, "Error writing reg_int_map_1\n");
-		return ret;
-	}
-
-	if (status) {
-		/*
-		 * Set non latched mode interrupt and clear any latched
-		 * interrupt
-		 */
-		ret = i2c_smbus_write_byte_data(data->client,
-					BMC150_ACCEL_REG_INT_RST_LATCH,
-					BMC150_ACCEL_INT_MODE_NON_LATCH_INT |
-					BMC150_ACCEL_INT_MODE_LATCH_RESET);
-		if (ret < 0) {
-			dev_err(&data->client->dev,
-				"Error writing reg_int_rst_latch\n");
-			return ret;
-		}
-
-		ret = i2c_smbus_write_byte_data(data->client,
-					BMC150_ACCEL_REG_INT_EN_1,
-					BMC150_ACCEL_INT_EN_BIT_DATA_EN);
-
-	} else {
-		/* Restore default interrupt mode */
-		ret = i2c_smbus_write_byte_data(data->client,
-					BMC150_ACCEL_REG_INT_RST_LATCH,
-					BMC150_ACCEL_INT_MODE_LATCH_INT |
-					BMC150_ACCEL_INT_MODE_LATCH_RESET);
-		if (ret < 0) {
-			dev_err(&data->client->dev,
-				"Error writing reg_int_rst_latch\n");
-			return ret;
-		}
-
-		ret = i2c_smbus_write_byte_data(data->client,
-						BMC150_ACCEL_REG_INT_EN_1,
-						0);
-	}
-
-	if (ret < 0) {
-		dev_err(&data->client->dev, "Error writing reg_int_en_1\n");
-		return ret;
-	}
-
-	return 0;
-}
-
 static int bmc150_accel_get_bw(struct bmc150_accel_data *data, int *val,
 			       int *val2)
 {
@@ -559,6 +435,99 @@ static int bmc150_accel_set_power_state(struct bmc150_accel_data *data, bool on)
 }
 #endif
 
+static struct bmc150_accel_interrupt_info bmc150_accel_interrupts[] = {
+	{ /* data ready interrupt */
+		.map_reg = BMC150_ACCEL_REG_INT_MAP_1,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_DATA,
+		.en_reg = BMC150_ACCEL_REG_INT_EN_1,
+		.en_bitmask = BMC150_ACCEL_INT_EN_BIT_DATA_EN,
+	},
+	{  /* motion interrupt */
+		.map_reg = BMC150_ACCEL_REG_INT_MAP_0,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_0_BIT_SLOPE,
+		.en_reg = BMC150_ACCEL_REG_INT_EN_0,
+		.en_bitmask =  BMC150_ACCEL_INT_EN_BIT_SLP_X |
+			BMC150_ACCEL_INT_EN_BIT_SLP_Y |
+			BMC150_ACCEL_INT_EN_BIT_SLP_Z
+	},
+};
+
+static int bmc150_accel_set_interrupt(struct bmc150_accel_data *data,
+				      struct bmc150_accel_interrupt_info *info,
+				      bool state)
+{
+	int ret;
+
+	/*
+	 * We will expect the enable and disable to do operation in
+	 * in reverse order. This will happen here anyway as our
+	 * resume operation uses sync mode runtime pm calls, the
+	 * suspend operation will be delayed by autosuspend delay
+	 * So the disable operation will still happen in reverse of
+	 * enable operation. When runtime pm is disabled the mode
+	 * is always on so sequence doesn't matter
+	 */
+	ret = bmc150_accel_set_power_state(data, state);
+	if (ret < 0)
+		return ret;
+
+
+	/* map the interrupt to the appropriate pins */
+	if (info->map_reg) {
+		ret = i2c_smbus_read_byte_data(data->client, info->map_reg);
+		if (ret < 0) {
+			dev_err(&data->client->dev, "Error reading reg_int_map\n");
+			return ret;
+		}
+		if (state)
+			ret |= info->map_bitmask;
+		else
+			ret &= ~info->map_bitmask;
+
+		ret = i2c_smbus_write_byte_data(data->client, info->map_reg,
+						ret);
+		if (ret < 0) {
+			dev_err(&data->client->dev, "Error writing reg_int_map\n");
+			return ret;
+		}
+	}
+
+	/* enable/disable the interrupt */
+	ret = i2c_smbus_read_byte_data(data->client, info->en_reg);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_int_en\n");
+		return ret;
+	}
+
+	if (state)
+		ret |= info->en_bitmask;
+	else
+		ret &= ~info->en_bitmask;
+
+	ret = i2c_smbus_write_byte_data(data->client, info->en_reg, ret);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_int_en\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmc150_accel_setup_any_motion_interrupt(
+					struct bmc150_accel_data *data,
+					bool status)
+{
+	return bmc150_accel_set_interrupt(data, &bmc150_accel_interrupts[1],
+					  status);
+}
+
+static int bmc150_accel_setup_new_data_interrupt(struct bmc150_accel_data *data,
+					   bool status)
+{
+	return bmc150_accel_set_interrupt(data, &bmc150_accel_interrupts[0],
+					  status);
+}
+
 static int bmc150_accel_set_scale(struct bmc150_accel_data *data, int val)
 {
 	int ret, i;
@@ -808,22 +777,6 @@ static int bmc150_accel_write_event_config(struct iio_dev *indio_dev,
 		return 0;
 	}
 
-	/*
-	 * We will expect the enable and disable to do operation in
-	 * in reverse order. This will happen here anyway as our
-	 * resume operation uses sync mode runtime pm calls, the
-	 * suspend operation will be delayed by autosuspend delay
-	 * So the disable operation will still happen in reverse of
-	 * enable operation. When runtime pm is disabled the mode
-	 * is always on so sequence doesn't matter
-	 */
-
-	ret = bmc150_accel_set_power_state(data, state);
-	if (ret < 0) {
-		mutex_unlock(&data->mutex);
-		return ret;
-	}
-
 	ret =  bmc150_accel_setup_any_motion_interrupt(data, state);
 	if (ret < 0) {
 		mutex_unlock(&data->mutex);
@@ -1055,15 +1008,6 @@ static int bmc150_accel_data_rdy_trigger_set_state(struct iio_trigger *trig,
 		return 0;
 	}
 
-	/*
-	 * Refer to comment in bmc150_accel_write_event_config for
-	 * enable/disable operation order
-	 */
-	ret = bmc150_accel_set_power_state(data, state);
-	if (ret < 0) {
-		mutex_unlock(&data->mutex);
-		return ret;
-	}
 	if (data->motion_trig == trig)
 		ret =  bmc150_accel_setup_any_motion_interrupt(data, state);
 	else
@@ -1240,6 +1184,21 @@ static int bmc150_accel_probe(struct i2c_client *client,
 		if (ret)
 			return ret;
 
+		/*
+		 * Set latched mode interrupt. While certain interrupts are
+		 * non-latched regardless of this settings (e.g. new data) we
+		 * want to use latch mode when we can to prevent interrupt
+		 * flooding.
+		 */
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMC150_ACCEL_REG_INT_RST_LATCH,
+					     BMC150_ACCEL_INT_MODE_LATCH_RESET);
+		if (ret < 0) {
+			dev_err(&data->client->dev, "Error writing reg_int_rst_latch\n");
+			return ret;
+		}
+
+
 		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
 							   "%s-dev%d",
 							   indio_dev->name,
-- 
1.9.1