iio: accel: bmc150: Make it possible to configure INT2 instead of INT1

Some Bosch accelerometers have two interrupt pins (INT1 and INT2).
At the moment, the driver uses only the first one, which is fine for
most situations. However, some boards might only have INT2 connected
for some reason.

Add the necessary bits and configuration to set up INT2. Then try
to detect this situation at least for device tree setups by checking
if the first interrupt (the one picked by the I2C/SPI core) is actually
named "INT2" using the interrupt-names property.

of_irq_get_byname() returns either 0 or some error code in case
the driver probed without device tree, so in all other cases we fall
back to configuring INT1 as before.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210802155657.102766-4-stephan@gerhold.net
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

1 files changed, 59 insertions, 12 deletions

diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c
index 5ce384ebe6c7..8d3dd3c2bcc2 100644
--- a/drivers/iio/accel/bmc150-accel-core.c
+++ b/drivers/iio/accel/bmc150-accel-core.c
@@ -10,6 +10,7 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
+#include <linux/of_irq.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
 #include <linux/iio/iio.h>
@@ -57,12 +58,18 @@
 #define BMC150_ACCEL_RESET_VAL			0xB6
 
 #define BMC150_ACCEL_REG_INT_MAP_0		0x19
-#define BMC150_ACCEL_INT_MAP_0_BIT_SLOPE	BIT(2)
+#define BMC150_ACCEL_INT_MAP_0_BIT_INT1_SLOPE	BIT(2)
 
 #define BMC150_ACCEL_REG_INT_MAP_1		0x1A
-#define BMC150_ACCEL_INT_MAP_1_BIT_DATA		BIT(0)
-#define BMC150_ACCEL_INT_MAP_1_BIT_FWM		BIT(1)
-#define BMC150_ACCEL_INT_MAP_1_BIT_FFULL	BIT(2)
+#define BMC150_ACCEL_INT_MAP_1_BIT_INT1_DATA	BIT(0)
+#define BMC150_ACCEL_INT_MAP_1_BIT_INT1_FWM	BIT(1)
+#define BMC150_ACCEL_INT_MAP_1_BIT_INT1_FFULL	BIT(2)
+#define BMC150_ACCEL_INT_MAP_1_BIT_INT2_FFULL	BIT(5)
+#define BMC150_ACCEL_INT_MAP_1_BIT_INT2_FWM	BIT(6)
+#define BMC150_ACCEL_INT_MAP_1_BIT_INT2_DATA	BIT(7)
+
+#define BMC150_ACCEL_REG_INT_MAP_2		0x1B
+#define BMC150_ACCEL_INT_MAP_2_BIT_INT2_SLOPE	BIT(2)
 
 #define BMC150_ACCEL_REG_INT_RST_LATCH		0x21
 #define BMC150_ACCEL_INT_MODE_LATCH_RESET	0x80
@@ -81,6 +88,7 @@
 
 #define BMC150_ACCEL_REG_INT_OUT_CTRL		0x20
 #define BMC150_ACCEL_INT_OUT_CTRL_INT1_LVL	BIT(0)
+#define BMC150_ACCEL_INT_OUT_CTRL_INT2_LVL	BIT(2)
 
 #define BMC150_ACCEL_REG_INT_5			0x27
 #define BMC150_ACCEL_SLOPE_DUR_MASK		0x03
@@ -476,21 +484,24 @@ static bool bmc150_apply_acpi_orientation(struct device *dev,
 }
 #endif
 
-static const struct bmc150_accel_interrupt_info {
+struct bmc150_accel_interrupt_info {
 	u8 map_reg;
 	u8 map_bitmask;
 	u8 en_reg;
 	u8 en_bitmask;
-} bmc150_accel_interrupts[BMC150_ACCEL_INTERRUPTS] = {
+};
+
+static const struct bmc150_accel_interrupt_info
+bmc150_accel_interrupts_int1[BMC150_ACCEL_INTERRUPTS] = {
 	{ /* data ready interrupt */
 		.map_reg = BMC150_ACCEL_REG_INT_MAP_1,
-		.map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_DATA,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_INT1_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,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_0_BIT_INT1_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 |
@@ -498,19 +509,55 @@ static const struct bmc150_accel_interrupt_info {
 	},
 	{ /* fifo watermark interrupt */
 		.map_reg = BMC150_ACCEL_REG_INT_MAP_1,
-		.map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_FWM,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_INT1_FWM,
+		.en_reg = BMC150_ACCEL_REG_INT_EN_1,
+		.en_bitmask = BMC150_ACCEL_INT_EN_BIT_FWM_EN,
+	},
+};
+
+static const struct bmc150_accel_interrupt_info
+bmc150_accel_interrupts_int2[BMC150_ACCEL_INTERRUPTS] = {
+	{ /* data ready interrupt */
+		.map_reg = BMC150_ACCEL_REG_INT_MAP_1,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_INT2_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_2,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_2_BIT_INT2_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
+	},
+	{ /* fifo watermark interrupt */
+		.map_reg = BMC150_ACCEL_REG_INT_MAP_1,
+		.map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_INT2_FWM,
 		.en_reg = BMC150_ACCEL_REG_INT_EN_1,
 		.en_bitmask = BMC150_ACCEL_INT_EN_BIT_FWM_EN,
 	},
 };
 
 static void bmc150_accel_interrupts_setup(struct iio_dev *indio_dev,
-					  struct bmc150_accel_data *data)
+					  struct bmc150_accel_data *data, int irq)
 {
+	const struct bmc150_accel_interrupt_info *irq_info = NULL;
+	struct device *dev = regmap_get_device(data->regmap);
 	int i;
 
+	/*
+	 * For now we map all interrupts to the same output pin.
+	 * However, some boards may have just INT2 (and not INT1) connected,
+	 * so we try to detect which IRQ it is based on the interrupt-names.
+	 * Without interrupt-names, we assume the irq belongs to INT1.
+	 */
+	irq_info = bmc150_accel_interrupts_int1;
+	if (irq == of_irq_get_byname(dev->of_node, "INT2"))
+		irq_info = bmc150_accel_interrupts_int2;
+
 	for (i = 0; i < BMC150_ACCEL_INTERRUPTS; i++)
-		data->interrupts[i].info = &bmc150_accel_interrupts[i];
+		data->interrupts[i].info = &irq_info[i];
 }
 
 static int bmc150_accel_set_interrupt(struct bmc150_accel_data *data, int i,
@@ -1714,7 +1761,7 @@ int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq,
 			goto err_buffer_cleanup;
 		}
 
-		bmc150_accel_interrupts_setup(indio_dev, data);
+		bmc150_accel_interrupts_setup(indio_dev, data, irq);
 
 		ret = bmc150_accel_triggers_setup(indio_dev, data);
 		if (ret)