iio: accel: bma180: BMA254 support

This adds support for the BMA254 variant of this
accelerometer. The only difference for the simple IIO
driver is that values are 12 bit and the temperature
offset differs by 1 degree.

Whilst wildcards in naming are normally frowned upon:

The cases where I have labeled variables "25x" is where the
models are identical, so as to make things easier for people
that want to add support for BMA253 and BMA255.

Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/accel/bma180.txt

-* Bosch BMA180 / BMA250 triaxial acceleration sensor
+* Bosch BMA180 / BMA25x triaxial acceleration sensor
 
 http://omapworld.com/BMA180_111_1002839.pdf
 http://ae-bst.resource.bosch.com/media/products/dokumente/bma250/bst-bma250-ds002-05.pdf
 
 Required properties:
 
-  - compatible : should be "bosch,bma180" or "bosch,bma250"
+  - compatible : should be one of:
+    "bosch,bma180"
+    "bosch,bma250"
+    "bosch,bma254"
   - reg : the I2C address of the sensor
 
 Optional properties:

drivers/iio/accel/Kconfig

@@ -89,13 +89,13 @@ config ADXL372_I2C
 	  module will be called adxl372_i2c.
 
 config BMA180
-	tristate "Bosch BMA180/BMA250 3-Axis Accelerometer Driver"
+	tristate "Bosch BMA180/BMA25x 3-Axis Accelerometer Driver"
 	depends on I2C
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
 	help
 	  Say Y here if you want to build a driver for the Bosch BMA180 or
-	  BMA250 triaxial acceleration sensor.
+	  BMA25x triaxial acceleration sensor.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called bma180.

drivers/iio/accel/bma180.c

@@ -9,6 +9,7 @@
  * SPI is not supported by driver
  * BMA180: 7-bit I2C slave address 0x40 or 0x41
  * BMA250: 7-bit I2C slave address 0x18 or 0x19
+ * BMA254: 7-bit I2C slave address 0x18 or 0x19
  */
 
 #include <linux/module.h>
@@ -34,17 +35,20 @@
 enum chip_ids {
 	BMA180,
 	BMA250,
+	BMA254,
 };
 
 struct bma180_data;
 
 struct bma180_part_info {
+	u8 chip_id;
 	const struct iio_chan_spec *channels;
 	unsigned int num_channels;
 	const int *scale_table;
 	unsigned int num_scales;
 	const int *bw_table;
 	unsigned int num_bw;
+	int center_temp;
 
 	u8 int_reset_reg, int_reset_mask;
 	u8 sleep_reg, sleep_mask;
@@ -52,6 +56,7 @@ struct bma180_part_info {
 	u8 scale_reg, scale_mask;
 	u8 power_reg, power_mask, lowpower_val;
 	u8 int_enable_reg, int_enable_mask;
+	u8 int_map_reg, int_enable_dataready_int1_mask;
 	u8 softreset_reg;
 
 	int (*chip_config)(struct bma180_data *data);
@@ -90,6 +95,8 @@ struct bma180_part_info {
 #define BMA180_RESET_VAL	0xb6
 
 #define BMA180_ID_REG_VAL	0x03
+#define BMA250_ID_REG_VAL	0x03
+#define BMA254_ID_REG_VAL	0xfa /* 250 decimal */
 
 /* Chip power modes */
 #define BMA180_LOW_POWER	0x03
@@ -110,6 +117,23 @@ struct bma180_part_info {
 #define BMA250_INT1_DATA_MASK	BIT(0)
 #define BMA250_INT_RESET_MASK	BIT(7) /* Reset pending interrupts */
 
+#define BMA254_RANGE_REG	0x0f
+#define BMA254_BW_REG		0x10
+#define BMA254_POWER_REG	0x11
+#define BMA254_RESET_REG	0x14
+#define BMA254_INT_ENABLE_REG	0x17
+#define BMA254_INT_MAP_REG	0x1a
+#define BMA254_INT_RESET_REG	0x21
+
+#define BMA254_RANGE_MASK	GENMASK(3, 0) /* Range of accel values */
+#define BMA254_BW_MASK		GENMASK(4, 0) /* Accel bandwidth */
+#define BMA254_SUSPEND_MASK	BIT(7) /* chip will sleep */
+#define BMA254_LOWPOWER_MASK	BIT(6)
+#define BMA254_DATA_INTEN_MASK	BIT(4)
+#define BMA254_INT2_DATA_MASK	BIT(7)
+#define BMA254_INT1_DATA_MASK	BIT(0)
+#define BMA254_INT_RESET_MASK	BIT(7) /* Reset pending interrupts */
+
 struct bma180_data {
 	struct regulator *vdd_supply;
 	struct regulator *vddio_supply;
@@ -135,8 +159,8 @@ enum bma180_chan {
 static int bma180_bw_table[] = { 10, 20, 40, 75, 150, 300 }; /* Hz */
 static int bma180_scale_table[] = { 1275, 1863, 2452, 3727, 4903, 9709, 19417 };
 
-static int bma250_bw_table[] = { 8, 16, 31, 63, 125, 250 }; /* Hz */
-static int bma250_scale_table[] = { 0, 0, 0, 38344, 0, 76590, 0, 0, 153180, 0,
+static int bma25x_bw_table[] = { 8, 16, 31, 63, 125, 250 }; /* Hz */
+static int bma25x_scale_table[] = { 0, 0, 0, 38344, 0, 76590, 0, 0, 153180, 0,
 	0, 0, 306458 };
 
 static int bma180_get_data_reg(struct bma180_data *data, enum bma180_chan chan)
@@ -310,8 +334,11 @@ static int bma180_chip_init(struct bma180_data *data)
 
 	if (ret < 0)
 		return ret;
-	if (ret != BMA180_ID_REG_VAL)
+	if (ret != data->part_info->chip_id) {
+		dev_err(&data->client->dev, "wrong chip ID %d expected %d\n",
+			ret, data->part_info->chip_id);
 		return -ENODEV;
+	}
 
 	ret = bma180_soft_reset(data);
 	if (ret)
@@ -358,7 +385,7 @@ static int bma180_chip_config(struct bma180_data *data)
 	return ret;
 }
 
-static int bma250_chip_config(struct bma180_data *data)
+static int bma25x_chip_config(struct bma180_data *data)
 {
 	int ret = bma180_chip_init(data);
 
@@ -370,8 +397,12 @@ static int bma250_chip_config(struct bma180_data *data)
 	ret = bma180_set_scale(data, 38344); /* 2 G */
 	if (ret)
 		goto err;
-	ret = bma180_set_bits(data, BMA250_INT_MAP_REG,
-		BMA250_INT1_DATA_MASK, 1);
+	/*
+	 * This enables dataready interrupt on the INT1 pin
+	 * FIXME: support using the INT2 pin
+	 */
+	ret = bma180_set_bits(data, data->part_info->int_map_reg,
+		data->part_info->int_enable_dataready_int1_mask, 1);
 	if (ret)
 		goto err;
 
@@ -397,7 +428,7 @@ static void bma180_chip_disable(struct bma180_data *data)
 	dev_err(&data->client->dev, "failed to disable the chip\n");
 }
 
-static void bma250_chip_disable(struct bma180_data *data)
+static void bma25x_chip_disable(struct bma180_data *data)
 {
 	if (bma180_set_new_data_intr_state(data, false))
 		goto err;
@@ -500,7 +531,7 @@ static int bma180_read_raw(struct iio_dev *indio_dev,
 			return -EINVAL;
 		}
 	case IIO_CHAN_INFO_OFFSET:
-		*val = 48; /* 0 LSB @ 24 degree C */
+		*val = data->part_info->center_temp;
 		return IIO_VAL_INT;
 	default:
 		return -EINVAL;
@@ -630,14 +661,24 @@ static const struct iio_chan_spec bma250_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(4),
 };
 
+static const struct iio_chan_spec bma254_channels[] = {
+	BMA180_ACC_CHANNEL(X, 12),
+	BMA180_ACC_CHANNEL(Y, 12),
+	BMA180_ACC_CHANNEL(Z, 12),
+	BMA180_TEMP_CHANNEL,
+	IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
 static const struct bma180_part_info bma180_part_info[] = {
 	[BMA180] = {
+		.chip_id = BMA180_ID_REG_VAL,
 		.channels = bma180_channels,
 		.num_channels = ARRAY_SIZE(bma180_channels),
 		.scale_table = bma180_scale_table,
 		.num_scales = ARRAY_SIZE(bma180_scale_table),
 		.bw_table = bma180_bw_table,
 		.num_bw = ARRAY_SIZE(bma180_bw_table),
+		.center_temp = 48, /* 0 LSB @ 24 degree C */
 		.int_reset_reg = BMA180_CTRL_REG0,
 		.int_reset_mask = BMA180_RESET_INT,
 		.sleep_reg = BMA180_CTRL_REG0,
@@ -656,12 +697,14 @@ static const struct bma180_part_info bma180_part_info[] = {
 		.chip_disable = bma180_chip_disable,
 	},
 	[BMA250] = {
+		.chip_id = BMA250_ID_REG_VAL,
 		.channels = bma250_channels,
 		.num_channels = ARRAY_SIZE(bma250_channels),
-		.scale_table = bma250_scale_table,
-		.num_scales = ARRAY_SIZE(bma250_scale_table),
-		.bw_table = bma250_bw_table,
-		.num_bw = ARRAY_SIZE(bma250_bw_table),
+		.scale_table = bma25x_scale_table,
+		.num_scales = ARRAY_SIZE(bma25x_scale_table),
+		.bw_table = bma25x_bw_table,
+		.num_bw = ARRAY_SIZE(bma25x_bw_table),
+		.center_temp = 48, /* 0 LSB @ 24 degree C */
 		.int_reset_reg = BMA250_INT_RESET_REG,
 		.int_reset_mask = BMA250_INT_RESET_MASK,
 		.sleep_reg = BMA250_POWER_REG,
@@ -675,9 +718,39 @@ static const struct bma180_part_info bma180_part_info[] = {
 		.lowpower_val = 1,
 		.int_enable_reg = BMA250_INT_ENABLE_REG,
 		.int_enable_mask = BMA250_DATA_INTEN_MASK,
+		.int_map_reg = BMA250_INT_MAP_REG,
+		.int_enable_dataready_int1_mask = BMA250_INT1_DATA_MASK,
 		.softreset_reg = BMA250_RESET_REG,
-		.chip_config = bma250_chip_config,
-		.chip_disable = bma250_chip_disable,
+		.chip_config = bma25x_chip_config,
+		.chip_disable = bma25x_chip_disable,
+	},
+	[BMA254] = {
+		.chip_id = BMA254_ID_REG_VAL,
+		.channels = bma254_channels,
+		.num_channels = ARRAY_SIZE(bma254_channels),
+		.scale_table = bma25x_scale_table,
+		.num_scales = ARRAY_SIZE(bma25x_scale_table),
+		.bw_table = bma25x_bw_table,
+		.num_bw = ARRAY_SIZE(bma25x_bw_table),
+		.center_temp = 46, /* 0 LSB @ 23 degree C */
+		.int_reset_reg = BMA254_INT_RESET_REG,
+		.int_reset_mask = BMA254_INT_RESET_MASK,
+		.sleep_reg = BMA254_POWER_REG,
+		.sleep_mask = BMA254_SUSPEND_MASK,
+		.bw_reg = BMA254_BW_REG,
+		.bw_mask = BMA254_BW_MASK,
+		.scale_reg = BMA254_RANGE_REG,
+		.scale_mask = BMA254_RANGE_MASK,
+		.power_reg = BMA254_POWER_REG,
+		.power_mask = BMA254_LOWPOWER_MASK,
+		.lowpower_val = 1,
+		.int_enable_reg = BMA254_INT_ENABLE_REG,
+		.int_enable_mask = BMA254_DATA_INTEN_MASK,
+		.int_map_reg = BMA254_INT_MAP_REG,
+		.int_enable_dataready_int1_mask = BMA254_INT1_DATA_MASK,
+		.softreset_reg = BMA254_RESET_REG,
+		.chip_config = bma25x_chip_config,
+		.chip_disable = bma25x_chip_disable,
 	},
 };
 
@@ -919,6 +992,7 @@ static SIMPLE_DEV_PM_OPS(bma180_pm_ops, bma180_suspend, bma180_resume);
 static const struct i2c_device_id bma180_ids[] = {
 	{ "bma180", BMA180 },
 	{ "bma250", BMA250 },
+	{ "bma254", BMA254 },
 	{ }
 };
 
@@ -933,6 +1007,10 @@ static const struct of_device_id bma180_of_match[] = {
 		.compatible = "bosch,bma250",
 		.data = (void *)BMA250
 	},
+	{
+		.compatible = "bosch,bma254",
+		.data = (void *)BMA254
+	},
 	{ }
 };
 MODULE_DEVICE_TABLE(of, bma180_of_match);
@@ -952,5 +1030,5 @@ module_i2c_driver(bma180_driver);
 
 MODULE_AUTHOR("Kravchenko Oleksandr <x0199363@ti.com>");
 MODULE_AUTHOR("Texas Instruments, Inc.");
-MODULE_DESCRIPTION("Bosch BMA180/BMA250 triaxial acceleration sensor");
+MODULE_DESCRIPTION("Bosch BMA180/BMA25x triaxial acceleration sensor");
 MODULE_LICENSE("GPL");