[PATCH 1/3] iio: pressure: bmp280: add initial support for multiple chips

[Matt Ranostay <matt.ranostay@intel.com>]

Bosch has several chipsets that use BMP280 as core features, this enables
chip information for each variant.

Signed-off-by: Matt Ranostay <matt.ranostay@intel.com>
---
 drivers/iio/pressure/bmp280.c | 59 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 54 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/pressure/bmp280.c b/drivers/iio/pressure/bmp280.c
index a2602d8dd6d5..2e7cff38f5ff 100644
--- a/drivers/iio/pressure/bmp280.c
+++ b/drivers/iio/pressure/bmp280.c
@@ -66,12 +66,15 @@
 #define BMP280_MODE_NORMAL		(BIT(1) | BIT(0))
 
 #define BMP280_CHIP_ID			0x58
+#define BME280_CHIP_ID			0x60
+
 #define BMP280_SOFT_RESET_VAL		0xB6
 
 struct bmp280_data {
 	struct i2c_client *client;
 	struct mutex lock;
 	struct regmap *regmap;
+	struct bmp280_chip_info *chip;
 
 	/*
 	 * Carryover value from temperature conversion, used in pressure
@@ -80,6 +83,24 @@ struct bmp280_data {
 	s32 t_fine;
 };
 
+enum { bmp280, bme280 };
+
+struct bmp280_chip_info {
+	int id;
+	int num_channels;
+};
+
+static struct bmp280_chip_info bmp280_chip_info_table[] = {
+	[bmp280] = {
+		.id = BMP280_CHIP_ID,
+		.num_channels = 2,
+	},
+	[bme280] = {
+		.id = BME280_CHIP_ID,
+		.num_channels = 2,
+	},
+};
+
 /*
  * These enums are used for indexing into the array of compensation
  * parameters.
@@ -344,6 +365,20 @@ static int bmp280_chip_init(struct bmp280_data *data)
 	return ret;
 }
 
+static int bmp280_match_acpi_device(struct device *dev,
+				    struct bmp280_chip_info **chipset)
+{
+	const struct acpi_device_id *id;
+
+	id = acpi_match_device(dev->driver->acpi_match_table, dev);
+	if (!id)
+		return -ENODEV;
+
+	*chipset = &bmp280_chip_info_table[id->driver_data];
+
+	return 0;
+}
+
 static int bmp280_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
@@ -357,13 +392,25 @@ static int bmp280_probe(struct i2c_client *client,
 		return -ENOMEM;
 
 	data = iio_priv(indio_dev);
+
+	if (id) {
+		data->chip = &bmp280_chip_info_table[id->driver_data];
+	} else if (ACPI_HANDLE(&client->dev)) {
+		ret = bmp280_match_acpi_device(&client->dev, &data->chip);
+		if (ret < 0)
+			return ret;
+	} else {
+		/* Don't break sysfs registration of BMP280 devices */
+		data->chip = &bmp280_chip_info_table[bmp280];
+	}
+
 	mutex_init(&data->lock);
 	data->client = client;
 
 	indio_dev->dev.parent = &client->dev;
 	indio_dev->name = id->name;
 	indio_dev->channels = bmp280_channels;
-	indio_dev->num_channels = ARRAY_SIZE(bmp280_channels);
+	indio_dev->num_channels = data->chip->num_channels;
 	indio_dev->info = &bmp280_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
@@ -376,9 +423,9 @@ static int bmp280_probe(struct i2c_client *client,
 	ret = regmap_read(data->regmap, BMP280_REG_ID, &chip_id);
 	if (ret < 0)
 		return ret;
-	if (chip_id != BMP280_CHIP_ID) {
+	if (chip_id != data->chip->id) {
 		dev_err(&client->dev, "bad chip id.  expected %x got %x\n",
-			BMP280_CHIP_ID, chip_id);
+			data->chip->id, chip_id);
 		return -EINVAL;
 	}
 
@@ -390,13 +437,15 @@ static int bmp280_probe(struct i2c_client *client,
 }
 
 static const struct acpi_device_id bmp280_acpi_match[] = {
-	{"BMP0280", 0},
+	{"BMP0280", bmp280},
+	{"BME0280", bme280},
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, bmp280_acpi_match);
 
 static const struct i2c_device_id bmp280_id[] = {
-	{"bmp280", 0},
+	{"bmp280", bmp280},
+	{"bme280", bme280},
 	{ },
 };
 MODULE_DEVICE_TABLE(i2c, bmp280_id);
-- 
1.9.1