iio: imu: bmi270: Add support for BMI260

Adds support for the Bosch BMI260 6-axis IMU to the Bosch BMI270
driver. Setup and operation is nearly identical to the Bosch BMI270,
but has a different chip ID and requires different firmware.

Firmware is requested and loaded from userspace.

Adds ACPI ID BMI0160, used by several devices including the GPD Win
Mini, Aya Neo AIR Pro, and OXP Mini Pro.

GPD Win Mini:

Device (BMI2)
{
    Name (_ADR, Zero)  // _ADR: Address
    Name (_HID, "BMI0160")  // _HID: Hardware ID
    Name (_CID, "BMI0160")  // _CID: Compatible ID
    Name (_DDN, "Accelerometer")  // _DDN: DOS Device Name
    Name (_UID, One)  // _UID: Unique ID
    Method (_CRS, 0, NotSerialized)  // _CRS: Current Resource Settings
    {
        Name (RBUF, ResourceTemplate ()
        {
            I2cSerialBusV2 (0x0068, ControllerInitiated, 0x00061A80,
                AddressingMode7Bit, "\\_SB.I2CB",
                0x00, ResourceConsumer, , Exclusive,
                )
            GpioInt (Edge, ActiveLow, Exclusive, PullDefault, 0x0000,
                "\\_SB.GPIO", 0x00, ResourceConsumer, ,
                )
                {   // Pin list
                    0x008B
                }
        })
        Return (RBUF) /* \_SB_.I2CB.BMI2._CRS.RBUF */
    }
    ...
}

Signed-off-by: Justin Weiss <justin@justinweiss.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20241027172029.160134-5-justin@justinweiss.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/bmi270/bmi270.h

@@ -29,6 +29,7 @@ struct bmi270_chip_info {
 };
 
 extern const struct regmap_config bmi270_regmap_config;
+extern const struct bmi270_chip_info bmi260_chip_info;
 extern const struct bmi270_chip_info bmi270_chip_info;
 
 int bmi270_core_probe(struct device *dev, struct regmap *regmap,

drivers/iio/imu/bmi270/bmi270_core.c

@@ -14,6 +14,11 @@
 #include "bmi270.h"
 
 #define BMI270_CHIP_ID_REG				0x00
+
+/* Checked to prevent sending incompatible firmware to BMI160 devices */
+#define BMI160_CHIP_ID_VAL				0xD1
+
+#define BMI260_CHIP_ID_VAL				0x27
 #define BMI270_CHIP_ID_VAL				0x24
 #define BMI270_CHIP_ID_MSK				GENMASK(7, 0)
 
@@ -64,6 +69,7 @@
 #define BMI270_PWR_CTRL_ACCEL_EN_MSK			BIT(2)
 #define BMI270_PWR_CTRL_TEMP_EN_MSK			BIT(3)
 
+#define BMI260_INIT_DATA_FILE "bmi260-init-data.fw"
 #define BMI270_INIT_DATA_FILE "bmi270-init-data.fw"
 
 enum bmi270_scan {
@@ -86,6 +92,13 @@ static const unsigned long bmi270_avail_scan_masks[] = {
 	0
 };
 
+const struct bmi270_chip_info bmi260_chip_info = {
+	.name = "bmi260",
+	.chip_id = BMI260_CHIP_ID_VAL,
+	.fw_name = BMI260_INIT_DATA_FILE,
+};
+EXPORT_SYMBOL_NS_GPL(bmi260_chip_info, IIO_BMI270);
+
 const struct bmi270_chip_info bmi270_chip_info = {
 	.name = "bmi270",
 	.chip_id = BMI270_CHIP_ID_VAL,
@@ -545,8 +558,21 @@ static int bmi270_validate_chip_id(struct bmi270_data *bmi270_device)
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to read chip id");
 
+	/*
+	 * Some manufacturers use "BMI0160" for both the BMI160 and
+	 * BMI260. If the device is actually a BMI160, the bmi160
+	 * driver should handle it and this driver should not.
+	 */
+	if (chip_id == BMI160_CHIP_ID_VAL)
+		return -ENODEV;
+
 	if (chip_id != bmi270_device->chip_info->chip_id)
-		dev_info(dev, "Unknown chip id 0x%x", chip_id);
+		dev_info(dev, "Unexpected chip id 0x%x", chip_id);
+
+	if (chip_id == bmi260_chip_info.chip_id)
+		bmi270_device->chip_info = &bmi260_chip_info;
+	else if (chip_id == bmi270_chip_info.chip_id)
+		bmi270_device->chip_info = &bmi270_chip_info;
 
 	return 0;
 }

drivers/iio/imu/bmi270/bmi270_i2c.c

@@ -32,18 +32,27 @@ static int bmi270_i2c_probe(struct i2c_client *client)
 }
 
 static const struct i2c_device_id bmi270_i2c_id[] = {
+	{ "bmi260", (kernel_ulong_t)&bmi260_chip_info },
 	{ "bmi270", (kernel_ulong_t)&bmi270_chip_info },
 	{ }
 };
 
+static const struct acpi_device_id bmi270_acpi_match[] = {
+	/* GPD Win Mini, Aya Neo AIR Pro, OXP Mini Pro, etc. */
+	{ "BMI0160",  (kernel_ulong_t)&bmi260_chip_info },
+	{ }
+};
+
 static const struct of_device_id bmi270_of_match[] = {
+	{ .compatible = "bosch,bmi260", .data = &bmi260_chip_info },
 	{ .compatible = "bosch,bmi270", .data = &bmi270_chip_info },
 	{ }
 };
 
 static struct i2c_driver bmi270_i2c_driver = {
 	.driver = {
 		.name = "bmi270_i2c",
+		.acpi_match_table = bmi270_acpi_match,
 		.of_match_table = bmi270_of_match,
 	},
 	.probe = bmi270_i2c_probe,

drivers/iio/imu/bmi270/bmi270_spi.c

@@ -65,11 +65,13 @@ static int bmi270_spi_probe(struct spi_device *spi)
 }
 
 static const struct spi_device_id bmi270_spi_id[] = {
+	{ "bmi260", (kernel_ulong_t)&bmi260_chip_info },
 	{ "bmi270", (kernel_ulong_t)&bmi270_chip_info },
 	{ }
 };
 
 static const struct of_device_id bmi270_of_match[] = {
+	{ .compatible = "bosch,bmi260", .data = &bmi260_chip_info },
 	{ .compatible = "bosch,bmi270", .data = &bmi270_chip_info },
 	{ }
 };