Re: [PATCH v3 4/6] iio: imu: bmi270: Add support for BMI260

[Justin Weiss <justin@justinweiss.com>]

Justin Weiss <justin@justinweiss.com> writes:

> 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.
>
> Signed-off-by: Justin Weiss <justin@justinweiss.com>
> ---
>  drivers/iio/imu/bmi270/bmi270.h      |  1 +
>  drivers/iio/imu/bmi270/bmi270_core.c | 28 +++++++++++++++++++++++++++-
>  drivers/iio/imu/bmi270/bmi270_i2c.c  | 13 +++++++++++++
>  drivers/iio/imu/bmi270/bmi270_spi.c  |  8 ++++++++
>  4 files changed, 49 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/imu/bmi270/bmi270.h b/drivers/iio/imu/bmi270/bmi270.h
> index 93e5f387607b..d8f6d7cf47fc 100644
> --- a/drivers/iio/imu/bmi270/bmi270.h
> +++ b/drivers/iio/imu/bmi270/bmi270.h
> @@ -20,6 +20,7 @@ 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,
> diff --git a/drivers/iio/imu/bmi270/bmi270_core.c b/drivers/iio/imu/bmi270/bmi270_core.c
> index 5f08d786fa21..24e45d6f0706 100644
> --- a/drivers/iio/imu/bmi270/bmi270_core.c
> +++ b/drivers/iio/imu/bmi270/bmi270_core.c
> @@ -11,6 +11,11 @@
>  #include "bmi270.h"
>  
>  #define BMI270_CHIP_ID_REG				0x00
> +
> +/* Used 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)
>  
> @@ -55,6 +60,7 @@
>  #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 {
> @@ -66,6 +72,13 @@ enum bmi270_scan {
>  	BMI270_SCAN_GYRO_Z,
>  };
>  
> +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,
> @@ -157,8 +170,21 @@ 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;
>  }
> diff --git a/drivers/iio/imu/bmi270/bmi270_i2c.c b/drivers/iio/imu/bmi270/bmi270_i2c.c
> index 394f27996059..3d0d8f3e8b63 100644
> --- a/drivers/iio/imu/bmi270/bmi270_i2c.c
> +++ b/drivers/iio/imu/bmi270/bmi270_i2c.c
> @@ -32,11 +32,23 @@ 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 },
>  	{ }
>  };
>

The ACPI IDs with device pointers are here:

> +static const struct acpi_device_id bmi270_acpi_match[] = {
> +	/* OrangePi NEO */
> +	{ "BMI0260",  (kernel_ulong_t)&bmi260_chip_info },
> +	/* GPD Win Mini, Aya Neo AIR Pro, OXP Mini Pro, etc. */
> +	{ "BMI0160",  (kernel_ulong_t)&bmi260_chip_info },
> +	/* GPD Win Max 2 */
> +	{ "10EC5280", (kernel_ulong_t)&bmi260_chip_info },
> +	{ }
> +};

I pulled DSDT device excerpts for the GPD Win Mini (which uses the
BMI0160 ACPI ID, even though it has a bmi260) and the OrangePi NEO
(which uses the BMI0260 ACPI ID).

I couldn't find a shipping device with a bmi260 using the 10EC5280 ACPI
ID. Some prototype devices with the bmi260 may have used them:
https://lore.kernel.org/all/CAFqHKTm2WRNkcSoBEE=oNbfu_9d9RagQHLydmv6q1=snO_MXyA@mail.gmail.com/

I can remove that ID from this changeset for now.


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 */
    }

    OperationRegion (CMS2, SystemIO, 0x72, 0x02)
    Field (CMS2, ByteAcc, NoLock, Preserve)
    {
        IND2,   8, 
        DAT2,   8
    }

    IndexField (IND2, DAT2, ByteAcc, NoLock, Preserve)
    {
        Offset (0x74), 
        BACS,   32
    }

    Method (ROMS, 0, NotSerialized)
    {
        Name (RBUF, Package (0x03)
        {
            "0 1 0", 
            "1 0 0", 
            "0 0 1"
        })
        Return (RBUF) /* \_SB_.I2CB.BMI2.ROMS.RBUF */
    }

    Method (CALS, 1, NotSerialized)
    {
        Local0 = Arg0
        If (((Local0 == Zero) || (Local0 == Ones)))
        {
            Return (Local0)
        }
        Else
        {
            BACS = Local0
        }
    }

    Method (_STA, 0, NotSerialized)  // _STA: Status
    {
        Return (0x0F)
    }
}


OrangePi NEO:

Device (BMI2)
{
    Name (_ADR, Zero)  // _ADR: Address
    Name (_HID, "BMI0260")  // _HID: Hardware ID
    Name (_CID, "BMI0260")  // _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 */
    }

    OperationRegion (CMS2, SystemIO, 0x72, 0x02)
    Field (CMS2, ByteAcc, NoLock, Preserve)
    {
        IND2,   8, 
        DAT2,   8
    }

    IndexField (IND2, DAT2, ByteAcc, NoLock, Preserve)
    {
        Offset (0x74), 
        BACS,   32
    }

    Method (ROMS, 0, NotSerialized)
    {
        Name (RBUF, Package (0x03)
        {
            "0 1 0", 
            "1 0 0", 
            "0 0 1"
        })
        Return (RBUF) /* \_SB_.I2CB.BMI2.ROMS.RBUF */
    }

    Method (CALS, 1, NotSerialized)
    {
        Local0 = Arg0
        If (((Local0 == Zero) || (Local0 == Ones)))
        {
            Return (Local0)
        }
        Else
        {
            BACS = Local0
        }
    }

    Method (_STA, 0, NotSerialized)  // _STA: Status
    {
        Return (0x0F)
    }
}

> +
>  static const struct of_device_id bmi270_of_match[] = {
> +	{ .compatible = "bosch,bmi260", .data = &bmi260_chip_info },
>  	{ .compatible = "bosch,bmi270", .data = &bmi270_chip_info },
>  	{ }
>  };
> @@ -44,6 +56,7 @@ static const struct of_device_id bmi270_of_match[] = {
>  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,
> diff --git a/drivers/iio/imu/bmi270/bmi270_spi.c b/drivers/iio/imu/bmi270/bmi270_spi.c
> index 7c2062c660d9..7f42ed74023b 100644
> --- a/drivers/iio/imu/bmi270/bmi270_spi.c
> +++ b/drivers/iio/imu/bmi270/bmi270_spi.c
> @@ -65,11 +65,18 @@ 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 acpi_device_id bmi270_acpi_match[] = {
> +	{ "BOSC0260",  (kernel_ulong_t)&bmi260_chip_info },
> +	{ }
> +};
> +

I can't find any evidence of BOSC0260 being used, besides existing in
the Windows driver. As suggested in an earlier review, I added it here
to encourage people looking at this driver in the future to use the
correct ACPI ID.

Thanks,
Justin

>  static const struct of_device_id bmi270_of_match[] = {
> +	{ .compatible = "bosch,bmi260", .data = &bmi260_chip_info },
>  	{ .compatible = "bosch,bmi270", .data = &bmi270_chip_info },
>  	{ }
>  };
> @@ -77,6 +84,7 @@ static const struct of_device_id bmi270_of_match[] = {
>  static struct spi_driver bmi270_spi_driver = {
>  	.driver = {
>  		.name = "bmi270",
> +		.acpi_match_table = bmi270_acpi_match,
>  		.of_match_table = bmi270_of_match,
>  	},
>  	.probe = bmi270_spi_probe,