On 2016-04-29 21:02, Crestez Dan Leonard wrote: > The MPU has an auxiliary I2C bus for connecting external > sensors. This bus has two operating modes: > * pass-through, which connects the primary and auxiliary busses > together. This is already supported via an i2c mux. > * I2C master mode, where the mpu60x0 acts as a master to any external > connected sensors. This is implemented by this patch. > > This I2C master mode also works when the MPU itself is connected via > SPI. > > I2C master supports up to 5 slaves. Slaves 0-3 have a common operating > mode while slave 4 is different. This patch implements an i2c adapter > using slave 4 because it has a cleaner interface and it has an > interrupt that signals when data from slave to master arrived. > > Signed-off-by: Crestez Dan Leonard <leonard.crestez@xxxxxxxxx> > --- > .../devicetree/bindings/iio/imu/inv_mpu6050.txt | 61 +++++- > drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 239 ++++++++++++++++++++- > drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h | 46 ++++ > drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c | 8 - > 4 files changed, 341 insertions(+), 13 deletions(-) > > diff --git a/Documentation/devicetree/bindings/iio/imu/inv_mpu6050.txt b/Documentation/devicetree/bindings/iio/imu/inv_mpu6050.txt > index a9fc11e..aaf12b4 100644 > --- a/Documentation/devicetree/bindings/iio/imu/inv_mpu6050.txt > +++ b/Documentation/devicetree/bindings/iio/imu/inv_mpu6050.txt > @@ -1,16 +1,27 @@ > InvenSense MPU-6050 Six-Axis (Gyro + Accelerometer) MEMS MotionTracking Device > > -http://www.invensense.com/mems/gyro/mpu6050.html > - > Required properties: > - - compatible : should be "invensense,mpu6050" > - - reg : the I2C address of the sensor > + - compatible : should be "invensense,mpuXXXX" > + - reg : the I2C or SPI address of the sensor > - interrupt-parent : should be the phandle for the interrupt controller > - interrupts : interrupt mapping for GPIO IRQ > > Optional properties: > - mount-matrix: an optional 3x3 mounting rotation matrix > + - inv,i2c-aux-master: operate aux i2c in "master mode" (default is mux). I've looked a bit more into this, and I don't think you need this property... > + > +Valid compatible strings: > + - mpu6000 > + - mpu6050 > + - mpu6500 > + - mpu9150 > + > +It is possible to attach auxiliary sensors to the MPU and have them be handled > +by linux. Those auxiliary sensors are described as an i2c bus. > + > +Devices connected in "bypass" mode must be listed behind i2c@0 with the address 0 > > +Devices connected in "master" mode must be listed behind i2c@1 with the address 1 ...and just condition the new stuff on the name i2c-master instead. If there is no i2c-master child, then fall back to the mux code. Does that work? > Example: > mpu6050@68 { > @@ -28,3 +39,45 @@ Example: > "0", /* y2 */ > "0.984807753012208"; /* z2 */ > }; > + > +Example describing mpu9150 (which includes an ak9875 on chip): > + mpu9150@68 { > + compatible = "invensense,mpu9150"; > + reg = <0x68>; > + interrupt-parent = <&gpio1>; > + interrupts = <18 1>; > + > + #address-cells = <1>; > + #size-cells = <0>; > + i2c@0 { > + reg = <0>; > + #address-cells = <1>; > + #size-cells = <0>; > + > + ak8975@0c { > + compatible = "ak,ak8975"; > + reg = <0x0c>; > + }; > + }; > + }; > + > +Example describing a mpu6500 via SPI with an hmc5883l on auxiliary i2c: > + mpu6500@0 { > + compatible = "inv,mpu6500"; > + reg = <0x0>; > + spi-max-frequency = <1000000>; > + interrupt-parent = <&gpio1>; > + interrupts = <31 1>; > + > + inv,i2c-aux-master If you keep the below as i2c@1, including the @, I think you also need #address-cells = <1>; #size-cells = <0>; As always, I'm not a device tree expert, but I'd be glad to lose these extra lines and change i2c@1 into i2c-master. > + i2c@1 { > + reg = <1>; > + #address-cells = <1>; > + #size-cells = <0>; > + > + hmc5883l@1e { > + compatible = "honeywell,hmc5883l"; > + reg = <0x1e>; > + }; > + }; > + }; *snip* Cheers, Peter -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
