[PATCH 2/2] iio: imu: inv_mpu6050: Add support for MPU-6880

[Stephan Gerhold <stephan@gerhold.net>]

MPU-6880 seems to be very similar to MPU-6500 / MPU-6050 and it works
fine with some minor additions for the mpu6050 driver.

Add the necessary defines for it and make it use the same registers as
MPU-6500 but with a FIFO size of 4096.

Cc: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
I tested this on a Xiaomi Redmi 2 (or Wingtech WT88047).

Unfortunately I was not able to find a proper register description
for MPU-6880. :( It seems to work fine with both 6050 or 6500 registers
but I guess that it is more similar to MPU-6500. Not sure though.

I'm mainly unsure about
	.accl_offset		= INV_MPU6500_REG_ACCEL_OFFSET,
vs
	.accl_offset		= INV_MPU6050_REG_ACCEL_OFFSET,

Both registers read some funny values but I cannot say which one
is more appropriate...

Perhaps Jean-Baptiste can shed some light on this? :)
---
 drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 9 +++++++++
 drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c  | 5 +++++
 drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h  | 2 ++
 drivers/iio/imu/inv_mpu6050/inv_mpu_spi.c  | 5 +++++
 4 files changed, 21 insertions(+)

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index 18a1898e3e34..453c51c79655 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -160,6 +160,14 @@ static const struct inv_mpu6050_hw hw_info[] = {
 		.fifo_size = 512,
 		.temp = {INV_MPU6500_TEMP_OFFSET, INV_MPU6500_TEMP_SCALE},
 	},
+	{
+		.whoami = INV_MPU6880_WHOAMI_VALUE,
+		.name = "MPU6880",
+		.reg = &reg_set_6500,
+		.config = &chip_config_6500,
+		.fifo_size = 4096,
+		.temp = {INV_MPU6500_TEMP_OFFSET, INV_MPU6500_TEMP_SCALE},
+	},
 	{
 		.whoami = INV_MPU6000_WHOAMI_VALUE,
 		.name = "MPU6000",
@@ -1323,6 +1331,7 @@ static int inv_check_and_setup_chip(struct inv_mpu6050_state *st)
 	case INV_MPU6000:
 	case INV_MPU6500:
 	case INV_MPU6515:
+	case INV_MPU6880:
 	case INV_MPU9250:
 	case INV_MPU9255:
 		/* reset signal path (required for spi connection) */
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c
index 28cfae1e61cf..95f16951c8f4 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c
@@ -177,6 +177,7 @@ static const struct i2c_device_id inv_mpu_id[] = {
 	{"mpu6050", INV_MPU6050},
 	{"mpu6500", INV_MPU6500},
 	{"mpu6515", INV_MPU6515},
+	{"mpu6880", INV_MPU6880},
 	{"mpu9150", INV_MPU9150},
 	{"mpu9250", INV_MPU9250},
 	{"mpu9255", INV_MPU9255},
@@ -204,6 +205,10 @@ static const struct of_device_id inv_of_match[] = {
 		.compatible = "invensense,mpu6515",
 		.data = (void *)INV_MPU6515
 	},
+	{
+		.compatible = "invensense,mpu6880",
+		.data = (void *)INV_MPU6880
+	},
 	{
 		.compatible = "invensense,mpu9150",
 		.data = (void *)INV_MPU9150
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
index eb522b38acf3..58188dc0dd13 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
@@ -70,6 +70,7 @@ enum inv_devices {
 	INV_MPU6050,
 	INV_MPU6500,
 	INV_MPU6515,
+	INV_MPU6880,
 	INV_MPU6000,
 	INV_MPU9150,
 	INV_MPU9250,
@@ -373,6 +374,7 @@ struct inv_mpu6050_state {
 #define INV_MPU6000_WHOAMI_VALUE		0x68
 #define INV_MPU6050_WHOAMI_VALUE		0x68
 #define INV_MPU6500_WHOAMI_VALUE		0x70
+#define INV_MPU6880_WHOAMI_VALUE		0x78
 #define INV_MPU9150_WHOAMI_VALUE		0x68
 #define INV_MPU9250_WHOAMI_VALUE		0x71
 #define INV_MPU9255_WHOAMI_VALUE		0x73
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_spi.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_spi.c
index 6f968ce687e1..b056f3fe2561 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_spi.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_spi.c
@@ -70,6 +70,7 @@ static const struct spi_device_id inv_mpu_id[] = {
 	{"mpu6000", INV_MPU6000},
 	{"mpu6500", INV_MPU6500},
 	{"mpu6515", INV_MPU6515},
+	{"mpu6880", INV_MPU6880},
 	{"mpu9250", INV_MPU9250},
 	{"mpu9255", INV_MPU9255},
 	{"icm20608", INV_ICM20608},
@@ -96,6 +97,10 @@ static const struct of_device_id inv_of_match[] = {
 		.compatible = "invensense,mpu6515",
 		.data = (void *)INV_MPU6515
 	},
+	{
+		.compatible = "invensense,mpu6880",
+		.data = (void *)INV_MPU6880
+	},
 	{
 		.compatible = "invensense,mpu9250",
 		.data = (void *)INV_MPU9250
-- 
2.29.2