diff options
| -rw-r--r-- | drivers/iio/accel/mma8452.c | 37 |
1 files changed, 33 insertions, 4 deletions
diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c index 5b80657883bb..001a7dbc863c 100644 --- a/drivers/iio/accel/mma8452.c +++ b/drivers/iio/accel/mma8452.c @@ -32,6 +32,7 @@ #define MMA8452_OFF_Z 0x31 #define MMA8452_CTRL_REG1 0x2a #define MMA8452_CTRL_REG2 0x2b +#define MMA8452_CTRL_REG2_RST BIT(6) #define MMA8452_STATUS_DRDY (BIT(2) | BIT(1) | BIT(0)) @@ -335,6 +336,30 @@ static const struct iio_info mma8452_info = { static const unsigned long mma8452_scan_masks[] = {0x7, 0}; +static int mma8452_reset(struct i2c_client *client) +{ + int i; + int ret; + + ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG2, + MMA8452_CTRL_REG2_RST); + if (ret < 0) + return ret; + + for (i = 0; i < 10; i++) { + usleep_range(100, 200); + ret = i2c_smbus_read_byte_data(client, MMA8452_CTRL_REG2); + if (ret == -EIO) + continue; /* I2C comm reset */ + if (ret < 0) + return ret; + if (!(ret & MMA8452_CTRL_REG2_RST)) + return 0; + } + + return -ETIMEDOUT; +} + static int mma8452_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -365,10 +390,7 @@ static int mma8452_probe(struct i2c_client *client, indio_dev->num_channels = ARRAY_SIZE(mma8452_channels); indio_dev->available_scan_masks = mma8452_scan_masks; - data->ctrl_reg1 = MMA8452_CTRL_ACTIVE | - (MMA8452_CTRL_DR_DEFAULT << MMA8452_CTRL_DR_SHIFT); - ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1, - data->ctrl_reg1); + ret = mma8452_reset(client); if (ret < 0) return ret; @@ -378,6 +400,13 @@ static int mma8452_probe(struct i2c_client *client, if (ret < 0) return ret; + data->ctrl_reg1 = MMA8452_CTRL_ACTIVE | + (MMA8452_CTRL_DR_DEFAULT << MMA8452_CTRL_DR_SHIFT); + ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1, + data->ctrl_reg1); + if (ret < 0) + return ret; + ret = iio_triggered_buffer_setup(indio_dev, NULL, mma8452_trigger_handler, NULL); if (ret < 0) |