From a8175ba33542d625430b66a805ef315ea3b4e755 Mon Sep 17 00:00:00 2001 From: Crestez Dan Leonard Date: Fri, 29 Apr 2016 22:05:32 +0300 Subject: [PATCH] iio: ak8975: Support adapters limited to BYTE_DATA The device has simple 8-bit registers but the driver incorrectly uses block or word reads without checking functionality bits. Fix by using i2c_smbus_read_i2c_block_data_or_emulated instead of i2c_smbus_read_i2c_block_data or i2c_smbus_read_word_data. This will check functionality bits and use the fastest available transfer method. Signed-off-by: Crestez Dan Leonard Signed-off-by: Jonathan Cameron --- drivers/iio/magnetometer/ak8975.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c index dbf066129a04..c24b8a509ed8 100644 --- a/drivers/iio/magnetometer/ak8975.c +++ b/drivers/iio/magnetometer/ak8975.c @@ -430,8 +430,8 @@ static int ak8975_who_i_am(struct i2c_client *client, * AK8975 | DEVICE_ID | NA * AK8963 | DEVICE_ID | NA */ - ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1, - 2, wia_val); + ret = i2c_smbus_read_i2c_block_data_or_emulated( + client, AK09912_REG_WIA1, 2, wia_val); if (ret < 0) { dev_err(&client->dev, "Error reading WIA\n"); return ret; @@ -543,9 +543,9 @@ static int ak8975_setup(struct i2c_client *client) } /* Get asa data and store in the device data. */ - ret = i2c_smbus_read_i2c_block_data(client, - data->def->ctrl_regs[ASA_BASE], - 3, data->asa); + ret = i2c_smbus_read_i2c_block_data_or_emulated( + client, data->def->ctrl_regs[ASA_BASE], + 3, data->asa); if (ret < 0) { dev_err(&client->dev, "Not able to read asa data\n"); return ret; @@ -686,6 +686,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val) struct ak8975_data *data = iio_priv(indio_dev); const struct i2c_client *client = data->client; const struct ak_def *def = data->def; + u16 buff; int ret; mutex_lock(&data->lock); @@ -694,14 +695,17 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val) if (ret) goto exit; - ret = i2c_smbus_read_word_data(client, def->data_regs[index]); + ret = i2c_smbus_read_i2c_block_data_or_emulated( + client, def->data_regs[index], + sizeof(buff), (u8*)&buff); if (ret < 0) goto exit; mutex_unlock(&data->lock); - /* Clamp to valid range. */ - *val = clamp_t(s16, ret, -def->range, def->range); + /* Swap bytes and convert to valid range. */ + buff = le16_to_cpu(buff); + *val = clamp_t(s16, buff, -def->range, def->range); return IIO_VAL_INT; exit: -- 2.20.1