staging: iio: cdc: ad7746: Use local buffer for multi byte reads.

I2C does not require DMA safe buffers so there is no need to ensure
the buffers are in their own cacheline. Hence simplify things by
using a local variable instead of embedding the buffer in the chip
info structure.

Includes a trivial whitespace cleanup to drop a line between function
and error handling.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220626122938.582107-6-jic23@kernel.org

diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
index 0b5cb788abee76eca48d8c9a4dfeef7e6dccdff2..496e90f559c7d964049eeae64e22270c122830a2 100644 (file)
--- a/drivers/staging/iio/cdc/ad7746.c
+++ b/drivers/staging/iio/cdc/ad7746.c
@@ -96,8 +96,6 @@ struct ad7746_chip_info {
        u8      vt_setup;
        u8      capdac[2][2];
        s8      capdac_set;
-
-       u8 data[3] ____cacheline_aligned;
 };
 
 enum ad7746_chan {
@@ -522,6 +520,7 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
        struct ad7746_chip_info *chip = iio_priv(indio_dev);
        int ret, delay, idx;
        u8 regval, reg;
+       u8 data[3];
 
        mutex_lock(&chip->lock);
 
@@ -544,13 +543,11 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
 
                ret = i2c_smbus_read_i2c_block_data(chip->client,
                                                    chan->address >> 8,
-                                                   sizeof(chip->data),
-                                                   chip->data);
-
+                                                   sizeof(data), data);
                if (ret < 0)
                        goto out;
 
-               *val = get_unaligned_be24(chip->data) - 0x800000;
+               *val = get_unaligned_be24(data) - 0x800000;
 
                switch (chan->type) {
                case IIO_TEMP: