iio: prox: pulsed-light: Fix buffer alignment in iio_push_to_buffers_with_timestamp()

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.

Found during an audit of all calls of uses of
iio_push_to_buffers_with_timestamp()

Fixes: cb119d535083 ("iio: proximity: add support for PulsedLight LIDAR")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Matt Ranostay <matt.ranostay@konsulko.com>
Acked-by: Matt Ranostay <matt.ranostay@konsulko.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210501170121.512209-14-jic23@kernel.org

diff --git a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
index cc206bf..d854b8d 100644 (file)
--- a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
+++ b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
@@ -44,7 +44,11 @@ struct lidar_data {
        int (*xfer)(struct lidar_data *data, u8 reg, u8 *val, int len);
        int i2c_enabled;
 
-       u16 buffer[8]; /* 2 byte distance + 8 byte timestamp */
+       /* Ensure timestamp is naturally aligned */
+       struct {
+               u16 chan;
+               s64 timestamp __aligned(8);
+       } scan;
 };
 
 static const struct iio_chan_spec lidar_channels[] = {
@@ -230,9 +234,9 @@ static irqreturn_t lidar_trigger_handler(int irq, void *private)
        struct lidar_data *data = iio_priv(indio_dev);
        int ret;
 
-       ret = lidar_get_measurement(data, data->buffer);
+       ret = lidar_get_measurement(data, &data->scan.chan);
        if (!ret) {
-               iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+               iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
                                                   iio_get_time_ns(indio_dev));
        } else if (ret != -EINVAL) {
                dev_err(&data->client->dev, "cannot read LIDAR measurement");