[PATCH v3 2/8] iio: adc: ti-adc128s052: Simplify using be16_to_cpu()

Matti Vaittinen
2025-04-07T11:36:05Z

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The register data is 12-bit big-endian data. Use be16_to_cpu() to do
the conversion, and simple bitwise AND for masking to make it more
obvious.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
---
Revision history:
v2 => v3:
- Decrease amount of changed lines by keeping the old buffer name.
v1 => v2:
- Fix commit msg to reflect the fact there was no bug
- Drop Fixes tag
- Use union for rx / tx buffer to avoid casting
- Keep the shared message protected by the mutex
---
drivers/iio/adc/ti-adc128s052.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/adc/ti-adc128s052.c b/drivers/iio/adc/ti-adc128s052.c
index a456ea78462f..c5b2374322e4 100644
--- a/drivers/iio/adc/ti-adc128s052.c
+++ b/drivers/iio/adc/ti-adc128s052.c
@@ -28,7 +28,10 @@ struct adc128 {
struct regulator *reg;
struct mutex lock;

- u8 buffer[2] __aligned(IIO_DMA_MINALIGN);
+ union {
+ __be16 buffer16;
+ u8 buffer[2];
+ } __aligned(IIO_DMA_MINALIGN);
};

static int adc128_adc_conversion(struct adc128 *adc, u8 channel)
@@ -40,20 +43,18 @@ static int adc128_adc_conversion(struct adc128 *adc, u8 channel)
adc->buffer[0] = channel << 3;
adc->buffer[1] = 0;

- ret = spi_write(adc->spi, &adc->buffer, 2);
+ ret = spi_write(adc->spi, &adc->buffer, sizeof(adc->buffer));
if (ret < 0) {
mutex_unlock(&adc->lock);
return ret;
}

- ret = spi_read(adc->spi, &adc->buffer, 2);
-
+ ret = spi_read(adc->spi, &adc->buffer16, sizeof(adc->buffer16));
mutex_unlock(&adc->lock);
-
if (ret < 0)
return ret;

- return ((adc->buffer[0] << 8 | adc->buffer[1]) & 0xFFF);
+ return be16_to_cpu(adc->buffer16) & 0xFFF;
}

static int adc128_read_raw(struct iio_dev *indio_dev,