[PATCH 1/2] iio: light: adux1020: fix interrupt clear value on SMBus-only adapters

[Raffaele Tranfaglia via B4 Relay]

From: Raffaele Tranfaglia <raffaele.tranfaglia@xxxxxxxxx>

adux1020_measure() clears the mode interrupt by writing the inverted
interrupt enable mask to INT_STATUS. The mask is a u16, but integer
promotion makes ~0x00f0 evaluate to 0xffffff0f, which does not fit in
the 16-bit register.

On adapters supporting plain I2C, regmap formats the value with
put_unaligned_be16() and silently truncates it to 0xff0f. On adapters
that only support SMBus word transfers, regmap_smbus_word_write_swapped()
rejects values above 0xffff with -EINVAL, so every proximity read fails.

Mask the value to 16 bits so that SMBus-only adapters send the same
0xff0f that has always been written on plain I2C adapters.

Fixes: 356543545576 ("iio: light: Add support for ADUX1020 sensor")
Signed-off-by: Raffaele Tranfaglia <raffaele.tranfaglia@xxxxxxxxx>
---
 drivers/iio/light/adux1020.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/light/adux1020.c b/drivers/iio/light/adux1020.c
index d4281b9754c3..cccd509dd18a 100644
--- a/drivers/iio/light/adux1020.c
+++ b/drivers/iio/light/adux1020.c
@@ -346,7 +346,7 @@ static int adux1020_measure(struct adux1020_data *data,
 
 	/* Clear mode interrupt */
 	ret = regmap_write(data->regmap, ADUX1020_REG_INT_STATUS,
-			   (~adux1020_modes[mode].int_en));
+			   ~adux1020_modes[mode].int_en & 0xffff);
 	if (ret < 0)
 		return ret;
 

-- 
2.56.0