[PATCH 3.2 041/110] iio: DAC: ad5624r_spi: fix bit shift of output data value

[Ben Hutchings]

3.2.71-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: JM Friedt <jmfriedt@xxxxxxxxxxx>

commit adfa969850ae93beca57f7527f0e4dc10cbe1309 upstream.

The value sent on the SPI bus is shifted by an erroneous number of bits.
The shift value was already computed in the iio_chan_spec structure and
hence subtracting this argument to 16 yields an erroneous data position
in the SPI stream.

Signed-off-by: JM Friedt <jmfriedt@xxxxxxxxxxx>
Acked-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxxx>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/staging/iio/dac/ad5624r_spi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/staging/iio/dac/ad5624r_spi.c
+++ b/drivers/staging/iio/dac/ad5624r_spi.c
@@ -49,7 +49,7 @@ static const struct ad5624r_chip_info ad
 };
 
 static int ad5624r_spi_write(struct spi_device *spi,
-			     u8 cmd, u8 addr, u16 val, u8 len)
+			     u8 cmd, u8 addr, u16 val, u8 shift)
 {
 	u32 data;
 	u8 msg[3];
@@ -62,7 +62,7 @@ static int ad5624r_spi_write(struct spi_
 	 * 14-, 12-bit input code followed by 0, 2, or 4 don't care bits,
 	 * for the AD5664R, AD5644R, and AD5624R, respectively.
 	 */
-	data = (0 << 22) | (cmd << 19) | (addr << 16) | (val << (16 - len));
+	data = (0 << 22) | (cmd << 19) | (addr << 16) | (val << shift);
 	msg[0] = data >> 16;
 	msg[1] = data >> 8;
 	msg[2] = data;

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