ASoC: davinci-mcasp: Correct rx format unit configuration

In case of capture we should not use rotation. The reverse and mask is
enough to get the data align correctly from the bus to MCU:
Format	  data from bus    after reverse (XRBUF)
S16_LE:  |LSB|MSB|xxx|xxx|  |xxx|xxx|MSB|LSB|
S24_3LE: |LSB|DAT|MSB|xxx|  |xxx|MSB|DAT|LSB|
S24_LE:  |LSB|DAT|MSB|xxx|  |xxx|MSB|DAT|LSB|
S32_LE:  |LSB|DAT|DAT|MSB|  |MSB|DAT|DAT|LSB|

With this patch all supported formats will work for playback and capture.

Reported-by: Jyri Sarha <jsarha@ti.com> (broken S24_3LE capture)
Signed-off-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

sound/soc/davinci/davinci-mcasp.c

@@ -459,8 +459,17 @@ static int davinci_config_channel_size(struct davinci_mcasp *mcasp,
 {
 	u32 fmt;
 	u32 tx_rotate = (word_length / 4) & 0x7;
-	u32 rx_rotate = (32 - word_length) / 4;
 	u32 mask = (1ULL << word_length) - 1;
+	/*
+	 * For captured data we should not rotate, inversion and masking is
+	 * enoguh to get the data to the right position:
+	 * Format	  data from bus		after reverse (XRBUF)
+	 * S16_LE:	|LSB|MSB|xxx|xxx|	|xxx|xxx|MSB|LSB|
+	 * S24_3LE:	|LSB|DAT|MSB|xxx|	|xxx|MSB|DAT|LSB|
+	 * S24_LE:	|LSB|DAT|MSB|xxx|	|xxx|MSB|DAT|LSB|
+	 * S32_LE:	|LSB|DAT|DAT|MSB|	|MSB|DAT|DAT|LSB|
+	 */
+	u32 rx_rotate = 0;
 
 	/*
 	 * if s BCLK-to-LRCLK ratio has been configured via the set_clkdiv()