[PATCH v2 2/2] ALSA: hda: Transfer firmware in two chunks

[Cezary Rojewski <cezary.rojewski@intel.com>]

As per specification, SDxLVI shall be at least 1 i.e.: two chunks to
perform a valid transfer. This is true for the PCM transfer code but
not firmware-transfer one.

Technical background:
- the LVI > 0 rule shall be obeyed in PCM transfer
- HW permits LVI == 0 when transfer is SW-controlled (SPIB)
- FW download is not a PCM transfer and is SW-controlled (SPIB)

The above is the fundament which AudioDSP firmware loading functions
have been built upon and worked since 2016. The presented changes are to
align the loading flows and avoid rising more questions in the future.

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
---
 sound/hda/hdac_stream.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sound/hda/hdac_stream.c b/sound/hda/hdac_stream.c
index 2670792f43b4..18d74a28a246 100644
--- a/sound/hda/hdac_stream.c
+++ b/sound/hda/hdac_stream.c
@@ -455,6 +455,7 @@ static int setup_bdle(struct hdac_bus *bus,
 		      struct hdac_stream *azx_dev, __le32 **bdlp,
 		      int ofs, int size, int with_ioc)
 {
+	u32 bdle_size = size / 2;
 	__le32 *bdl = *bdlp;
 
 	while (size > 0) {
@@ -469,7 +470,7 @@ static int setup_bdle(struct hdac_bus *bus,
 		bdl[0] = cpu_to_le32((u32)addr);
 		bdl[1] = cpu_to_le32(upper_32_bits(addr));
 		/* program the size field of the BDL entry */
-		chunk = snd_sgbuf_get_chunk_size(dmab, ofs, size);
+		chunk = snd_sgbuf_get_chunk_size(dmab, ofs, bdle_size);
 		/* one BDLE cannot cross 4K boundary on CTHDA chips */
 		if (bus->align_bdle_4k) {
 			u32 remain = 0x1000 - (ofs & 0xfff);
-- 
2.25.1