dma_request_chan() returns error pointer in case of failures, but
the rz_ssi_dma_request() checked for NULL pointer instead.
This patch fixes the issue by checking for ERR_PTR() instead of
NULL and sets the DMA pointers to NULL in error case so that ssi
can fallback to PIO mode.
Fixes: 26ac471c53 ("ASoC: sh: rz-ssi: Add SSI DMAC support")
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20210818101450.15948-1-biju.das.jz@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
4b14f17912