In some cases the NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD interrupt flag is not set along with NWL_DSI_RX_PKT_HDR_RCVD when the initial interrupt fires. Since the NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD_MASK was not set then the ISR does not fire again when NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD is finally set and the read times out. Also the read packet handling checks for NWL_DSI_DPHY_DIRECTION which is not always set when the ISR for reading the payload runs. Instead it seems better to check xfer->direction is DSI_PACKET_RECEIVE (more similar to the send packet case). The above two changes were required to perform a successful DCS read from a display with a Chipone ICNL9707 driver IC. Signed-off-by: Kevin Groeneveld <kgroeneveld@xxxxxxxxxxxx> --- drivers/gpu/drm/bridge/nwl-dsi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c index 6dc2a4e191d7..241568a17f60 100644 --- a/drivers/gpu/drm/bridge/nwl-dsi.c +++ b/drivers/gpu/drm/bridge/nwl-dsi.c @@ -334,6 +334,7 @@ static int nwl_dsi_init_interrupts(struct nwl_dsi *dsi) { u32 irq_enable = ~(u32)(NWL_DSI_TX_PKT_DONE_MASK | NWL_DSI_RX_PKT_HDR_RCVD_MASK | + NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD_MASK | NWL_DSI_TX_FIFO_OVFLW_MASK | NWL_DSI_HS_TX_TIMEOUT_MASK); @@ -489,7 +490,7 @@ static void nwl_dsi_finish_transmission(struct nwl_dsi *dsi, u32 status) status & NWL_DSI_TX_PKT_DONE) { xfer->status = xfer->tx_len; end_packet = true; - } else if (status & NWL_DSI_DPHY_DIRECTION && + } else if (xfer->direction == DSI_PACKET_RECEIVE && ((status & (NWL_DSI_RX_PKT_HDR_RCVD | NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD)))) { end_packet = nwl_dsi_read_packet(dsi, status); -- 2.34.1