[PATCH 2/3] fpga manager: xilinx-spi: provide better diagnostics on programming failure

[Luca Ceresoli]

When the DONE pin does not go high after programming to confirm programming
success, the INIT_B pin provides some info on the reason. Use it if
available to provide a more explanatory error message.

Signed-off-by: Luca Ceresoli <luca@xxxxxxxxxxxxxxxx>
---
 drivers/fpga/xilinx-spi.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/fpga/xilinx-spi.c b/drivers/fpga/xilinx-spi.c
index 502fae0d1d85..2aa942bb1114 100644
--- a/drivers/fpga/xilinx-spi.c
+++ b/drivers/fpga/xilinx-spi.c
@@ -169,7 +169,16 @@ static int xilinx_spi_write_complete(struct fpga_manager *mgr,
 			return xilinx_spi_apply_cclk_cycles(conf);
 	}
 
-	dev_err(&mgr->dev, "Timeout after config data transfer.\n");
+	if (conf->init_b) {
+		int init_b_asserted = gpiod_get_value(conf->init_b);
+
+		dev_err(&mgr->dev,
+			init_b_asserted ? "CRC error or invalid device\n"
+			: "Missing sync word or incomplete bitstream\n");
+	} else {
+		dev_err(&mgr->dev, "Timeout after config data transfer.\n");
+	}
+
 	return -ETIMEDOUT;
 }
 
-- 
2.28.0