[PATCH v1 6/8] spi: dw: Add mem_ops

Sean Anderson
2020-03-06T21:20:14Z

On 3/6/20 12:03 PM, Eugeniy Paltsev wrote:
> Hi Sean,
>
> I've tested the SPI (with SPI flash) on HSDK board (which have DW SPI) with your changes.
> It completely break SPI on HSDK:
>
> --------------------->8--------------------------
> # sf probe
> unrecognized JEDEC id bytes: ff, ff, ff
> Failed to initialize SPI flash at 0:0 (error -2)
> --------------------->8--------------------------
>
> Tested from maix_spi HEAD (e338571bf528f58b3ced7fbd0c1f5d923caa1cfd)
>
> ---
> Eugeniy Paltsev

Actually, it just occured to me that I did not add support for a gpio cs
to the xfer function, so it's likely that the chip is not enabling the
cs. Can you try testing with the following patch

---
drivers/spi/designware_spi.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c
index 298d1dbab5..a4e3dbd948 100644
--- a/drivers/spi/designware_spi.c
+++ b/drivers/spi/designware_spi.c
@@ -517,6 +517,8 @@ static int dw_spi_exec_op(struct spi_slave *slave, const struct spi_mem_op *op)
if (op->dummy.nbytes)
memset(op_buf + pos, 0xff, op->dummy.nbytes);

+ external_cs_manage(dev, false);
+
priv->tx = &op_buf;
priv->tx_end = priv->tx + op_len;
priv->rx = NULL;
@@ -586,6 +588,8 @@ static int dw_spi_exec_op(struct spi_slave *slave, const struct spi_mem_op *op)
}

dw_write(priv, DW_SPI_SER, 0);
+ external_cs_manage(dev, true);
+
debug("%s: %u bytes xfered\n", __func__, op->data.nbytes);
return ret;
}
--
2.25.0