Re: [PATCH] spi: imx: add 16/32 bits per word support for slave mode

From: Tomas Melin
Date: Mon May 24 2021 - 04:25:37 EST


Hi,

On 4/8/21 1:33 PM, Clark Wang wrote:
Enable 16/32 bits per word support for spi-imx slave mode.
It only support 8 bits per word in slave mode before.

Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
Reviewed-by: Haibo Chen <haibo.chen@xxxxxxx>
---
drivers/spi/spi-imx.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 4fe767acaca7..24ba7ab1b05d 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -386,7 +386,12 @@ static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
{
- u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
+ u32 val = readl(spi_imx->base + MXC_CSPIRXDATA);
+
+ if (spi_imx->bits_per_word <= 8)
+ val = be32_to_cpu(val);
+ else if (spi_imx->bits_per_word <= 16)
+ val = (val << 16) | (val >> 16);

Would it be good to use available

    spi_imx_buf_rx_u32

    spi_imx_buf_rx_u16

    spi_imx_buf_rx_u8

helpers here?

thanks,

Tomas


if (spi_imx->rx_buf) {
int n_bytes = spi_imx->slave_burst % sizeof(val);
@@ -415,7 +420,11 @@ static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
if (spi_imx->tx_buf) {
memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
spi_imx->tx_buf, n_bytes);
- val = cpu_to_be32(val);
+ if (spi_imx->bits_per_word <= 8)
+ val = cpu_to_be32(val);
+ else if (spi_imx->bits_per_word <= 16)
+ val = (val << 16) | (val >> 16);
+
spi_imx->tx_buf += n_bytes;
}