[PATCH v6 1/8] spi: imx: fix loopback mode setup after controller reset

[Anton Bondarenko]

If controller hold in reset it's not possible to write any
register except CTRL. So all other registers must be updated
only after controller bring out from reset.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@xxxxxxxxx>
---
 drivers/spi/spi-imx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 410522f..3aa33c8 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -356,6 +356,9 @@ static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
 	else
 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(config->cs);
 
+	/* CTRL register always go first to bring out controller from reset */
+	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
+
 	reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 	if (config->mode & SPI_LOOP)
 		reg |= MX51_ECSPI_TESTREG_LBC;
@@ -363,7 +366,6 @@ static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
 		reg &= ~MX51_ECSPI_TESTREG_LBC;
 	writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
 
-	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 
 	/*
-- 
2.6.3

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