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authorMartin Kaiser <martin@kaiser.cx>2016-09-01 23:39:58 +0300
committerMark Brown <broonie@kernel.org>2016-09-14 20:06:16 +0300
commit15ca92156e6242060dff91c8d8e7fe7ae82d424a (patch)
tree7a0685a057b2d135115fc03afcfc64a70e547b7d
parent2636ba8fa39915c7b8d73166961ebbb4c14251cd (diff)
downloadlinux-15ca92156e6242060dff91c8d8e7fe7ae82d424a.tar.xz
spi: imx: support loopback mode on imx35
imx35 and compatible chipsets support loopback mode by setting a loopback control bit in the test register. Make this setting available for data transfers, similar to what we do for imx51. Signed-off-by: Martin Kaiser <martin@kaiser.cx> Signed-off-by: Mark Brown <broonie@kernel.org>
-rw-r--r--drivers/spi/spi-imx.c12
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 5cc72be30744..53e7a326c213 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -455,6 +455,9 @@ static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
#define MX31_CSPISTATUS 0x14
#define MX31_STATUS_RR (1 << 3)
+#define MX31_CSPI_TESTREG 0x1C
+#define MX31_TEST_LBC (1 << 14)
+
/* These functions also work for the i.MX35, but be aware that
* the i.MX35 has a slightly different register layout for bits
* we do not use here.
@@ -510,6 +513,13 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config)
writel(reg, spi_imx->base + MXC_CSPICTRL);
+ reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
+ if (spi->mode & SPI_LOOP)
+ reg |= MX31_TEST_LBC;
+ else
+ reg &= ~MX31_TEST_LBC;
+ writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
+
return 0;
}
@@ -1186,7 +1196,7 @@ static int spi_imx_probe(struct platform_device *pdev)
spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
- if (is_imx51_ecspi(spi_imx))
+ if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx))
spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
init_completion(&spi_imx->xfer_done);