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>
This commit is contained in:
Martin Kaiser 2016-09-01 22:39:58 +02:00 committed by Mark Brown
parent 2636ba8fa3
commit 15ca92156e

View file

@ -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);