From: Fabio Estevam <[email protected]> Loopback mode can be activated by setting bit LBC (LoopBack Control) of register ECSPI_TESTREG.
Add support for it. Signed-off-by: Fabio Estevam <[email protected]> --- drivers/spi/spi-imx.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 0e5723a..e7e4f0c 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -244,6 +244,9 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, #define MX51_ECSPI_STAT 0x18 #define MX51_ECSPI_STAT_RR (1 << 3) +#define MX51_ECSPI_TESTREG 0x20 +#define MX51_ECSPI_TESTREG_LBC BIT(31) + /* MX51 eCSPI */ static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi, unsigned int *fres) @@ -313,7 +316,7 @@ static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, { u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0, dma = 0; u32 tx_wml_cfg, rx_wml_cfg, rxt_wml_cfg; - u32 clk = config->speed_hz, delay; + u32 clk = config->speed_hz, delay, reg; /* * The hardware seems to have a race condition when changing modes. The @@ -351,6 +354,13 @@ static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, else cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(config->cs); + reg = readl(spi_imx->base + MX51_ECSPI_TESTREG); + if (config->mode & SPI_LOOP) + reg |= MX51_ECSPI_TESTREG_LBC; + else + 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); @@ -1141,7 +1151,8 @@ static int spi_imx_probe(struct platform_device *pdev) spi_imx->bitbang.master->cleanup = spi_imx_cleanup; 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; + spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | + SPI_LOOP; init_completion(&spi_imx->xfer_done); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
