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authorLeif Middelschulte <leif.middelschulte@gmail.com>2017-04-23 21:19:58 +0200
committerMark Brown <broonie@kernel.org>2017-04-25 16:37:53 +0100
commitf72efa7e690ab5c4068ccba31c4da032bc45c29c (patch)
tree2ff01c9757a2151e4a5d655889053c854a818cf4 /drivers/spi/spi-imx.c
parentc1ae3cfa0e89fa1a7ecc4c99031f5e9ae99d9201 (diff)
downloadlinux-f72efa7e690ab5c4068ccba31c4da032bc45c29c.tar.bz2
spi-imx: Implements handling of the SPI_READY mode flag.
This patch implements consideration of the SPI_READY mode flag as defined in spi.h. It extends the device tree bindings to support the values defined by the reference manual for the DRCTL field. Thus supporting edge-triggered and level-triggered bursts. Signed-off-by: Leif Middelschulte <Leif.Middelschulte@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-imx.c')
-rw-r--r--drivers/spi/spi-imx.c20
1 files changed, 18 insertions, 2 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 9a7c62f471dc..b402530a7a9a 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -95,6 +95,7 @@ struct spi_imx_data {
unsigned int spi_bus_clk;
unsigned int bytes_per_word;
+ unsigned int spi_drctl;
unsigned int count;
void (*tx)(struct spi_imx_data *);
@@ -246,6 +247,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
#define MX51_ECSPI_CTRL_XCH (1 << 2)
#define MX51_ECSPI_CTRL_SMC (1 << 3)
#define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4)
+#define MX51_ECSPI_CTRL_DRCTL(drctl) ((drctl) << 16)
#define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
#define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
#define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18)
@@ -355,6 +357,12 @@ static int mx51_ecspi_config(struct spi_device *spi,
*/
ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
+ /*
+ * Enable SPI_RDY handling (falling edge/level triggered).
+ */
+ if (spi->mode & SPI_READY)
+ ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
+
/* set clock speed */
ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk);
spi_imx->spi_bus_clk = clk;
@@ -1173,7 +1181,7 @@ static int spi_imx_probe(struct platform_device *pdev)
struct spi_master *master;
struct spi_imx_data *spi_imx;
struct resource *res;
- int i, ret, irq;
+ int i, ret, irq, spi_drctl;
if (!np && !mxc_platform_info) {
dev_err(&pdev->dev, "can't get the platform data\n");
@@ -1181,6 +1189,12 @@ static int spi_imx_probe(struct platform_device *pdev)
}
master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data));
+ ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
+ if ((ret < 0) || (spi_drctl >= 0x3)) {
+ /* '11' is reserved */
+ spi_drctl = 0;
+ }
+
if (!master)
return -ENOMEM;
@@ -1216,7 +1230,9 @@ static int spi_imx_probe(struct platform_device *pdev)
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_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx))
- spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
+ spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
+
+ spi_imx->spi_drctl = spi_drctl;
init_completion(&spi_imx->xfer_done);