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-rw-r--r--Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt12
-rw-r--r--Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt8
-rw-r--r--drivers/spi/spi-fsl-dspi.c64
-rw-r--r--drivers/spi/spi-imx.c4
-rw-r--r--drivers/spi/spi-mpc512x-psc.c2
-rw-r--r--drivers/spi/spi-octeon.c2
-rw-r--r--drivers/spi/spi-st-ssc4.c2
7 files changed, 84 insertions, 10 deletions
diff --git a/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt b/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt
index aad527b..523341a 100644
--- a/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt
+++ b/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt
@@ -2,11 +2,21 @@
(CSPI/eCSPI) for i.MX
Required properties:
-- compatible : Should be "fsl,<soc>-cspi" or "fsl,<soc>-ecspi"
+- compatible :
+ - "fsl,imx1-cspi" for SPI compatible with the one integrated on i.MX1
+ - "fsl,imx21-cspi" for SPI compatible with the one integrated on i.MX21
+ - "fsl,imx27-cspi" for SPI compatible with the one integrated on i.MX27
+ - "fsl,imx31-cspi" for SPI compatible with the one integrated on i.MX31
+ - "fsl,imx35-cspi" for SPI compatible with the one integrated on i.MX35
+ - "fsl,imx51-ecspi" for SPI compatible with the one integrated on i.MX51
- reg : Offset and length of the register set for the device
- interrupts : Should contain CSPI/eCSPI interrupt
- fsl,spi-num-chipselects : Contains the number of the chipselect
- cs-gpios : Specifies the gpio pins to be used for chipselects.
+- clocks : Clock specifiers for both ipg and per clocks.
+- clock-names : Clock names should include both "ipg" and "per"
+See the clock consumer binding,
+ Documentation/devicetree/bindings/clock/clock-bindings.txt
- dmas: DMA specifiers for tx and rx dma. See the DMA client binding,
Documentation/devicetree/bindings/dma/dma.txt
- dma-names: DMA request names should include "tx" and "rx" if present.
diff --git a/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt b/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt
index cbbe16e..70af78a 100644
--- a/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt
+++ b/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt
@@ -16,6 +16,12 @@ Optional property:
in big endian mode, otherwise in native mode(same with CPU), for more
detail please see: Documentation/devicetree/bindings/regmap/regmap.txt.
+Optional SPI slave node properties:
+- fsl,spi-cs-sck-delay: a delay in nanoseconds between activating chip
+ select and the start of clock signal, at the start of a transfer.
+- fsl,spi-sck-cs-delay: a delay in nanoseconds between stopping the clock
+ signal and deactivating chip select, at the end of a transfer.
+
Example:
dspi0@4002c000 {
@@ -43,6 +49,8 @@ dspi0@4002c000 {
reg = <0>;
linux,modalias = "m25p80";
modal = "at26df081a";
+ fsl,spi-cs-sck-delay = <100>;
+ fsl,spi-sck-cs-delay = <50>;
};
};
diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index 8213358..5fe54cd 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/drivers/spi/spi-fsl-dspi.c
@@ -20,6 +20,7 @@
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
+#include <linux/math64.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
@@ -29,6 +30,7 @@
#include <linux/sched.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
+#include <linux/time.h>
#define DRIVER_NAME "fsl-dspi"
@@ -51,7 +53,7 @@
#define SPI_CTAR_CPOL(x) ((x) << 26)
#define SPI_CTAR_CPHA(x) ((x) << 25)
#define SPI_CTAR_LSBFE(x) ((x) << 24)
-#define SPI_CTAR_PCSSCR(x) (((x) & 0x00000003) << 22)
+#define SPI_CTAR_PCSSCK(x) (((x) & 0x00000003) << 22)
#define SPI_CTAR_PASC(x) (((x) & 0x00000003) << 20)
#define SPI_CTAR_PDT(x) (((x) & 0x00000003) << 18)
#define SPI_CTAR_PBR(x) (((x) & 0x00000003) << 16)
@@ -59,6 +61,7 @@
#define SPI_CTAR_ASC(x) (((x) & 0x0000000f) << 8)
#define SPI_CTAR_DT(x) (((x) & 0x0000000f) << 4)
#define SPI_CTAR_BR(x) ((x) & 0x0000000f)
+#define SPI_CTAR_SCALE_BITS 0xf
#define SPI_CTAR0_SLAVE 0x0c
@@ -176,6 +179,40 @@ static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
}
}
+static void ns_delay_scale(char *psc, char *sc, int delay_ns,
+ unsigned long clkrate)
+{
+ int pscale_tbl[4] = {1, 3, 5, 7};
+ int scale_needed, scale, minscale = INT_MAX;
+ int i, j;
+ u32 remainder;
+
+ scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
+ &remainder);
+ if (remainder)
+ scale_needed++;
+
+ for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
+ for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
+ scale = pscale_tbl[i] * (2 << j);
+ if (scale >= scale_needed) {
+ if (scale < minscale) {
+ minscale = scale;
+ *psc = i;
+ *sc = j;
+ }
+ break;
+ }
+ }
+
+ if (minscale == INT_MAX) {
+ pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
+ delay_ns, clkrate);
+ *psc = ARRAY_SIZE(pscale_tbl) - 1;
+ *sc = SPI_CTAR_SCALE_BITS;
+ }
+}
+
static int dspi_transfer_write(struct fsl_dspi *dspi)
{
int tx_count = 0;
@@ -354,7 +391,10 @@ static int dspi_setup(struct spi_device *spi)
{
struct chip_data *chip;
struct fsl_dspi *dspi = spi_master_get_devdata(spi->master);
- unsigned char br = 0, pbr = 0, fmsz = 0;
+ u32 cs_sck_delay = 0, sck_cs_delay = 0;
+ unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
+ unsigned char pasc = 0, asc = 0, fmsz = 0;
+ unsigned long clkrate;
if ((spi->bits_per_word >= 4) && (spi->bits_per_word <= 16)) {
fmsz = spi->bits_per_word - 1;
@@ -371,18 +411,34 @@ static int dspi_setup(struct spi_device *spi)
return -ENOMEM;
}
+ of_property_read_u32(spi->dev.of_node, "fsl,spi-cs-sck-delay",
+ &cs_sck_delay);
+
+ of_property_read_u32(spi->dev.of_node, "fsl,spi-sck-cs-delay",
+ &sck_cs_delay);
+
chip->mcr_val = SPI_MCR_MASTER | SPI_MCR_PCSIS |
SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF;
chip->void_write_data = 0;
- hz_to_spi_baud(&pbr, &br,
- spi->max_speed_hz, clk_get_rate(dspi->clk));
+ clkrate = clk_get_rate(dspi->clk);
+ hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate);
+
+ /* Set PCS to SCK delay scale values */
+ ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
+
+ /* Set After SCK delay scale values */
+ ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
chip->ctar_val = SPI_CTAR_FMSZ(fmsz)
| SPI_CTAR_CPOL(spi->mode & SPI_CPOL ? 1 : 0)
| SPI_CTAR_CPHA(spi->mode & SPI_CPHA ? 1 : 0)
| SPI_CTAR_LSBFE(spi->mode & SPI_LSB_FIRST ? 1 : 0)
+ | SPI_CTAR_PCSSCK(pcssck)
+ | SPI_CTAR_CSSCK(cssck)
+ | SPI_CTAR_PASC(pasc)
+ | SPI_CTAR_ASC(asc)
| SPI_CTAR_PBR(pbr)
| SPI_CTAR_BR(br);
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index aea3a67..f08e812 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -903,7 +903,7 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
if (tx) {
desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
- tx->sgl, tx->nents, DMA_TO_DEVICE,
+ tx->sgl, tx->nents, DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx)
goto no_dma;
@@ -915,7 +915,7 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
if (rx) {
desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
- rx->sgl, rx->nents, DMA_FROM_DEVICE,
+ rx->sgl, rx->nents, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx)
goto no_dma;
diff --git a/drivers/spi/spi-mpc512x-psc.c b/drivers/spi/spi-mpc512x-psc.c
index ecae0d4..965d2bd 100644
--- a/drivers/spi/spi-mpc512x-psc.c
+++ b/drivers/spi/spi-mpc512x-psc.c
@@ -588,7 +588,7 @@ static int mpc512x_psc_spi_of_remove(struct platform_device *op)
return mpc512x_psc_spi_do_remove(&op->dev);
}
-static struct of_device_id mpc512x_psc_spi_of_match[] = {
+static const struct of_device_id mpc512x_psc_spi_of_match[] = {
{ .compatible = "fsl,mpc5121-psc-spi", },
{},
};
diff --git a/drivers/spi/spi-octeon.c b/drivers/spi/spi-octeon.c
index b283d53..e99d6a9 100644
--- a/drivers/spi/spi-octeon.c
+++ b/drivers/spi/spi-octeon.c
@@ -238,7 +238,7 @@ static int octeon_spi_remove(struct platform_device *pdev)
return 0;
}
-static struct of_device_id octeon_spi_match[] = {
+static const struct of_device_id octeon_spi_match[] = {
{ .compatible = "cavium,octeon-3010-spi", },
{},
};
diff --git a/drivers/spi/spi-st-ssc4.c b/drivers/spi/spi-st-ssc4.c
index 2faeaa7..f17c0ab 100644
--- a/drivers/spi/spi-st-ssc4.c
+++ b/drivers/spi/spi-st-ssc4.c
@@ -482,7 +482,7 @@ static const struct dev_pm_ops spi_st_pm = {
SET_RUNTIME_PM_OPS(spi_st_runtime_suspend, spi_st_runtime_resume, NULL)
};
-static struct of_device_id stm_spi_match[] = {
+static const struct of_device_id stm_spi_match[] = {
{ .compatible = "st,comms-ssc4-spi", },
{},
};
generated by cgit v0.10.2 at 2024-10-16 00:58:30 (GMT)