i.MX ProcessorsのトピックRe: SPI mode not clocking as configured

SPI mode not clocking as configured

mukelarvin — Mon, 02 Nov 2020 13:09:06 GMT

Hi I'm having some trouble with the SPI on my IMX6S based Riotboard. I am running Android v4.3 with kernel v3.0.35.

I'm trying to get SPI_MODE3 to work but it appears to always clock out in SPI_MODE0. Has anyone seen this before?

Spidev test program:

root@RIoTboard_6solo:/ # /system/lcdtest/spidev_test -H -O

spi mode: 3

bits per word: 8

max speed: 500000 Hz (500 KHz)

FF FF FF FF FF FF

FF FF

Output on logic analyser:

Re: SPI mode not clocking as configured

mukelarvin — Thu, 10 Jul 2014 15:10:40 GMT

I found a guy who had the same problem and got SPI_MODE_3 working.

SPI_MODE_3 On I.mx6q, ECSPI2

Re: SPI mode not clocking as configured

mxpencil — Mon, 13 Apr 2015 08:21:46 GMT

Hi, Luke

I had the same problem. Could you share the method you solve it. Thanks!

raohechang@hust.edu.cn

Re: Re: SPI mode not clocking as configured

mukelarvin — Mon, 13 Apr 2015 14:43:59 GMT

Well it looks like they deleted the post that I used as a reference. That's not very helpful.

I think I was able to find the change that I made.

diff --git a/drivers/spi/spi_imx.c b/drivers/spi/spi_imx.c
index be58e17..4bc1b70 100644
--- a/drivers/spi/spi_imx.c
+++ b/drivers/spi/spi_imx.c
@@ -185,6 +185,7 @@ static unsigned int spi_imx_clkdiv_2(unsigned int fin,
#define SPI_IMX2_3_CONFIG_SCLKPOL(cs)  (1 << ((cs) +  4))
#define SPI_IMX2_3_CONFIG_SBBCTRL(cs)  (1 << ((cs) +  8))
#define SPI_IMX2_3_CONFIG_SSBPOL(cs)  (1 << ((cs) + 12))
+#define SPI_IMX2_3_CONFIG_SCLKCTL(cs)    (1 << ((cs) + 20))

#define SPI_IMX2_3_INT        0x10
#define SPI_IMX2_3_INT_TEEN            (1 <<  0)
@@ -276,7 +277,10 @@ static int __maybe_unused spi_imx2_3_config(struct spi_imx_data *spi_imx,
                cfg |= SPI_IMX2_3_CONFIG_SCLKPHA(config->cs);

        if (config->mode & SPI_CPOL)
-              cfg |= SPI_IMX2_3_CONFIG_SCLKPOL(config->cs);
+      {
+              //cfg |= SPI_IMX2_3_CONFIG_SCLKPOL(config->cs);
+              cfg |= SPI_IMX2_3_CONFIG_SCLKCTL(config->cs);
+      }

        if (config->mode & SPI_CS_HIGH)
                cfg |= SPI_IMX2_3_CONFIG_SSBPOL(config->cs);

That may help. Although in the end I ended up bit banging the SPI.

Re: Re: SPI mode not clocking as configured

kaisun1 — Thu, 16 Jul 2015 03:35:51 GMT

Hi Luke,

i have the same problem of the spi_mode changge, but i used your method, i found the spi_imx2_3_config have not used ，Pls，give me suggest.

ken