[nRF52840] SPI data control pin definition (.dts)

RE: [nRF52840] SPI data control pin definition (.dts)

Håkon Alseth — Fri, 16 Sep 2022 11:52:34 GMT

Hi,

It is hard to test on my end, as you're developing your own driver, and I do not have the build artifacts to look at.

What you can try is to rather address the variable like this and see if this helps?

DT_PROP(DT_NODELABEL(ssd1333), width)

Kind regards,

Håkon

RE: [nRF52840] SPI data control pin definition (.dts)

AnomalySmith — Fri, 16 Sep 2022 08:11:48 GMT

Sure, I've got an overlay file that describes:

/*
* nRF52840_dk      SSD1333 (160x128)
* 
* P0.28 (RESET)   RES
* P0.30 (D5)      DC (DATA/CMD)
* P0.5 (SCK)      SCL
* P1.0 (MOSI)     SDA
* P1.08 (CS)      SDA
*/

/ {
  chosen {
    zephyr,display = &ssd1333;
  };
};

&pinctrl {
 spi3_default: spi3_default {
   group1 {
     psels = <NRF_PSEL(SPIM_SCK, 0, 5)>,
       <NRF_PSEL(SPIM_MOSI, 0, 32)>,
       <NRF_PSEL(SPIM_MISO, 0, 31)>;
   };
 };

 spi3_sleep: spi3_sleep {
   group1 {
     psels = <NRF_PSEL(SPIM_SCK, 0, 5)>,
       <NRF_PSEL(SPIM_MOSI, 0, 32)>,
       <NRF_PSEL(SPIM_MISO, 0, 31)>;
     low-power-enable;
   };
 };
};

&spi3 {
  compatible = "nordic,nrf-spim";
  status = "okay";
  pinctrl-0 = <&spi3_default>;
  pinctrl-1 = <&spi3_sleep>;
  cs-gpios = <&gpio0 25 GPIO_ACTIVE_LOW>;
  pinctrl-names = "default", "sleep";

  ssd1333: ssd1333@0 {
    compatible = "solomon,ssd1333";
    label = "SSD1333";
    spi-max-frequency = <20000000>;
    reg = <0>;
    cmd-data-pin = <&gpio0 30 GPIO_ACTIVE_LOW>;
    reset-pin = < &gpio0 28 GPIO_ACTIVE_LOW >;
    width = <160>;
    height = <128>;
    x-offset = <0>;
    y-offset = <0>;
    vcom = <0x19>;
    gctrl = <0x35>;
  };
};

Otherwise, I don't have any ssd1333-common.yaml file (as I don't see any on displays drivers and samples)

RE: [nRF52840] SPI data control pin definition (.dts)

Håkon Alseth — Fri, 16 Sep 2022 07:55:12 GMT

Have you checked that "width" and "height" is described in your ssd1333-common.yaml file?

Can you share your build-folder/zephyr/zephyr.dts file?

Kind regards,

Håkon

RE: [nRF52840] SPI data control pin definition (.dts)

AnomalySmith — Fri, 16 Sep 2022 06:28:10 GMT

Thanks, applying this logic makes more sense :)

But now, just another error comes up about the custom properties :

In file included from /opt/nordic/ncs/v2.0.2/zephyr/include/zephyr/arch/arm/aarch32/arch.h:20,
                 from /opt/nordic/ncs/v2.0.2/zephyr/include/zephyr/arch/cpu.h:19,
                 from /opt/nordic/ncs/v2.0.2/zephyr/include/zephyr/kernel_includes.h:33,
                 from /opt/nordic/ncs/v2.0.2/zephyr/include/zephyr/kernel.h:17,
                 from /opt/nordic/ncs/v2.0.2/zephyr/include/zephyr/init.h:11,
                 from /opt/nordic/ncs/v2.0.2/zephyr/include/zephyr/device.h:29,
                 from /opt/nordic/ncs/v2.0.2/zephyr/drivers/display/ssd1333.c:13:
/opt/nordic/ncs/v2.0.2/zephyr/drivers/display/ssd1333.c: In function 'ssd1333_get_capabilities':
/opt/nordic/ncs/v2.0.2/zephyr/include/zephyr/devicetree.h:305:40: error: 'DT_N_INST_3_solomon_ssd1333_P_width' undeclared (first use in this function)
  305 | #define DT_INST(inst, compat) UTIL_CAT(DT_N_INST, DT_DASH(inst, compat))
      |

On the related driver's function :

static void ssd1333_get_capabilities(const struct device *dev, struct display_capabilities *caps) {
  memset(caps, 0, sizeof(struct display_capabilities));
  caps->x_resolution = DT_INST_PROP(3, width);
  caps->y_resolution = DT_INST_PROP(3, height);
  caps->supported_pixel_formats = PIXEL_FORMAT_RGB_565;
  caps->current_pixel_format = PIXEL_FORMAT_RGB_565;
  caps->screen_info = 0;
  caps->current_orientation = DISPLAY_ORIENTATION_NORMAL;
}

I'm trying to see any difference between the ssd1306 sample but still can't find any :/

Do you have an idea ? Where should I also define those ?

EDIT: I've changed slightly the driver file to align with the ssd16xx one and the error is gone for now :

caps->x_resolution = config->width; // instead of DT_INST_PROP(0, width);...
caps->y_resolution = config->height;

Still others error but will go into it and let you know the final outcome 🙂

RE: [nRF52840] SPI data control pin definition (.dts)

Håkon Alseth — Thu, 15 Sep 2022 14:11:40 GMT

Hi,

This is your current DT setup:

&spi3 {
  status = "okay";
  device_type = "spi";
  compatible = "nordic,nrf-spim";
  sck-pin = < 5 >;
  mosi-pin = < 32 >;
  data-ctrl-pin = <&gpio0 30 GPIO_ACTIVE_LOW>;
  clock-frequency = <8000000>;
  cs-pin = < &gpio1 8 GPIO_ACTIVE_LOW >;
  reset-pin = < &gpio0 28 GPIO_ACTIVE_LOW >;

  ssd1333: ssd1333@0 {
      compatible = "solomon,ssd1333";
      status = "okay";
      reg = < 0x0 >;
      label = "OLED_DISPLAY";
      spi-max-frequency = < 0x16e3600 >;
      width = <160>;
      height = <128>;
  };

You should move the non-standard SPI properties to your sensor definition, ie:

&spi3 {
  status = "okay";
  compatible = "nordic,nrf-spim";
  ...


  ssd1333: ssd1333@0 {
      compatible = "solomon,ssd1333";
      ...
      reset-pin = < &gpio0 28 GPIO_ACTIVE_LOW >;
      data-ctrl-pin = <&gpio0 30 GPIO_ACTIVE_LOW>;
  };

Similar to how it's done in ssd1306:

https://github.com/nrfconnect/sdk-zephyr/blob/v3.1.99-ncs1-rc1/boards/shields/ssd1306/ssd1306_128x64_spi.overlay#L29-L30

[quote user=""]Also, if I use this spi3 on nRF52840 that way, will I be able to set the max 32MHz clock over SPI (and Easy DMA but I think not)?[/quote]

spi3 is 32M capable, but I would strongly recommend that you test on lower speeds to ensure that your driver works first.

32M speed also has strict requirements wrt. pcb trace length and the GPIOs used needs to be set in high-drive (configured in NRF_Px->PIN_CNF[] register)

Kind regards,

Håkon