Error -12 (Out of memory) when using a SPI device

Hello
I'm trying to use a display ST7735 in an A133 processor from Allwinner (sun50iw10p1), but the device is not being loaded during Kernel boot, I'm getting the error message "probe of spi2.0 failed with error -12".
After some research, I discovered that this error happens when there is a lack of memory, but which kind of memory? I tried different things in the device tree, tried different things in the kernel configuration file, but nothing changes.
It cannot lack RAM or flash, the full memory configuration that I'm using is 2GB RAM and 16GB of flash memory.
What can I try to overcome this error message?

In the kernel configuration file, I have:
CONFIG_SPI=y
CONFIG_SPI_SUNXI=y
CONFIG_SPI_SPIDEV=y

In the default configuration file, I have:
spi2: spi@05012000 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "allwinner,sun50i-spi";
device_type = "spi2";
reg = <0x0 0x05012000 0x0 0x1000>;
interrupts = <GIC_SPI 15 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clk_pll_periph0>, <&clk_spi2>;
clock-frequency = <100000000>;
pinctrl-names = "default", "sleep";
pinctrl-0 = <&spi2_pins_a &spi2_pins_b>;
pinctrl-1 = <&spi2_pins_c>;
spi2_cs_number = <1>;
spi2_cs_bitmap = <1>;
status = "disabled";
};

In the board configuration file (overlay), I have:
spi2_pins_a: spi2@0 {
allwinner,pins = "PB1", "PB2", "PB3";
allwinner,pname = "spi2_sclk", "spi2_mosi",
"spi2_miso";
allwinner,function = "spi2";
allwinner,muxsel = <3>;
allwinner,drive = <1>;
allwinner,pull = <0>;
};

spi2_pins_b: spi2@1 {
allwinner,pins = "PB0";
allwinner,pname = "spi2_cs0";
allwinner,function = "spi2";
allwinner,muxsel = <3>;
allwinner,drive = <1>;
allwinner,pull = <1>; /* only CS should be pulled up */
};

spi2_pins_c: spi2@2 {
allwinner,pins = "PB0", "PB1", "PB2", "PB3";
allwinner,function = "io_disabled";
allwinner,muxsel = <7>;
allwinner,drive = <1>;
allwinner,pull = <0>;
};

spi2: spi@05012000 {
pinctrl-0 = <&spi2_pins_a &spi2_pins_b>;
pinctrl-1 = <&spi2_pins_c>;
spi_slave_mode = <0>;
status = "okay";

st7735r0: st7735r@0 {
compatible = "sitronix,st7735r";
reg = <0>;
pinctrl-names = "default";
spi-max-frequency = <32000000>;
rotate = <90>;
bgr;
fps = <20>;
height=<130>;
width=<130>;
buswidth = <8>;
reset-gpios = <&pio PE 9 1 0 1 0>;
dc-gpios = <&pio PE 8 1 0 1 0>;
};
};

Hi,
at first would be nice to use code tags, that will make your post more readable.

Originally Posted by eric976 Hello I'm trying to use a display ST7735 in an A133 processor from Allwinner (sun50iw10p1), but the device is not being loaded during Kernel boot, I'm getting the error message "probe of spi2.0 failed with error -12".

Probably it is already loaded?

Originally Posted by eric976 After some research, I discovered that this error happens when there is a lack of memory, but which kind of memory?

This is the main memory, the RAM.

Originally Posted by eric976 I tried different things in the device tree, tried different things in the kernel configuration file, but nothing changes. It cannot lack RAM or flash, the full memory configuration that I'm using is 2GB RAM and 16GB of flash memory. What can I try to overcome this error message?

Yes, 2 GB should be enough, but I think it needs some dedicated area which is already occupied.

Originally Posted by pan64 Hi, at first would be nice to use code tags, that will make your post more readable. Probably it is already loaded? This is the main memory, the RAM. Yes, 2 GB should be enough, but I think it needs some dedicated area which is already occupied.

Thanks for your answer... Just some updates...
Update: I was debugging what was happening inside the functions located in the file fbtft-core.c and I saw that the issue is related to the DMA.

If I replace this

if (txbuflen > 0) {
#ifdef CONFIG_HAS_DMA
		if (dma) {
			dev->coherent_dma_mask = ~0;
			txbuf = dmam_alloc_coherent(dev, txbuflen, &par->txbuf.dma, GFP_DMA);
		} else
#endif
		{
			txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
		}
		if (!txbuf)
			goto alloc_fail;
		par->txbuf.buf = txbuf;
		par->txbuf.len = txbuflen;
	}

To only this:

if (txbuflen > 0) {
			txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
		if (!txbuf)
			goto alloc_fail;
		par->txbuf.buf = txbuf;
		par->txbuf.len = txbuflen;
	}

There is no error message, but it is still not working... =/