waman.prabhu
New member
Hello:
I'm using a custom AM3354 board. We have to make this work on 3.2.0 kernel only.
LINUX ...... 3.2.0 #71 PREEMPT THU APR 13 07:34:59 CEST 2017 ARMV7L GNU/LINUX
We are integrating KD024FM-1B (2.4" LCD) LCD which uses ST7789V IC. We have received the LCD initialization code for 3-wire SPI from the LCD manufacturer.
The below is the snippet in my board file;
View attachment 2098
Based on code from https://github.com/ohporter/linux-am33x/tree/st7735fb ; I've modified the init script as per ST7789
After including the driver code; there was a problem with register_framebuffer which was resolved by patching/modifying the following;
1. make st7735 DMA safe, and
2. fbmem.c
I'm not able to get the timing right. Please suggest.
NOTE: we were able to make the ST7775 functional with the similar approach.
Regards,
Waman Prabhu
I'm using a custom AM3354 board. We have to make this work on 3.2.0 kernel only.
LINUX ...... 3.2.0 #71 PREEMPT THU APR 13 07:34:59 CEST 2017 ARMV7L GNU/LINUX
We are integrating KD024FM-1B (2.4" LCD) LCD which uses ST7789V IC. We have received the LCD initialization code for 3-wire SPI from the LCD manufacturer.
The below is the snippet in my board file;
Code:
#include video/st7789fb.h
static struct pinmux_config spi_pin_mux[] = {
{"mcasp0_aclkx.spi1_sclk", OMAP_MUX_MODE3 | AM33XX_PULL_ENBL | AM33XX_INPUT_EN},
{"mcasp0_axr0.spi1_d1", OMAP_MUX_MODE3 | AM33XX_PULL_ENBL | AM33XX_INPUT_EN},
{"mcasp0_ahclkr.spi1_cs0", OMAP_MUX_MODE3 | AM33XX_PULL_ENBL | AM33XX_PULL_UP | AM33XX_INPUT_EN},
{NULL, 0},
};
/* LCD Controller */
static const struct st7789fb_platform_data lcd_st7789fb_data = {
.rst_gpio = GPIO_TO_PIN(3, 8),
.dc_gpio = GPIO_TO_PIN(0, 7),
};
static struct spi_board_info lcd_spi1_slave_info[] = {
{
.modalias = "st7789fb",
.platform_data = &lcd_st7789fb_data,
.irq = -1,
.max_speed_hz = 3000000, // the timing is the problem at the moment, tried upto 32MHz
.bus_num = 2,
.chip_select = 0,
.mode = SPI_MODE_0,
},
};
/* setup lcd spi1 */
static void __init spi_init(void)
{
setup_pin_mux(spi_pin_mux);
spi_register_board_info(lcd_spi1_slave_info, ARRAY_SIZE(lcd_spi1_slave_info));
}
Based on code from https://github.com/ohporter/linux-am33x/tree/st7735fb ; I've modified the init script as per ST7789
After including the driver code; there was a problem with register_framebuffer which was resolved by patching/modifying the following;
1. make st7735 DMA safe, and
2. fbmem.c
I'm not able to get the timing right. Please suggest.
NOTE: we were able to make the ST7775 functional with the similar approach.
Regards,
Waman Prabhu
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Last edited: