diff options
Diffstat (limited to 'roms/u-boot/drivers/video/hitachi_tx18d42vm_lcd.c')
-rw-r--r-- | roms/u-boot/drivers/video/hitachi_tx18d42vm_lcd.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/video/hitachi_tx18d42vm_lcd.c b/roms/u-boot/drivers/video/hitachi_tx18d42vm_lcd.c new file mode 100644 index 000000000..c6c8df6a9 --- /dev/null +++ b/roms/u-boot/drivers/video/hitachi_tx18d42vm_lcd.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Hitachi tx18d42vm LVDS LCD panel driver + * + * (C) Copyright 2015 Hans de Goede <hdegoede@redhat.com> + */ + +#include <common.h> +#include <malloc.h> +#include <linux/delay.h> + +#include <asm/gpio.h> +#include <errno.h> + +/* + * Very simple write only SPI support, this does not use the generic SPI infra + * because that assumes R/W SPI, requiring a MISO pin. Also the necessary glue + * code alone would be larger then this minimal version. + */ +static void lcd_panel_spi_write(int cs, int clk, int mosi, + unsigned int data, int bits) +{ + int i, offset; + + gpio_direction_output(cs, 0); + for (i = 0; i < bits; i++) { + gpio_direction_output(clk, 0); + offset = (bits - 1) - i; + gpio_direction_output(mosi, (data >> offset) & 1); + udelay(2); + gpio_direction_output(clk, 1); + udelay(2); + } + gpio_direction_output(cs, 1); + udelay(2); +} + +int hitachi_tx18d42vm_init(void) +{ + const u16 init_data[] = { + 0x0029, /* reset */ + 0x0025, /* standby */ + 0x0840, /* enable normally black */ + 0x0430, /* enable FRC/dither */ + 0x385f, /* enter test mode(1) */ + 0x3ca4, /* enter test mode(2) */ + 0x3409, /* enable SDRRS, enlarge OE width */ + 0x4041, /* adopt 2 line / 1 dot */ + }; + int i, cs, clk, mosi, ret = 0; + + cs = name_to_gpio(CONFIG_VIDEO_LCD_SPI_CS); + clk = name_to_gpio(CONFIG_VIDEO_LCD_SPI_SCLK); + mosi = name_to_gpio(CONFIG_VIDEO_LCD_SPI_MOSI); + + if (cs == -1 || clk == -1 || mosi == 1) { + printf("Error tx18d42vm spi gpio config is invalid\n"); + return -EINVAL; + } + + if (gpio_request(cs, "tx18d42vm-spi-cs") != 0 || + gpio_request(clk, "tx18d42vm-spi-clk") != 0 || + gpio_request(mosi, "tx18d42vm-spi-mosi") != 0) { + printf("Error cannot request tx18d42vm spi gpios\n"); + ret = -EBUSY; + goto out; + } + + for (i = 0; i < ARRAY_SIZE(init_data); i++) + lcd_panel_spi_write(cs, clk, mosi, init_data[i], 16); + + mdelay(50); /* All the tx18d42vm drivers have a delay here ? */ + + lcd_panel_spi_write(cs, clk, mosi, 0x00ad, 16); /* display on */ + +out: + gpio_free(mosi); + gpio_free(clk); + gpio_free(cs); + + return ret; +} |