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author | Hans de Goede <hdegoede@redhat.com> | 2015-01-20 09:22:26 +0100 |
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committer | Hans de Goede <hdegoede@redhat.com> | 2015-01-22 20:44:33 +0100 |
commit | a5464f2bd22b46d440bb634eddac3b7cfefe10c0 (patch) | |
tree | 03bdd9586ba6d600feb3ff97d6b6a7b189579752 /drivers/video/hitachi_tx18d42vm_lcd.c | |
parent | 1a800f7af3ef5f42ff703fd4b313b79e471f6ced (diff) | |
download | u-boot-imx-a5464f2bd22b46d440bb634eddac3b7cfefe10c0.zip u-boot-imx-a5464f2bd22b46d440bb634eddac3b7cfefe10c0.tar.gz u-boot-imx-a5464f2bd22b46d440bb634eddac3b7cfefe10c0.tar.bz2 |
video: Add support for Hitachi tx18d42vm LVDS LCD panels
Add support for Hitachi tx18d42vm LVDS LCD panels, these panels have a
lcd controller which needs to be initialized over SPI, once that is
done they work like a regular LVDS panel.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Anatolij Gustschin <agust@denx.de>
Diffstat (limited to 'drivers/video/hitachi_tx18d42vm_lcd.c')
-rw-r--r-- | drivers/video/hitachi_tx18d42vm_lcd.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/video/hitachi_tx18d42vm_lcd.c b/drivers/video/hitachi_tx18d42vm_lcd.c new file mode 100644 index 0000000..1ce4a8c --- /dev/null +++ b/drivers/video/hitachi_tx18d42vm_lcd.c @@ -0,0 +1,81 @@ +/* + * Hitachi tx18d42vm LVDS LCD panel driver + * + * (C) Copyright 2015 Hans de Goede <hdegoede@redhat.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.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; +} |