[U-Boot] [PATCH v2 1/2] video: Add support for Hitachi tx18d42vm LVDS LCD panels
Hans de Goede
hdegoede at redhat.com
Tue Jan 20 15:08:01 CET 2015
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 at redhat.com>
---
drivers/video/Kconfig | 15 +++++--
drivers/video/Makefile | 1 +
drivers/video/hitachi_tx18d42vm_lcd.c | 81 +++++++++++++++++++++++++++++++++++
drivers/video/hitachi_tx18d42vm_lcd.h | 9 ++++
4 files changed, 103 insertions(+), 3 deletions(-)
create mode 100644 drivers/video/hitachi_tx18d42vm_lcd.c
create mode 100644 drivers/video/hitachi_tx18d42vm_lcd.h
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index d9d4afc..ccbd7e2 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -36,9 +36,18 @@ config VIDEO_LCD_SSD2828_RESET
The reset pin of SSD2828 chip. This takes a string in the format
understood by 'name_to_gpio' function, e.g. PH1 for pin 1 of port H.
+config VIDEO_LCD_HITACHI_TX18D42VM
+ bool "Hitachi tx18d42vm LVDS LCD panel support"
+ depends on VIDEO
+ default n
+ ---help---
+ 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.
+
config VIDEO_LCD_SPI_CS
string "SPI CS pin for LCD related config job"
- depends on VIDEO_LCD_SSD2828
+ depends on VIDEO_LCD_SSD2828 || VIDEO_LCD_HITACHI_TX18D42VM
default ""
---help---
This is one of the SPI communication pins, involved in setting up a
@@ -48,7 +57,7 @@ config VIDEO_LCD_SPI_CS
config VIDEO_LCD_SPI_SCLK
string "SPI SCLK pin for LCD related config job"
- depends on VIDEO_LCD_SSD2828
+ depends on VIDEO_LCD_SSD2828 || VIDEO_LCD_HITACHI_TX18D42VM
default ""
---help---
This is one of the SPI communication pins, involved in setting up a
@@ -58,7 +67,7 @@ config VIDEO_LCD_SPI_SCLK
config VIDEO_LCD_SPI_MOSI
string "SPI MOSI pin for LCD related config job"
- depends on VIDEO_LCD_SSD2828
+ depends on VIDEO_LCD_SSD2828 || VIDEO_LCD_HITACHI_TX18D42VM
default ""
---help---
This is one of the SPI communication pins, involved in setting up a
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index 3629868..c3fcf45 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_VIDEO_COREBOOT) += coreboot_fb.o
obj-$(CONFIG_VIDEO_CT69000) += ct69000.o videomodes.o
obj-$(CONFIG_VIDEO_DA8XX) += da8xx-fb.o videomodes.o
obj-$(CONFIG_VIDEO_IMX25LCDC) += imx25lcdc.o videomodes.o
+obj-$(CONFIG_VIDEO_LCD_HITACHI_TX18D42VM) += hitachi_tx18d42vm_lcd.o
obj-$(CONFIG_VIDEO_LCD_SSD2828) += ssd2828.o
obj-$(CONFIG_VIDEO_MB862xx) += mb862xx.o videomodes.o
obj-$(CONFIG_VIDEO_MB86R0xGDC) += mb86r0xgdc.o videomodes.o
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 at 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;
+}
diff --git a/drivers/video/hitachi_tx18d42vm_lcd.h b/drivers/video/hitachi_tx18d42vm_lcd.h
new file mode 100644
index 0000000..1b72800
--- /dev/null
+++ b/drivers/video/hitachi_tx18d42vm_lcd.h
@@ -0,0 +1,9 @@
+/*
+ * Hitachi tx18d42vm LVDS LCD panel driver
+ *
+ * (C) Copyright 2015 Hans de Goede <hdegoede at redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+void hitachi_tx18d42vm_init(void);
--
2.1.0
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