[PATCH 5/6] drm/tinydrm: add support for LEGO MINDSTORMS EV3 LCD
David Lechner
david at lechnology.com
Sat Jul 29 12:17:49 PDT 2017
LEGO MINDSTORMS EV3 has an LCD with a ST7586 controller. This adds a new
module for the ST7586 controller with parameters for the EV3 LCD dispay.
Signed-off-by: David Lechner <david at lechnology.com>
---
.../devicetree/bindings/display/mipi-panel.txt | 2 +-
drivers/gpu/drm/tinydrm/Kconfig | 1 +
drivers/gpu/drm/tinydrm/mipi-panel.c | 87 ++++++++++++++++++++++
include/drm/tinydrm/st7586.h | 34 +++++++++
4 files changed, 123 insertions(+), 1 deletion(-)
create mode 100644 include/drm/tinydrm/st7586.h
diff --git a/Documentation/devicetree/bindings/display/mipi-panel.txt b/Documentation/devicetree/bindings/display/mipi-panel.txt
index 01d6ea9..ba8c8ab 100644
--- a/Documentation/devicetree/bindings/display/mipi-panel.txt
+++ b/Documentation/devicetree/bindings/display/mipi-panel.txt
@@ -1,7 +1,7 @@
MIPI DBI compatible display panel
Required properties:
-- compatible: "multi-inno,mi0283qt".
+- compatible: one of "lego,ev3-lcd", "multi-inno,mi0283qt".
The node for this driver must be a child node of a SPI controller, hence
all mandatory properties described in ../spi/spi-bus.txt must be specified.
diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
index 394519b..6e90bb5 100644
--- a/drivers/gpu/drm/tinydrm/Kconfig
+++ b/drivers/gpu/drm/tinydrm/Kconfig
@@ -20,6 +20,7 @@ config TINYDRM_MIPI_PANEL
DRM driver for the MIPI DBI compatible display panels.
Supported panels include:
+ * LEGO MINDSTORMS EV3
* Multi-Inno MI0283QT
If M is selected the module will be called mipi-panel.
diff --git a/drivers/gpu/drm/tinydrm/mipi-panel.c b/drivers/gpu/drm/tinydrm/mipi-panel.c
index 8aa1d8e..e3d5678 100644
--- a/drivers/gpu/drm/tinydrm/mipi-panel.c
+++ b/drivers/gpu/drm/tinydrm/mipi-panel.c
@@ -12,6 +12,7 @@
#include <drm/tinydrm/ili9341.h>
#include <drm/tinydrm/mipi-dbi.h>
+#include <drm/tinydrm/st7586.h>
#include <drm/tinydrm/tinydrm-helpers.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
@@ -23,6 +24,7 @@
enum mipi_panel_type {
MIPI_PANEL_TYPE_UNKNOWN,
+ MIPI_PANEL_TYPE_LEGO_EV3_LCD,
MIPI_PANEL_TYPE_MULTI_INNO_MI0283QT,
};
@@ -125,6 +127,84 @@ static int mipi_panel_init_ili9341(struct mipi_dbi *mipi)
return 0;
}
+static int mipi_panel_init_st7586(struct mipi_dbi *mipi)
+{
+ struct tinydrm_device *tdev = &mipi->tinydrm;
+ struct device *dev = tdev->drm->dev;
+ u8 addr_mode;
+ int ret;
+
+ DRM_DEBUG_KMS("\n");
+
+ ret = regulator_enable(mipi->regulator);
+ if (ret) {
+ dev_err(dev, "Failed to enable regulator %d\n", ret);
+ return ret;
+ }
+
+ /* Avoid flicker by skipping setup if the bootloader has done it */
+ if (mipi_dbi_display_is_on(mipi))
+ return 0;
+
+ mipi_dbi_hw_reset(mipi);
+ ret = mipi_dbi_command(mipi, ST7586_AUTO_READ_CTRL, 0x9f);
+ if (ret) {
+ dev_err(dev, "Error sending command %d\n", ret);
+ regulator_disable(mipi->regulator);
+ return ret;
+ }
+
+ mipi_dbi_command(mipi, ST7586_OTP_RW_CTRL, 0x00);
+
+ msleep(10);
+
+ mipi_dbi_command(mipi, ST7586_OTP_READ);
+
+ msleep(20);
+
+ mipi_dbi_command(mipi, ST7586_OTP_CTRL_OUT);
+ mipi_dbi_command(mipi, MIPI_DCS_EXIT_SLEEP_MODE);
+ mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);
+
+ msleep(50);
+
+ mipi_dbi_command(mipi, ST7586_SET_VOP_OFFSET, 0x00);
+ mipi_dbi_command(mipi, ST7586_SET_VOP, 0xe3, 0x00);
+ mipi_dbi_command(mipi, ST7586_SET_BIAS_SYSTEM, 0x02);
+ mipi_dbi_command(mipi, ST7586_SET_BOOST_LEVEL, 0x04);
+ mipi_dbi_command(mipi, ST7586_ENABLE_ANALOG, 0x1d);
+ mipi_dbi_command(mipi, ST7586_SET_NLINE_INV, 0x00);
+ mipi_dbi_command(mipi, ST7586_DISP_MODE_GRAY);
+ mipi_dbi_command(mipi, ST7586_ENABLE_DDRAM, 0x02);
+
+ switch (mipi->rotation) {
+ default:
+ addr_mode = 0x00;
+ break;
+ case 90:
+ addr_mode = ST7586_DISP_CTRL_MY;
+ break;
+ case 180:
+ addr_mode = ST7586_DISP_CTRL_MX | ST7586_DISP_CTRL_MY;
+ break;
+ case 270:
+ addr_mode = ST7586_DISP_CTRL_MX;
+ break;
+ }
+ mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
+
+ mipi_dbi_command(mipi, ST7586_SET_DISP_DUTY, 0x7f);
+ mipi_dbi_command(mipi, ST7586_SET_PART_DISP, 0xa0);
+ mipi_dbi_command(mipi, MIPI_DCS_SET_PARTIAL_AREA, 0x00, 0x00, 0x00, 0x77);
+ mipi_dbi_command(mipi, MIPI_DCS_EXIT_INVERT_MODE);
+
+ msleep(100);
+
+ mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON);
+
+ return 0;
+}
+
static void mipi_panel_fini(void *data)
{
struct mipi_dbi *mipi = data;
@@ -141,6 +221,11 @@ static const struct drm_simple_display_pipe_funcs mipi_panel_pipe_funcs = {
};
static const struct mipi_panel_info mipi_panel_infos[] = {
+ [MIPI_PANEL_TYPE_LEGO_EV3_LCD] = {
+ .init = mipi_panel_init_st7586,
+ .mode = { TINYDRM_MODE(178, 128, 37, 27) },
+ .pixel_fmt = MIPI_DCS_PIXEL_FMT_ST7586_332,
+ },
[MIPI_PANEL_TYPE_MULTI_INNO_MI0283QT] = {
.init = mipi_panel_init_ili9341,
.mode = { TINYDRM_MODE(320, 240, 58, 43) },
@@ -165,12 +250,14 @@ static struct drm_driver mipi_panel_driver = {
};
static const struct of_device_id mipi_panel_of_match[] = {
+ { .compatible = "lego,ev3-lcd" },
{ .compatible = "multi-inno,mi0283qt" },
{},
};
MODULE_DEVICE_TABLE(of, mipi_panel_of_match);
static const struct spi_device_id mipi_panel_id[] = {
+ { "ev3-lcd", MIPI_PANEL_TYPE_LEGO_EV3_LCD },
{ "mi0283qt", MIPI_PANEL_TYPE_MULTI_INNO_MI0283QT },
{ },
};
diff --git a/include/drm/tinydrm/st7586.h b/include/drm/tinydrm/st7586.h
new file mode 100644
index 0000000..18fb56b
--- /dev/null
+++ b/include/drm/tinydrm/st7586.h
@@ -0,0 +1,34 @@
+/*
+ * ST7586 LCD controller
+ *
+ * Copyright (C) 2017 David Lechner <david at lechnology.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __LINUX_ST7856_H
+#define __LINUX_ST7856_H
+
+#define ST7586_DISP_MODE_GRAY 0x38
+#define ST7586_DISP_MODE_MONO 0x39
+#define ST7586_ENABLE_DDRAM 0x3a
+#define ST7586_SET_DISP_DUTY 0xb0
+#define ST7586_SET_PART_DISP 0xb4
+#define ST7586_SET_NLINE_INV 0xb5
+#define ST7586_SET_VOP 0xc0
+#define ST7586_SET_BIAS_SYSTEM 0xc3
+#define ST7586_SET_BOOST_LEVEL 0xc4
+#define ST7586_SET_VOP_OFFSET 0xc7
+#define ST7586_ENABLE_ANALOG 0xd0
+#define ST7586_AUTO_READ_CTRL 0xd7
+#define ST7586_OTP_RW_CTRL 0xe0
+#define ST7586_OTP_CTRL_OUT 0xe1
+#define ST7586_OTP_READ 0xe3
+
+#define ST7586_DISP_CTRL_MX BIT(6)
+#define ST7586_DISP_CTRL_MY BIT(7)
+
+#endif /* __LINUX_ST7856_H */
--
2.7.4
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