[PATCH 2/3] drm/tiny: Add driver for ili9341 with parallel bus

From: mdurnev
Date: Wed Nov 18 2020 - 02:37:26 EST

From: Mikhail Durnev <mikhail_durnev@xxxxxxxxxx>

MRB2801 display module [1] is an example of ILI9341 display that connects to
Intel 8080 parallel bus. Its connector is compatible with the ALIENTEK STM32
development board.

It can be used with the drm/mipi-dbi bus driver if the bus is emulated with
GPIO.

[1] http://www.lcdwiki.com/2.8inch_16BIT_Module_ILI9341_SKU:MRB2801

Signed-off-by: Mikhail Durnev <mikhail_durnev@xxxxxxxxxx>
---
drivers/gpu/drm/tiny/Kconfig | 13 ++
drivers/gpu/drm/tiny/Makefile | 1 +
drivers/gpu/drm/tiny/ili9341_gpio.c | 290 ++++++++++++++++++++++++++++++++++++
3 files changed, 304 insertions(+)
create mode 100644 drivers/gpu/drm/tiny/ili9341_gpio.c

diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig
index 2b6414f..e48e268 100644
--- a/drivers/gpu/drm/tiny/Kconfig
+++ b/drivers/gpu/drm/tiny/Kconfig
@@ -66,6 +66,19 @@ config TINYDRM_ILI9341

If M is selected the module will be called ili9341.

+config TINYDRM_ILI9341_GPIO
+ tristate "DRM support for ILI9341 display panels with parallel bus interface over GPIO"
+ depends on DRM
+ select DRM_KMS_HELPER
+ select DRM_KMS_CMA_HELPER
+ select DRM_MIPI_DBI
+ select BACKLIGHT_CLASS_DEVICE
+ help
+ DRM driver for the following Ilitek ILI9341 panels:
+ * MRB2801 2.8" 240x320 TFT
+
+ If M is selected the module will be called ili9341_gpio.
+
config TINYDRM_ILI9486
tristate "DRM support for ILI9486 display panels"
depends on DRM && SPI
diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile
index 6ae4e9e5..1ad2c0d 100644
--- a/drivers/gpu/drm/tiny/Makefile
+++ b/drivers/gpu/drm/tiny/Makefile
@@ -5,6 +5,7 @@ obj-$(CONFIG_DRM_GM12U320) += gm12u320.o
obj-$(CONFIG_TINYDRM_HX8357D) += hx8357d.o
obj-$(CONFIG_TINYDRM_ILI9225) += ili9225.o
obj-$(CONFIG_TINYDRM_ILI9341) += ili9341.o
+obj-$(CONFIG_TINYDRM_ILI9341_GPIO) += ili9341_gpio.o
obj-$(CONFIG_TINYDRM_ILI9486) += ili9486.o
obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o
obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o
diff --git a/drivers/gpu/drm/tiny/ili9341_gpio.c b/drivers/gpu/drm/tiny/ili9341_gpio.c
new file mode 100644
index 0000000..de8a63b8
--- /dev/null
+++ b/drivers/gpu/drm/tiny/ili9341_gpio.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * DRM driver for Ilitek ILI9341 panels with parallel bus interface
+ *
+ * Copyright 2020 Mikhail Durnev <mikhail_durnev@xxxxxxxxxx>
+ *
+ * Based on ili9341.c:
+ * Copyright 2018 David Lechner <david@xxxxxxxxxxxxxx>
+ *
+ * Based on mi0283qt.c:
+ * Copyright 2016 Noralf Trønnes
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_mipi_dbi.h>
+#include <drm/drm_modeset_helper.h>
+#include <video/mipi_display.h>
+
+#define ILI9341_FRMCTR1 0xb1
+#define ILI9341_DISCTRL 0xb6
+#define ILI9341_ETMOD 0xb7
+
+#define ILI9341_PWCTRL1 0xc0
+#define ILI9341_PWCTRL2 0xc1
+#define ILI9341_VMCTRL1 0xc5
+#define ILI9341_VMCTRL2 0xc7
+#define ILI9341_PWCTRLA 0xcb
+#define ILI9341_PWCTRLB 0xcf
+
+#define ILI9341_PGAMCTRL 0xe0
+#define ILI9341_NGAMCTRL 0xe1
+#define ILI9341_DTCTRLA 0xe8
+#define ILI9341_DTCTRLB 0xea
+#define ILI9341_PWRSEQ 0xed
+
+#define ILI9341_EN3GAM 0xf2
+#define ILI9341_PUMPCTRL 0xf7
+
+#define ILI9341_MADCTL_BGR BIT(3)
+#define ILI9341_MADCTL_MV BIT(5)
+#define ILI9341_MADCTL_MX BIT(6)
+#define ILI9341_MADCTL_MY BIT(7)
+
+static void yx240qv29_enable(struct drm_simple_display_pipe *pipe,
+ struct drm_crtc_state *crtc_state,
+ struct drm_plane_state *plane_state)
+{
+ struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
+ struct mipi_dbi *dbi = &dbidev->dbi;
+ u8 addr_mode;
+ int ret, idx;
+
+ if (!drm_dev_enter(pipe->crtc.dev, &idx))
+ return;
+
+ DRM_DEBUG_KMS("\n");
+
+ ret = mipi_dbi_poweron_conditional_reset(dbidev);
+ if (ret < 0)
+ goto out_exit;
+ if (ret == 1)
+ goto out_enable;
+
+ mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
+
+ mipi_dbi_command(dbi, ILI9341_PWCTRLB, 0x00, 0xc1, 0x30);
+ mipi_dbi_command(dbi, ILI9341_PWRSEQ, 0x64, 0x03, 0x12, 0x81);
+ mipi_dbi_command(dbi, ILI9341_DTCTRLA, 0x85, 0x00, 0x78);
+ mipi_dbi_command(dbi, ILI9341_PWCTRLA, 0x39, 0x2c, 0x00, 0x34, 0x02);
+ mipi_dbi_command(dbi, ILI9341_PUMPCTRL, 0x20);
+ mipi_dbi_command(dbi, ILI9341_DTCTRLB, 0x00, 0x00);
+
+ /* Power Control */
+ mipi_dbi_command(dbi, ILI9341_PWCTRL1, 0x23);
+ mipi_dbi_command(dbi, ILI9341_PWCTRL2, 0x10);
+ /* VCOM */
+ mipi_dbi_command(dbi, ILI9341_VMCTRL1, 0x3e, 0x28);
+ mipi_dbi_command(dbi, ILI9341_VMCTRL2, 0x86);
+
+ /* Memory Access Control */
+ mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT, MIPI_DCS_PIXEL_FMT_16BIT);
+
+ /* Frame Rate */
+ mipi_dbi_command(dbi, ILI9341_FRMCTR1, 0x00, 0x1b);
+
+ /* Gamma */
+ mipi_dbi_command(dbi, ILI9341_EN3GAM, 0x00);
+ mipi_dbi_command(dbi, MIPI_DCS_SET_GAMMA_CURVE, 0x01);
+ mipi_dbi_command(dbi, ILI9341_PGAMCTRL,
+ 0x0f, 0x31, 0x2b, 0x0c, 0x0e, 0x08, 0x4e, 0xf1,
+ 0x37, 0x07, 0x10, 0x03, 0x0e, 0x09, 0x00);
+ mipi_dbi_command(dbi, ILI9341_NGAMCTRL,
+ 0x00, 0x0e, 0x14, 0x03, 0x11, 0x07, 0x31, 0xc1,
+ 0x48, 0x08, 0x0f, 0x0c, 0x31, 0x36, 0x0f);
+
+ /* DDRAM */
+ mipi_dbi_command(dbi, ILI9341_ETMOD, 0x07);
+
+ /* Display */
+ mipi_dbi_command(dbi, ILI9341_DISCTRL, 0x08, 0x82, 0x27, 0x00);
+ mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+ msleep(100);
+
+ mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
+ msleep(100);
+
+out_enable:
+ switch (dbidev->rotation) {
+ default:
+ addr_mode = ILI9341_MADCTL_MX;
+ break;
+ case 90:
+ addr_mode = ILI9341_MADCTL_MV;
+ break;
+ case 180:
+ addr_mode = ILI9341_MADCTL_MY;
+ break;
+ case 270:
+ addr_mode = ILI9341_MADCTL_MV | ILI9341_MADCTL_MY |
+ ILI9341_MADCTL_MX;
+ break;
+ }
+ addr_mode |= ILI9341_MADCTL_BGR;
+ mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
+ mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
+out_exit:
+ drm_dev_exit(idx);
+}
+
+static const struct drm_simple_display_pipe_funcs ili9341gpio_pipe_funcs = {
+ .enable = yx240qv29_enable,
+ .disable = mipi_dbi_pipe_disable,
+ .update = mipi_dbi_pipe_update,
+ .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
+};
+
+static const struct drm_display_mode yx240qv29_mode = {
+ DRM_SIMPLE_MODE(240, 320, 37, 49),
+};
+
+DEFINE_DRM_GEM_CMA_FOPS(ili9341gpio_fops);
+
+static struct drm_driver ili9341gpio_driver = {
+ .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
+ .fops = &ili9341gpio_fops,
+ .release = mipi_dbi_release,
+ DRM_GEM_CMA_VMAP_DRIVER_OPS,
+ .debugfs_init = mipi_dbi_debugfs_init,
+ .name = "ili9341gpio",
+ .desc = "Ilitek ILI9341",
+ .date = "20201114",
+ .major = 1,
+ .minor = 0,
+};
+
+static const struct of_device_id ili9341gpio_of_match[] = {
+ { .compatible = "ronbo,mrb2801" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ili9341gpio_of_match);
+
+static int ili9341gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mipi_dbi_dev *dbidev;
+ struct drm_device *drm;
+ struct mipi_dbi *dbi;
+ struct gpio_desc *dc;
+ struct gpio_desc *wr;
+ struct gpio_descs *db;
+ u32 rotation = 0;
+ u32 wr_delays[2] = {15, 60};
+ int ret;
+
+ dbidev = kzalloc(sizeof(*dbidev), GFP_KERNEL);
+ if (!dbidev)
+ return -ENOMEM;
+
+ dbi = &dbidev->dbi;
+ drm = &dbidev->drm;
+ ret = devm_drm_dev_init(dev, drm, &ili9341gpio_driver);
+ if (ret) {
+ kfree(dbidev);
+ return ret;
+ }
+
+ drm_mode_config_init(drm);
+
+ dbi->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(dbi->reset)) {
+ DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
+ return PTR_ERR(dbi->reset);
+ }
+
+ dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_HIGH);
+ if (IS_ERR(dc)) {
+ DRM_DEV_ERROR(dev, "Failed to get gpio 'dc'\n");
+ return PTR_ERR(dc);
+ }
+
+ wr = devm_gpiod_get(dev, "wr", GPIOD_OUT_HIGH);
+ if (IS_ERR(wr)) {
+ DRM_DEV_ERROR(dev, "Failed to get gpio 'wr'\n");
+ return PTR_ERR(wr);
+ }
+
+ db = devm_gpiod_get_array(dev, "db", GPIOD_OUT_LOW);
+ if (IS_ERR(db)) {
+ DRM_DEV_ERROR(dev, "Failed to get gpio 'db'\n");
+ return PTR_ERR(db);
+ }
+ if (db->ndescs != 16 && db->ndescs != 8) {
+ /*
+ * The data bus can be either 8 or 16 bits wide.
+ * ILI9341 can work with 6, 8, 9, 16, and 18-bit parallel interfaces,
+ * but the MRB2801 board supports only 8 or 16-bit interfaces.
+ */
+ DRM_DEV_ERROR(dev, "Wrong number of bits in gpio 'db': %u\n", db->ndescs);
+ return PTR_ERR(db);
+ }
+
+ dbidev->backlight = devm_of_find_backlight(dev);
+ if (IS_ERR(dbidev->backlight))
+ return PTR_ERR(dbidev->backlight);
+
+ device_property_read_u32(dev, "rotation", &rotation);
+
+ device_property_read_u32_array(dev, "wr-up-down-delays", wr_delays, 2);
+
+ ret = mipi_dbi_gpio_init(dbi, dc, wr, db, wr_delays[0], wr_delays[1]);
+ if (ret)
+ return ret;
+
+ ret = mipi_dbi_dev_init(dbidev, &ili9341gpio_pipe_funcs, &yx240qv29_mode, rotation);
+ if (ret)
+ return ret;
+
+ drm_mode_config_reset(drm);
+
+ ret = drm_dev_register(drm, 0);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, drm);
+
+ drm_fbdev_generic_setup(drm, 0);
+
+ return 0;
+}
+
+static int ili9341gpio_remove(struct platform_device *pdev)
+{
+ struct drm_device *drm = platform_get_drvdata(pdev);
+
+ drm_dev_unplug(drm);
+ drm_atomic_helper_shutdown(drm);
+
+ return 0;
+}
+
+static void ili9341gpio_shutdown(struct platform_device *pdev)
+{
+ drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
+}
+
+static struct platform_driver ili9341gpio_platform_driver = {
+ .driver = {
+ .name = "ili9341gpio",
+ .of_match_table = ili9341gpio_of_match,
+ },
+ .probe = ili9341gpio_probe,
+ .remove = ili9341gpio_remove,
+ .shutdown = ili9341gpio_shutdown,
+};
+module_platform_driver(ili9341gpio_platform_driver);
+
+MODULE_DESCRIPTION("Ilitek ILI9341 8/16-bit DRM driver");
+MODULE_AUTHOR("Mikhail Durnev <mikhail_durnev@xxxxxxxxxx>");
+MODULE_LICENSE("GPL");
--
2.7.4