Re: [PATCH 2/2] drm/tiny: add support for tft displays based on ilitek,ili9488

From: Michael Nazzareno Trimarchi
Date: Tue Oct 18 2022 - 14:31:44 EST


Hi

On Tue, Oct 18, 2022 at 6:46 PM Tommaso Merciai
<tommaso.merciai@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> This adds support for ilitek,ili9488 based displays with shift register
> in front of controller. Waveshare,pico-restouch-lcd-3.5 are such displays
>
> Signed-off-by: Tommaso Merciai <tommaso.merciai@xxxxxxxxxxxxxxxxxxxx>
> ---

Because I start to make it working this driver, I think that my
signed-off is missing here

> drivers/gpu/drm/tiny/Kconfig | 13 +
> drivers/gpu/drm/tiny/Makefile | 1 +
> drivers/gpu/drm/tiny/ili9488.c | 440 +++++++++++++++++++++++++++++++++
> 3 files changed, 454 insertions(+)
> create mode 100644 drivers/gpu/drm/tiny/ili9488.c
>
> diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig
> index 027cd87c3d0d7..6e708e8414806 100644
> --- a/drivers/gpu/drm/tiny/Kconfig
> +++ b/drivers/gpu/drm/tiny/Kconfig
> @@ -148,6 +148,19 @@ config TINYDRM_ILI9486
>
> If M is selected the module will be called ili9486.
>
> +config TINYDRM_ILI9488
> + tristate "DRM support for ILI9488 display panels"
> + depends on DRM && SPI
> + select DRM_KMS_HELPER
> + select DRM_GEM_CMA_HELPER
> + select DRM_MIPI_DBI
> + select BACKLIGHT_CLASS_DEVICE
> + help
> + DRM driver for the following Ilitek ILI9488 panels:
> + * LCD 3.5" 320x480 TFT (Waveshare Pico-ResTouch-LCD-3.5")
> +
> + If M is selected the module will be called ili9486.
> +
> config TINYDRM_MI0283QT
> tristate "DRM support for MI0283QT"
> depends on DRM && SPI
> diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile
> index 1d9d6227e7ab7..aad6683b2ac40 100644
> --- a/drivers/gpu/drm/tiny/Makefile
> +++ b/drivers/gpu/drm/tiny/Makefile
> @@ -11,6 +11,7 @@ obj-$(CONFIG_TINYDRM_ILI9163) += ili9163.o
> obj-$(CONFIG_TINYDRM_ILI9225) += ili9225.o
> obj-$(CONFIG_TINYDRM_ILI9341) += ili9341.o
> obj-$(CONFIG_TINYDRM_ILI9486) += ili9486.o
> +obj-$(CONFIG_TINYDRM_ILI9488) += ili9488.o
> obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o
> obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o
> obj-$(CONFIG_TINYDRM_ST7586) += st7586.o
> diff --git a/drivers/gpu/drm/tiny/ili9488.c b/drivers/gpu/drm/tiny/ili9488.c
> new file mode 100644
> index 0000000000000..b94d9d4ff4544
> --- /dev/null
> +++ b/drivers/gpu/drm/tiny/ili9488.c
> @@ -0,0 +1,440 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * DRM driver for Ilitek ILI9488 panels
> + *
> + * Copyright 2020 Kamlesh Gurudasani <kamlesh.gurudasani@xxxxxxxxx>
> + */

Code was changed a bit so please add copyright of me and you

> +
> +#include <linux/delay.h>
> +#include <linux/dma-buf.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/property.h>
> +#include <linux/spi/spi.h>
> +#include <video/mipi_display.h>
> +
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_drv.h>
> +#include <drm/drm_fb_cma_helper.h>
> +#include <drm/drm_gem_framebuffer_helper.h>
> +#include <drm/drm_fb_helper.h>
> +#include <drm/drm_damage_helper.h>
> +#include <drm/drm_framebuffer.h>
> +#include <drm/drm_gem_atomic_helper.h>
> +#include <drm/drm_gem_cma_helper.h>
> +#include <drm/drm_managed.h>
> +#include <drm/drm_mipi_dbi.h>
> +#include <drm/drm_modeset_helper.h>
> +
> +#define ILI9488_VCOM_CONTROL_1 0xC5
> +#define ILI9488_COLUMN_ADDRESS_SET 0x2A
> +#define ILI9488_PAGE_ADDRESS_SET 0x2B
> +#define ILI9488_MEMORY_WRITE 0x2C
> +#define ILI9488_POSITIVE_GAMMA_CORRECTION 0xE0
> +#define ILI9488_NEGATIVE_GAMMA_CORRECTION 0xE1
> +#define ILI9488_POWER_CONTROL_1 0xC0
> +#define ILI9488_POWER_CONTROL_2 0xC1
> +#define ILI9488_POWER_CONTROL_3 0xC2
> +#define ILI9488_MEM_ACCESS_CONTROL 0x36
> +#define ILI9488_COLMOD_PIXEL_FORMAT_SET 0x3A
> +#define ILI9488_INTERFACE_MODE_CONTROL 0xB0
> +#define ILI9488_FRAME_RATE_CONTROL_PARTIAL 0xB3
> +#define ILI9488_DISPLAY_INVERSION_ON 0x21
> +#define ILI9488_DISPLAY_INVERSION_CONTROL 0xB4
> +#define ILI9488_DISPLAY_FUNCTION_CONTROL 0xB6
> +#define ILI9488_ENTRY_MODE_SET 0xB7
> +#define ILI9488_HS_LANES_CONTROL 0xBE
> +#define ILI9488_SET_IMAGE_FUNCTION 0xE9
> +#define ILI9488_ADJUST_CONTROL_3 0xF7
> +#define ILI9488_DISPLAY_ON 0x29
> +#define ILI9488_DISPLAY_OFF 0x28
> +#define ILI9488_ENTER_SLEEP_MODE 0x10
> +#define ILI9488_DBI_BPP18 0x06
> +#define ILI9488_DBI_BPP16 0x05
> +#define ILI9488_DPI_BPP24 0x70
> +#define ILI9488_DPI_BPP18 0x60
> +#define ILI9488_DPI_BPP16 0x50
> +#define ILI9488_FRAME_RATE_CONTROL_NORMAL 0xB1
> +#define ILI9488_SLEEP_OUT 0x11
> +
> +#define ILI9488_MADCTL_RGB BIT(2)
> +#define ILI9488_MADCTL_BGR BIT(3)
> +#define ILI9488_MADCTL_MV BIT(5)
> +#define ILI9488_MADCTL_MX BIT(6)
> +#define ILI9488_MADCTL_MY BIT(7)
> +
> +static void ili9488_rgb565_to_rgb666_line(u8 *dst, u16 *sbuf,
> + unsigned int pixels)
> +{
> + unsigned int x;
> +
> + for (x = 0; x < pixels; x++) {
> + *dst++ = ((*sbuf & 0xF800) >> 8);
> + *dst++ = ((*sbuf & 0x07E0) >> 3);
> + *dst++ = ((*sbuf & 0x001F) << 3);
> + sbuf++;
> + }
> +}
> +
> +static void ili9488_rgb565_to_rgb666(u8 *dst, void *vaddr,
> + struct drm_framebuffer *fb,
> + struct drm_rect *rect)
> +{
> + unsigned long linepixels = drm_rect_width(rect);
> + unsigned long lines = drm_rect_height(rect);
> + size_t dst_len = linepixels * 3;
> + size_t src_len = linepixels * fb->format->cpp[0];
> + unsigned int y;
> + u16 *sbuf;
> +
> + /*
> + * The cma memory is write-combined so reads are uncached.
> + * Speed up by fetching one line at a time.
> + */
> + sbuf = kmalloc(src_len, GFP_KERNEL);
> + if (!sbuf)
> + return;
> +
> + memset(sbuf, 0, src_len);
> +

Is this really needed?. This will be write on the copy

> + vaddr += rect->y1 * fb->pitches[0] + rect->x1 * fb->format->cpp[0];
> + for (y = 0; y < lines; y++) {
> + memcpy(sbuf, vaddr, src_len);
> + ili9488_rgb565_to_rgb666_line(dst, sbuf, linepixels);
> + vaddr += fb->pitches[0];
> + dst += dst_len;
> + }
> + kfree(sbuf);
> +}
> +
> +static int ili9488_buf_copy(void *dst, struct drm_framebuffer *fb,
> + struct drm_rect *rect)
> +{
> + struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
> + void *src = cma_obj->vaddr;
> + int ret = 0;
> +
> + ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
> + if (ret)
> + return ret;
> +
> + switch (fb->format->format) {
> + case DRM_FORMAT_RGB565:
> + ili9488_rgb565_to_rgb666(dst, src, fb, rect);
> + break;
> + default:
> + dev_err_once(fb->dev->dev, "Format is not supported: %p4cc\n",
> + &fb->format->format);
> + return -EINVAL;
> + }
> +
> + drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
> +
> + return ret;
> +}
> +
> +static void ili9488_dbi_set_window_address(struct mipi_dbi_dev *dbidev,
> + unsigned int xs, unsigned int xe,
> + unsigned int ys, unsigned int ye)
> +{
> + struct mipi_dbi *dbi = &dbidev->dbi;
> +
> + xs += dbidev->left_offset;
> + xe += dbidev->left_offset;
> + ys += dbidev->top_offset;
> + ye += dbidev->top_offset;
> +
> + mipi_dbi_command(dbi, MIPI_DCS_SET_COLUMN_ADDRESS, (xs >> 8) & 0xff,
> + xs & 0xff, (xe >> 8) & 0xff, xe & 0xff);
> + mipi_dbi_command(dbi, MIPI_DCS_SET_PAGE_ADDRESS, (ys >> 8) & 0xff,
> + ys & 0xff, (ye >> 8) & 0xff, ye & 0xff);
> +}
> +

This is duplicated from the drm and maybe we can export from there

> +static void ili9488_fb_dirty(struct drm_framebuffer *fb, struct drm_rect *rect)
> +{
> + struct iosys_map map[DRM_FORMAT_MAX_PLANES];
> + struct iosys_map data[DRM_FORMAT_MAX_PLANES];
> + struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(fb->dev);
> + unsigned int height = rect->y2 - rect->y1;
> + unsigned int width = rect->x2 - rect->x1;
> + struct mipi_dbi *dbi = &dbidev->dbi;
> + int idx, ret = 0;
> + bool full;
> + void *tr;
> +
> + if (WARN_ON(!fb))
> + return;
> +
> + if (!drm_dev_enter(fb->dev, &idx))
> + return;
> +
> + ret = drm_gem_fb_vmap(fb, map, data);
> + if (ret)
> + goto err_drm_dev_exit;
> +
> + full = width == fb->width && height == fb->height;
> +
> + DRM_DEBUG_KMS("Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect));
> +
> + if (!dbi->dc || !full ||
> + fb->format->format == DRM_FORMAT_RGB565) {
> + tr = dbidev->tx_buf;
> + ret = ili9488_buf_copy(dbidev->tx_buf, fb, rect);
> + if (ret)
> + goto err_msg;
> + } else {
> + tr = data[0].vaddr; /* TODO: Use mapping abstraction properly */
> + }
> +
> + ili9488_dbi_set_window_address(dbidev, rect->x1, rect->x2 - 1, rect->y1,
> + rect->y2 - 1);
> +
> + ret = mipi_dbi_command_buf(dbi, MIPI_DCS_WRITE_MEMORY_START, tr,
> + width * height * 3);
> +err_msg:
> + if (ret)
> + drm_err_once(fb->dev, "Failed to update display %d\n", ret);
> +
> + drm_gem_fb_vunmap(fb, map);
> +
> +err_drm_dev_exit:
> + drm_dev_exit(idx);
> +}
> +
> +static void ili9488_pipe_update(struct drm_simple_display_pipe *pipe,
> + struct drm_plane_state *old_state)
> +{
> + struct drm_plane_state *state = pipe->plane.state;
> + struct drm_rect rect;
> +
> + if (!pipe->crtc.state->active)
> + return;
> +
> + if (drm_atomic_helper_damage_merged(old_state, state, &rect))
> + ili9488_fb_dirty(state->fb, &rect);
> +}
> +
> +static void ili9488_pipe_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 drm_framebuffer *fb = plane_state->fb;
> + struct mipi_dbi *dbi = &dbidev->dbi;
> + u8 addr_mode;
> + struct drm_rect rect = {
> + .x1 = 0,
> + .x2 = fb->width,
> + .y1 = 0,
> + .y2 = fb->height,
> + };

rect can be dropped

> + 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, ILI9488_DISPLAY_INVERSION_ON);
> + mipi_dbi_command(dbi, ILI9488_POWER_CONTROL_3, 0x33);
> + mipi_dbi_command(dbi, ILI9488_FRAME_RATE_CONTROL_NORMAL, 0xB0);
> + mipi_dbi_command(dbi, ILI9488_MEM_ACCESS_CONTROL, 0x28);
> +
> + mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT, 0x65);
> +
> + mipi_dbi_command(dbi, ILI9488_POSITIVE_GAMMA_CORRECTION,
> + 0x00, 0x13, 0x18, 0x04, 0x0F,
> + 0x06, 0x3A, 0x56, 0x4D, 0x03,
> + 0x0A, 0x06, 0x30, 0x3E, 0x0F);
> + mipi_dbi_command(dbi, ILI9488_NEGATIVE_GAMMA_CORRECTION,
> + 0x00, 0x13, 0x18, 0x01, 0x11,
> + 0x06, 0x38, 0x3A, 0x4D, 0x06,
> + 0x0D, 0x0B, 0x31, 0x37, 0x0F);
> +
> + mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT, MIPI_DCS_PIXEL_FMT_18BIT);
> + mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
> + msleep(120);
> + mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
> + msleep(100);
> +
> +out_enable:
> + switch (dbidev->rotation) {
> + default:
> + addr_mode = ILI9488_MADCTL_MX;
> + break;
> + case 90:
> + addr_mode = ILI9488_MADCTL_MV;
> + break;
> + case 180:
> + addr_mode = ILI9488_MADCTL_MY;
> + break;
> + case 270:
> + addr_mode = ILI9488_MADCTL_MV | ILI9488_MADCTL_MY |
> + ILI9488_MADCTL_MX;
> + break;
> + }
> + addr_mode |= ILI9488_MADCTL_BGR;
> + mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
> + ili9488_fb_dirty(fb, &rect);

This is not needed and and rect can be drop as I have on latest code

mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);

The flush should call the pipeline_update and you don't need to have
then anything more than this

Michael

> +out_exit:
> + drm_dev_exit(idx);
> +}
> +
> +static void ili9488_pipe_disable(struct drm_simple_display_pipe *pipe)
> +{
> + struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
> + /*
> + * This callback is not protected by drm_dev_enter/exit since we want to
> + * turn off the display on regular driver unload. It's highly unlikely
> + * that the underlying SPI controller is gone should this be called
> + * after unplug.
> + */
> +
> + DRM_DEBUG_KMS("\n");
> +
> + mipi_dbi_command(&dbidev->dbi, MIPI_DCS_SET_DISPLAY_OFF);
> +}
> +
> +static const u32 ili9488_formats[] = {
> + DRM_FORMAT_RGB565,
> +};
> +
> +static const struct drm_simple_display_pipe_funcs ili9488_pipe_funcs = {
> + .enable = ili9488_pipe_enable,
> + .disable = ili9488_pipe_disable,
> + .update = ili9488_pipe_update,
> +};
> +
> +static const struct drm_display_mode ili9488_mode = {
> + DRM_SIMPLE_MODE(320, 480, 49, 73),
> +};
> +
> +DEFINE_DRM_GEM_CMA_FOPS(ili9488_fops);
> +
> +static struct drm_driver ili9488_driver = {
> + .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
> + .fops = &ili9488_fops,
> + DRM_GEM_CMA_DRIVER_OPS_VMAP,
> + .debugfs_init = mipi_dbi_debugfs_init,
> + .name = "ili9488",
> + .desc = "Ilitek ILI9488",
> + .date = "20221017",
> + .major = 1,
> + .minor = 0,
> +};
> +
> +static const struct of_device_id ili9488_of_match[] = {
> + { .compatible = "waveshare,pico-rt-lcd-35" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, ili9488_of_match);
> +
> +static const struct spi_device_id ili9488_id[] = {
> + { "ili9488", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(spi, ili9488_id);
> +
> +static int ili9488_probe(struct spi_device *spi)
> +{
> + struct device *dev = &spi->dev;
> + struct mipi_dbi_dev *dbidev;
> + struct drm_device *drm;
> + struct mipi_dbi *dbi;
> + struct gpio_desc *dc;
> + u32 rotation = 0;
> + size_t bufsize;
> + int ret;
> +
> + dbidev = devm_drm_dev_alloc(dev, &ili9488_driver,
> + struct mipi_dbi_dev, drm);
> + if (IS_ERR(dbidev))
> + return PTR_ERR(dbidev);
> +
> + dbi = &dbidev->dbi;
> + drm = &dbidev->drm;
> +
> + bufsize = ili9488_mode.vdisplay * ili9488_mode.hdisplay * 3;
> +
> + dbi->reset = devm_gpiod_get(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_LOW);
> + if (IS_ERR(dc)) {
> + DRM_DEV_ERROR(dev, "Failed to get gpio 'dc'\n");
> + return PTR_ERR(dc);
> + }
> +
> + dbidev->backlight = devm_of_find_backlight(dev);
> + if (IS_ERR(dbidev->backlight))
> + return PTR_ERR(dbidev->backlight);
> +
> + device_property_read_u32(dev, "rotation", &rotation);
> +
> + ret = mipi_dbi_spi_init(spi, dbi, dc);
> + if (ret)
> + return ret;
> +
> + dbidev->drm.mode_config.preferred_depth = 16;
> +
> + ret = mipi_dbi_dev_init_with_formats(dbidev, &ili9488_pipe_funcs,
> + ili9488_formats,
> + ARRAY_SIZE(ili9488_formats),
> + &ili9488_mode, rotation, bufsize);
> + if (ret)
> + return ret;
> +
> + dbi->swap_bytes = true;
> + drm_mode_config_reset(drm);
> +
> + ret = drm_dev_register(drm, 0);
> + if (ret)
> + return ret;
> +
> + spi_set_drvdata(spi, drm);
> +
> + drm_fbdev_generic_setup(drm, 0);
> +
> + return 0;
> +}
> +
> +static void ili9488_remove(struct spi_device *spi)
> +{
> + struct drm_device *drm = spi_get_drvdata(spi);
> +
> + drm_dev_unplug(drm);
> + drm_atomic_helper_shutdown(drm);
> +}
> +
> +static void ili9488_shutdown(struct spi_device *spi)
> +{
> + drm_atomic_helper_shutdown(spi_get_drvdata(spi));
> +}
> +
> +static struct spi_driver ili9488_spi_driver = {
> + .driver = {
> + .name = "ili9488",
> + .owner = THIS_MODULE,
> + .of_match_table = ili9488_of_match,
> + },
> + .id_table = ili9488_id,
> + .probe = ili9488_probe,
> + .remove = ili9488_remove,
> + .shutdown = ili9488_shutdown,
> +};
> +module_spi_driver(ili9488_spi_driver);
> +
> +MODULE_DESCRIPTION("Ilitek ILI9488 DRM driver");
> +MODULE_AUTHOR("Kamlesh Gurudasani <kamlesh.gurudasani@xxxxxxxxx>");
> +MODULE_AUTHOR("Michael Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx>");
> +MODULE_AUTHOR("Tommaso Merciai <tommaso.merciai@xxxxxxxxxxxxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> \ No newline at end of file
> --
> 2.25.1
>


--
Michael Nazzareno Trimarchi
Co-Founder & Chief Executive Officer
M. +39 347 913 2170
michael@xxxxxxxxxxxxxxxxxxxx
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