drivers/gpu/drm/tinydrm/ili9225.c - third_party/kernel - Git at Google

 /*
  * DRM driver for Ilitek ILI9225 panels
  *
  * Copyright 2017 David Lechner <david@lechnology.com>
  *
  * Some code copied from mipi-dbi.c
  * Copyright 2016 Noralf Trønnes
  *
  * 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.
  */

 #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_fb_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/tinydrm/mipi-dbi.h>
 #include <drm/tinydrm/tinydrm-helpers.h>

 #define ILI9225_DRIVER_READ_CODE	0x00
 #define ILI9225_DRIVER_OUTPUT_CONTROL	0x01
 #define ILI9225_LCD_AC_DRIVING_CONTROL	0x02
 #define ILI9225_ENTRY_MODE		0x03
 #define ILI9225_DISPLAY_CONTROL_1	0x07
 #define ILI9225_BLANK_PERIOD_CONTROL_1	0x08
 #define ILI9225_FRAME_CYCLE_CONTROL	0x0b
 #define ILI9225_INTERFACE_CONTROL	0x0c
 #define ILI9225_OSCILLATION_CONTROL	0x0f
 #define ILI9225_POWER_CONTROL_1		0x10
 #define ILI9225_POWER_CONTROL_2		0x11
 #define ILI9225_POWER_CONTROL_3		0x12
 #define ILI9225_POWER_CONTROL_4		0x13
 #define ILI9225_POWER_CONTROL_5		0x14
 #define ILI9225_VCI_RECYCLING		0x15
 #define ILI9225_RAM_ADDRESS_SET_1	0x20
 #define ILI9225_RAM_ADDRESS_SET_2	0x21
 #define ILI9225_WRITE_DATA_TO_GRAM	0x22
 #define ILI9225_SOFTWARE_RESET		0x28
 #define ILI9225_GATE_SCAN_CONTROL	0x30
 #define ILI9225_VERTICAL_SCROLL_1	0x31
 #define ILI9225_VERTICAL_SCROLL_2	0x32
 #define ILI9225_VERTICAL_SCROLL_3	0x33
 #define ILI9225_PARTIAL_DRIVING_POS_1	0x34
 #define ILI9225_PARTIAL_DRIVING_POS_2	0x35
 #define ILI9225_HORIZ_WINDOW_ADDR_1	0x36
 #define ILI9225_HORIZ_WINDOW_ADDR_2	0x37
 #define ILI9225_VERT_WINDOW_ADDR_1	0x38
 #define ILI9225_VERT_WINDOW_ADDR_2	0x39
 #define ILI9225_GAMMA_CONTROL_1		0x50
 #define ILI9225_GAMMA_CONTROL_2		0x51
 #define ILI9225_GAMMA_CONTROL_3		0x52
 #define ILI9225_GAMMA_CONTROL_4		0x53
 #define ILI9225_GAMMA_CONTROL_5		0x54
 #define ILI9225_GAMMA_CONTROL_6		0x55
 #define ILI9225_GAMMA_CONTROL_7		0x56
 #define ILI9225_GAMMA_CONTROL_8		0x57
 #define ILI9225_GAMMA_CONTROL_9		0x58
 #define ILI9225_GAMMA_CONTROL_10	0x59

 static inline int ili9225_command(struct mipi_dbi *mipi, u8 cmd, u16 data)
 {
 	u8 par[2] = { data >> 8, data & 0xff };

 	return mipi_dbi_command_buf(mipi, cmd, par, 2);
 }

 static int ili9225_fb_dirty(struct drm_framebuffer *fb,
 			    struct drm_file *file_priv, unsigned int flags,
 			    unsigned int color, struct drm_clip_rect *clips,
 			    unsigned int num_clips)
 {
 	struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
 	struct tinydrm_device *tdev = fb->dev->dev_private;
 	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
 	bool swap = mipi->swap_bytes;
 	struct drm_clip_rect clip;
 	u16 x_start, y_start;
 	u16 x1, x2, y1, y2;
 	int ret = 0;
 	bool full;
 	void *tr;

 	if (!mipi->enabled)
 		return 0;

 	full = tinydrm_merge_clips(&clip, clips, num_clips, flags,
 				   fb->width, fb->height);

 	DRM_DEBUG("Flushing [FB:%d] x1=%u, x2=%u, y1=%u, y2=%u\n", fb->base.id,
 		  clip.x1, clip.x2, clip.y1, clip.y2);

 	if (!mipi->dc || !full || swap ||
 	    fb->format->format == DRM_FORMAT_XRGB8888) {
 		tr = mipi->tx_buf;
 		ret = mipi_dbi_buf_copy(mipi->tx_buf, fb, &clip, swap);
 		if (ret)
 			return ret;
 	} else {
 		tr = cma_obj->vaddr;
 	}

 	switch (mipi->rotation) {
 	default:
 		x1 = clip.x1;
 		x2 = clip.x2 - 1;
 		y1 = clip.y1;
 		y2 = clip.y2 - 1;
 		x_start = x1;
 		y_start = y1;
 		break;
 	case 90:
 		x1 = clip.y1;
 		x2 = clip.y2 - 1;
 		y1 = fb->width - clip.x2;
 		y2 = fb->width - clip.x1 - 1;
 		x_start = x1;
 		y_start = y2;
 		break;
 	case 180:
 		x1 = fb->width - clip.x2;
 		x2 = fb->width - clip.x1 - 1;
 		y1 = fb->height - clip.y2;
 		y2 = fb->height - clip.y1 - 1;
 		x_start = x2;
 		y_start = y2;
 		break;
 	case 270:
 		x1 = fb->height - clip.y2;
 		x2 = fb->height - clip.y1 - 1;
 		y1 = clip.x1;
 		y2 = clip.x2 - 1;
 		x_start = x2;
 		y_start = y1;
 		break;
 	}

 	ili9225_command(mipi, ILI9225_HORIZ_WINDOW_ADDR_1, x2);
 	ili9225_command(mipi, ILI9225_HORIZ_WINDOW_ADDR_2, x1);
 	ili9225_command(mipi, ILI9225_VERT_WINDOW_ADDR_1, y2);
 	ili9225_command(mipi, ILI9225_VERT_WINDOW_ADDR_2, y1);

 	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_1, x_start);
 	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_2, y_start);

 	ret = mipi_dbi_command_buf(mipi, ILI9225_WRITE_DATA_TO_GRAM, tr,
 				(clip.x2 - clip.x1) * (clip.y2 - clip.y1) * 2);

 	return ret;
 }

 static const struct drm_framebuffer_funcs ili9225_fb_funcs = {
 	.destroy	= drm_gem_fb_destroy,
 	.create_handle	= drm_gem_fb_create_handle,
 	.dirty		= tinydrm_fb_dirty,
 };

 static void ili9225_pipe_enable(struct drm_simple_display_pipe *pipe,
 				struct drm_crtc_state *crtc_state,
 				struct drm_plane_state *plane_state)
 {
 	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
 	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
 	struct device *dev = tdev->drm->dev;
 	int ret;
 	u8 am_id;

 	DRM_DEBUG_KMS("\n");

 	mipi_dbi_hw_reset(mipi);

 	/*
 	 * There don't seem to be two example init sequences that match, so
 	 * using the one from the popular Arduino library for this display.
 	 * https://github.com/Nkawu/TFT_22_ILI9225/blob/master/src/TFT_22_ILI9225.cpp
 	 */

 	ret = ili9225_command(mipi, ILI9225_POWER_CONTROL_1, 0x0000);
 	if (ret) {
 		DRM_DEV_ERROR(dev, "Error sending command %d\n", ret);
 		return;
 	}
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x0000);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_3, 0x0000);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_4, 0x0000);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_5, 0x0000);

 	msleep(40);

 	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x0018);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_3, 0x6121);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_4, 0x006f);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_5, 0x495f);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_1, 0x0800);

 	msleep(10);

 	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x103b);

 	msleep(50);

 	switch (mipi->rotation) {
 	default:
 		am_id = 0x30;
 		break;
 	case 90:
 		am_id = 0x18;
 		break;
 	case 180:
 		am_id = 0x00;
 		break;
 	case 270:
 		am_id = 0x28;
 		break;
 	}
 	ili9225_command(mipi, ILI9225_DRIVER_OUTPUT_CONTROL, 0x011c);
 	ili9225_command(mipi, ILI9225_LCD_AC_DRIVING_CONTROL, 0x0100);
 	ili9225_command(mipi, ILI9225_ENTRY_MODE, 0x1000 | am_id);
 	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x0000);
 	ili9225_command(mipi, ILI9225_BLANK_PERIOD_CONTROL_1, 0x0808);
 	ili9225_command(mipi, ILI9225_FRAME_CYCLE_CONTROL, 0x1100);
 	ili9225_command(mipi, ILI9225_INTERFACE_CONTROL, 0x0000);
 	ili9225_command(mipi, ILI9225_OSCILLATION_CONTROL, 0x0d01);
 	ili9225_command(mipi, ILI9225_VCI_RECYCLING, 0x0020);
 	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_1, 0x0000);
 	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_2, 0x0000);

 	ili9225_command(mipi, ILI9225_GATE_SCAN_CONTROL, 0x0000);
 	ili9225_command(mipi, ILI9225_VERTICAL_SCROLL_1, 0x00db);
 	ili9225_command(mipi, ILI9225_VERTICAL_SCROLL_2, 0x0000);
 	ili9225_command(mipi, ILI9225_VERTICAL_SCROLL_3, 0x0000);
 	ili9225_command(mipi, ILI9225_PARTIAL_DRIVING_POS_1, 0x00db);
 	ili9225_command(mipi, ILI9225_PARTIAL_DRIVING_POS_2, 0x0000);

 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_1, 0x0000);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_2, 0x0808);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_3, 0x080a);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_4, 0x000a);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_5, 0x0a08);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_6, 0x0808);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_7, 0x0000);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_8, 0x0a00);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_9, 0x0710);
 	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_10, 0x0710);

 	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x0012);

 	msleep(50);

 	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x1017);

 	mipi_dbi_enable_flush(mipi, crtc_state, plane_state);
 }

 static void ili9225_pipe_disable(struct drm_simple_display_pipe *pipe)
 {
 	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
 	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);

 	DRM_DEBUG_KMS("\n");

 	if (!mipi->enabled)
 		return;

 	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x0000);
 	msleep(50);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x0007);
 	msleep(50);
 	ili9225_command(mipi, ILI9225_POWER_CONTROL_1, 0x0a02);

 	mipi->enabled = false;
 }

 static int ili9225_dbi_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par,
 			       size_t num)
 {
 	struct spi_device *spi = mipi->spi;
 	unsigned int bpw = 8;
 	u32 speed_hz;
 	int ret;

 	gpiod_set_value_cansleep(mipi->dc, 0);
 	speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1);
 	ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, cmd, 1);
 	if (ret || !num)
 		return ret;

 	if (*cmd == ILI9225_WRITE_DATA_TO_GRAM && !mipi->swap_bytes)
 		bpw = 16;

 	gpiod_set_value_cansleep(mipi->dc, 1);
 	speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num);

 	return tinydrm_spi_transfer(spi, speed_hz, NULL, bpw, par, num);
 }

 static const u32 ili9225_formats[] = {
 	DRM_FORMAT_RGB565,
 	DRM_FORMAT_XRGB8888,
 };

 static int ili9225_init(struct device *dev, struct mipi_dbi *mipi,
 			const struct drm_simple_display_pipe_funcs *pipe_funcs,
 			struct drm_driver *driver,
 			const struct drm_display_mode *mode,
 			unsigned int rotation)
 {
 	size_t bufsize = mode->vdisplay * mode->hdisplay * sizeof(u16);
 	struct tinydrm_device *tdev = &mipi->tinydrm;
 	int ret;

 	if (!mipi->command)
 		return -EINVAL;

 	mutex_init(&mipi->cmdlock);

 	mipi->tx_buf = devm_kmalloc(dev, bufsize, GFP_KERNEL);
 	if (!mipi->tx_buf)
 		return -ENOMEM;

 	ret = devm_tinydrm_init(dev, tdev, &ili9225_fb_funcs, driver);
 	if (ret)
 		return ret;

 	tdev->fb_dirty = ili9225_fb_dirty;

 	ret = tinydrm_display_pipe_init(tdev, pipe_funcs,
 					DRM_MODE_CONNECTOR_VIRTUAL,
 					ili9225_formats,
 					ARRAY_SIZE(ili9225_formats), mode,
 					rotation);
 	if (ret)
 		return ret;

 	tdev->drm->mode_config.preferred_depth = 16;
 	mipi->rotation = rotation;

 	drm_mode_config_reset(tdev->drm);

 	DRM_DEBUG_KMS("preferred_depth=%u, rotation = %u\n",
 		      tdev->drm->mode_config.preferred_depth, rotation);

 	return 0;
 }

 static const struct drm_simple_display_pipe_funcs ili9225_pipe_funcs = {
 	.enable		= ili9225_pipe_enable,
 	.disable	= ili9225_pipe_disable,
 	.update		= tinydrm_display_pipe_update,
 	.prepare_fb	= drm_gem_fb_simple_display_pipe_prepare_fb,
 };

 static const struct drm_display_mode ili9225_mode = {
 	TINYDRM_MODE(176, 220, 35, 44),
 };

 DEFINE_DRM_GEM_CMA_FOPS(ili9225_fops);

 static struct drm_driver ili9225_driver = {
 	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
 				  DRIVER_ATOMIC,
 	.fops			= &ili9225_fops,
 	TINYDRM_GEM_DRIVER_OPS,
 	.name			= "ili9225",
 	.desc			= "Ilitek ILI9225",
 	.date			= "20171106",
 	.major			= 1,
 	.minor			= 0,
 };

 static const struct of_device_id ili9225_of_match[] = {
 	{ .compatible = "vot,v220hf01a-t" },
 	{},
 };
 MODULE_DEVICE_TABLE(of, ili9225_of_match);

 static const struct spi_device_id ili9225_id[] = {
 	{ "v220hf01a-t", 0 },
 	{ },
 };
 MODULE_DEVICE_TABLE(spi, ili9225_id);

 static int ili9225_probe(struct spi_device *spi)
 {
 	struct device *dev = &spi->dev;
 	struct mipi_dbi *mipi;
 	struct gpio_desc *rs;
 	u32 rotation = 0;
 	int ret;

 	mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
 	if (!mipi)
 		return -ENOMEM;

 	mipi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
 	if (IS_ERR(mipi->reset)) {
 		DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
 		return PTR_ERR(mipi->reset);
 	}

 	rs = devm_gpiod_get(dev, "rs", GPIOD_OUT_LOW);
 	if (IS_ERR(rs)) {
 		DRM_DEV_ERROR(dev, "Failed to get gpio 'rs'\n");
 		return PTR_ERR(rs);
 	}

 	device_property_read_u32(dev, "rotation", &rotation);

 	ret = mipi_dbi_spi_init(spi, mipi, rs);
 	if (ret)
 		return ret;

 	/* override the command function set in  mipi_dbi_spi_init() */
 	mipi->command = ili9225_dbi_command;

 	ret = ili9225_init(&spi->dev, mipi, &ili9225_pipe_funcs,
 			   &ili9225_driver, &ili9225_mode, rotation);
 	if (ret)
 		return ret;

 	spi_set_drvdata(spi, mipi);

 	return devm_tinydrm_register(&mipi->tinydrm);
 }

 static void ili9225_shutdown(struct spi_device *spi)
 {
 	struct mipi_dbi *mipi = spi_get_drvdata(spi);

 	tinydrm_shutdown(&mipi->tinydrm);
 }

 static struct spi_driver ili9225_spi_driver = {
 	.driver = {
 		.name = "ili9225",
 		.owner = THIS_MODULE,
 		.of_match_table = ili9225_of_match,
 	},
 	.id_table = ili9225_id,
 	.probe = ili9225_probe,
 	.shutdown = ili9225_shutdown,
 };
 module_spi_driver(ili9225_spi_driver);

 MODULE_DESCRIPTION("Ilitek ILI9225 DRM driver");
 MODULE_AUTHOR("David Lechner <david@lechnology.com>");
 MODULE_LICENSE("GPL");
	/*
	* DRM driver for Ilitek ILI9225 panels
	*
	* Copyright 2017 David Lechner <david@lechnology.com>
	*
	* Some code copied from mipi-dbi.c
	* Copyright 2016 Noralf Trønnes
	*
	* 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.
	*/

	#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_fb_helper.h>
	#include <drm/drm_gem_framebuffer_helper.h>
	#include <drm/tinydrm/mipi-dbi.h>
	#include <drm/tinydrm/tinydrm-helpers.h>

	#define ILI9225_DRIVER_READ_CODE 0x00
	#define ILI9225_DRIVER_OUTPUT_CONTROL 0x01
	#define ILI9225_LCD_AC_DRIVING_CONTROL 0x02
	#define ILI9225_ENTRY_MODE 0x03
	#define ILI9225_DISPLAY_CONTROL_1 0x07
	#define ILI9225_BLANK_PERIOD_CONTROL_1 0x08
	#define ILI9225_FRAME_CYCLE_CONTROL 0x0b
	#define ILI9225_INTERFACE_CONTROL 0x0c
	#define ILI9225_OSCILLATION_CONTROL 0x0f
	#define ILI9225_POWER_CONTROL_1 0x10
	#define ILI9225_POWER_CONTROL_2 0x11
	#define ILI9225_POWER_CONTROL_3 0x12
	#define ILI9225_POWER_CONTROL_4 0x13
	#define ILI9225_POWER_CONTROL_5 0x14
	#define ILI9225_VCI_RECYCLING 0x15
	#define ILI9225_RAM_ADDRESS_SET_1 0x20
	#define ILI9225_RAM_ADDRESS_SET_2 0x21
	#define ILI9225_WRITE_DATA_TO_GRAM 0x22
	#define ILI9225_SOFTWARE_RESET 0x28
	#define ILI9225_GATE_SCAN_CONTROL 0x30
	#define ILI9225_VERTICAL_SCROLL_1 0x31
	#define ILI9225_VERTICAL_SCROLL_2 0x32
	#define ILI9225_VERTICAL_SCROLL_3 0x33
	#define ILI9225_PARTIAL_DRIVING_POS_1 0x34
	#define ILI9225_PARTIAL_DRIVING_POS_2 0x35
	#define ILI9225_HORIZ_WINDOW_ADDR_1 0x36
	#define ILI9225_HORIZ_WINDOW_ADDR_2 0x37
	#define ILI9225_VERT_WINDOW_ADDR_1 0x38
	#define ILI9225_VERT_WINDOW_ADDR_2 0x39
	#define ILI9225_GAMMA_CONTROL_1 0x50
	#define ILI9225_GAMMA_CONTROL_2 0x51
	#define ILI9225_GAMMA_CONTROL_3 0x52
	#define ILI9225_GAMMA_CONTROL_4 0x53
	#define ILI9225_GAMMA_CONTROL_5 0x54
	#define ILI9225_GAMMA_CONTROL_6 0x55
	#define ILI9225_GAMMA_CONTROL_7 0x56
	#define ILI9225_GAMMA_CONTROL_8 0x57
	#define ILI9225_GAMMA_CONTROL_9 0x58
	#define ILI9225_GAMMA_CONTROL_10 0x59

	static inline int ili9225_command(struct mipi_dbi *mipi, u8 cmd, u16 data)
	{
	u8 par[2] = { data >> 8, data & 0xff };

	return mipi_dbi_command_buf(mipi, cmd, par, 2);
	}

	static int ili9225_fb_dirty(struct drm_framebuffer *fb,
	struct drm_file *file_priv, unsigned int flags,
	unsigned int color, struct drm_clip_rect *clips,
	unsigned int num_clips)
	{
	struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
	struct tinydrm_device *tdev = fb->dev->dev_private;
	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
	bool swap = mipi->swap_bytes;
	struct drm_clip_rect clip;
	u16 x_start, y_start;
	u16 x1, x2, y1, y2;
	int ret = 0;
	bool full;
	void *tr;

	if (!mipi->enabled)
	return 0;

	full = tinydrm_merge_clips(&clip, clips, num_clips, flags,
	fb->width, fb->height);

	DRM_DEBUG("Flushing [FB:%d] x1=%u, x2=%u, y1=%u, y2=%u\n", fb->base.id,
	clip.x1, clip.x2, clip.y1, clip.y2);

	if (!mipi->dc \|\| !full \|\| swap \|\|
	fb->format->format == DRM_FORMAT_XRGB8888) {
	tr = mipi->tx_buf;
	ret = mipi_dbi_buf_copy(mipi->tx_buf, fb, &clip, swap);
	if (ret)
	return ret;
	} else {
	tr = cma_obj->vaddr;
	}

	switch (mipi->rotation) {
	default:
	x1 = clip.x1;
	x2 = clip.x2 - 1;
	y1 = clip.y1;
	y2 = clip.y2 - 1;
	x_start = x1;
	y_start = y1;
	break;
	case 90:
	x1 = clip.y1;
	x2 = clip.y2 - 1;
	y1 = fb->width - clip.x2;
	y2 = fb->width - clip.x1 - 1;
	x_start = x1;
	y_start = y2;
	break;
	case 180:
	x1 = fb->width - clip.x2;
	x2 = fb->width - clip.x1 - 1;
	y1 = fb->height - clip.y2;
	y2 = fb->height - clip.y1 - 1;
	x_start = x2;
	y_start = y2;
	break;
	case 270:
	x1 = fb->height - clip.y2;
	x2 = fb->height - clip.y1 - 1;
	y1 = clip.x1;
	y2 = clip.x2 - 1;
	x_start = x2;
	y_start = y1;
	break;
	}

	ili9225_command(mipi, ILI9225_HORIZ_WINDOW_ADDR_1, x2);
	ili9225_command(mipi, ILI9225_HORIZ_WINDOW_ADDR_2, x1);
	ili9225_command(mipi, ILI9225_VERT_WINDOW_ADDR_1, y2);
	ili9225_command(mipi, ILI9225_VERT_WINDOW_ADDR_2, y1);

	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_1, x_start);
	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_2, y_start);

	ret = mipi_dbi_command_buf(mipi, ILI9225_WRITE_DATA_TO_GRAM, tr,
	(clip.x2 - clip.x1) * (clip.y2 - clip.y1) * 2);

	return ret;
	}

	static const struct drm_framebuffer_funcs ili9225_fb_funcs = {
	.destroy = drm_gem_fb_destroy,
	.create_handle = drm_gem_fb_create_handle,
	.dirty = tinydrm_fb_dirty,
	};

	static void ili9225_pipe_enable(struct drm_simple_display_pipe *pipe,
	struct drm_crtc_state *crtc_state,
	struct drm_plane_state *plane_state)
	{
	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
	struct device *dev = tdev->drm->dev;
	int ret;
	u8 am_id;

	DRM_DEBUG_KMS("\n");

	mipi_dbi_hw_reset(mipi);

	/*
	* There don't seem to be two example init sequences that match, so
	* using the one from the popular Arduino library for this display.
	* https://github.com/Nkawu/TFT_22_ILI9225/blob/master/src/TFT_22_ILI9225.cpp
	*/

	ret = ili9225_command(mipi, ILI9225_POWER_CONTROL_1, 0x0000);
	if (ret) {
	DRM_DEV_ERROR(dev, "Error sending command %d\n", ret);
	return;
	}
	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x0000);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_3, 0x0000);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_4, 0x0000);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_5, 0x0000);

	msleep(40);

	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x0018);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_3, 0x6121);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_4, 0x006f);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_5, 0x495f);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_1, 0x0800);

	msleep(10);

	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x103b);

	msleep(50);

	switch (mipi->rotation) {
	default:
	am_id = 0x30;
	break;
	case 90:
	am_id = 0x18;
	break;
	case 180:
	am_id = 0x00;
	break;
	case 270:
	am_id = 0x28;
	break;
	}
	ili9225_command(mipi, ILI9225_DRIVER_OUTPUT_CONTROL, 0x011c);
	ili9225_command(mipi, ILI9225_LCD_AC_DRIVING_CONTROL, 0x0100);
	ili9225_command(mipi, ILI9225_ENTRY_MODE, 0x1000 \| am_id);
	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x0000);
	ili9225_command(mipi, ILI9225_BLANK_PERIOD_CONTROL_1, 0x0808);
	ili9225_command(mipi, ILI9225_FRAME_CYCLE_CONTROL, 0x1100);
	ili9225_command(mipi, ILI9225_INTERFACE_CONTROL, 0x0000);
	ili9225_command(mipi, ILI9225_OSCILLATION_CONTROL, 0x0d01);
	ili9225_command(mipi, ILI9225_VCI_RECYCLING, 0x0020);
	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_1, 0x0000);
	ili9225_command(mipi, ILI9225_RAM_ADDRESS_SET_2, 0x0000);

	ili9225_command(mipi, ILI9225_GATE_SCAN_CONTROL, 0x0000);
	ili9225_command(mipi, ILI9225_VERTICAL_SCROLL_1, 0x00db);
	ili9225_command(mipi, ILI9225_VERTICAL_SCROLL_2, 0x0000);
	ili9225_command(mipi, ILI9225_VERTICAL_SCROLL_3, 0x0000);
	ili9225_command(mipi, ILI9225_PARTIAL_DRIVING_POS_1, 0x00db);
	ili9225_command(mipi, ILI9225_PARTIAL_DRIVING_POS_2, 0x0000);

	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_1, 0x0000);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_2, 0x0808);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_3, 0x080a);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_4, 0x000a);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_5, 0x0a08);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_6, 0x0808);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_7, 0x0000);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_8, 0x0a00);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_9, 0x0710);
	ili9225_command(mipi, ILI9225_GAMMA_CONTROL_10, 0x0710);

	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x0012);

	msleep(50);

	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x1017);

	mipi_dbi_enable_flush(mipi, crtc_state, plane_state);
	}

	static void ili9225_pipe_disable(struct drm_simple_display_pipe *pipe)
	{
	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);

	DRM_DEBUG_KMS("\n");

	if (!mipi->enabled)
	return;

	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x0000);
	msleep(50);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_2, 0x0007);
	msleep(50);
	ili9225_command(mipi, ILI9225_POWER_CONTROL_1, 0x0a02);

	mipi->enabled = false;
	}

	static int ili9225_dbi_command(struct mipi_dbi mipi, u8 cmd, u8 *par,
	size_t num)
	{
	struct spi_device *spi = mipi->spi;
	unsigned int bpw = 8;
	u32 speed_hz;
	int ret;

	gpiod_set_value_cansleep(mipi->dc, 0);
	speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1);
	ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, cmd, 1);
	if (ret \|\| !num)
	return ret;

	if (*cmd == ILI9225_WRITE_DATA_TO_GRAM && !mipi->swap_bytes)
	bpw = 16;

	gpiod_set_value_cansleep(mipi->dc, 1);
	speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num);

	return tinydrm_spi_transfer(spi, speed_hz, NULL, bpw, par, num);
	}

	static const u32 ili9225_formats[] = {
	DRM_FORMAT_RGB565,
	DRM_FORMAT_XRGB8888,
	};

	static int ili9225_init(struct device dev, struct mipi_dbi mipi,
	const struct drm_simple_display_pipe_funcs *pipe_funcs,
	struct drm_driver *driver,
	const struct drm_display_mode *mode,
	unsigned int rotation)
	{
	size_t bufsize = mode->vdisplay * mode->hdisplay * sizeof(u16);
	struct tinydrm_device *tdev = &mipi->tinydrm;
	int ret;

	if (!mipi->command)
	return -EINVAL;

	mutex_init(&mipi->cmdlock);

	mipi->tx_buf = devm_kmalloc(dev, bufsize, GFP_KERNEL);
	if (!mipi->tx_buf)
	return -ENOMEM;

	ret = devm_tinydrm_init(dev, tdev, &ili9225_fb_funcs, driver);
	if (ret)
	return ret;

	tdev->fb_dirty = ili9225_fb_dirty;

	ret = tinydrm_display_pipe_init(tdev, pipe_funcs,
	DRM_MODE_CONNECTOR_VIRTUAL,
	ili9225_formats,
	ARRAY_SIZE(ili9225_formats), mode,
	rotation);
	if (ret)
	return ret;

	tdev->drm->mode_config.preferred_depth = 16;
	mipi->rotation = rotation;

	drm_mode_config_reset(tdev->drm);

	DRM_DEBUG_KMS("preferred_depth=%u, rotation = %u\n",
	tdev->drm->mode_config.preferred_depth, rotation);

	return 0;
	}

	static const struct drm_simple_display_pipe_funcs ili9225_pipe_funcs = {
	.enable = ili9225_pipe_enable,
	.disable = ili9225_pipe_disable,
	.update = tinydrm_display_pipe_update,
	.prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
	};

	static const struct drm_display_mode ili9225_mode = {
	TINYDRM_MODE(176, 220, 35, 44),
	};

	DEFINE_DRM_GEM_CMA_FOPS(ili9225_fops);

	static struct drm_driver ili9225_driver = {
	.driver_features = DRIVER_GEM \| DRIVER_MODESET \| DRIVER_PRIME \|
	DRIVER_ATOMIC,
	.fops = &ili9225_fops,
	TINYDRM_GEM_DRIVER_OPS,
	.name = "ili9225",
	.desc = "Ilitek ILI9225",
	.date = "20171106",
	.major = 1,
	.minor = 0,
	};

	static const struct of_device_id ili9225_of_match[] = {
	{ .compatible = "vot,v220hf01a-t" },
	{},
	};
	MODULE_DEVICE_TABLE(of, ili9225_of_match);

	static const struct spi_device_id ili9225_id[] = {
	{ "v220hf01a-t", 0 },
	{ },
	};
	MODULE_DEVICE_TABLE(spi, ili9225_id);

	static int ili9225_probe(struct spi_device *spi)
	{
	struct device *dev = &spi->dev;
	struct mipi_dbi *mipi;
	struct gpio_desc *rs;
	u32 rotation = 0;
	int ret;

	mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
	if (!mipi)
	return -ENOMEM;

	mipi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
	if (IS_ERR(mipi->reset)) {
	DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
	return PTR_ERR(mipi->reset);
	}

	rs = devm_gpiod_get(dev, "rs", GPIOD_OUT_LOW);
	if (IS_ERR(rs)) {
	DRM_DEV_ERROR(dev, "Failed to get gpio 'rs'\n");
	return PTR_ERR(rs);
	}

	device_property_read_u32(dev, "rotation", &rotation);

	ret = mipi_dbi_spi_init(spi, mipi, rs);
	if (ret)
	return ret;

	/* override the command function set in mipi_dbi_spi_init() */
	mipi->command = ili9225_dbi_command;

	ret = ili9225_init(&spi->dev, mipi, &ili9225_pipe_funcs,
	&ili9225_driver, &ili9225_mode, rotation);
	if (ret)
	return ret;

	spi_set_drvdata(spi, mipi);

	return devm_tinydrm_register(&mipi->tinydrm);
	}

	static void ili9225_shutdown(struct spi_device *spi)
	{
	struct mipi_dbi *mipi = spi_get_drvdata(spi);

	tinydrm_shutdown(&mipi->tinydrm);
	}

	static struct spi_driver ili9225_spi_driver = {
	.driver = {
	.name = "ili9225",
	.owner = THIS_MODULE,
	.of_match_table = ili9225_of_match,
	},
	.id_table = ili9225_id,
	.probe = ili9225_probe,
	.shutdown = ili9225_shutdown,
	};
	module_spi_driver(ili9225_spi_driver);

	MODULE_DESCRIPTION("Ilitek ILI9225 DRM driver");
	MODULE_AUTHOR("David Lechner <david@lechnology.com>");
	MODULE_LICENSE("GPL");