Commit e943da47 authored by Felix Brack's avatar Felix Brack Committed by Lee Jones
Browse files

backlight: otm3225a: Add support for ORISE OTM3225A LCD SoC 



This patch adds a LCD driver supporting the OTM3225A LCD SoC
from ORISE Technology. This device can drive TFT LC panels having a
resolution of 240x320 pixels. After initializing the OTM3225A using
it's SPI interface it switches to use 16-bib RGB as external
display interface.

Signed-off-by: default avatarFelix Brack <fb@ltec.ch>
Acked-by: default avatarDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
parent bb084c0f

drivers/video/backlight/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -150,6 +150,13 @@ config LCD_HX8357 
	  If you have a HX-8357 LCD panel, say Y to enable its LCD control

	  driver.



  config LCD_OTM3225A

  	tristate "ORISE Technology OTM3225A support"

  	depends on SPI

  	help

  	  If you have a panel based on the OTM3225A controller

  	  chip then say y to include a driver for it.



endif # LCD_CLASS_DEVICE



#

drivers/video/backlight/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ obj-$(CONFIG_LCD_LD9040) += ld9040.o 
obj-$(CONFIG_LCD_LMS283GF05)		+= lms283gf05.o

obj-$(CONFIG_LCD_LMS501KF03)		+= lms501kf03.o

obj-$(CONFIG_LCD_LTV350QV)		+= ltv350qv.o

obj-$(CONFIG_LCD_OTM3225A)		+= otm3225a.o

obj-$(CONFIG_LCD_PLATFORM)		+= platform_lcd.o

obj-$(CONFIG_LCD_S6E63M0)		+= s6e63m0.o

obj-$(CONFIG_LCD_TDO24M)		+= tdo24m.o

drivers/video/backlight/otm3225a.c

0 → 100644
+252 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Driver for ORISE Technology OTM3225A SOC for TFT LCD

 * Copyright (C) 2017, EETS GmbH, Felix Brack <fb@ltec.ch>

 *

 * This driver implements a lcd device for the ORISE OTM3225A display

 * controller. The control interface to the display is SPI and the display's

 * memory is updated over the 16-bit RGB interface.

 * The main source of information for writing this driver was provided by the

 * OTM3225A datasheet from ORISE Technology. Some information arise from the

 * ILI9328 datasheet from ILITEK as well as from the datasheets and sample code

 * provided by Crystalfontz America Inc. who sells the CFAF240320A-032T, a 3.2"

 * TFT LC display using the OTM3225A controller.

 */



#include <linux/delay.h>

#include <linux/device.h>

#include <linux/kernel.h>

#include <linux/lcd.h>

#include <linux/module.h>

#include <linux/spi/spi.h>



#define OTM3225A_INDEX_REG	0x70

#define OTM3225A_DATA_REG	0x72



/* instruction register list */

#define DRIVER_OUTPUT_CTRL_1	0x01

#define DRIVER_WAVEFORM_CTRL	0x02

#define ENTRY_MODE		0x03

#define SCALING_CTRL		0x04

#define DISPLAY_CTRL_1		0x07

#define DISPLAY_CTRL_2		0x08

#define DISPLAY_CTRL_3		0x09

#define FRAME_CYCLE_CTRL	0x0A

#define EXT_DISP_IFACE_CTRL_1	0x0C

#define FRAME_MAKER_POS		0x0D

#define EXT_DISP_IFACE_CTRL_2	0x0F

#define POWER_CTRL_1		0x10

#define POWER_CTRL_2		0x11

#define POWER_CTRL_3		0x12

#define POWER_CTRL_4		0x13

#define GRAM_ADDR_HORIZ_SET	0x20

#define GRAM_ADDR_VERT_SET	0x21

#define GRAM_READ_WRITE		0x22

#define POWER_CTRL_7		0x29

#define FRAME_RATE_CTRL		0x2B

#define GAMMA_CTRL_1		0x30

#define GAMMA_CTRL_2		0x31

#define GAMMA_CTRL_3		0x32

#define GAMMA_CTRL_4		0x35

#define GAMMA_CTRL_5		0x36

#define GAMMA_CTRL_6		0x37

#define GAMMA_CTRL_7		0x38

#define GAMMA_CTRL_8		0x39

#define GAMMA_CTRL_9		0x3C

#define GAMMA_CTRL_10		0x3D

#define WINDOW_HORIZ_RAM_START	0x50

#define WINDOW_HORIZ_RAM_END	0x51

#define WINDOW_VERT_RAM_START	0x52

#define WINDOW_VERT_RAM_END	0x53

#define DRIVER_OUTPUT_CTRL_2	0x60

#define BASE_IMG_DISPLAY_CTRL	0x61

#define VERT_SCROLL_CTRL	0x6A

#define PD1_DISPLAY_POS		0x80

#define PD1_RAM_START		0x81

#define PD1_RAM_END		0x82

#define PD2_DISPLAY_POS		0x83

#define PD2_RAM_START		0x84

#define PD2_RAM_END		0x85

#define PANEL_IFACE_CTRL_1	0x90

#define PANEL_IFACE_CTRL_2	0x92

#define PANEL_IFACE_CTRL_4	0x95

#define PANEL_IFACE_CTRL_5	0x97



struct otm3225a_data {

	struct spi_device *spi;

	struct lcd_device *ld;

	int power;

};



struct otm3225a_spi_instruction {

	unsigned char reg;	/* register to write */

	unsigned short value;	/* data to write to 'reg' */

	unsigned short delay;	/* delay in ms after write */

};



static struct otm3225a_spi_instruction display_init[] = {

	{ DRIVER_OUTPUT_CTRL_1,		0x0000, 0 },

	{ DRIVER_WAVEFORM_CTRL,		0x0700, 0 },

	{ ENTRY_MODE,			0x50A0, 0 },

	{ SCALING_CTRL,			0x0000, 0 },

	{ DISPLAY_CTRL_2,		0x0606, 0 },

	{ DISPLAY_CTRL_3,		0x0000, 0 },

	{ FRAME_CYCLE_CTRL,		0x0000, 0 },

	{ EXT_DISP_IFACE_CTRL_1,	0x0000, 0 },

	{ FRAME_MAKER_POS,		0x0000, 0 },

	{ EXT_DISP_IFACE_CTRL_2,	0x0002, 0 },

	{ POWER_CTRL_2,			0x0007, 0 },

	{ POWER_CTRL_3,			0x0000, 0 },

	{ POWER_CTRL_4,			0x0000, 200 },

	{ DISPLAY_CTRL_1,		0x0101, 0 },

	{ POWER_CTRL_1,			0x12B0, 0 },

	{ POWER_CTRL_2,			0x0007, 0 },

	{ POWER_CTRL_3,			0x01BB, 50 },

	{ POWER_CTRL_4,			0x0013, 0 },

	{ POWER_CTRL_7,			0x0010, 50 },

	{ GAMMA_CTRL_1,			0x000A, 0 },

	{ GAMMA_CTRL_2,			0x1326, 0 },

	{ GAMMA_CTRL_3,			0x0A29, 0 },

	{ GAMMA_CTRL_4,			0x0A0A, 0 },

	{ GAMMA_CTRL_5,			0x1E03, 0 },

	{ GAMMA_CTRL_6,			0x031E, 0 },

	{ GAMMA_CTRL_7,			0x0706, 0 },

	{ GAMMA_CTRL_8,			0x0303, 0 },

	{ GAMMA_CTRL_9,			0x010E, 0 },

	{ GAMMA_CTRL_10,		0x040E, 0 },

	{ WINDOW_HORIZ_RAM_START,	0x0000, 0 },

	{ WINDOW_HORIZ_RAM_END,		0x00EF, 0 },

	{ WINDOW_VERT_RAM_START,	0x0000, 0 },

	{ WINDOW_VERT_RAM_END,		0x013F, 0 },

	{ DRIVER_OUTPUT_CTRL_2,		0x2700, 0 },

	{ BASE_IMG_DISPLAY_CTRL,	0x0001, 0 },

	{ VERT_SCROLL_CTRL,		0x0000, 0 },

	{ PD1_DISPLAY_POS,		0x0000, 0 },

	{ PD1_RAM_START,		0x0000, 0 },

	{ PD1_RAM_END,			0x0000, 0 },

	{ PD2_DISPLAY_POS,		0x0000, 0 },

	{ PD2_RAM_START,		0x0000, 0 },

	{ PD2_RAM_END,			0x0000, 0 },

	{ PANEL_IFACE_CTRL_1,		0x0010, 0 },

	{ PANEL_IFACE_CTRL_2,		0x0000, 0 },

	{ PANEL_IFACE_CTRL_4,		0x0210, 0 },

	{ PANEL_IFACE_CTRL_5,		0x0000, 0 },

	{ DISPLAY_CTRL_1,		0x0133, 0 },

};



static struct otm3225a_spi_instruction display_enable_rgb_interface[] = {

	{ ENTRY_MODE,			0x1080, 0 },

	{ GRAM_ADDR_HORIZ_SET,		0x0000, 0 },

	{ GRAM_ADDR_VERT_SET,		0x0000, 0 },

	{ EXT_DISP_IFACE_CTRL_1,	0x0111, 500 },

};



static struct otm3225a_spi_instruction display_off[] = {

	{ DISPLAY_CTRL_1,	0x0131, 100 },

	{ DISPLAY_CTRL_1,	0x0130, 100 },

	{ DISPLAY_CTRL_1,	0x0100, 0 },

	{ POWER_CTRL_1,		0x0280, 0 },

	{ POWER_CTRL_3,		0x018B, 0 },

};



static struct otm3225a_spi_instruction display_on[] = {

	{ POWER_CTRL_1,		0x1280, 0 },

	{ DISPLAY_CTRL_1,	0x0101, 100 },

	{ DISPLAY_CTRL_1,	0x0121, 0 },

	{ DISPLAY_CTRL_1,	0x0123, 100 },

	{ DISPLAY_CTRL_1,	0x0133, 10 },

};



static void otm3225a_write(struct spi_device *spi,

			   struct otm3225a_spi_instruction *instruction,

			   unsigned int count)

{

	unsigned char buf[3];



	while (count--) {

		/* address register using index register */

		buf[0] = OTM3225A_INDEX_REG;

		buf[1] = 0x00;

		buf[2] = instruction->reg;

		spi_write(spi, buf, 3);



		/* write data to addressed register */

		buf[0] = OTM3225A_DATA_REG;

		buf[1] = (instruction->value >> 8) & 0xff;

		buf[2] = instruction->value & 0xff;

		spi_write(spi, buf, 3);



		/* execute delay if any */

		if (instruction->delay)

			msleep(instruction->delay);

		instruction++;

	}

}



static int otm3225a_set_power(struct lcd_device *ld, int power)

{

	struct otm3225a_data *dd = lcd_get_data(ld);



	if (power == dd->power)

		return 0;



	if (power > FB_BLANK_UNBLANK)

		otm3225a_write(dd->spi, display_off, ARRAY_SIZE(display_off));

	else

		otm3225a_write(dd->spi, display_on, ARRAY_SIZE(display_on));

	dd->power = power;



	return 0;

}



static int otm3225a_get_power(struct lcd_device *ld)

{

	struct otm3225a_data *dd = lcd_get_data(ld);



	return dd->power;

}



static struct lcd_ops otm3225a_ops = {

	.set_power = otm3225a_set_power,

	.get_power = otm3225a_get_power,

};



static int otm3225a_probe(struct spi_device *spi)

{

	struct otm3225a_data *dd;

	struct lcd_device *ld;

	struct device *dev = &spi->dev;



	dd = devm_kzalloc(dev, sizeof(struct otm3225a_data), GFP_KERNEL);

	if (dd == NULL)

		return -ENOMEM;



	ld = devm_lcd_device_register(dev, dev_name(dev), dev, dd,

				      &otm3225a_ops);

	if (IS_ERR(ld))

		return PTR_ERR(ld);



	dd->spi = spi;

	dd->ld = ld;

	dev_set_drvdata(dev, dd);



	dev_info(dev, "Initializing and switching to RGB interface");

	otm3225a_write(spi, display_init, ARRAY_SIZE(display_init));

	otm3225a_write(spi, display_enable_rgb_interface,

		       ARRAY_SIZE(display_enable_rgb_interface));

	return 0;

}



static struct spi_driver otm3225a_driver = {

	.driver = {

		.name = "otm3225a",

		.owner = THIS_MODULE,

	},

	.probe = otm3225a_probe,

};



module_spi_driver(otm3225a_driver);



MODULE_AUTHOR("Felix Brack <fb@ltec.ch>");

MODULE_DESCRIPTION("OTM3225A TFT LCD driver");

MODULE_VERSION("1.0.0");

MODULE_LICENSE("GPL v2");

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