Re: [PATCH v2] backlight: otm3225a: add support for ORISE OTM3225A LCD SoC
From: Felix Brack
Date: Wed Mar 14 2018 - 10:41:39 EST
Hello,
On 27.12.2017 16:20, Felix Brack wrote:
> 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: Felix Brack <fb@xxxxxxx>
>
> Changes in v2:
> - use descriptive names for registers instead of hard coding them
> - remove unnecessary registers in initialization sequence
> - make use of resource-managed functions like devm_kzalloc()
> instead of kzalloc() which simplifies and shortens the code
> - replace mdelay() by msleep()
> - use module_spi_init() since we do not do anything special
> in init/exit
> - use dev_name() instead of hard coding driver name multiple times
> - use static storage class for structure otm3225a_ops
> - sort include files alphabetically
> - use standardized licensing header
> - modify Makefile respecting alphabetical sort order
> ---
> drivers/video/backlight/Kconfig | 7 ++
> drivers/video/backlight/Makefile | 1 +
> drivers/video/backlight/otm3225a.c | 251 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 259 insertions(+)
> create mode 100644 drivers/video/backlight/otm3225a.c
>
> diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
> index 4e1d2ad..06e187b 100644
> --- a/drivers/video/backlight/Kconfig
> +++ b/drivers/video/backlight/Kconfig
> @@ -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
>
> #
> diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
> index 8905129..2473377 100644
> --- a/drivers/video/backlight/Makefile
> +++ b/drivers/video/backlight/Makefile
> @@ -12,6 +12,7 @@ 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
> diff --git a/drivers/video/backlight/otm3225a.c b/drivers/video/backlight/otm3225a.c
> new file mode 100644
> index 0000000..cb1df6c
> --- /dev/null
> +++ b/drivers/video/backlight/otm3225a.c
> @@ -0,0 +1,251 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Driver for ORISE Technology OTM3225A SOC for TFT LCD
> + * Copyright (C) 2017, EETS GmbH, Felix Brack <fb@xxxxxxx>
> + *
> + * 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
> +
> +/* instruncton 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 */
> + 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@xxxxxxx>");
> +MODULE_DESCRIPTION("OTM3225A TFT LCD driver");
> +MODULE_VERSION("1.0.0");
> +MODULE_LICENSE("GPL v2");
>
Just a gentle echo request: This patch was sent and Acked more then two
months ago. Is there anything preventing it from being queued for a
future kernel release?
regards, Felix