2017-12-20 17:58:59

by Felix Brack

[permalink] [raw]
Subject: [PATCH] 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: Felix Brack <[email protected]>
---
drivers/video/backlight/Kconfig | 7 ++
drivers/video/backlight/Makefile | 1 +
drivers/video/backlight/otm3225a.c | 210 +++++++++++++++++++++++++++++++++++++
3 files changed, 218 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..b177b91 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_LCD_S6E63M0) += s6e63m0.o
obj-$(CONFIG_LCD_TDO24M) += tdo24m.o
obj-$(CONFIG_LCD_TOSA) += tosa_lcd.o
obj-$(CONFIG_LCD_VGG2432A4) += vgg2432a4.o
+obj-$(CONFIG_LCD_OTM3225A) += otm3225a.o

obj-$(CONFIG_BACKLIGHT_88PM860X) += 88pm860x_bl.o
obj-$(CONFIG_BACKLIGHT_AAT2870) += aat2870_bl.o
diff --git a/drivers/video/backlight/otm3225a.c b/drivers/video/backlight/otm3225a.c
new file mode 100644
index 0000000..0de75f8
--- /dev/null
+++ b/drivers/video/backlight/otm3225a.c
@@ -0,0 +1,210 @@
+/*
+ * Driver for ORISE Technology OTM3225A SOC for TFT LCD
+ *
+ * Copyright (C) 2014-2017, EETS GmbH, Felix Brack <[email protected]>
+ *
+ * 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.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+
+ * 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/device.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/lcd.h>
+#include <linux/spi/spi.h>
+
+#define OTM3225A_INDEX_REG 0x70
+#define OTM3225A_DATA_REG 0x72
+
+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[] = {
+ { 0x01, 0x0000, 0 }, { 0x02, 0x0700, 0 }, { 0x03, 0x50A0, 0 },
+ { 0x04, 0x0000, 0 }, { 0x08, 0x0606, 0 }, { 0x09, 0x0000, 0 },
+ { 0x0A, 0x0000, 0 }, { 0x0C, 0x0000, 0 }, { 0x0D, 0x0000, 0 },
+ { 0x0F, 0x0002, 0 }, { 0x11, 0x0007, 0 }, { 0x12, 0x0000, 0 },
+ { 0x13, 0x0000, 200 }, { 0x07, 0x0101, 0 }, { 0x10, 0x12B0, 0 },
+ { 0x11, 0x0007, 0 }, { 0x12, 0x01BB, 50 }, { 0xB1, 0x0000, 0 },
+ { 0xB3, 0x0000, 0 }, { 0xB5, 0x0000, 0 }, { 0xBE, 0x0000, 0 },
+ { 0x13, 0x0013, 0 }, { 0x29, 0x0010, 50 }, { 0x30, 0x000A, 0 },
+ { 0x31, 0x1326, 0 }, { 0x32, 0x0A29, 0 }, { 0x35, 0x0A0A, 0 },
+ { 0x36, 0x1E03, 0 }, { 0x37, 0x031E, 0 }, { 0x38, 0x0706, 0 },
+ { 0x39, 0x0303, 0 }, { 0x3C, 0x010E, 0 }, { 0x3D, 0x040E, 0 },
+ { 0x50, 0x0000, 0 }, { 0x51, 0x00EF, 0 }, { 0x52, 0x0000, 0 },
+ { 0x53, 0x013F, 0 }, { 0x60, 0x2700, 0 }, { 0x61, 0x0001, 0 },
+ { 0x6A, 0x0000, 0 }, { 0x80, 0x0000, 0 }, { 0x81, 0x0000, 0 },
+ { 0x82, 0x0000, 0 }, { 0x83, 0x0000, 0 }, { 0x84, 0x0000, 0 },
+ { 0x85, 0x0000, 0 }, { 0x90, 0x0010, 0 }, { 0x92, 0x0000, 0 },
+ { 0x93, 0x0103, 0 }, { 0x95, 0x0210, 0 }, { 0x97, 0x0000, 0 },
+ { 0x98, 0x0000, 0 }, { 0x07, 0x0133, 0 },
+};
+
+static struct otm3225a_spi_instruction display_enable_rgb_interface[] = {
+ { 0x03, 0x1080, 0 },
+ { 0x20, 0x0000, 0 },
+ { 0x21, 0x0000, 0 },
+ { 0x0C, 0x0111, 500 },
+};
+
+static struct otm3225a_spi_instruction display_off[] = {
+ { 0x07, 0x0131, 100 },
+ { 0x07, 0x0130, 100 },
+ { 0x07, 0x0100, 0 },
+ { 0x10, 0x0280, 0 },
+ { 0x12, 0x018B, 0 },
+};
+
+static struct otm3225a_spi_instruction display_on[] = {
+ { 0x10, 0x1280, 0 },
+ { 0x07, 0x0101, 100 },
+ { 0x07, 0x0121, 0 },
+ { 0x07, 0x0123, 100 },
+ { 0x07, 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 */
+ mdelay(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;
+}
+
+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;
+ int ret = 0;
+
+ dd = kzalloc(sizeof(struct otm3225a_data), GFP_KERNEL);
+ if (dd == NULL) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ld = lcd_device_register("otm3225a", &spi->dev, dd, &otm3225a_ops);
+ if (IS_ERR(ld)) {
+ ret = PTR_ERR(ld);
+ goto err;
+ }
+ dd->spi = spi;
+ dd->ld = ld;
+ dev_set_drvdata(&spi->dev, dd);
+
+ dev_info(&spi->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));
+
+err:
+ return ret;
+}
+
+static int otm3225a_remove(struct spi_device *spi)
+{
+ struct otm3225a_data *dd;
+
+ dd = dev_get_drvdata(&spi->dev);
+ lcd_device_unregister(dd->ld);
+ kfree(dd);
+ return 0;
+}
+
+static struct spi_driver otm3225a_driver = {
+ .driver = {
+ .name = "otm3225a",
+ .owner = THIS_MODULE,
+ },
+ .probe = otm3225a_probe,
+ .remove = otm3225a_remove,
+};
+
+static __init int otm3225a_init(void)
+{
+ return spi_register_driver(&otm3225a_driver);
+}
+
+static __exit void otm3225a_exit(void)
+{
+ spi_unregister_driver(&otm3225a_driver);
+}
+
+module_init(otm3225a_init);
+module_exit(otm3225a_exit);
+
+MODULE_AUTHOR("Felix Brack <[email protected]>");
+MODULE_DESCRIPTION("OTM3225A TFT LCD driver");
+MODULE_VERSION("1.0.0");
+MODULE_LICENSE("GPL v2");
--
2.7.4


2017-12-22 17:23:13

by Jingoo Han

[permalink] [raw]
Subject: Re: [PATCH] backlight: otm3225a: add support for ORISE OTM3225A LCD SoC

On Wednesday, December 20, 2017 12:58 PM, 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 <[email protected]>
> ---
> drivers/video/backlight/Kconfig | 7 ++
> drivers/video/backlight/Makefile | 1 +
> drivers/video/backlight/otm3225a.c | 210
> +++++++++++++++++++++++++++++++++++++
> 3 files changed, 218 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..b177b91 100644
> --- a/drivers/video/backlight/Makefile
> +++ b/drivers/video/backlight/Makefile
> @@ -17,6 +17,7 @@ obj-$(CONFIG_LCD_S6E63M0) += s6e63m0.o
> obj-$(CONFIG_LCD_TDO24M) += tdo24m.o
> obj-$(CONFIG_LCD_TOSA) += tosa_lcd.o
> obj-$(CONFIG_LCD_VGG2432A4) += vgg2432a4.o
> +obj-$(CONFIG_LCD_OTM3225A) += otm3225a.o

All entries of Kconfig was alphasorted 4 years ago for reducing
patch collisions. So please add it in alphabetical order as below.

@@ -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-$(CONFIG_BACKLIGHT_88PM860X) += 88pm860x_bl.o
> obj-$(CONFIG_BACKLIGHT_AAT2870) += aat2870_bl.o
> diff --git a/drivers/video/backlight/otm3225a.c
> b/drivers/video/backlight/otm3225a.c
> new file mode 100644
> index 0000000..0de75f8
> --- /dev/null
> +++ b/drivers/video/backlight/otm3225a.c
> @@ -0,0 +1,210 @@
> +/*
> + * Driver for ORISE Technology OTM3225A SOC for TFT LCD
> + *
> + * Copyright (C) 2014-2017, EETS GmbH, Felix Brack <[email protected]>

Please change the year of copyright as below.

+ * Copyright (C) 2017, EETS GmbH, Felix Brack <[email protected]>

> + *
> + * 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.
> +
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> +
> + * 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/device.h>
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/delay.h>
> +#include <linux/lcd.h>
> +#include <linux/spi/spi.h>

So please add these headers in alphabetical order
for readability.

> +
> +#define OTM3225A_INDEX_REG 0x70
> +#define OTM3225A_DATA_REG 0x72
> +
> +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[] = {
> + { 0x01, 0x0000, 0 }, { 0x02, 0x0700, 0 }, { 0x03, 0x50A0, 0 },
> + { 0x04, 0x0000, 0 }, { 0x08, 0x0606, 0 }, { 0x09, 0x0000, 0 },
> + { 0x0A, 0x0000, 0 }, { 0x0C, 0x0000, 0 }, { 0x0D, 0x0000, 0 },
> + { 0x0F, 0x0002, 0 }, { 0x11, 0x0007, 0 }, { 0x12, 0x0000, 0 },
> + { 0x13, 0x0000, 200 }, { 0x07, 0x0101, 0 }, { 0x10, 0x12B0, 0 },
> + { 0x11, 0x0007, 0 }, { 0x12, 0x01BB, 50 }, { 0xB1, 0x0000, 0 },
> + { 0xB3, 0x0000, 0 }, { 0xB5, 0x0000, 0 }, { 0xBE, 0x0000, 0 },
> + { 0x13, 0x0013, 0 }, { 0x29, 0x0010, 50 }, { 0x30, 0x000A, 0 },
> + { 0x31, 0x1326, 0 }, { 0x32, 0x0A29, 0 }, { 0x35, 0x0A0A, 0 },
> + { 0x36, 0x1E03, 0 }, { 0x37, 0x031E, 0 }, { 0x38, 0x0706, 0 },
> + { 0x39, 0x0303, 0 }, { 0x3C, 0x010E, 0 }, { 0x3D, 0x040E, 0 },
> + { 0x50, 0x0000, 0 }, { 0x51, 0x00EF, 0 }, { 0x52, 0x0000, 0 },
> + { 0x53, 0x013F, 0 }, { 0x60, 0x2700, 0 }, { 0x61, 0x0001, 0 },
> + { 0x6A, 0x0000, 0 }, { 0x80, 0x0000, 0 }, { 0x81, 0x0000, 0 },
> + { 0x82, 0x0000, 0 }, { 0x83, 0x0000, 0 }, { 0x84, 0x0000, 0 },
> + { 0x85, 0x0000, 0 }, { 0x90, 0x0010, 0 }, { 0x92, 0x0000, 0 },
> + { 0x93, 0x0103, 0 }, { 0x95, 0x0210, 0 }, { 0x97, 0x0000, 0 },
> + { 0x98, 0x0000, 0 }, { 0x07, 0x0133, 0 },
> +};
> +
> +static struct otm3225a_spi_instruction display_enable_rgb_interface[] = {
> + { 0x03, 0x1080, 0 },
> + { 0x20, 0x0000, 0 },
> + { 0x21, 0x0000, 0 },
> + { 0x0C, 0x0111, 500 },
> +};
> +
> +static struct otm3225a_spi_instruction display_off[] = {
> + { 0x07, 0x0131, 100 },
> + { 0x07, 0x0130, 100 },
> + { 0x07, 0x0100, 0 },
> + { 0x10, 0x0280, 0 },
> + { 0x12, 0x018B, 0 },
> +};
> +
> +static struct otm3225a_spi_instruction display_on[] = {
> + { 0x10, 0x1280, 0 },
> + { 0x07, 0x0101, 100 },
> + { 0x07, 0x0121, 0 },
> + { 0x07, 0x0123, 100 },
> + { 0x07, 0x0133, 10 },
> +};

Please change these hardcoded values into register define.
I found the datasheet of OTM3225A. I think you can change
the hardcoding for readability.
(https://www.crystalfontz.com/controllers/OriseTech/OTM3225A/196/)

For example, you can add register define and change display_on[]
as below.

#define DISPLAY_CONTROL_1 0x07
#define POWER_CONTROL_1 0x10

+static struct otm3225a_spi_instruction display_on[] = {
+ { POWER_CONTROL_1, 0x1280, 0 },
+ { DISPLAY_CONTROL_1, 0x0101, 100 },
+ { DISPLAY_CONTROL_1, 0x0121, 0 },
+ { DISPLAY_CONTROL_1, 0x0123, 100 },
+ { DISPLAY_CONTROL_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 */
> + mdelay(instruction->delay);

Please use msleep instead of mdelay.

> + 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;
> +}
> +
> +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;
> + int ret = 0;
> +
> + dd = kzalloc(sizeof(struct otm3225a_data), GFP_KERNEL);

Please use devm_kzalloc(), then you don't need to use kfree(dd)
in otm3225a_remove().

> + if (dd == NULL) {
> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + ld = lcd_device_register("otm3225a", &spi->dev, dd, &otm3225a_ops);

Please use devm_lcd_device_register(), then you don't need
to use lcd_device_unregister() in otm3225a_remove().

> + if (IS_ERR(ld)) {
> + ret = PTR_ERR(ld);
> + goto err;
> + }
> + dd->spi = spi;
> + dd->ld = ld;
> + dev_set_drvdata(&spi->dev, dd);
> +
> + dev_info(&spi->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));
> +
> +err:
> + return ret;
> +}
> +
> +static int otm3225a_remove(struct spi_device *spi)
> +{
> + struct otm3225a_data *dd;
> +
> + dd = dev_get_drvdata(&spi->dev);
> + lcd_device_unregister(dd->ld);
> + kfree(dd);

If you use devm_kzalloc() and devm_lcd_device_register()
in otm3225a_probe as I mentioned above, you can remove
lcd_device_unregister() and kfree() here.

If so, you don't need otm3225a_remove().
What I want to say is that you can add only probe() function
when you use devm_* functions in your otm3225a driver code.

> + return 0;
> +}
> +
> +static struct spi_driver otm3225a_driver = {
> + .driver = {
> + .name = "otm3225a",
> + .owner = THIS_MODULE,
> + },
> + .probe = otm3225a_probe,
> + .remove = otm3225a_remove,

If you use devm_kzalloc() and devm_lcd_device_register(),
you can remove otm3225a_remove() as below.

+static struct spi_driver otm3225a_driver = {
+ .driver = {
+ .name = "otm3225a",
+ .owner = THIS_MODULE,
+ },
+ .probe = otm3225a_probe,
+};

Please refer to the following driver.
./drivers/video/backlight/tps65217_bl.c

> +};
> +
> +static __init int otm3225a_init(void)
> +{
> + return (&otm3225a_driver);
> +}
> +
> +static __exit void otm3225a_exit(void)
> +{
> + spi_unregister_driver(&otm3225a_driver);
> +}
> +
> +module_init(otm3225a_init);
> +module_exit(otm3225a_exit);

Instead of adding otm3225a_init(), otm3225a_exit(),
please use module_spi_driver macro as below.
This macro can reduce source code lines.

module_spi_driver(otm3225a_driver);

Best regards,
Jingoo Han

> +
> +MODULE_AUTHOR("Felix Brack <[email protected]>");
> +MODULE_DESCRIPTION("OTM3225A TFT LCD driver");
> +MODULE_VERSION("1.0.0");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.4


2017-12-22 17:33:42

by Daniel Thompson

[permalink] [raw]
Subject: Re: [PATCH] backlight: otm3225a: add support for ORISE OTM3225A LCD SoC

On 22/12/17 17:23, Jingoo Han wrote:>> diff --git
a/drivers/video/backlight/otm3225a.c
>> b/drivers/video/backlight/otm3225a.c
>> new file mode 100644
>> index 0000000..0de75f8
>> --- /dev/null
>> +++ b/drivers/video/backlight/otm3225a.c
>> @@ -0,0 +1,210 @@
>> +/*
>> + * Driver for ORISE Technology OTM3225A SOC for TFT LCD
>> + *
>> + * Copyright (C) 2014-2017, EETS GmbH, Felix Brack <[email protected]>
>
> Please change the year of copyright as below. >
> + * Copyright (C) 2017, EETS GmbH, Felix Brack <[email protected]>

... and include (or just rely entirely on) a SPDX header to describe the
licensing of the file.


Daniel.

2017-12-22 22:11:50

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH] backlight: otm3225a: add support for ORISE OTM3225A LCD SoC

Hi Felix,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on backlight/for-backlight-next]
[also build test WARNING on v4.15-rc4 next-20171222]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url: https://github.com/0day-ci/linux/commits/Felix-Brack/backlight-otm3225a-add-support-for-ORISE-OTM3225A-LCD-SoC/20171223-042842
base: https://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight.git for-backlight-next
reproduce:
# apt-get install sparse
make ARCH=x86_64 allmodconfig
make C=1 CF=-D__CHECK_ENDIAN__


sparse warnings: (new ones prefixed by >>)


Please review and possibly fold the followup patch.

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation

2017-12-22 22:11:55

by kernel test robot

[permalink] [raw]
Subject: [RFC PATCH] backlight: otm3225a: otm3225a_ops can be static


Fixes: 640b353b5467 ("backlight: otm3225a: add support for ORISE OTM3225A LCD SoC")
Signed-off-by: Fengguang Wu <[email protected]>
---
otm3225a.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/backlight/otm3225a.c b/drivers/video/backlight/otm3225a.c
index 0de75f8..056ac8b 100644
--- a/drivers/video/backlight/otm3225a.c
+++ b/drivers/video/backlight/otm3225a.c
@@ -137,7 +137,7 @@ static int otm3225a_get_power(struct lcd_device *ld)
return dd->power;
}

-struct lcd_ops otm3225a_ops = {
+static struct lcd_ops otm3225a_ops = {
.set_power = otm3225a_set_power,
.get_power = otm3225a_get_power,
};

2017-12-27 10:16:32

by Felix Brack

[permalink] [raw]
Subject: Re: [PATCH] backlight: otm3225a: add support for ORISE OTM3225A LCD SoC

Hello Jingoo,

Many thanks for taking the time to review my patch! Your suggestions
will be implemented in v2 which I will post soon.

kind regards, Felix

On 22.12.2017 18:23, Jingoo Han wrote:
> On Wednesday, December 20, 2017 12:58 PM, 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 <[email protected]>
>> ---
>> drivers/video/backlight/Kconfig | 7 ++
>> drivers/video/backlight/Makefile | 1 +
>> drivers/video/backlight/otm3225a.c | 210
>> +++++++++++++++++++++++++++++++++++++
>> 3 files changed, 218 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..b177b91 100644
>> --- a/drivers/video/backlight/Makefile
>> +++ b/drivers/video/backlight/Makefile
>> @@ -17,6 +17,7 @@ obj-$(CONFIG_LCD_S6E63M0) += s6e63m0.o
>> obj-$(CONFIG_LCD_TDO24M) += tdo24m.o
>> obj-$(CONFIG_LCD_TOSA) += tosa_lcd.o
>> obj-$(CONFIG_LCD_VGG2432A4) += vgg2432a4.o
>> +obj-$(CONFIG_LCD_OTM3225A) += otm3225a.o
>
> All entries of Kconfig was alphasorted 4 years ago for reducing
> patch collisions. So please add it in alphabetical order as below.
>
> @@ -13,6 +13,7 @@ obj-$(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_BACKLIGHT_88PM860X) += 88pm860x_bl.o
>> obj-$(CONFIG_BACKLIGHT_AAT2870) += aat2870_bl.o
>> diff --git a/drivers/video/backlight/otm3225a.c
>> b/drivers/video/backlight/otm3225a.c
>> new file mode 100644
>> index 0000000..0de75f8
>> --- /dev/null
>> +++ b/drivers/video/backlight/otm3225a.c
>> @@ -0,0 +1,210 @@
>> +/*
>> + * Driver for ORISE Technology OTM3225A SOC for TFT LCD
>> + *
>> + * Copyright (C) 2014-2017, EETS GmbH, Felix Brack <[email protected]>
>
> Please change the year of copyright as below.
>
> + * Copyright (C) 2017, EETS GmbH, Felix Brack <[email protected]>
>
>> + *
>> + * 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.
>> +
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> +
>> + * 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/device.h>
>> +#include <linux/module.h>
>> +#include <linux/kernel.h>
>> +#include <linux/delay.h>
>> +#include <linux/lcd.h>
>> +#include <linux/spi/spi.h>
>
> So please add these headers in alphabetical order
> for readability.
>
>> +
>> +#define OTM3225A_INDEX_REG 0x70
>> +#define OTM3225A_DATA_REG 0x72
>> +
>> +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[] = {
>> + { 0x01, 0x0000, 0 }, { 0x02, 0x0700, 0 }, { 0x03, 0x50A0, 0 },
>> + { 0x04, 0x0000, 0 }, { 0x08, 0x0606, 0 }, { 0x09, 0x0000, 0 },
>> + { 0x0A, 0x0000, 0 }, { 0x0C, 0x0000, 0 }, { 0x0D, 0x0000, 0 },
>> + { 0x0F, 0x0002, 0 }, { 0x11, 0x0007, 0 }, { 0x12, 0x0000, 0 },
>> + { 0x13, 0x0000, 200 }, { 0x07, 0x0101, 0 }, { 0x10, 0x12B0, 0 },
>> + { 0x11, 0x0007, 0 }, { 0x12, 0x01BB, 50 }, { 0xB1, 0x0000, 0 },
>> + { 0xB3, 0x0000, 0 }, { 0xB5, 0x0000, 0 }, { 0xBE, 0x0000, 0 },
>> + { 0x13, 0x0013, 0 }, { 0x29, 0x0010, 50 }, { 0x30, 0x000A, 0 },
>> + { 0x31, 0x1326, 0 }, { 0x32, 0x0A29, 0 }, { 0x35, 0x0A0A, 0 },
>> + { 0x36, 0x1E03, 0 }, { 0x37, 0x031E, 0 }, { 0x38, 0x0706, 0 },
>> + { 0x39, 0x0303, 0 }, { 0x3C, 0x010E, 0 }, { 0x3D, 0x040E, 0 },
>> + { 0x50, 0x0000, 0 }, { 0x51, 0x00EF, 0 }, { 0x52, 0x0000, 0 },
>> + { 0x53, 0x013F, 0 }, { 0x60, 0x2700, 0 }, { 0x61, 0x0001, 0 },
>> + { 0x6A, 0x0000, 0 }, { 0x80, 0x0000, 0 }, { 0x81, 0x0000, 0 },
>> + { 0x82, 0x0000, 0 }, { 0x83, 0x0000, 0 }, { 0x84, 0x0000, 0 },
>> + { 0x85, 0x0000, 0 }, { 0x90, 0x0010, 0 }, { 0x92, 0x0000, 0 },
>> + { 0x93, 0x0103, 0 }, { 0x95, 0x0210, 0 }, { 0x97, 0x0000, 0 },
>> + { 0x98, 0x0000, 0 }, { 0x07, 0x0133, 0 },
>> +};
>> +
>> +static struct otm3225a_spi_instruction display_enable_rgb_interface[] = {
>> + { 0x03, 0x1080, 0 },
>> + { 0x20, 0x0000, 0 },
>> + { 0x21, 0x0000, 0 },
>> + { 0x0C, 0x0111, 500 },
>> +};
>> +
>> +static struct otm3225a_spi_instruction display_off[] = {
>> + { 0x07, 0x0131, 100 },
>> + { 0x07, 0x0130, 100 },
>> + { 0x07, 0x0100, 0 },
>> + { 0x10, 0x0280, 0 },
>> + { 0x12, 0x018B, 0 },
>> +};
>> +
>> +static struct otm3225a_spi_instruction display_on[] = {
>> + { 0x10, 0x1280, 0 },
>> + { 0x07, 0x0101, 100 },
>> + { 0x07, 0x0121, 0 },
>> + { 0x07, 0x0123, 100 },
>> + { 0x07, 0x0133, 10 },
>> +};
>
> Please change these hardcoded values into register define.
> I found the datasheet of OTM3225A. I think you can change
> the hardcoding for readability.
> (https://www.crystalfontz.com/controllers/OriseTech/OTM3225A/196/)
>
> For example, you can add register define and change display_on[]
> as below.
>
> #define DISPLAY_CONTROL_1 0x07
> #define POWER_CONTROL_1 0x10
>
> +static struct otm3225a_spi_instruction display_on[] = {
> + { POWER_CONTROL_1, 0x1280, 0 },
> + { DISPLAY_CONTROL_1, 0x0101, 100 },
> + { DISPLAY_CONTROL_1, 0x0121, 0 },
> + { DISPLAY_CONTROL_1, 0x0123, 100 },
> + { DISPLAY_CONTROL_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 */
>> + mdelay(instruction->delay);
>
> Please use msleep instead of mdelay.
>
>> + 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;
>> +}
>> +
>> +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;
>> + int ret = 0;
>> +
>> + dd = kzalloc(sizeof(struct otm3225a_data), GFP_KERNEL);
>
> Please use devm_kzalloc(), then you don't need to use kfree(dd)
> in otm3225a_remove().
>
>> + if (dd == NULL) {
>> + ret = -ENOMEM;
>> + goto err;
>> + }
>> +
>> + ld = lcd_device_register("otm3225a", &spi->dev, dd, &otm3225a_ops);
>
> Please use devm_lcd_device_register(), then you don't need
> to use lcd_device_unregister() in otm3225a_remove().
>
>> + if (IS_ERR(ld)) {
>> + ret = PTR_ERR(ld);
>> + goto err;
>> + }
>> + dd->spi = spi;
>> + dd->ld = ld;
>> + dev_set_drvdata(&spi->dev, dd);
>> +
>> + dev_info(&spi->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));
>> +
>> +err:
>> + return ret;
>> +}
>> +
>> +static int otm3225a_remove(struct spi_device *spi)
>> +{
>> + struct otm3225a_data *dd;
>> +
>> + dd = dev_get_drvdata(&spi->dev);
>> + lcd_device_unregister(dd->ld);
>> + kfree(dd);
>
> If you use devm_kzalloc() and devm_lcd_device_register()
> in otm3225a_probe as I mentioned above, you can remove
> lcd_device_unregister() and kfree() here.
>
> If so, you don't need otm3225a_remove().
> What I want to say is that you can add only probe() function
> when you use devm_* functions in your otm3225a driver code.
>
>> + return 0;
>> +}
>> +
>> +static struct spi_driver otm3225a_driver = {
>> + .driver = {
>> + .name = "otm3225a",
>> + .owner = THIS_MODULE,
>> + },
>> + .probe = otm3225a_probe,
>> + .remove = otm3225a_remove,
>
> If you use devm_kzalloc() and devm_lcd_device_register(),
> you can remove otm3225a_remove() as below.
>
> +static struct spi_driver otm3225a_driver = {
> + .driver = {
> + .name = "otm3225a",
> + .owner = THIS_MODULE,
> + },
> + .probe = otm3225a_probe,
> +};
>
> Please refer to the following driver.
> ./drivers/video/backlight/tps65217_bl.c
>
>> +};
>> +
>> +static __init int otm3225a_init(void)
>> +{
>> + return (&otm3225a_driver);
>> +}
>> +
>> +static __exit void otm3225a_exit(void)
>> +{
>> + spi_unregister_driver(&otm3225a_driver);
>> +}
>> +
>> +module_init(otm3225a_init);
>> +module_exit(otm3225a_exit);
>
> Instead of adding otm3225a_init(), otm3225a_exit(),
> please use module_spi_driver macro as below.
> This macro can reduce source code lines.
>
> module_spi_driver(otm3225a_driver);
>
> Best regards,
> Jingoo Han
>
>> +
>> +MODULE_AUTHOR("Felix Brack <[email protected]>");
>> +MODULE_DESCRIPTION("OTM3225A TFT LCD driver");
>> +MODULE_VERSION("1.0.0");
>> +MODULE_LICENSE("GPL v2");
>> --
>> 2.7.4
>
>

2017-12-27 10:23:25

by Felix Brack

[permalink] [raw]
Subject: Re: [PATCH] backlight: otm3225a: add support for ORISE OTM3225A LCD SoC

Hello Daniel,

On 22.12.2017 18:33, Daniel Thompson wrote:
> On 22/12/17 17:23, Jingoo Han wrote:>> diff --git
> a/drivers/video/backlight/otm3225a.c
>>> b/drivers/video/backlight/otm3225a.c
>>> new file mode 100644
>>> index 0000000..0de75f8
>>> --- /dev/null
>>> +++ b/drivers/video/backlight/otm3225a.c
>>> @@ -0,0 +1,210 @@
>>> +/*
>>> + * Driver for ORISE Technology OTM3225A SOC for TFT LCD
>>> + *
>>> + * Copyright (C) 2014-2017, EETS GmbH, Felix Brack <[email protected]>
>>
>> Please change the year of copyright as below. >
>> + * Copyright (C) 2017, EETS GmbH, Felix Brack <[email protected]>
>
> ... and include (or just rely entirely on) a SPDX header to describe the
> licensing of the file.
>
Thanks for the hint. I have opted for this first line in the source
file: "// SPDX-License-Identifier: GPL-2.0"
>
> Daniel.

kind regards, Felix