Subject: [PATCH] s3c-fb: Add support ld9040 amoled panel driver

From: [email-masked] (Marek Szyprowski)
Date: Thu, 09 Sep 2010 15:46:06 +0900

Hello,

On 2010-09-09 11:16, Donghwa Lee wrote:

> This patch supports ld9040 amoled panel driver.
> It is similar to s6e63m0 panel driver and use spi gpio
> to send panel information.

You should remove the "s3c-fb" prefix from the patch subject, as the 
s3c-fb driver has nothing to LD9040 driver. Please use something generic 
like 'drivers: lcd:' or so.

> Signed-off-by: Donghwa Lee<[email-masked]>
> Signed-off-by: Inki Dae<[email-masked]>
> ---
>   drivers/video/backlight/Kconfig  |    7 +
>   drivers/video/backlight/Makefile |    1 +
>   drivers/video/backlight/ld9040.c |  687 ++++++++++++++++++++++++++++++++++++++
>   3 files changed, 695 insertions(+), 0 deletions(-)
>   create mode 100644 drivers/video/backlight/ld9040.c
>
> diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
> index e54a337..b8381d0 100644
> --- a/drivers/video/backlight/Kconfig
> +++ b/drivers/video/backlight/Kconfig
> @@ -109,6 +109,13 @@ config LCD_S6E63M0
>   	  If you have an S6E63M0 LCD Panel, say Y to enable its
>   	  LCD control driver.
>
> +config LCD_LD9040
> +	bool "LD9040 AMOLED LCD Driver"
> +	depends on SPI&&  BACKLIGHT_CLASS_DEVICE
> +	help
> +	  If you have an LD9040 LCD Panel, say Y to enable its
> +	  LCD control driver.
> +
>   endif # LCD_CLASS_DEVICE
>
>   #
> diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
> index 44c0f81..a52248e 100644
> --- a/drivers/video/backlight/Makefile
> +++ b/drivers/video/backlight/Makefile
> @@ -12,6 +12,7 @@ obj-$(CONFIG_LCD_VGG2432A4)	   += vgg2432a4.o
>   obj-$(CONFIG_LCD_TDO24M)	   += tdo24m.o
>   obj-$(CONFIG_LCD_TOSA)		   += tosa_lcd.o
>   obj-$(CONFIG_LCD_S6E63M0)	+= s6e63m0.o
> +obj-$(CONFIG_LCD_S6E63M0)	+= ld9040.o

You should use the newly defined LCD_LD9040 option in Makefile instead 
of hijacking the CONFIG_LCD_S6E63M0.

>
>   obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
>   obj-$(CONFIG_BACKLIGHT_ATMEL_PWM)    += atmel-pwm-bl.o
> diff --git a/drivers/video/backlight/ld9040.c b/drivers/video/backlight/ld9040.c
> new file mode 100644
> index 0000000..7a2109f
> --- /dev/null
> +++ b/drivers/video/backlight/ld9040.c
> @@ -0,0 +1,687 @@
> +/*
> + * ld9040 AMOLED LCD panel driver.
> + *
> + * Author: Donghwa Lee<[email-masked]>
> + *
> + * Derived from drivers/video/omap/lcd-apollon.c
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, write to the Free Software Foundation, Inc.,
> + * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
> + */
> +
> +#include<linux/wait.h>
> +#include<linux/fb.h>
> +#include<linux/delay.h>
> +#include<linux/gpio.h>
> +#include<linux/spi/spi.h>
> +#include<linux/irq.h>
> +#include<linux/interrupt.h>
> +#include<linux/kernel.h>
> +#include<linux/lcd.h>
> +#include<linux/backlight.h>
> +
> +#define SLEEPMSEC		0x1000
> +#define ENDDEF			0x2000
> +#define	DEFMASK			0xFF00
> +#define COMMAND_ONLY		0xFE
> +#define DATA_ONLY		0xFF
> +
> +#define POWER_IS_ON(pwr)	((pwr)<= FB_BLANK_NORMAL)
> +
> +struct ld9040 {
> +	struct device			*dev;
> +	struct spi_device		*spi;
> +	unsigned int			power;
> +	struct lcd_device		*ld;
> +	struct lcd_platform_data	*lcd_pd;
> +};
> +
> +static const unsigned short SEQ_SWRESET[] = {
> +	0x01, COMMAND_ONLY,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_USER_SETTING[] = {
> +	0xF0, 0x5A,
> +
> +	DATA_ONLY, 0x5A,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_ELVSS[] = {
> +	0xB1, 0x0B,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x16,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_GTCON[] = {
> +	0xF7, 0x09,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_GAMMA_SET1[] = {
> +	0xF9, 0x18,
> +
> +	DATA_ONLY, 0x9A,
> +	DATA_ONLY, 0xB0,
> +	DATA_ONLY, 0xAB,
> +	DATA_ONLY, 0xC4,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0xAA,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0xA1,
> +	DATA_ONLY, 0xB5,
> +	DATA_ONLY, 0xB0,
> +	DATA_ONLY, 0xC7,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0xC5,
> +	DATA_ONLY, 0x24,
> +	DATA_ONLY, 0xA7,
> +	DATA_ONLY, 0xAC,
> +	DATA_ONLY, 0x9A,
> +	DATA_ONLY, 0xB6,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0xE5,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_GAMMA_CTRL[] = {
> +	0xFB, 0x00,
> +
> +	DATA_ONLY, 0x5A,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_APON[] = {
> +	0xF3, 0x00,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x0A,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_DISPCTL[] = {
> +	0xF2, 0x02,
> +
> +	DATA_ONLY, 0x03,
> +	DATA_ONLY, 0x1C,
> +	DATA_ONLY, 0x10,
> +	DATA_ONLY, 0x10,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_SLPOUT[] = {
> +	0x11, COMMAND_ONLY,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_SLPIN[] = {
> +	0x10, COMMAND_ONLY,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_DISPON[] = {
> +	0x29, COMMAND_ONLY,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_DISPOFF[] = {
> +	0x28, COMMAND_ONLY,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VCI1_1ST_EN[] = {
> +	0xF3, 0x10,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VL1_EN[] = {
> +	0xF3, 0x11,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VL2_EN[] = {
> +	0xF3, 0x13,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VCI1_2ND_EN[] = {
> +	0xF3, 0x33,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VL3_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VREG1_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0x01,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VGH_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0x11,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VGL_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0x31,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x02,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VMOS_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xB1,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VINT_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xF1,
> +	/* DATA_ONLY, 0x71,	VMOS/VBL/VBH not used */
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	/* DATA_ONLY, 0x02,	VMOS/VBL/VBH not used */
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VBH_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xF9,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_VBL_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xFD,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_GAM_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xFF,
> +	/* DATA_ONLY, 0x73,	VMOS/VBL/VBH not used */
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	/* DATA_ONLY, 0x02,	VMOS/VBL/VBH not used */
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_SD_AMP_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xFF,
> +	/* DATA_ONLY, 0x73,	VMOS/VBL/VBH not used */
> +	DATA_ONLY, 0x80,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	/* DATA_ONLY, 0x02,	VMOS/VBL/VBH not used */
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_GLS_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xFF,
> +	/* DATA_ONLY, 0x73,	VMOS/VBL/VBH not used */
> +	DATA_ONLY, 0x81,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	/* DATA_ONLY, 0x02,	VMOS/VBL/VBH not used */
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_ELS_EN[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xFF,
> +	/* DATA_ONLY, 0x73,	VMOS/VBL/VBH not used */
> +	DATA_ONLY, 0x83,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	/* DATA_ONLY, 0x02,	VMOS/VBL/VBH not used */
> +	ENDDEF, 0x00
> +};
> +
> +static const unsigned short SEQ_EL_ON[] = {
> +	0xF3, 0x37,
> +
> +	DATA_ONLY, 0xFF,
> +	/* DATA_ONLY, 0x73,	VMOS/VBL/VBH not used */
> +	DATA_ONLY, 0x87,
> +	DATA_ONLY, 0x00,
> +	DATA_ONLY, 0x03,
> +	/* DATA_ONLY, 0x02,	VMOS/VBL/VBH not used */
> +	ENDDEF, 0x00
> +};
> +
> +static int ld9040_spi_write_byte(struct ld9040 *lcd, int addr, int data)
> +{
> +	u16 buf[1];
> +	struct spi_message msg;
> +
> +	struct spi_transfer xfer = {
> +		.len		= 2,
> +		.tx_buf		= buf,
> +	};
> +
> +	buf[0] = (addr<<  8) | data;
> +
> +	spi_message_init(&msg);
> +	spi_message_add_tail(&xfer,&msg);
> +
> +	return spi_sync(lcd->spi,&msg);
> +}
> +
> +static int ld9040_spi_write(struct ld9040 *lcd, unsigned char address,
> +	unsigned char command)
> +{
> +	int ret = 0;
> +
> +	if (address != DATA_ONLY)
> +		ret = ld9040_spi_write_byte(lcd, 0x0, address);
> +	if (command != COMMAND_ONLY)
> +		ret = ld9040_spi_write_byte(lcd, 0x1, command);
> +
> +	return ret;
> +}
> +
> +static int ld9040_panel_send_sequence(struct ld9040 *lcd,
> +	const unsigned short *wbuf)
> +{
> +	int ret = 0, i = 0;
> +
> +	while ((wbuf[i]&  DEFMASK) != ENDDEF) {
> +		if ((wbuf[i]&  DEFMASK) != SLEEPMSEC) {
> +			ret = ld9040_spi_write(lcd, wbuf[i], wbuf[i+1]);
> +			if (ret)
> +				break;
> +		} else
> +			udelay(wbuf[i+1]*1000);
> +		i += 2;
> +	}
> +
> +	return ret;
> +}
> +
> +static int ld9040_ldi_init(struct ld9040 *lcd)
> +{
> +	int ret, i;
> +	const unsigned short *init_seq[] = {
> +		SEQ_USER_SETTING,
> +		SEQ_ELVSS,
> +		SEQ_GTCON,
> +		SEQ_GAMMA_SET1,
> +		SEQ_GAMMA_CTRL,
> +		SEQ_SLPOUT,
> +	};
> +
> +	for (i = 0; i<  ARRAY_SIZE(init_seq); i++) {
> +		ret = ld9040_panel_send_sequence(lcd, init_seq[i]);
> +		mdelay(5);
> +		if (ret)
> +			break;
> +	}
> +
> +	return ret;
> +}
> +
> +static int ld9040_ldi_enable(struct ld9040 *lcd)
> +{
> +	int ret = 0;
> +
> +	ret = ld9040_panel_send_sequence(lcd, SEQ_DISPON);
> +
> +	return ret;
> +}
> +
> +static int ld9040_ldi_disable(struct ld9040 *lcd)
> +{
> +	int ret;
> +
> +	ret = ld9040_panel_send_sequence(lcd, SEQ_DISPOFF);
> +
> +	return ret;
> +}
> +
> +static int ld9040_power_on(struct ld9040 *lcd)
> +{
> +	int ret = 0;
> +	struct lcd_platform_data *pd = NULL;
> +	pd = lcd->lcd_pd;
> +	if (!pd) {
> +		dev_err(lcd->dev, "platform data is NULL.\n");
> +		return -EFAULT;
> +	}
> +
> +	if (!pd->power_on) {
> +		dev_err(lcd->dev, "power_on is NULL.\n");
> +		return -EFAULT;
> +	} else {
> +		pd->power_on(lcd->ld, 1);
> +		mdelay(pd->power_on_delay);
> +	}
> +
> +	if (!pd->reset) {
> +		dev_err(lcd->dev, "reset is NULL.\n");
> +		return -EFAULT;
> +	} else {
> +		pd->reset(lcd->ld);
> +		mdelay(pd->reset_delay);
> +	}
> +
> +	ret = ld9040_ldi_init(lcd);
> +	if (ret) {
> +		dev_err(lcd->dev, "failed to initialize ldi.\n");
> +		return ret;
> +	}
> +
> +	ret = ld9040_ldi_enable(lcd);
> +	if (ret) {
> +		dev_err(lcd->dev, "failed to enable ldi.\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ld9040_power_off(struct ld9040 *lcd)
> +{
> +	int ret = 0;
> +	struct lcd_platform_data *pd = NULL;
> +
> +	pd = lcd->lcd_pd;
> +	if (!pd) {
> +		dev_err(lcd->dev, "platform data is NULL.\n");
> +		return -EFAULT;
> +	}
> +
> +	ret = ld9040_ldi_disable(lcd);
> +	if (ret) {
> +		dev_err(lcd->dev, "lcd setting failed.\n");
> +		return -EIO;
> +	}
> +
> +	mdelay(pd->power_off_delay);
> +
> +	if (!pd->power_on) {
> +		dev_err(lcd->dev, "power_on is NULL.\n");
> +		return -EFAULT;
> +	} else
> +		pd->power_on(lcd->ld, 0);
> +
> +	return 0;
> +}
> +
> +static int ld9040_power(struct ld9040 *lcd, int power)
> +{
> +	int ret = 0;
> +
> +	if (POWER_IS_ON(power)&&  !POWER_IS_ON(lcd->power))
> +		ret = ld9040_power_on(lcd);
> +	else if (!POWER_IS_ON(power)&&  POWER_IS_ON(lcd->power))
> +		ret = ld9040_power_off(lcd);
> +
> +	if (!ret)
> +		lcd->power = power;
> +
> +	return ret;
> +}
> +
> +static int ld9040_set_power(struct lcd_device *ld, int power)
> +{
> +	struct ld9040 *lcd = lcd_get_data(ld);
> +
> +	if (power != FB_BLANK_UNBLANK&&  power != FB_BLANK_POWERDOWN&&
> +		power != FB_BLANK_NORMAL) {
> +		dev_err(lcd->dev, "power value should be 0, 1 or 4.\n");
> +		return -EINVAL;
> +	}
> +
> +	return ld9040_power(lcd, power);
> +}
> +
> +static int ld9040_get_power(struct lcd_device *ld)
> +{
> +	struct ld9040 *lcd = lcd_get_data(ld);
> +
> +	return lcd->power;
> +}
> +
> +static struct lcd_ops ld9040_lcd_ops = {
> +	.set_power = ld9040_set_power,
> +	.get_power = ld9040_get_power,
> +};
> +
> +
> +static int __init ld9040_probe(struct spi_device *spi)
> +{
> +	int ret = 0;
> +	struct ld9040 *lcd = NULL;
> +	struct lcd_device *ld = NULL;
> +
> +	lcd = kzalloc(sizeof(struct ld9040), GFP_KERNEL);
> +	if (!lcd)
> +		return -ENOMEM;
> +
> +	/* ld9040 lcd panel uses 3-wire 9bits SPI Mode. */
> +	spi->bits_per_word = 9;
> +
> +	ret = spi_setup(spi);
> +	if (ret<  0) {
> +		dev_err(&spi->dev, "spi setup failed.\n");
> +		goto out_free_lcd;
> +	}
> +
> +	lcd->spi = spi;
> +	lcd->dev =&spi->dev;
> +
> +	lcd->lcd_pd = (struct lcd_platform_data *)spi->dev.platform_data;
> +	if (!lcd->lcd_pd) {
> +		dev_err(&spi->dev, "platform data is NULL.\n");
> +		goto out_free_lcd;
> +	}
> +
> +	ld = lcd_device_register("ld9040",&spi->dev, lcd,&ld9040_lcd_ops);

Please be a bit more consistent in the coding style. There should be a 
space after a comma. This applies to the above line and the few other.

> +	if (IS_ERR(ld)) {
> +		ret = PTR_ERR(ld);
> +		goto out_free_lcd;
> +	}
> +
> +	lcd->ld = ld;
> +
> +	/*
> +	 * if lcd panel was on from bootloader like u-boot then
> +	 * do not lcd on.
> +	 */
> +	if (!lcd->lcd_pd->lcd_enabled) {
> +		/*
> +		 * if lcd panel was off from bootloader then
> +		 * current lcd status is powerdown and then
> +		 * it enables lcd panel.
> +		 */
> +		lcd->power = FB_BLANK_POWERDOWN;
> +
> +		ld9040_power(lcd, FB_BLANK_UNBLANK);
> +	} else
> +		lcd->power = FB_BLANK_UNBLANK;
> +
> +	dev_set_drvdata(&spi->dev, lcd);
> +
> +	dev_info(&spi->dev, "ld9040 panel driver has been probed.\n");
> +	return 0;
> +
> +out_free_lcd:
> +	kfree(lcd);
> +	return ret;
> +}
> +
> +static int __devexit ld9040_remove(struct spi_device *spi)
> +{
> +	struct ld9040 *lcd = dev_get_drvdata(&spi->dev);
> +
> +	ld9040_power(lcd, FB_BLANK_POWERDOWN);
> +	lcd_device_unregister(lcd->ld);
> +	kfree(lcd);
> +
> +	return 0;
> +}
> +
> +#if defined(CONFIG_PM)
> +unsigned int beforepower;
> +
> +static int ld9040_suspend(struct spi_device *spi, pm_message_t mesg)
> +{
> +	int ret = 0;
> +	struct ld9040 *lcd = dev_get_drvdata(&spi->dev);
> +
> +	dev_dbg(&spi->dev, "lcd->power = %d\n", lcd->power);
> +
> +	beforepower = lcd->power;
> +
> +	/*
> +	 * when lcd panel is suspend, lcd panel becomes off
> +	 * regardless of status.
> +	 */
> +	ret = ld9040_power(lcd, FB_BLANK_POWERDOWN);
> +
> +	return ret;
> +}
> +
> +static int ld9040_resume(struct spi_device *spi)
> +{
> +	int ret = 0;
> +	struct ld9040 *lcd = dev_get_drvdata(&spi->dev);
> +
> +	/*
> +	 * after suspended, if lcd panel status is FB_BLANK_UNBLANK
> +	 * (at that time, power is FB_BLANK_UNBLANK) then
> +	 * it changes that status to FB_BLANK_POWERDOWN to get lcd on.
> +	 */
> +	if (beforepower == FB_BLANK_UNBLANK)
> +		lcd->power = FB_BLANK_POWERDOWN;
> +
> +	dev_dbg(&spi->dev, "power = %d\n", beforepower);
> +
> +	ret = ld9040_power(lcd, beforepower);
> +
> +	return ret;
> +}
> +#else
> +#define ld9040_suspend		NULL
> +#define ld9040_resume		NULL
> +#endif
> +
> +/* Power down all displays on reboot, poweroff or halt. */
> +static void ld9040_shutdown(struct spi_device *spi)
> +{
> +	struct ld9040 *lcd = dev_get_drvdata(&spi->dev);
> +
> +	ld9040_power(lcd, FB_BLANK_POWERDOWN);
> +}
> +
> +static struct spi_driver ld9040_driver = {
> +	.driver = {
> +		.name	= "ld9040",
> +		.bus	=&spi_bus_type,
> +		.owner	= THIS_MODULE,
> +	},
> +	.probe		= ld9040_probe,
> +	.remove		= __devexit_p(ld9040_remove),
> +	.shutdown	= ld9040_shutdown,
> +	.suspend	= ld9040_suspend,
> +	.resume		= ld9040_resume,
> +};
> +
> +static int __init ld9040_init(void)
> +{
> +	return spi_register_driver(&ld9040_driver);
> +}
> +
> +static void __exit ld9040_exit(void)
> +{
> +	spi_unregister_driver(&ld9040_driver);
> +}
> +
> +module_init(ld9040_init);
> +module_exit(ld9040_exit);
> +
> +MODULE_AUTHOR("Donghwa Lee<[email-masked]>");
> +MODULE_DESCRIPTION("ld9040 LCD Driver");
> +MODULE_LICENSE("GPL");
> +

Best regards
-- 
Marek Szyprowski
Samsung Poland R&D Center