From baf5f6c4f4ec0caf5240b452b75eeab2f96d8bd4 Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Sat, 24 Apr 2010 12:20:56 +0200 Subject: [PATCH] Add gpm940b0 lcd driver --- drivers/video/backlight/Kconfig | 7 + drivers/video/backlight/Makefile | 1 + drivers/video/backlight/gpm940b0.c | 253 ++++++++++++++++++++++++++++++++++++ 3 files changed, 261 insertions(+), 0 deletions(-) create mode 100644 drivers/video/backlight/gpm940b0.c diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index c025c84..0a61f91 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -107,6 +107,13 @@ config LCD_HP700 If you have an HP Jornada 700 series handheld (710/720/728) say Y to enable LCD control driver. +config LCD_GPM940B0 + tristate "Giantplus GPM940B0 LCD and backlight driver" + depends on LCD_CLASS_DEVICE && SPI + default n + help + LCD and backlight driver for the Giantplus GPM940B0 LCD module. + # # Backlight # diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 09d1f14..a03ec9c 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_LCD_PLATFORM) += platform_lcd.o obj-$(CONFIG_LCD_VGG2432A4) += vgg2432a4.o obj-$(CONFIG_LCD_TDO24M) += tdo24m.o obj-$(CONFIG_LCD_TOSA) += tosa_lcd.o +obj-$(CONFIG_LCD_GPM940B0) += gpm940b0.o obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o obj-$(CONFIG_BACKLIGHT_ATMEL_PWM) += atmel-pwm-bl.o diff --git a/drivers/video/backlight/gpm940b0.c b/drivers/video/backlight/gpm940b0.c new file mode 100644 index 0000000..879e3ad --- /dev/null +++ b/drivers/video/backlight/gpm940b0.c @@ -0,0 +1,253 @@ +/* + * Copyright (C) 2009-2010, Lars-Peter Clausen + * Driver for Giantplus GPM940B0 LCD + * + * 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. + * + * 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., + * 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + +#include +#include +#include +#include +#include + +struct gpm940b0 { + struct spi_device *spi; + struct lcd_device *lcd; + struct backlight_device *bl; + unsigned enabled:1; +}; + +static int gpm940b0_write_reg(struct spi_device *spi, uint8_t reg, + uint8_t data) +{ + uint8_t buf[2]; + buf[0] = ((reg & 0x40) << 1) | (reg & 0x3f); + buf[1] = data; + + return spi_write(spi, buf, sizeof(buf)); +} + +static void gpm940b0_power_disable(struct spi_device *spi) +{ + int ret = gpm940b0_write_reg(spi, 0x5, 0xc6) ; + if (ret < 0) + dev_err(&spi->dev, "Failed to disable power: %d\n", ret); +} + +static void gpm940b0_power_enable(struct spi_device *spi) +{ + gpm940b0_write_reg(spi, 0x5, 0xc7); +} + + +static int gpm940b0_set_power(struct lcd_device *lcd, int power) +{ + struct gpm940b0 *gpm940b0 = lcd_get_data(lcd); + + switch (power) { + case FB_BLANK_UNBLANK: + mdelay(20); + gpm940b0->enabled = 1; + gpm940b0_power_enable(gpm940b0->spi); + break; + default: + gpm940b0->enabled = 0; + gpm940b0_power_disable(gpm940b0->spi); + mdelay(20); + break; + } + return 0; +} + +static int gpm940b0_set_contrast(struct lcd_device *lcd, int contrast) +{ + struct gpm940b0 *gpm940b0 = lcd_get_data(lcd); + gpm940b0_write_reg(gpm940b0->spi, 0x0d, contrast); + return 0; +} + +static int gpm940b0_set_mode(struct lcd_device *lcd, struct fb_videomode *mode) +{ + if (mode->xres != 320 && mode->yres != 240) + return -EINVAL; + + return 0; +} + +static ssize_t reg_write(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + char *buf2; + uint32_t reg = simple_strtoul(buf, &buf2, 10); + uint32_t val = simple_strtoul(buf2 + 1, NULL, 10); + struct gpm940b0 *gpm940b0 = dev_get_drvdata(dev); + + if (reg < 0 || val < 0) + return -EINVAL; + + gpm940b0_write_reg(gpm940b0->spi, reg, val); + return count; +} + +static DEVICE_ATTR(reg, 0644, NULL, reg_write); + +static ssize_t gpm940b0_show_brightness(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int rc = -ENXIO; + + return rc; +} + +static ssize_t gpm940b0_store_brightness(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + char *endp; + struct lcd_device *ld = to_lcd_device(dev); + struct gpm940b0 *gpm940b0 = lcd_get_data(ld); + int brightness = simple_strtoul(buf, &endp, 0); + + if (brightness > 255 || brightness < 0) + return -EINVAL; + + gpm940b0_write_reg(gpm940b0->spi, 0x3, brightness); + + return count; +} + + +static DEVICE_ATTR(brightness, 0644, gpm940b0_show_brightness, + gpm940b0_store_brightness); + +static struct lcd_ops gpm940b0_lcd_ops = { + .set_power = gpm940b0_set_power, + .set_contrast = gpm940b0_set_contrast, + .set_mode = gpm940b0_set_mode, +}; + +static int __devinit gpm940b0_probe(struct spi_device *spi) +{ + int ret; + struct gpm940b0 *gpm940b0; + + gpm940b0 = kmalloc(sizeof(*gpm940b0), GFP_KERNEL); + + spi->bits_per_word = 8; + spi->mode = SPI_MODE_3 | SPI_3WIRE; + + ret = spi_setup(spi); + if (ret) { + dev_err(&spi->dev, "Failed to setup spi\n"); + goto err_free_gpm940b0; + } + + gpm940b0->spi = spi; + + gpm940b0->lcd = lcd_device_register("gpm940b0-lcd", &spi->dev, gpm940b0, + &gpm940b0_lcd_ops); + + if (IS_ERR(gpm940b0->lcd)) { + ret = PTR_ERR(gpm940b0->lcd); + dev_err(&spi->dev, "Failed to register lcd device: %d\n", ret); + goto err_free_gpm940b0; + } + + gpm940b0->lcd->props.max_contrast = 255; + + ret = device_create_file(&spi->dev, &dev_attr_reg); + if (ret) + goto err_unregister_lcd; + + ret = device_create_file(&gpm940b0->lcd->dev, &dev_attr_brightness); + if (ret) + goto err_unregister_lcd; + + gpm940b0->enabled = 1; + dev_set_drvdata(&spi->dev, gpm940b0); + + gpm940b0_write_reg(spi, 0x13, 0x01); + gpm940b0_write_reg(spi, 0x5, 0xc7); + return 0; +err_unregister_lcd: + lcd_device_unregister(gpm940b0->lcd); +err_free_gpm940b0: + kfree(gpm940b0); + return ret; +} + +static int __devexit gpm940b0_remove(struct spi_device *spi) +{ + struct gpm940b0 *gpm940b0 = spi_get_drvdata(spi); +#if 0 + if (gpm940b0->bl) + backlight_device_unregister(gpm940b0->bl); +#endif + + lcd_device_unregister(gpm940b0->lcd); + + spi_set_drvdata(spi, NULL); + kfree(gpm940b0); + return 0; +} + +#ifdef CONFIG_PM + +static int gpm940b0_suspend(struct spi_device *spi, pm_message_t state) +{ + struct gpm940b0 *gpm940b0 = spi_get_drvdata(spi); + if (gpm940b0->enabled) { + gpm940b0_power_disable(spi); + mdelay(10); + } + return 0; +} + +static int gpm940b0_resume(struct spi_device *spi) +{ + struct gpm940b0 *gpm940b0 = spi_get_drvdata(spi); + if (gpm940b0->enabled) + gpm940b0_power_enable(spi); + return 0; +} + +#else +#define gpm940b0_suspend NULL +#define gpm940b0_resume NULL +#endif + +static struct spi_driver gpm940b0_driver = { + .driver = { + .name = "gpm940b0", + .owner = THIS_MODULE, + }, + .probe = gpm940b0_probe, + .remove = __devexit_p(gpm940b0_remove), + .suspend = gpm940b0_suspend, + .resume = gpm940b0_resume, +}; + +static int __init gpm940b0_init(void) +{ + return spi_register_driver(&gpm940b0_driver); +} +module_init(gpm940b0_init); + +static void __exit gpm940b0_exit(void) +{ + return spi_unregister_driver(&gpm940b0_driver); +} +module_exit(gpm940b0_exit) + +MODULE_AUTHOR("Lars-Peter Clausen"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("LCD and backlight controll for Giantplus GPM940B0"); +MODULE_ALIAS("spi:gpm940b0"); -- 1.5.6.5