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/*
* Copyright (C) 2009, Lars-Peter Clausen <lars@metafoo.de>
* JZ4720/JZ4740 SoC LCD framebuffer driver
*
* 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 <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/lcd.h>
#include <linux/backlight.h>
#include <linux/delay.h>
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 gpm940b0 *gpm940b0)
{
int ret = gpm940b0_write_reg(gpm940b0->spi, 0x5, 0xc6) ;
if (ret < 0)
printk("Failed to disable power: %d\n", ret);
}
static void gpm940b0_power_enable(struct gpm940b0 *gpm940b0)
{
gpm940b0_write_reg(gpm940b0->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);
break;
default:
gpm940b0->enabled = 0;
gpm940b0_power_disable(gpm940b0);
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;
}
/*
int gpm940b0_bl_update_status(struct backlight_device *bl)
{
struct gpm940b0 *gpm940b0 = bl_get_data(bl);
gpm940b0->reg5 &= ~0x38;
gpm940b0->reg5 |= ((bl->props.brightness << 3) & 0x38);
gpm940b0_write_reg(gpm940b0->spi, 0x5, gpm940b0->reg5);
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 struct lcd_ops gpm940b0_lcd_ops = {
.set_power = gpm940b0_set_power,
.set_contrast = gpm940b0_set_contrast,
.set_mode = gpm940b0_set_mode,
};
#if 0
static struct backlight_ops gpm940b0_bl_ops = {
/* .get_brightness = gpm940b0_bl_get_brightness,*/
.update_status = gpm940b0_bl_update_status,
};
#endif
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;
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;
#if 0
gpm940b0->bl = backlight_device_register("gpm940b0-bl", &spi->dev, gpm940b0,
&gpm940b0_bl_ops);
if (IS_ERR(gpm940b0->bl)) {
ret = PTR_ERR(gpm940b0->bl);
dev_err(&spi->dev, "Failed to register backlight device: %d\n", ret);
gpm940b0->bl = NULL;
} else {
gpm940b0->bl->props.max_brightness = 8;
gpm940b0->bl->props.brightness = 0;
gpm940b0->bl->props.power = FB_BLANK_UNBLANK;
}
#endif
ret = device_create_file(&spi->dev, &dev_attr_reg);
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(gpm940b0);
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(gpm940b0);
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");
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