diff options
Diffstat (limited to 'target/linux/ubicom32/files/drivers/video/backlight/ubicom32lcdpower.c')
| -rw-r--r-- | target/linux/ubicom32/files/drivers/video/backlight/ubicom32lcdpower.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/target/linux/ubicom32/files/drivers/video/backlight/ubicom32lcdpower.c b/target/linux/ubicom32/files/drivers/video/backlight/ubicom32lcdpower.c new file mode 100644 index 000000000..6aeed43bc --- /dev/null +++ b/target/linux/ubicom32/files/drivers/video/backlight/ubicom32lcdpower.c @@ -0,0 +1,194 @@ +/* + * drivers/video/backlight/ubicom32lcdpowerpower.c + * LCD power driver for the Ubicom32 platform + * + * (C) Copyright 2009, Ubicom, Inc. + * + * This file is part of the Ubicom32 Linux Kernel Port. + * + * The Ubicom32 Linux Kernel Port 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. + * + * The Ubicom32 Linux Kernel Port 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 the Ubicom32 Linux Kernel Port. If not, + * see <http://www.gnu.org/licenses/>. + * + * Ubicom32 implementation derived from (with many thanks): + * arch/m68knommu + * arch/blackfin + * arch/parisc + */ +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/lcd.h> +#include <linux/fb.h> +#include <linux/gpio.h> + +#include <asm/ubicom32lcdpower.h> +#include <asm/ip5000.h> + +#define DRIVER_NAME "ubicom32lcdpower" + +struct ubicom32lcdpower_data { + /* + * Pointer to the platform data structure. Keep this around since we need values + * from it to set the backlight intensity. + */ + const struct ubicom32lcdpower_platform_data *pdata; + + /* + * LCD device, we have to save this for use when we remove ourselves. + */ + struct lcd_device *lcddev; +}; + +/* + * ubicom32lcdpower_set_power + */ +static int ubicom32lcdpower_set_power(struct lcd_device *ld, int power) +{ + struct ubicom32lcdpower_data *ud = (struct ubicom32lcdpower_data *)lcd_get_data(ld); + if (power == FB_BLANK_UNBLANK) { + gpio_direction_output(ud->pdata->vgh_gpio, ud->pdata->vgh_polarity); + return 0; + } + + gpio_direction_output(ud->pdata->vgh_gpio, !ud->pdata->vgh_polarity); + return 0; +} + +/* + * ubicom32lcdpower_get_power + */ +static int ubicom32lcdpower_get_power(struct lcd_device *ld) +{ + struct ubicom32lcdpower_data *ud = (struct ubicom32lcdpower_data *)lcd_get_data(ld); + int vgh = gpio_get_value(ud->pdata->vgh_gpio); + if ((vgh && ud->pdata->vgh_polarity) || (!vgh && !ud->pdata->vgh_polarity)) { + return 1; + } + + return 0; +} + +static struct lcd_ops ubicom32lcdpower_ops = { + .get_power = ubicom32lcdpower_get_power, + .set_power = ubicom32lcdpower_set_power, +}; + +/* + * ubicom32lcdpower_probe + */ +static int ubicom32lcdpower_probe(struct platform_device *pdev) +{ + const struct ubicom32lcdpower_platform_data *pdata = pdev->dev.platform_data; + struct ubicom32lcdpower_data *ud; + struct lcd_device *lcddev; + int retval; + + /* + * Check to see if we have any platform data, if we don't have a LCD to control + */ + if (!pdata) { + return -ENODEV; + } + + /* + * Allocate our private data + */ + ud = kzalloc(sizeof(struct ubicom32lcdpower_data), GFP_KERNEL); + if (!ud) { + return -ENOMEM; + } + + ud->pdata = pdata; + + /* + * Request our GPIOs + */ + retval = gpio_request(pdata->vgh_gpio, "vgh"); + if (retval) { + dev_err(&pdev->dev, "Failed to allocate vgh GPIO\n"); + goto fail_gpio; + } + + /* + * Register our lcd device + */ + lcddev = lcd_device_register(DRIVER_NAME, &pdev->dev, ud, &ubicom32lcdpower_ops); + if (IS_ERR(lcddev)) { + retval = PTR_ERR(lcddev); + goto fail; + } + + ud->lcddev = lcddev; + platform_set_drvdata(pdev, ud); + + ubicom32lcdpower_set_power(lcddev, FB_BLANK_UNBLANK); + + printk(KERN_INFO DRIVER_NAME ": LCD driver started\n"); + + return 0; + +fail: + gpio_free(pdata->vgh_gpio); + +fail_gpio: + platform_set_drvdata(pdev, NULL); + kfree(ud); + return retval; +} + +/* + * ubicom32lcdpower_remove + */ +static int __exit ubicom32lcdpower_remove(struct platform_device *pdev) +{ + struct ubicom32lcdpower_data *ud = platform_get_drvdata(pdev); + + lcd_device_unregister(ud->lcddev); + platform_set_drvdata(pdev, NULL); + kfree(ud); + + return 0; +} + +static struct platform_driver ubicom32lcdpower_driver = { + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, + + .remove = __exit_p(ubicom32lcdpower_remove), +}; + +/* + * ubicom32lcdpower_init + */ +static int __init ubicom32lcdpower_init(void) +{ + return platform_driver_probe(&ubicom32lcdpower_driver, ubicom32lcdpower_probe); +} +module_init(ubicom32lcdpower_init); + +/* + * ubicom32lcdpower_exit + */ +static void __exit ubicom32lcdpower_exit(void) +{ + platform_driver_unregister(&ubicom32lcdpower_driver); +} +module_exit(ubicom32lcdpower_exit); + +MODULE_AUTHOR("Patrick Tjin <@ubicom.com>"); +MODULE_DESCRIPTION("Ubicom32 lcd power driver"); +MODULE_LICENSE("GPL"); |