lcd: add platform_lcd driver

Add a platform_lcd driver to allow boards with simple lcd power controls
to register themselves easily.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 180 insertions, 0 deletions

diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index a5b3a92ffdc1..b289e197e55d 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -53,6 +53,13 @@ config LCD_VGG2432A4
           If you have a VGG2432A4 panel based on the ILI9320 controller chip
           then say y to include a power driver for it.
 
+config LCD_PLATFORM
+        tristate "Platform LCD controls"
+        depends on LCD_CLASS_DEVICE
+        help
+          This driver provides a platform-device registered LCD power
+          control interface.
+
 #
 # Backlight
 #
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 366d84e380cf..7d31c14088aa 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -3,6 +3,7 @@
 obj-$(CONFIG_LCD_CLASS_DEVICE)     += lcd.o
 obj-$(CONFIG_LCD_LTV350QV)         += ltv350qv.o
 obj-$(CONFIG_LCD_ILI9320)          += ili9320.o
+obj-$(CONFIG_LCD_PLATFORM)         += platform_lcd.o
 obj-$(CONFIG_LCD_VGG2432A4)        += vgg2432a4.o
 
 obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
diff --git a/drivers/video/backlight/platform_lcd.c b/drivers/video/backlight/platform_lcd.c
new file mode 100644
index 000000000000..72d44dbfce82
--- /dev/null
+++ b/drivers/video/backlight/platform_lcd.c
@@ -0,0 +1,172 @@
+/* drivers/video/backlight/platform_lcd.c
+ *
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *
+ * Generic platform-device LCD power control interface.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+*/
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+#include <linux/lcd.h>
+
+#include <video/platform_lcd.h>
+
+struct platform_lcd {
+        struct device           *us;
+        struct lcd_device       *lcd;
+        struct plat_lcd_data    *pdata;
+
+        unsigned int             power;
+        unsigned int             suspended : 1;
+};
+
+static inline struct platform_lcd *to_our_lcd(struct lcd_device *lcd)
+{
+        return lcd_get_data(lcd);
+}
+
+static int platform_lcd_get_power(struct lcd_device *lcd)
+{
+        struct platform_lcd *plcd = to_our_lcd(lcd);
+
+        return plcd->power;
+}
+
+static int platform_lcd_set_power(struct lcd_device *lcd, int power)
+{
+        struct platform_lcd *plcd = to_our_lcd(lcd);
+        int lcd_power = 1;
+
+        if (power == FB_BLANK_POWERDOWN || plcd->suspended)
+                lcd_power = 0;
+
+        plcd->pdata->set_power(plcd->pdata, lcd_power);
+        plcd->power = power;
+
+        return 0;
+}
+
+static int platform_lcd_match(struct lcd_device *lcd, struct fb_info *info)
+{
+        struct platform_lcd *plcd = to_our_lcd(lcd);
+        struct plat_lcd_data *pdata = plcd->pdata;
+
+        if (pdata->match_fb)
+                return pdata->match_fb(pdata, info);
+
+        return plcd->us->parent == info->device;
+}
+
+static struct lcd_ops platform_lcd_ops = {
+        .get_power      = platform_lcd_get_power,
+        .set_power      = platform_lcd_set_power,
+        .check_fb       = platform_lcd_match,
+};
+
+static int __devinit platform_lcd_probe(struct platform_device *pdev)
+{
+        struct plat_lcd_data *pdata;
+        struct platform_lcd *plcd;
+        struct device *dev = &pdev->dev;
+        int err;
+
+        pdata = pdev->dev.platform_data;
+        if (!pdata) {
+                dev_err(dev, "no platform data supplied\n");
+                return -EINVAL;
+        }
+
+        plcd = kzalloc(sizeof(struct platform_lcd), GFP_KERNEL);
+        if (!plcd) {
+                dev_err(dev, "no memory for state\n");
+                return -ENOMEM;
+        }
+
+        plcd->us = dev;
+        plcd->pdata = pdata;
+        plcd->lcd = lcd_device_register("platform-lcd", dev,
+                                        plcd, &platform_lcd_ops);
+        if (IS_ERR(plcd->lcd)) {
+                dev_err(dev, "cannot register lcd device\n");
+                err = PTR_ERR(plcd->lcd);
+                goto err_mem;
+        }
+
+        platform_set_drvdata(pdev, plcd);
+        return 0;
+
+ err_mem:
+        kfree(plcd);
+        return err;
+}
+
+static int __devexit platform_lcd_remove(struct platform_device *pdev)
+{
+        struct platform_lcd *plcd = platform_get_drvdata(pdev);
+
+        lcd_device_unregister(plcd->lcd);
+        kfree(plcd);
+
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int platform_lcd_suspend(struct platform_device *pdev, pm_message_t st)
+{
+        struct platform_lcd *plcd = platform_get_drvdata(pdev);
+
+        plcd->suspended = 1;
+        platform_lcd_set_power(plcd->lcd, plcd->power);
+
+        return 0;
+}
+
+static int platform_lcd_resume(struct platform_device *pdev)
+{
+        struct platform_lcd *plcd = platform_get_drvdata(pdev);
+
+        plcd->suspended = 0;
+        platform_lcd_set_power(plcd->lcd, plcd->power);
+
+        return 0;
+}
+#else
+#define platform_lcd_suspend NULL
+#define platform_lcd_resume NULL
+#endif
+
+static struct platform_driver platform_lcd_driver = {
+        .driver         = {
+                .name   = "platform-lcd",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = platform_lcd_probe,
+        .remove         = __devexit_p(platform_lcd_remove),
+        .suspend        = platform_lcd_suspend,
+        .resume         = platform_lcd_resume,
+};
+
+static int __init platform_lcd_init(void)
+{
+        return platform_driver_register(&platform_lcd_driver);
+}
+
+static void __exit platform_lcd_cleanup(void)
+{
+        platform_driver_unregister(&platform_lcd_driver);
+}
+
+module_init(platform_lcd_init);
+module_exit(platform_lcd_cleanup);
+
+MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:platform-lcd");