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path: root/drivers/video/backlight/corgi_bl.c
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Diffstat (limited to 'drivers/video/backlight/corgi_bl.c')
-rw-r--r--drivers/video/backlight/corgi_bl.c198
1 files changed, 198 insertions, 0 deletions
diff --git a/drivers/video/backlight/corgi_bl.c b/drivers/video/backlight/corgi_bl.c
new file mode 100644
index 000000000000..3c026b036c86
--- /dev/null
+++ b/drivers/video/backlight/corgi_bl.c
@@ -0,0 +1,198 @@
+/*
+ * Backlight Driver for Sharp Corgi
+ *
+ * Copyright (c) 2004-2005 Richard Purdie
+ *
+ * Based on Sharp's 2.4 Backlight Driver
+ *
+ * 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/kernel.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/spinlock.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+
+#include <asm/arch-pxa/corgi.h>
+#include <asm/hardware/scoop.h>
+
+#define CORGI_MAX_INTENSITY 0x3e
+#define CORGI_DEFAULT_INTENSITY 0x1f
+#define CORGI_LIMIT_MASK 0x0b
+
+static int corgibl_powermode = FB_BLANK_UNBLANK;
+static int current_intensity = 0;
+static int corgibl_limit = 0;
+static spinlock_t bl_lock = SPIN_LOCK_UNLOCKED;
+
+static void corgibl_send_intensity(int intensity)
+{
+ unsigned long flags;
+ void (*corgi_kick_batt)(void);
+
+ if (corgibl_powermode != FB_BLANK_UNBLANK) {
+ intensity = 0;
+ } else {
+ if (corgibl_limit)
+ intensity &= CORGI_LIMIT_MASK;
+ }
+
+ /* Skip 0x20 as it will blank the display */
+ if (intensity >= 0x20)
+ intensity++;
+
+ spin_lock_irqsave(&bl_lock, flags);
+ /* Bits 0-4 are accessed via the SSP interface */
+ corgi_ssp_blduty_set(intensity & 0x1f);
+ /* Bit 5 is via SCOOP */
+ if (intensity & 0x0020)
+ set_scoop_gpio(&corgiscoop_device.dev, CORGI_SCP_BACKLIGHT_CONT);
+ else
+ reset_scoop_gpio(&corgiscoop_device.dev, CORGI_SCP_BACKLIGHT_CONT);
+ spin_unlock_irqrestore(&bl_lock, flags);
+}
+
+static void corgibl_blank(int blank)
+{
+ switch(blank) {
+
+ case FB_BLANK_NORMAL:
+ case FB_BLANK_VSYNC_SUSPEND:
+ case FB_BLANK_HSYNC_SUSPEND:
+ case FB_BLANK_POWERDOWN:
+ if (corgibl_powermode == FB_BLANK_UNBLANK) {
+ corgibl_send_intensity(0);
+ corgibl_powermode = blank;
+ }
+ break;
+ case FB_BLANK_UNBLANK:
+ if (corgibl_powermode != FB_BLANK_UNBLANK) {
+ corgibl_powermode = blank;
+ corgibl_send_intensity(current_intensity);
+ }
+ break;
+ }
+}
+
+#ifdef CONFIG_PM
+static int corgibl_suspend(struct device *dev, u32 state, u32 level)
+{
+ if (level == SUSPEND_POWER_DOWN)
+ corgibl_blank(FB_BLANK_POWERDOWN);
+ return 0;
+}
+
+static int corgibl_resume(struct device *dev, u32 level)
+{
+ if (level == RESUME_POWER_ON)
+ corgibl_blank(FB_BLANK_UNBLANK);
+ return 0;
+}
+#else
+#define corgibl_suspend NULL
+#define corgibl_resume NULL
+#endif
+
+
+static int corgibl_set_power(struct backlight_device *bd, int state)
+{
+ corgibl_blank(state);
+ return 0;
+}
+
+static int corgibl_get_power(struct backlight_device *bd)
+{
+ return corgibl_powermode;
+}
+
+static int corgibl_set_intensity(struct backlight_device *bd, int intensity)
+{
+ if (intensity > CORGI_MAX_INTENSITY)
+ intensity = CORGI_MAX_INTENSITY;
+ corgibl_send_intensity(intensity);
+ current_intensity=intensity;
+ return 0;
+}
+
+static int corgibl_get_intensity(struct backlight_device *bd)
+{
+ return current_intensity;
+}
+
+/*
+ * Called when the battery is low to limit the backlight intensity.
+ * If limit==0 clear any limit, otherwise limit the intensity
+ */
+void corgibl_limit_intensity(int limit)
+{
+ corgibl_limit = (limit ? 1 : 0);
+ corgibl_send_intensity(current_intensity);
+}
+EXPORT_SYMBOL(corgibl_limit_intensity);
+
+
+static struct backlight_properties corgibl_data = {
+ .owner = THIS_MODULE,
+ .get_power = corgibl_get_power,
+ .set_power = corgibl_set_power,
+ .max_brightness = CORGI_MAX_INTENSITY,
+ .get_brightness = corgibl_get_intensity,
+ .set_brightness = corgibl_set_intensity,
+};
+
+static struct backlight_device *corgi_backlight_device;
+
+static int __init corgibl_probe(struct device *dev)
+{
+ corgi_backlight_device = backlight_device_register ("corgi-bl",
+ NULL, &corgibl_data);
+ if (IS_ERR (corgi_backlight_device))
+ return PTR_ERR (corgi_backlight_device);
+
+ corgibl_set_intensity(NULL, CORGI_DEFAULT_INTENSITY);
+
+ printk("Corgi Backlight Driver Initialized.\n");
+ return 0;
+}
+
+static int corgibl_remove(struct device *dev)
+{
+ backlight_device_unregister(corgi_backlight_device);
+
+ corgibl_set_intensity(NULL, 0);
+
+ printk("Corgi Backlight Driver Unloaded\n");
+ return 0;
+}
+
+static struct device_driver corgibl_driver = {
+ .name = "corgi-bl",
+ .bus = &platform_bus_type,
+ .probe = corgibl_probe,
+ .remove = corgibl_remove,
+ .suspend = corgibl_suspend,
+ .resume = corgibl_resume,
+};
+
+static int __init corgibl_init(void)
+{
+ return driver_register(&corgibl_driver);
+}
+
+static void __exit corgibl_exit(void)
+{
+ driver_unregister(&corgibl_driver);
+}
+
+module_init(corgibl_init);
+module_exit(corgibl_exit);
+
+MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
+MODULE_DESCRIPTION("Corgi Backlight Driver");
+MODULE_LICENSE("GPLv2");
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