summaryrefslogtreecommitdiffstats
path: root/drivers/video/backlight
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/video/backlight')
-rw-r--r--drivers/video/backlight/Kconfig52
-rw-r--r--drivers/video/backlight/Makefile5
-rw-r--r--drivers/video/backlight/backlight.c264
-rw-r--r--drivers/video/backlight/corgi_bl.c198
-rw-r--r--drivers/video/backlight/lcd.c263
5 files changed, 782 insertions, 0 deletions
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
new file mode 100644
index 0000000..996d543
--- /dev/null
+++ b/drivers/video/backlight/Kconfig
@@ -0,0 +1,52 @@
+#
+# Backlight & LCD drivers configuration
+#
+
+menuconfig BACKLIGHT_LCD_SUPPORT
+ bool "Backlight & LCD device support"
+ help
+ Enable this to be able to choose the drivers for controlling the
+ backlight and the LCD panel on some platforms, for example on PDAs.
+
+config BACKLIGHT_CLASS_DEVICE
+ tristate "Lowlevel Backlight controls"
+ depends on BACKLIGHT_LCD_SUPPORT
+ default m
+ help
+ This framework adds support for low-level control of the LCD
+ backlight. This includes support for brightness and power.
+
+ To have support for your specific LCD panel you will have to
+ select the proper drivers which depend on this option.
+
+config BACKLIGHT_DEVICE
+ bool
+ depends on BACKLIGHT_CLASS_DEVICE
+ default y
+
+config LCD_CLASS_DEVICE
+ tristate "Lowlevel LCD controls"
+ depends on BACKLIGHT_LCD_SUPPORT
+ default m
+ help
+ This framework adds support for low-level control of LCD.
+ Some framebuffer devices connect to platform-specific LCD modules
+ in order to have a platform-specific way to control the flat panel
+ (contrast and applying power to the LCD (not to the backlight!)).
+
+ To have support for your specific LCD panel you will have to
+ select the proper drivers which depend on this option.
+
+config LCD_DEVICE
+ bool
+ depends on LCD_CLASS_DEVICE
+ default y
+
+config BACKLIGHT_CORGI
+ tristate "Sharp Corgi Backlight Driver (SL-C7xx Series)"
+ depends on BACKLIGHT_DEVICE && PXA_SHARPSL
+ default y
+ help
+ If you have a Sharp Zaurus SL-C7xx, say y to enable the
+ backlight driver.
+
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
new file mode 100644
index 0000000..9aae884
--- /dev/null
+++ b/drivers/video/backlight/Makefile
@@ -0,0 +1,5 @@
+# Backlight & LCD drivers
+
+obj-$(CONFIG_LCD_CLASS_DEVICE) += lcd.o
+obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
+obj-$(CONFIG_BACKLIGHT_CORGI) += corgi_bl.o
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
new file mode 100644
index 0000000..acc81cb
--- /dev/null
+++ b/drivers/video/backlight/backlight.c
@@ -0,0 +1,264 @@
+/*
+ * Backlight Lowlevel Control Abstraction
+ *
+ * Copyright (C) 2003,2004 Hewlett-Packard Company
+ *
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/backlight.h>
+#include <linux/notifier.h>
+#include <linux/ctype.h>
+#include <linux/err.h>
+#include <linux/fb.h>
+#include <asm/bug.h>
+
+static ssize_t backlight_show_power(struct class_device *cdev, char *buf)
+{
+ int rc;
+ struct backlight_device *bd = to_backlight_device(cdev);
+
+ down(&bd->sem);
+ if (likely(bd->props && bd->props->get_power))
+ rc = sprintf(buf, "%d\n", bd->props->get_power(bd));
+ else
+ rc = -ENXIO;
+ up(&bd->sem);
+
+ return rc;
+}
+
+static ssize_t backlight_store_power(struct class_device *cdev, const char *buf, size_t count)
+{
+ int rc, power;
+ char *endp;
+ struct backlight_device *bd = to_backlight_device(cdev);
+
+ power = simple_strtoul(buf, &endp, 0);
+ if (*endp && !isspace(*endp))
+ return -EINVAL;
+
+ down(&bd->sem);
+ if (likely(bd->props && bd->props->set_power)) {
+ pr_debug("backlight: set power to %d\n", power);
+ bd->props->set_power(bd, power);
+ rc = count;
+ } else
+ rc = -ENXIO;
+ up(&bd->sem);
+
+ return rc;
+}
+
+static ssize_t backlight_show_brightness(struct class_device *cdev, char *buf)
+{
+ int rc;
+ struct backlight_device *bd = to_backlight_device(cdev);
+
+ down(&bd->sem);
+ if (likely(bd->props && bd->props->get_brightness))
+ rc = sprintf(buf, "%d\n", bd->props->get_brightness(bd));
+ else
+ rc = -ENXIO;
+ up(&bd->sem);
+
+ return rc;
+}
+
+static ssize_t backlight_store_brightness(struct class_device *cdev, const char *buf, size_t count)
+{
+ int rc, brightness;
+ char *endp;
+ struct backlight_device *bd = to_backlight_device(cdev);
+
+ brightness = simple_strtoul(buf, &endp, 0);
+ if (*endp && !isspace(*endp))
+ return -EINVAL;
+
+ down(&bd->sem);
+ if (likely(bd->props && bd->props->set_brightness)) {
+ pr_debug("backlight: set brightness to %d\n", brightness);
+ bd->props->set_brightness(bd, brightness);
+ rc = count;
+ } else
+ rc = -ENXIO;
+ up(&bd->sem);
+
+ return rc;
+}
+
+static ssize_t backlight_show_max_brightness(struct class_device *cdev, char *buf)
+{
+ int rc;
+ struct backlight_device *bd = to_backlight_device(cdev);
+
+ down(&bd->sem);
+ if (likely(bd->props))
+ rc = sprintf(buf, "%d\n", bd->props->max_brightness);
+ else
+ rc = -ENXIO;
+ up(&bd->sem);
+
+ return rc;
+}
+
+static void backlight_class_release(struct class_device *dev)
+{
+ struct backlight_device *bd = to_backlight_device(dev);
+ kfree(bd);
+}
+
+static struct class backlight_class = {
+ .name = "backlight",
+ .release = backlight_class_release,
+};
+
+#define DECLARE_ATTR(_name,_mode,_show,_store) \
+{ \
+ .attr = { .name = __stringify(_name), .mode = _mode, .owner = THIS_MODULE }, \
+ .show = _show, \
+ .store = _store, \
+}
+
+static struct class_device_attribute bl_class_device_attributes[] = {
+ DECLARE_ATTR(power, 0644, backlight_show_power, backlight_store_power),
+ DECLARE_ATTR(brightness, 0644, backlight_show_brightness, backlight_store_brightness),
+ DECLARE_ATTR(max_brightness, 0444, backlight_show_max_brightness, NULL),
+};
+
+/* This callback gets called when something important happens inside a
+ * framebuffer driver. We're looking if that important event is blanking,
+ * and if it is, we're switching backlight power as well ...
+ */
+static int fb_notifier_callback(struct notifier_block *self,
+ unsigned long event, void *data)
+{
+ struct backlight_device *bd;
+ struct fb_event *evdata =(struct fb_event *)data;
+
+ /* If we aren't interested in this event, skip it immediately ... */
+ if (event != FB_EVENT_BLANK)
+ return 0;
+
+ bd = container_of(self, struct backlight_device, fb_notif);
+ down(&bd->sem);
+ if (bd->props)
+ if (!bd->props->check_fb || bd->props->check_fb(evdata->info))
+ bd->props->set_power(bd, *(int *)evdata->data);
+ up(&bd->sem);
+ return 0;
+}
+
+/**
+ * backlight_device_register - create and register a new object of
+ * backlight_device class.
+ * @name: the name of the new object(must be the same as the name of the
+ * respective framebuffer device).
+ * @devdata: an optional pointer to be stored in the class_device. The
+ * methods may retrieve it by using class_get_devdata(&bd->class_dev).
+ * @bp: the backlight properties structure.
+ *
+ * Creates and registers new backlight class_device. Returns either an
+ * ERR_PTR() or a pointer to the newly allocated device.
+ */
+struct backlight_device *backlight_device_register(const char *name, void *devdata,
+ struct backlight_properties *bp)
+{
+ int i, rc;
+ struct backlight_device *new_bd;
+
+ pr_debug("backlight_device_alloc: name=%s\n", name);
+
+ new_bd = kmalloc(sizeof(struct backlight_device), GFP_KERNEL);
+ if (unlikely(!new_bd))
+ return ERR_PTR(ENOMEM);
+
+ init_MUTEX(&new_bd->sem);
+ new_bd->props = bp;
+ memset(&new_bd->class_dev, 0, sizeof(new_bd->class_dev));
+ new_bd->class_dev.class = &backlight_class;
+ strlcpy(new_bd->class_dev.class_id, name, KOBJ_NAME_LEN);
+ class_set_devdata(&new_bd->class_dev, devdata);
+
+ rc = class_device_register(&new_bd->class_dev);
+ if (unlikely(rc)) {
+error: kfree(new_bd);
+ return ERR_PTR(rc);
+ }
+
+ memset(&new_bd->fb_notif, 0, sizeof(new_bd->fb_notif));
+ new_bd->fb_notif.notifier_call = fb_notifier_callback;
+
+ rc = fb_register_client(&new_bd->fb_notif);
+ if (unlikely(rc))
+ goto error;
+
+ for (i = 0; i < ARRAY_SIZE(bl_class_device_attributes); i++) {
+ rc = class_device_create_file(&new_bd->class_dev,
+ &bl_class_device_attributes[i]);
+ if (unlikely(rc)) {
+ while (--i >= 0)
+ class_device_remove_file(&new_bd->class_dev,
+ &bl_class_device_attributes[i]);
+ class_device_unregister(&new_bd->class_dev);
+ /* No need to kfree(new_bd) since release() method was called */
+ return ERR_PTR(rc);
+ }
+ }
+
+ return new_bd;
+}
+EXPORT_SYMBOL(backlight_device_register);
+
+/**
+ * backlight_device_unregister - unregisters a backlight device object.
+ * @bd: the backlight device object to be unregistered and freed.
+ *
+ * Unregisters a previously registered via backlight_device_register object.
+ */
+void backlight_device_unregister(struct backlight_device *bd)
+{
+ int i;
+
+ if (!bd)
+ return;
+
+ pr_debug("backlight_device_unregister: name=%s\n", bd->class_dev.class_id);
+
+ for (i = 0; i < ARRAY_SIZE(bl_class_device_attributes); i++)
+ class_device_remove_file(&bd->class_dev,
+ &bl_class_device_attributes[i]);
+
+ down(&bd->sem);
+ bd->props = NULL;
+ up(&bd->sem);
+
+ fb_unregister_client(&bd->fb_notif);
+
+ class_device_unregister(&bd->class_dev);
+}
+EXPORT_SYMBOL(backlight_device_unregister);
+
+static void __exit backlight_class_exit(void)
+{
+ class_unregister(&backlight_class);
+}
+
+static int __init backlight_class_init(void)
+{
+ return class_register(&backlight_class);
+}
+
+/*
+ * if this is compiled into the kernel, we need to ensure that the
+ * class is registered before users of the class try to register lcd's
+ */
+postcore_initcall(backlight_class_init);
+module_exit(backlight_class_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jamey Hicks <jamey.hicks@hp.com>, Andrew Zabolotny <zap@homelink.ru>");
+MODULE_DESCRIPTION("Backlight Lowlevel Control Abstraction");
diff --git a/drivers/video/backlight/corgi_bl.c b/drivers/video/backlight/corgi_bl.c
new file mode 100644
index 0000000..3c026b0
--- /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");
diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c
new file mode 100644
index 0000000..470e6f0
--- /dev/null
+++ b/drivers/video/backlight/lcd.c
@@ -0,0 +1,263 @@
+/*
+ * LCD Lowlevel Control Abstraction
+ *
+ * Copyright (C) 2003,2004 Hewlett-Packard Company
+ *
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/lcd.h>
+#include <linux/notifier.h>
+#include <linux/ctype.h>
+#include <linux/err.h>
+#include <linux/fb.h>
+#include <asm/bug.h>
+
+static ssize_t lcd_show_power(struct class_device *cdev, char *buf)
+{
+ int rc;
+ struct lcd_device *ld = to_lcd_device(cdev);
+
+ down(&ld->sem);
+ if (likely(ld->props && ld->props->get_power))
+ rc = sprintf(buf, "%d\n", ld->props->get_power(ld));
+ else
+ rc = -ENXIO;
+ up(&ld->sem);
+
+ return rc;
+}
+
+static ssize_t lcd_store_power(struct class_device *cdev, const char *buf, size_t count)
+{
+ int rc, power;
+ char *endp;
+ struct lcd_device *ld = to_lcd_device(cdev);
+
+ power = simple_strtoul(buf, &endp, 0);
+ if (*endp && !isspace(*endp))
+ return -EINVAL;
+
+ down(&ld->sem);
+ if (likely(ld->props && ld->props->set_power)) {
+ pr_debug("lcd: set power to %d\n", power);
+ ld->props->set_power(ld, power);
+ rc = count;
+ } else
+ rc = -ENXIO;
+ up(&ld->sem);
+
+ return rc;
+}
+
+static ssize_t lcd_show_contrast(struct class_device *cdev, char *buf)
+{
+ int rc;
+ struct lcd_device *ld = to_lcd_device(cdev);
+
+ down(&ld->sem);
+ if (likely(ld->props && ld->props->get_contrast))
+ rc = sprintf(buf, "%d\n", ld->props->get_contrast(ld));
+ else
+ rc = -ENXIO;
+ up(&ld->sem);
+
+ return rc;
+}
+
+static ssize_t lcd_store_contrast(struct class_device *cdev, const char *buf, size_t count)
+{
+ int rc, contrast;
+ char *endp;
+ struct lcd_device *ld = to_lcd_device(cdev);
+
+ contrast = simple_strtoul(buf, &endp, 0);
+ if (*endp && !isspace(*endp))
+ return -EINVAL;
+
+ down(&ld->sem);
+ if (likely(ld->props && ld->props->set_contrast)) {
+ pr_debug("lcd: set contrast to %d\n", contrast);
+ ld->props->set_contrast(ld, contrast);
+ rc = count;
+ } else
+ rc = -ENXIO;
+ up(&ld->sem);
+
+ return rc;
+}
+
+static ssize_t lcd_show_max_contrast(struct class_device *cdev, char *buf)
+{
+ int rc;
+ struct lcd_device *ld = to_lcd_device(cdev);
+
+ down(&ld->sem);
+ if (likely(ld->props))
+ rc = sprintf(buf, "%d\n", ld->props->max_contrast);
+ else
+ rc = -ENXIO;
+ up(&ld->sem);
+
+ return rc;
+}
+
+static void lcd_class_release(struct class_device *dev)
+{
+ struct lcd_device *ld = to_lcd_device(dev);
+ kfree(ld);
+}
+
+static struct class lcd_class = {
+ .name = "lcd",
+ .release = lcd_class_release,
+};
+
+#define DECLARE_ATTR(_name,_mode,_show,_store) \
+{ \
+ .attr = { .name = __stringify(_name), .mode = _mode, .owner = THIS_MODULE }, \
+ .show = _show, \
+ .store = _store, \
+}
+
+static struct class_device_attribute lcd_class_device_attributes[] = {
+ DECLARE_ATTR(power, 0644, lcd_show_power, lcd_store_power),
+ DECLARE_ATTR(contrast, 0644, lcd_show_contrast, lcd_store_contrast),
+ DECLARE_ATTR(max_contrast, 0444, lcd_show_max_contrast, NULL),
+};
+
+/* This callback gets called when something important happens inside a
+ * framebuffer driver. We're looking if that important event is blanking,
+ * and if it is, we're switching lcd power as well ...
+ */
+static int fb_notifier_callback(struct notifier_block *self,
+ unsigned long event, void *data)
+{
+ struct lcd_device *ld;
+ struct fb_event *evdata =(struct fb_event *)data;
+
+ /* If we aren't interested in this event, skip it immediately ... */
+ if (event != FB_EVENT_BLANK)
+ return 0;
+
+ ld = container_of(self, struct lcd_device, fb_notif);
+ down(&ld->sem);
+ if (ld->props)
+ if (!ld->props->check_fb || ld->props->check_fb(evdata->info))
+ ld->props->set_power(ld, *(int *)evdata->data);
+ up(&ld->sem);
+ return 0;
+}
+
+/**
+ * lcd_device_register - register a new object of lcd_device class.
+ * @name: the name of the new object(must be the same as the name of the
+ * respective framebuffer device).
+ * @devdata: an optional pointer to be stored in the class_device. The
+ * methods may retrieve it by using class_get_devdata(ld->class_dev).
+ * @lp: the lcd properties structure.
+ *
+ * Creates and registers a new lcd class_device. Returns either an ERR_PTR()
+ * or a pointer to the newly allocated device.
+ */
+struct lcd_device *lcd_device_register(const char *name, void *devdata,
+ struct lcd_properties *lp)
+{
+ int i, rc;
+ struct lcd_device *new_ld;
+
+ pr_debug("lcd_device_register: name=%s\n", name);
+
+ new_ld = kmalloc(sizeof(struct lcd_device), GFP_KERNEL);
+ if (unlikely(!new_ld))
+ return ERR_PTR(ENOMEM);
+
+ init_MUTEX(&new_ld->sem);
+ new_ld->props = lp;
+ memset(&new_ld->class_dev, 0, sizeof(new_ld->class_dev));
+ new_ld->class_dev.class = &lcd_class;
+ strlcpy(new_ld->class_dev.class_id, name, KOBJ_NAME_LEN);
+ class_set_devdata(&new_ld->class_dev, devdata);
+
+ rc = class_device_register(&new_ld->class_dev);
+ if (unlikely(rc)) {
+error: kfree(new_ld);
+ return ERR_PTR(rc);
+ }
+
+ memset(&new_ld->fb_notif, 0, sizeof(new_ld->fb_notif));
+ new_ld->fb_notif.notifier_call = fb_notifier_callback;
+
+ rc = fb_register_client(&new_ld->fb_notif);
+ if (unlikely(rc))
+ goto error;
+
+ for (i = 0; i < ARRAY_SIZE(lcd_class_device_attributes); i++) {
+ rc = class_device_create_file(&new_ld->class_dev,
+ &lcd_class_device_attributes[i]);
+ if (unlikely(rc)) {
+ while (--i >= 0)
+ class_device_remove_file(&new_ld->class_dev,
+ &lcd_class_device_attributes[i]);
+ class_device_unregister(&new_ld->class_dev);
+ /* No need to kfree(new_ld) since release() method was called */
+ return ERR_PTR(rc);
+ }
+ }
+
+ return new_ld;
+}
+EXPORT_SYMBOL(lcd_device_register);
+
+/**
+ * lcd_device_unregister - unregisters a object of lcd_device class.
+ * @ld: the lcd device object to be unregistered and freed.
+ *
+ * Unregisters a previously registered via lcd_device_register object.
+ */
+void lcd_device_unregister(struct lcd_device *ld)
+{
+ int i;
+
+ if (!ld)
+ return;
+
+ pr_debug("lcd_device_unregister: name=%s\n", ld->class_dev.class_id);
+
+ for (i = 0; i < ARRAY_SIZE(lcd_class_device_attributes); i++)
+ class_device_remove_file(&ld->class_dev,
+ &lcd_class_device_attributes[i]);
+
+ down(&ld->sem);
+ ld->props = NULL;
+ up(&ld->sem);
+
+ fb_unregister_client(&ld->fb_notif);
+
+ class_device_unregister(&ld->class_dev);
+}
+EXPORT_SYMBOL(lcd_device_unregister);
+
+static void __exit lcd_class_exit(void)
+{
+ class_unregister(&lcd_class);
+}
+
+static int __init lcd_class_init(void)
+{
+ return class_register(&lcd_class);
+}
+
+/*
+ * if this is compiled into the kernel, we need to ensure that the
+ * class is registered before users of the class try to register lcd's
+ */
+postcore_initcall(lcd_class_init);
+module_exit(lcd_class_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jamey Hicks <jamey.hicks@hp.com>, Andrew Zabolotny <zap@homelink.ru>");
+MODULE_DESCRIPTION("LCD Lowlevel Control Abstraction");
OpenPOWER on IntegriCloud