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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/video/backlight/lcd.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/video/backlight/lcd.c')
-rw-r--r--drivers/video/backlight/lcd.c263
1 files changed, 263 insertions, 0 deletions
diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c
new file mode 100644
index 000000000000..470e6f0ee4dd
--- /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");