* Contains support for the backlight.
*
* Copyright (C) 2000 Benjamin Herrenschmidt
+ * Copyright (C) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
*
*/
-#include <linux/config.h>
#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/stddef.h>
-#include <linux/reboot.h>
-#include <linux/nvram.h>
-#include <linux/console.h>
-#include <asm/sections.h>
-#include <asm/ptrace.h>
-#include <asm/io.h>
-#include <asm/pgtable.h>
-#include <asm/system.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+#include <linux/adb.h>
+#include <linux/pmu.h>
+#include <asm/atomic.h>
#include <asm/prom.h>
-#include <asm/machdep.h>
-#include <asm/nvram.h>
#include <asm/backlight.h>
-#include <linux/adb.h>
-#include <linux/pmu.h>
+#define OLD_BACKLIGHT_MAX 15
-static struct backlight_controller *backlighter;
-static void* backlighter_data;
-static int backlight_autosave;
-static int backlight_level = BACKLIGHT_MAX;
-static int backlight_enabled = 1;
-static int backlight_req_level = -1;
-static int backlight_req_enable = -1;
+static void pmac_backlight_key_worker(void *data);
+static void pmac_backlight_set_legacy_worker(void *data);
-static void backlight_callback(void *);
-static DECLARE_WORK(backlight_work, backlight_callback, NULL);
+static DECLARE_WORK(pmac_backlight_key_work, pmac_backlight_key_worker, NULL);
+static DECLARE_WORK(pmac_backlight_set_legacy_work, pmac_backlight_set_legacy_worker, NULL);
-void register_backlight_controller(struct backlight_controller *ctrler,
- void *data, char *type)
-{
- struct device_node* bk_node;
- char *prop;
- int valid = 0;
+/* Although these variables are used in interrupt context, it makes no sense to
+ * protect them. No user is able to produce enough key events per second and
+ * notice the errors that might happen.
+ */
+static int pmac_backlight_key_queued;
+static int pmac_backlight_set_legacy_queued;
- /* There's already a matching controller, bail out */
- if (backlighter != NULL)
- return;
+/* The via-pmu code allows the backlight to be grabbed, in which case the
+ * in-kernel control of the brightness needs to be disabled. This should
+ * only be used by really old PowerBooks.
+ */
+static atomic_t kernel_backlight_disabled = ATOMIC_INIT(0);
+
+/* Protect the pmac_backlight variable */
+DEFINE_MUTEX(pmac_backlight_mutex);
+
+/* Main backlight storage
+ *
+ * Backlight drivers in this variable are required to have the "props"
+ * attribute set and to have an update_status function.
+ *
+ * We can only store one backlight here, but since Apple laptops have only one
+ * internal display, it doesn't matter. Other backlight drivers can be used
+ * independently.
+ *
+ * Lock ordering:
+ * pmac_backlight_mutex (global, main backlight)
+ * pmac_backlight->sem (backlight class)
+ */
+struct backlight_device *pmac_backlight;
+
+int pmac_has_backlight_type(const char *type)
+{
+ struct device_node* bk_node = find_devices("backlight");
- bk_node = find_devices("backlight");
-
-#ifdef CONFIG_ADB_PMU
- /* Special case for the old PowerBook since I can't test on it */
- backlight_autosave = machine_is_compatible("AAPL,3400/2400")
- || machine_is_compatible("AAPL,3500");
- if ((backlight_autosave
- || machine_is_compatible("AAPL,PowerBook1998")
- || machine_is_compatible("PowerBook1,1"))
- && !strcmp(type, "pmu"))
- valid = 1;
-#endif
if (bk_node) {
- prop = get_property(bk_node, "backlight-control", NULL);
- if (prop && !strncmp(prop, type, strlen(type)))
- valid = 1;
+ char *prop = get_property(bk_node, "backlight-control", NULL);
+ if (prop && strncmp(prop, type, strlen(type)) == 0)
+ return 1;
}
- if (!valid)
- return;
- backlighter = ctrler;
- backlighter_data = data;
-
- if (bk_node && !backlight_autosave)
- prop = get_property(bk_node, "bklt", NULL);
- else
- prop = NULL;
- if (prop) {
- backlight_level = ((*prop)+1) >> 1;
- if (backlight_level > BACKLIGHT_MAX)
- backlight_level = BACKLIGHT_MAX;
+
+ return 0;
+}
+
+int pmac_backlight_curve_lookup(struct fb_info *info, int value)
+{
+ int level = (FB_BACKLIGHT_LEVELS - 1);
+
+ if (info && info->bl_dev) {
+ int i, max = 0;
+
+ /* Look for biggest value */
+ for (i = 0; i < FB_BACKLIGHT_LEVELS; i++)
+ max = max((int)info->bl_curve[i], max);
+
+ /* Look for nearest value */
+ for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) {
+ int diff = abs(info->bl_curve[i] - value);
+ if (diff < max) {
+ max = diff;
+ level = i;
+ }
+ }
+
}
-#ifdef CONFIG_ADB_PMU
- if (backlight_autosave) {
- struct adb_request req;
- pmu_request(&req, NULL, 2, 0xd9, 0);
- while (!req.complete)
- pmu_poll();
- backlight_level = req.reply[0] >> 4;
+ return level;
+}
+
+static void pmac_backlight_key_worker(void *data)
+{
+ if (atomic_read(&kernel_backlight_disabled))
+ return;
+
+ mutex_lock(&pmac_backlight_mutex);
+ if (pmac_backlight) {
+ struct backlight_properties *props;
+ int brightness;
+
+ down(&pmac_backlight->sem);
+ props = pmac_backlight->props;
+
+ brightness = props->brightness +
+ ((pmac_backlight_key_queued?-1:1) *
+ (props->max_brightness / 15));
+
+ if (brightness < 0)
+ brightness = 0;
+ else if (brightness > props->max_brightness)
+ brightness = props->max_brightness;
+
+ props->brightness = brightness;
+ props->update_status(pmac_backlight);
+
+ up(&pmac_backlight->sem);
}
-#endif
- acquire_console_sem();
- if (!backlighter->set_enable(1, backlight_level, data))
- backlight_enabled = 1;
- release_console_sem();
-
- printk(KERN_INFO "Registered \"%s\" backlight controller,"
- "level: %d/15\n", type, backlight_level);
+ mutex_unlock(&pmac_backlight_mutex);
}
-EXPORT_SYMBOL(register_backlight_controller);
-void unregister_backlight_controller(struct backlight_controller
- *ctrler, void *data)
+/* This function is called in interrupt context */
+void pmac_backlight_key(int direction)
{
- /* We keep the current backlight level (for now) */
- if (ctrler == backlighter && data == backlighter_data)
- backlighter = NULL;
+ if (atomic_read(&kernel_backlight_disabled))
+ return;
+
+ /* we can receive multiple interrupts here, but the scheduled work
+ * will run only once, with the last value
+ */
+ pmac_backlight_key_queued = direction;
+ schedule_work(&pmac_backlight_key_work);
}
-EXPORT_SYMBOL(unregister_backlight_controller);
-static int __set_backlight_enable(int enable)
+static int __pmac_backlight_set_legacy_brightness(int brightness)
{
- int rc;
-
- if (!backlighter)
- return -ENODEV;
- acquire_console_sem();
- rc = backlighter->set_enable(enable, backlight_level,
- backlighter_data);
- if (!rc)
- backlight_enabled = enable;
- release_console_sem();
- return rc;
+ int error = -ENXIO;
+
+ mutex_lock(&pmac_backlight_mutex);
+ if (pmac_backlight) {
+ struct backlight_properties *props;
+
+ down(&pmac_backlight->sem);
+ props = pmac_backlight->props;
+ props->brightness = brightness *
+ (props->max_brightness + 1) /
+ (OLD_BACKLIGHT_MAX + 1);
+
+ if (props->brightness > props->max_brightness)
+ props->brightness = props->max_brightness;
+ else if (props->brightness < 0)
+ props->brightness = 0;
+
+ props->update_status(pmac_backlight);
+ up(&pmac_backlight->sem);
+
+ error = 0;
+ }
+ mutex_unlock(&pmac_backlight_mutex);
+
+ return error;
}
-int set_backlight_enable(int enable)
+
+static void pmac_backlight_set_legacy_worker(void *data)
{
- if (!backlighter)
- return -ENODEV;
- backlight_req_enable = enable;
- schedule_work(&backlight_work);
- return 0;
+ if (atomic_read(&kernel_backlight_disabled))
+ return;
+
+ __pmac_backlight_set_legacy_brightness(pmac_backlight_set_legacy_queued);
}
-EXPORT_SYMBOL(set_backlight_enable);
+/* This function is called in interrupt context */
+void pmac_backlight_set_legacy_brightness_pmu(int brightness) {
+ if (atomic_read(&kernel_backlight_disabled))
+ return;
-int get_backlight_enable(void)
-{
- if (!backlighter)
- return -ENODEV;
- return backlight_enabled;
+ pmac_backlight_set_legacy_queued = brightness;
+ schedule_work(&pmac_backlight_set_legacy_work);
}
-EXPORT_SYMBOL(get_backlight_enable);
-static int __set_backlight_level(int level)
+int pmac_backlight_set_legacy_brightness(int brightness)
{
- int rc = 0;
-
- if (!backlighter)
- return -ENODEV;
- if (level < BACKLIGHT_MIN)
- level = BACKLIGHT_OFF;
- if (level > BACKLIGHT_MAX)
- level = BACKLIGHT_MAX;
- acquire_console_sem();
- if (backlight_enabled)
- rc = backlighter->set_level(level, backlighter_data);
- if (!rc)
- backlight_level = level;
- release_console_sem();
- if (!rc && !backlight_autosave) {
- level <<=1;
- if (level & 0x10)
- level |= 0x01;
- // -- todo: save to property "bklt"
- }
- return rc;
+ return __pmac_backlight_set_legacy_brightness(brightness);
}
-int set_backlight_level(int level)
+
+int pmac_backlight_get_legacy_brightness()
{
- if (!backlighter)
- return -ENODEV;
- backlight_req_level = level;
- schedule_work(&backlight_work);
- return 0;
-}
+ int result = -ENXIO;
-EXPORT_SYMBOL(set_backlight_level);
+ mutex_lock(&pmac_backlight_mutex);
+ if (pmac_backlight) {
+ struct backlight_properties *props;
-int get_backlight_level(void)
+ down(&pmac_backlight->sem);
+ props = pmac_backlight->props;
+
+ result = props->brightness *
+ (OLD_BACKLIGHT_MAX + 1) /
+ (props->max_brightness + 1);
+
+ up(&pmac_backlight->sem);
+ }
+ mutex_unlock(&pmac_backlight_mutex);
+
+ return result;
+}
+
+void pmac_backlight_disable()
{
- if (!backlighter)
- return -ENODEV;
- return backlight_level;
+ atomic_inc(&kernel_backlight_disabled);
}
-EXPORT_SYMBOL(get_backlight_level);
-static void backlight_callback(void *dummy)
+void pmac_backlight_enable()
{
- int level, enable;
-
- do {
- level = backlight_req_level;
- enable = backlight_req_enable;
- mb();
-
- if (level >= 0)
- __set_backlight_level(level);
- if (enable >= 0)
- __set_backlight_enable(enable);
- } while(cmpxchg(&backlight_req_level, level, -1) != level ||
- cmpxchg(&backlight_req_enable, enable, -1) != enable);
+ atomic_dec(&kernel_backlight_disabled);
}
+
+EXPORT_SYMBOL_GPL(pmac_backlight);
+EXPORT_SYMBOL_GPL(pmac_backlight_mutex);
+EXPORT_SYMBOL_GPL(pmac_has_backlight_type);
git.openpandora.org / pandora-kernel.git / blobdiff