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-rw-r--r--arch/powerpc/platforms/powermac/backlight.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powermac/backlight.c b/arch/powerpc/platforms/powermac/backlight.c
new file mode 100644
index 000000000000..8be2f7d071f0
--- /dev/null
+++ b/arch/powerpc/platforms/powermac/backlight.c
@@ -0,0 +1,202 @@
+/*
+ * Miscellaneous procedures for dealing with the PowerMac hardware.
+ * Contains support for the backlight.
+ *
+ * Copyright (C) 2000 Benjamin Herrenschmidt
+ *
+ */
+
+#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 <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/nvram.h>
+#include <asm/backlight.h>
+
+#include <linux/adb.h>
+#include <linux/pmu.h>
+
+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 backlight_callback(void *);
+static DECLARE_WORK(backlight_work, backlight_callback, NULL);
+
+void register_backlight_controller(struct backlight_controller *ctrler,
+ void *data, char *type)
+{
+ struct device_node* bk_node;
+ char *prop;
+ int valid = 0;
+
+ /* There's already a matching controller, bail out */
+ if (backlighter != NULL)
+ return;
+
+ 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;
+ }
+ 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;
+ }
+
+#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;
+ }
+#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);
+}
+EXPORT_SYMBOL(register_backlight_controller);
+
+void unregister_backlight_controller(struct backlight_controller
+ *ctrler, void *data)
+{
+ /* We keep the current backlight level (for now) */
+ if (ctrler == backlighter && data == backlighter_data)
+ backlighter = NULL;
+}
+EXPORT_SYMBOL(unregister_backlight_controller);
+
+static int __set_backlight_enable(int enable)
+{
+ 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 set_backlight_enable(int enable)
+{
+ if (!backlighter)
+ return -ENODEV;
+ backlight_req_enable = enable;
+ schedule_work(&backlight_work);
+ return 0;
+}
+
+EXPORT_SYMBOL(set_backlight_enable);
+
+int get_backlight_enable(void)
+{
+ if (!backlighter)
+ return -ENODEV;
+ return backlight_enabled;
+}
+EXPORT_SYMBOL(get_backlight_enable);
+
+static int __set_backlight_level(int level)
+{
+ 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;
+}
+int set_backlight_level(int level)
+{
+ if (!backlighter)
+ return -ENODEV;
+ backlight_req_level = level;
+ schedule_work(&backlight_work);
+ return 0;
+}
+
+EXPORT_SYMBOL(set_backlight_level);
+
+int get_backlight_level(void)
+{
+ if (!backlighter)
+ return -ENODEV;
+ return backlight_level;
+}
+EXPORT_SYMBOL(get_backlight_level);
+
+static void backlight_callback(void *dummy)
+{
+ 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);
+}