Initial import

1 files changed, 189 insertions, 0 deletions

diff --git a/drivers/macintosh/via-pmu-backlight.c b/drivers/macintosh/via-pmu-backlight.c
new file mode 100644
index 000000000..6f68537c9
--- /dev/null
+++ b/drivers/macintosh/via-pmu-backlight.c
@@ -0,0 +1,189 @@
+/*
+ * Backlight code for via-pmu
+ *
+ * Copyright (C) 1998 Paul Mackerras and Fabio Riccardi.
+ * Copyright (C) 2001-2002 Benjamin Herrenschmidt
+ * Copyright (C) 2006      Michael Hanselmann <linux-kernel@hansmi.ch>
+ *
+ */
+
+#include <asm/ptrace.h>
+#include <linux/adb.h>
+#include <linux/pmu.h>
+#include <asm/backlight.h>
+#include <asm/prom.h>
+
+#define MAX_PMU_LEVEL 0xFF
+
+static const struct backlight_ops pmu_backlight_data;
+static DEFINE_SPINLOCK(pmu_backlight_lock);
+static int sleeping, uses_pmu_bl;
+static u8 bl_curve[FB_BACKLIGHT_LEVELS];
+
+static void pmu_backlight_init_curve(u8 off, u8 min, u8 max)
+{
+	int i, flat, count, range = (max - min);
+
+	bl_curve[0] = off;
+
+	for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
+		bl_curve[flat] = min;
+
+	count = FB_BACKLIGHT_LEVELS * 15 / 16;
+	for (i = 0; i < count; ++i)
+		bl_curve[flat + i] = min + (range * (i + 1) / count);
+}
+
+static int pmu_backlight_curve_lookup(int value)
+{
+	int level = (FB_BACKLIGHT_LEVELS - 1);
+	int i, max = 0;
+
+	/* Look for biggest value */
+	for (i = 0; i < FB_BACKLIGHT_LEVELS; i++)
+		max = max((int)bl_curve[i], max);
+
+	/* Look for nearest value */
+	for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) {
+		int diff = abs(bl_curve[i] - value);
+		if (diff < max) {
+			max = diff;
+			level = i;
+		}
+	}
+	return level;
+}
+
+static int pmu_backlight_get_level_brightness(int level)
+{
+	int pmulevel;
+
+	/* Get and convert the value */
+	pmulevel = bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL;
+	if (pmulevel < 0)
+		pmulevel = 0;
+	else if (pmulevel > MAX_PMU_LEVEL)
+		pmulevel = MAX_PMU_LEVEL;
+
+	return pmulevel;
+}
+
+static int __pmu_backlight_update_status(struct backlight_device *bd)
+{
+	struct adb_request req;
+	int level = bd->props.brightness;
+
+
+	if (bd->props.power != FB_BLANK_UNBLANK ||
+	    bd->props.fb_blank != FB_BLANK_UNBLANK)
+		level = 0;
+
+	if (level > 0) {
+		int pmulevel = pmu_backlight_get_level_brightness(level);
+
+		pmu_request(&req, NULL, 2, PMU_BACKLIGHT_BRIGHT, pmulevel);
+		pmu_wait_complete(&req);
+
+		pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
+			PMU_POW_BACKLIGHT | PMU_POW_ON);
+		pmu_wait_complete(&req);
+	} else {
+		pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
+			PMU_POW_BACKLIGHT | PMU_POW_OFF);
+		pmu_wait_complete(&req);
+	}
+
+	return 0;
+}
+
+static int pmu_backlight_update_status(struct backlight_device *bd)
+{
+	unsigned long flags;
+	int rc = 0;
+
+	spin_lock_irqsave(&pmu_backlight_lock, flags);
+	/* Don't update brightness when sleeping */
+	if (!sleeping)
+		rc = __pmu_backlight_update_status(bd);
+	spin_unlock_irqrestore(&pmu_backlight_lock, flags);
+	return rc;
+}
+
+
+static const struct backlight_ops pmu_backlight_data = {
+	.update_status	= pmu_backlight_update_status,
+
+};
+
+#ifdef CONFIG_PM
+void pmu_backlight_set_sleep(int sleep)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&pmu_backlight_lock, flags);
+	sleeping = sleep;
+	if (pmac_backlight && uses_pmu_bl) {
+		if (sleep) {
+			struct adb_request req;
+
+			pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
+				    PMU_POW_BACKLIGHT | PMU_POW_OFF);
+			pmu_wait_complete(&req);
+		} else
+			__pmu_backlight_update_status(pmac_backlight);
+	}
+	spin_unlock_irqrestore(&pmu_backlight_lock, flags);
+}
+#endif /* CONFIG_PM */
+
+void __init pmu_backlight_init()
+{
+	struct backlight_properties props;
+	struct backlight_device *bd;
+	char name[10];
+	int level, autosave;
+
+	/* Special case for the old PowerBook since I can't test on it */
+	autosave =
+		of_machine_is_compatible("AAPL,3400/2400") ||
+		of_machine_is_compatible("AAPL,3500");
+
+	if (!autosave &&
+	    !pmac_has_backlight_type("pmu") &&
+	    !of_machine_is_compatible("AAPL,PowerBook1998") &&
+	    !of_machine_is_compatible("PowerBook1,1"))
+		return;
+
+	snprintf(name, sizeof(name), "pmubl");
+
+	memset(&props, 0, sizeof(struct backlight_properties));
+	props.type = BACKLIGHT_PLATFORM;
+	props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
+	bd = backlight_device_register(name, NULL, NULL, &pmu_backlight_data,
+				       &props);
+	if (IS_ERR(bd)) {
+		printk(KERN_ERR "PMU Backlight registration failed\n");
+		return;
+	}
+	uses_pmu_bl = 1;
+	pmu_backlight_init_curve(0x7F, 0x46, 0x0E);
+
+	level = bd->props.max_brightness;
+
+	if (autosave) {
+		/* read autosaved value if available */
+		struct adb_request req;
+		pmu_request(&req, NULL, 2, 0xd9, 0);
+		pmu_wait_complete(&req);
+
+		level = pmu_backlight_curve_lookup(
+				(req.reply[0] >> 4) *
+				bd->props.max_brightness / 15);
+	}
+
+	bd->props.brightness = level;
+	bd->props.power = FB_BLANK_UNBLANK;
+	backlight_update_status(bd);
+
+	printk(KERN_INFO "PMU Backlight initialized (%s)\n", name);
+}