From 5474c120aafe78ca54bf272f7a01107c42da2b21 Mon Sep 17 00:00:00 2001 From: Michael Hanselmann Date: Sun, 25 Jun 2006 05:47:08 -0700 Subject: [PATCH] Rewritten backlight infrastructure for portable Apple computers This patch contains a total rewrite of the backlight infrastructure for portable Apple computers. Backward compatibility is retained. A sysfs interface allows userland to control the brightness with more steps than before. Userland is allowed to upload a brightness curve for different monitors, similar to Mac OS X. [akpm@osdl.org: add needed exports] Signed-off-by: Michael Hanselmann Acked-by: Benjamin Herrenschmidt Cc: Richard Purdie Cc: "Antonino A. Daplas" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/macintosh/via-pmu-backlight.c | 150 ++++++++++++++++++++++++++++++++++ 1 file changed, 150 insertions(+) create mode 100644 drivers/macintosh/via-pmu-backlight.c (limited to 'drivers/macintosh/via-pmu-backlight.c') diff --git a/drivers/macintosh/via-pmu-backlight.c b/drivers/macintosh/via-pmu-backlight.c new file mode 100644 index 000000000000..b42d05f2aaff --- /dev/null +++ b/drivers/macintosh/via-pmu-backlight.c @@ -0,0 +1,150 @@ +/* + * Backlight code for via-pmu + * + * Copyright (C) 1998 Paul Mackerras and Fabio Riccardi. + * Copyright (C) 2001-2002 Benjamin Herrenschmidt + * Copyright (C) 2006 Michael Hanselmann + * + */ + +#include +#include +#include +#include +#include + +#define MAX_PMU_LEVEL 0xFF + +static struct device_node *vias; +static struct backlight_properties pmu_backlight_data; + +static int pmu_backlight_get_level_brightness(struct fb_info *info, + int level) +{ + int pmulevel; + + /* Get and convert the value */ + mutex_lock(&info->bl_mutex); + pmulevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL; + mutex_unlock(&info->bl_mutex); + + 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 fb_info *info = class_get_devdata(&bd->class_dev); + struct adb_request req; + int pmulevel, level = bd->props->brightness; + + if (vias == NULL) + return -ENODEV; + + if (bd->props->power != FB_BLANK_UNBLANK || + bd->props->fb_blank != FB_BLANK_UNBLANK) + level = 0; + + pmulevel = pmu_backlight_get_level_brightness(info, 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 | (level > 0 ? PMU_POW_ON : PMU_POW_OFF)); + pmu_wait_complete(&req); + + return 0; +} + +static int pmu_backlight_get_brightness(struct backlight_device *bd) +{ + return bd->props->brightness; +} + +static struct backlight_properties pmu_backlight_data = { + .owner = THIS_MODULE, + .get_brightness = pmu_backlight_get_brightness, + .update_status = pmu_backlight_update_status, + .max_brightness = (FB_BACKLIGHT_LEVELS - 1), +}; + +void __init pmu_backlight_init(struct device_node *in_vias) +{ + struct backlight_device *bd; + struct fb_info *info; + char name[10]; + int level, autosave; + + vias = in_vias; + + /* Special case for the old PowerBook since I can't test on it */ + autosave = + machine_is_compatible("AAPL,3400/2400") || + machine_is_compatible("AAPL,3500"); + + if (!autosave && + !pmac_has_backlight_type("pmu") && + !machine_is_compatible("AAPL,PowerBook1998") && + !machine_is_compatible("PowerBook1,1")) + return; + + /* Actually, this is a hack, but I don't know of a better way + * to get the first framebuffer device. + */ + info = registered_fb[0]; + if (!info) { + printk("pmubl: No framebuffer found\n"); + goto error; + } + + snprintf(name, sizeof(name), "pmubl%d", info->node); + + bd = backlight_device_register(name, info, &pmu_backlight_data); + if (IS_ERR(bd)) { + printk("pmubl: Backlight registration failed\n"); + goto error; + } + + mutex_lock(&info->bl_mutex); + info->bl_dev = bd; + fb_bl_default_curve(info, 0x7F, 0x46, 0x0E); + mutex_unlock(&info->bl_mutex); + + level = pmu_backlight_data.max_brightness; + + if (autosave) { + /* read autosaved value if available */ + struct adb_request req; + pmu_request(&req, NULL, 2, 0xd9, 0); + pmu_wait_complete(&req); + + mutex_lock(&info->bl_mutex); + level = pmac_backlight_curve_lookup(info, + (req.reply[0] >> 4) * + pmu_backlight_data.max_brightness / 15); + mutex_unlock(&info->bl_mutex); + } + + up(&bd->sem); + bd->props->brightness = level; + bd->props->power = FB_BLANK_UNBLANK; + bd->props->update_status(bd); + down(&bd->sem); + + mutex_lock(&pmac_backlight_mutex); + if (!pmac_backlight) + pmac_backlight = bd; + mutex_unlock(&pmac_backlight_mutex); + + printk("pmubl: Backlight initialized (%s)\n", name); + + return; + +error: + return; +} -- cgit v1.2.3