From: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
This patch adds YeeLoong Backlight Driver, which provides standard
interface for user-space applications to control the brightness of the
backlight.
Signed-off-by: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
---
.../loongson/lemote-2f/yeeloong_laptop/Kconfig | 9 ++-
.../loongson/lemote-2f/yeeloong_laptop/Makefile | 2 +
.../lemote-2f/yeeloong_laptop/ec_kb3310b.h | 1 +
.../lemote-2f/yeeloong_laptop/yl_backlight.c | 93 ++++++++++++++++++++
4 files changed, 104 insertions(+), 1 deletions(-)
create mode 100644 arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_backlight.c
diff --git a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig
index d6df9b7..02d36d8 100644
--- a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig
+++ b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig
@@ -10,6 +10,13 @@ menuconfig LEMOTE_YEELOONG2F
if LEMOTE_YEELOONG2F
-
+config YEELOONG_BACKLIGHT
+ tristate "Backlight Driver"
+ select BACKLIGHT_CLASS_DEVICE
+ default y
+ help
+ This option adds YeeLoong Backlight Driver, which provides standard
+ interface for user-space applications to control the brightness of
+ the backlight.
endif
diff --git a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile
index 90c4ce5..6c3d3dc 100644
--- a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile
+++ b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile
@@ -1,3 +1,5 @@
# YeeLoong Specific
obj-y += ec_kb3310b.o
+
+obj-$(CONFIG_YEELOONG_BACKLIGHT) += yl_backlight.o
diff --git a/arch/mips/loongson/lemote-2f/yeeloong_laptop/ec_kb3310b.h b/arch/mips/loongson/lemote-2f/yeeloong_laptop/ec_kb3310b.h
index 762d888..0e3b5ad 100644
--- a/arch/mips/loongson/lemote-2f/yeeloong_laptop/ec_kb3310b.h
+++ b/arch/mips/loongson/lemote-2f/yeeloong_laptop/ec_kb3310b.h
@@ -23,6 +23,7 @@ typedef int (*sci_handler) (int status);
extern sci_handler yeeloong_report_lid_status;
#define SCI_IRQ_NUM 0x0A
+#define MAX_BRIGHTNESS 8
/*
* The following registers are determined by the EC index configuration.
diff --git a/arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_backlight.c b/arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_backlight.c
new file mode 100644
index 0000000..481d2ca
--- /dev/null
+++ b/arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_backlight.c
@@ -0,0 +1,93 @@
+/*
+ * YeeLoong Backlight Driver
+ *
+ * Copyright (C) 2009 Lemote Inc.
+ * Author: Wu Zhangjin <wuzj@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/backlight.h>
+#include <linux/err.h>
+#include <linux/fb.h>
+
+#include <asm/bootinfo.h>
+
+#include "ec_kb3310b.h"
+
+MODULE_AUTHOR("Wu Zhangjin <wuzj@xxxxxxxxxx>");
+MODULE_DESCRIPTION("YeeLoong laptop backlight driver");
+MODULE_LICENSE("GPL");
+
+static int yeeloong_set_brightness(struct backlight_device *bd)
+{
+ unsigned int level, current_level;
+ static unsigned int old_level;
+
+ level = (bd->props.fb_blank == FB_BLANK_UNBLANK &&
+ bd->props.power == FB_BLANK_UNBLANK) ?
+ bd->props.brightness : 0;
+
+ if (level > MAX_BRIGHTNESS)
+ level = MAX_BRIGHTNESS;
+ else if (level < 0)
+ level = 0;
+
+ /* Avoid to modify the brightness when EC is tuning it */
+ current_level = ec_read(REG_DISPLAY_BRIGHTNESS);
+ if ((old_level == current_level) && (old_level != level))
+ ec_write(REG_DISPLAY_BRIGHTNESS, level);
+ old_level = level;
+
+ return 0;
+}
+
+static int yeeloong_get_brightness(struct backlight_device *bd)
+{
+ return (int)ec_read(REG_DISPLAY_BRIGHTNESS);
+}
+
+static struct backlight_ops backlight_ops = {
+ .get_brightness = yeeloong_get_brightness,
+ .update_status = yeeloong_set_brightness,
+};
+
+static struct backlight_device *yeeloong_backlight_dev;
+
+static int __init yeeloong_backlight_init(void)
+{
+ int ret;
+
+ if (mips_machtype != MACH_LEMOTE_YL2F89) {
+ pr_err("This Driver is only for YeeLoong laptop\n");
+ return -EFAULT;
+ }
+
+ yeeloong_backlight_dev = backlight_device_register("backlight0", NULL,
+ NULL, &backlight_ops);
+
+ if (IS_ERR(yeeloong_backlight_dev)) {
+ ret = PTR_ERR(yeeloong_backlight_dev);
+ yeeloong_backlight_dev = NULL;
+ return ret;
+ }
+
+ yeeloong_backlight_dev->props.max_brightness = MAX_BRIGHTNESS;
+ yeeloong_backlight_dev->props.brightness =
+ yeeloong_get_brightness(yeeloong_backlight_dev);
+ backlight_update_status(yeeloong_backlight_dev);
+
+ return 0;
+}
+
+static void __exit yeeloong_backlight_exit(void)
+{
+ if (yeeloong_backlight_dev) {
+ backlight_device_unregister(yeeloong_backlight_dev);
+ yeeloong_backlight_dev = NULL;
+ }
+}
+
+module_init(yeeloong_backlight_init);
+module_exit(yeeloong_backlight_exit);
--
1.6.2.1
