[PATCH 5/9] Loongson: YeeLoong: add video output driver

[Wu Zhangjin <wuzhangjin@gmail.com>]

This patch adds Video Output Driver, it provides standard
interface(/sys/class/video_output) to turn on/off the video output of
LCD, CRT.

Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
---
 drivers/platform/mips/Kconfig           |    1 +
 drivers/platform/mips/yeeloong_laptop.c |  139 +++++++++++++++++++++++++++++++
 2 files changed, 140 insertions(+), 0 deletions(-)

diff --git a/drivers/platform/mips/Kconfig b/drivers/platform/mips/Kconfig
index d4ce744..e1285f7 100644
--- a/drivers/platform/mips/Kconfig
+++ b/drivers/platform/mips/Kconfig
@@ -19,6 +19,7 @@ config LEMOTE_YEELOONG2F
 	depends on LEMOTE_MACH2F
 	select BACKLIGHT_CLASS_DEVICE
 	select HWMON
+	select VIDEO_OUTPUT_CONTROL
 	help
 	  YeeLoong netbook is a mini laptop made by Lemote, which is basically
 	  compatible to FuLoong2F mini PC, but it has an extra Embedded
diff --git a/drivers/platform/mips/yeeloong_laptop.c b/drivers/platform/mips/yeeloong_laptop.c
index a422acb..9fd70ae 100644
--- a/drivers/platform/mips/yeeloong_laptop.c
+++ b/drivers/platform/mips/yeeloong_laptop.c
@@ -14,6 +14,7 @@
 #include <linux/fb.h>
 #include <linux/hwmon.h>	/* for hwmon subdriver */
 #include <linux/hwmon-sysfs.h>
+#include <linux/video_output.h>	/* for video output subdriver */
 
 #include <ec_kb3310b.h>
 
@@ -323,6 +324,136 @@ static void yeeloong_hwmon_exit(void)
 	}
 }
 
+/* video output subdriver */
+
+static int lcd_video_output_get(struct output_device *od)
+{
+	return ec_read(REG_DISPLAY_LCD);
+}
+
+#define LCD	0
+#define CRT	1
+
+static void display_vo_set(int display, int on)
+{
+	int addr;
+	unsigned long value;
+
+	addr = (display == LCD) ? 0x31 : 0x21;
+
+	outb(addr, 0x3c4);
+	value = inb(0x3c5);
+
+	if (display == LCD)
+		value |= (on ? 0x03 : 0x02);
+	else {
+		if (on)
+			clear_bit(7, &value);
+		else
+			set_bit(7, &value);
+	}
+
+	outb(addr, 0x3c4);
+	outb(value, 0x3c5);
+}
+
+static int lcd_video_output_set(struct output_device *od)
+{
+	unsigned long status;
+
+	status = !!od->request_state;
+
+	display_vo_set(LCD, status);
+	ec_write(REG_BACKLIGHT_CTRL, status);
+
+	return 0;
+}
+
+static struct output_properties lcd_output_properties = {
+	.set_state = lcd_video_output_set,
+	.get_status = lcd_video_output_get,
+};
+
+static int crt_video_output_get(struct output_device *od)
+{
+	return ec_read(REG_CRT_DETECT);
+}
+
+static int crt_video_output_set(struct output_device *od)
+{
+	unsigned long status;
+
+	status = !!od->request_state;
+
+	if (ec_read(REG_CRT_DETECT) == BIT_CRT_DETECT_PLUG)
+		display_vo_set(CRT, status);
+
+	return 0;
+}
+
+static struct output_properties crt_output_properties = {
+	.set_state = crt_video_output_set,
+	.get_status = crt_video_output_get,
+};
+
+static struct output_device *lcd_output_dev, *crt_output_dev;
+
+static void yeeloong_lcd_vo_set(int status)
+{
+	lcd_output_dev->request_state = status;
+	lcd_video_output_set(lcd_output_dev);
+}
+
+static void yeeloong_crt_vo_set(int status)
+{
+	crt_output_dev->request_state = status;
+	crt_video_output_set(crt_output_dev);
+}
+
+static int yeeloong_vo_init(void)
+{
+	int ret;
+
+	/* Register video output device: lcd, crt */
+	lcd_output_dev = video_output_register("LCD", NULL, NULL,
+			&lcd_output_properties);
+
+	if (IS_ERR(lcd_output_dev)) {
+		ret = PTR_ERR(lcd_output_dev);
+		lcd_output_dev = NULL;
+		return ret;
+	}
+	/* Ensure LCD is on by default */
+	yeeloong_lcd_vo_set(BIT_DISPLAY_LCD_ON);
+
+	crt_output_dev = video_output_register("CRT", NULL, NULL,
+			&crt_output_properties);
+
+	if (IS_ERR(crt_output_dev)) {
+		ret = PTR_ERR(crt_output_dev);
+		crt_output_dev = NULL;
+		return ret;
+	}
+
+	/* Turn off CRT by default, and will be enabled when the CRT
+	 * connectting event reported by SCI */
+	yeeloong_crt_vo_set(BIT_CRT_DETECT_UNPLUG);
+
+	return 0;
+}
+
+static void yeeloong_vo_exit(void)
+{
+	if (lcd_output_dev) {
+		video_output_unregister(lcd_output_dev);
+		lcd_output_dev = NULL;
+	}
+	if (crt_output_dev) {
+		video_output_unregister(crt_output_dev);
+		crt_output_dev = NULL;
+	}
+}
+
 static struct platform_device_id platform_device_ids[] = {
 	{
 		.name = "yeeloong_laptop",
@@ -367,11 +498,19 @@ static int __init yeeloong_init(void)
 		return ret;
 	}
 
+	ret = yeeloong_vo_init();
+	if (ret) {
+		pr_err("Fail to register yeeloong video output driver.\n");
+		yeeloong_vo_exit();
+		return ret;
+	}
+
 	return 0;
 }
 
 static void __exit yeeloong_exit(void)
 {
+	yeeloong_vo_exit();
 	yeeloong_hwmon_exit();
 	yeeloong_backlight_exit();
 	platform_driver_unregister(&platform_driver);
-- 
1.7.0.4