[PATCH v4/cleanup] viafb: I2C/DDC legacy & detect output device if

[PATCH v4/cleanup] viafb: I2C/DDC legacy & detect output device if

[Dzianis Kahanovich]

Adding output device detection. Including legacy I2C/DDC code, currently safe
mostly for LCD, think "unknown" device as forced CRT. Detect whole output config
if "viafb_active_dev" unset, or undetected else LCDs in other cases. Also early
viafb_crt_enable if CRT ON - to force CRT DDC detection and multi-out in
textmode as positive side-effect.

Signed-off-by: Dzianis Kahanovich <mahatma@eu.by>
---
--- a/drivers/video/via/viafbdev.c	2010-12-18 06:42:37.000000000 +0200
+++ b/drivers/video/via/viafbdev.c	2010-12-20 20:17:42.000000000 +0200
@@ -1670,6 +1670,119 @@ static int parse_mode(const char *str, u
 	return 0;
 }

+/* Add devices, detected only via i2c legacy.
+   Really there may be CRT too, but unless I got no CRT DDC - LCD only.
+   Possible CRT may be found as "unknown" to keep CRT ON.
+   Set LCD/DVI/CRT if viafb_active_dev unset. */
+static void viafb_detect_dev(struct viafb_dev *vdev)
+{
+	u8 *edid;
+	struct fb_var_screeninfo var;
+	int i, t, ndev = 0, nlcd = 0, unknown = 0;
+	struct i2c_adapter *adapter;
+	struct lvds_setting_information *inf;
+
+	/* FIXME: viaparinfo1->chip_info looks equal to viaparinfo */
+	if (viaparinfo->chip_info->tmds_chip_info.tmds_chip_name) {
+		ndev++;
+		if (!viafb_active_dev)
+			viafb_DVI_ON = STATE_ON;
+	}
+	if (viaparinfo->chip_info->lvds_chip_info.lvds_chip_name) {
+		ndev++;
+		nlcd = 1;
+		if (!viafb_active_dev)
+			viafb_LCD_ON = STATE_ON;
+	}
+	if (viaparinfo->chip_info->lvds_chip_info2.lvds_chip_name) {
+		ndev++;
+		nlcd = 2;
+		if (!viafb_active_dev)
+			viafb_LCD2_ON = STATE_ON;
+	}
+	/* enabling CRT in textmode is at least no bad */
+	if (viafb_CRT_ON) {
+		ndev++;
+		viafb_crt_enable();
+	}
+	for (i = 0; i < VIAFB_NUM_PORTS; i++) {
+		t = vdev->port_cfg[i].type;
+		/* detect only i2c ports, undetected in other places */
+		if ((viaparinfo && viaparinfo->chip_info && (
+		    (viaparinfo->chip_info->tmds_chip_info.tmds_chip_name &&
+		    viaparinfo->chip_info->tmds_chip_info.i2c_port = t) ||
+		    (viaparinfo->chip_info->lvds_chip_info.lvds_chip_name &&
+		    viaparinfo->chip_info->lvds_chip_info.i2c_port = t) ||
+		    (viaparinfo->chip_info->lvds_chip_info2.lvds_chip_name &&
+		    viaparinfo->chip_info->lvds_chip_info2.i2c_port = t)
+		    )) || (viaparinfo1 && viaparinfo1->chip_info && (
+		    (viaparinfo1->chip_info->tmds_chip_info.tmds_chip_name &&
+		    viaparinfo1->chip_info->tmds_chip_info.i2c_port = t) ||
+		    (viaparinfo1->chip_info->lvds_chip_info.lvds_chip_name &&
+		    viaparinfo1->chip_info->lvds_chip_info.i2c_port = t) ||
+		    (viaparinfo1->chip_info->lvds_chip_info2.lvds_chip_name &&
+		    viaparinfo1->chip_info->lvds_chip_info2.i2c_port = t)
+		    )) || !(adapter = viafb_find_i2c_adapter(i)) ||
+		    !(edid = fb_ddc_read(adapter)))
+			continue;
+		memset(&var, 0, sizeof(var));
+		if (fb_parse_edid(edid, &var))
+			goto free_edid;
+		printk(KERN_INFO "viafb: %48s\n", adapter->name);
+		inf = NULL;
+		if (!nlcd) {
+			fb_edid_to_monspecs(edid, &viafbinfo->monspecs);
+			if (viafbinfo->monspecs.input & FB_DISP_DDI)
+				inf = viaparinfo->lvds_setting_info;
+			else
+				unknown++;
+		} else if (nlcd > 1) {
+			printk(KERN_ERR "viafb: too many LCD\n");
+			unknown++;
+		} else if (viafb_dual_fb) {
+			fb_edid_to_monspecs(edid, &viafbinfo1->monspecs);
+			if (viafbinfo1->monspecs.input & FB_DISP_DDI)
+				inf = viaparinfo1->lvds_setting_info;
+			else
+				unknown++;
+		} else {
+			fb_edid_to_monspecs(edid, &viafbinfo->monspecs);
+			if (viafbinfo->monspecs.input & FB_DISP_DDI)
+				inf = viaparinfo->lvds_setting_info2;
+			else
+				unknown++;
+		}
+		if (inf) {
+			if (!viafb_active_dev) {
+				if (nlcd)
+					viafb_LCD2_ON = STATE_ON;
+				else
+					viafb_LCD_ON = STATE_ON;
+			}
+			nlcd++;
+			if (var.xres)
+				inf->lcd_panel_hres = var.xres;
+			if (var.yres)
+				inf->lcd_panel_vres = var.yres;
+		}
+		ndev++;
+free_edid:
+		kfree(edid);
+	}
+	if (!viafb_active_dev) {
+		/* prefer CRT OFF if other devices */
+		if (!unknown && ndev > 1) {
+			viafb_CRT_ON = STATE_OFF;
+			viafb_crt_disable();
+		}
+		viafb_DeviceStatus = viafb_primary_dev +		    viafb_CRT_ON ? CRT_Device :
+		    viafb_DVI_ON ? DVI_Device :
+		    viafb_LCD_ON ? LCD_Device : None_Device;
+		viafb_set_iga_path();
+	}
+}
+

 #ifdef CONFIG_PM
 static int viafb_suspend(void *unused)
@@ -1891,6 +2004,7 @@ int __devinit via_fb_pci_probe(struct vi

 	viafb_init_proc(viaparinfo->shared);
 	viafb_init_dac(IGA2);
+	viafb_detect_dev(vdev);

 #ifdef CONFIG_PM
 	viafb_pm_register(&viafb_fb_pm_hooks);
--