video: tegra: fb: Configure dc from fb

This patch contains following changes:
1. Modify tegra_fb_update_monspecs to select best mode to apply
   on framebuffer, in HDMI hotplug.
2. Add a console_lock to prevent corruption while fbcon running
   in multiple threads.
3. Add a tegra_dc_disable/enable in tegra_fb_set_par to reflect
   the programmed new mode applied on DC.

Bug: 1005399
Change-Id: I133b38b00f25f767afc05549550fecde8d092fb2
Signed-off-by: Shashank Sharma <shashanks@nvidia.com>
Reviewed-on: http://git-master/r/120932
(cherry picked from commit ec7552ef36c0d0979cb31db6d2d4bd54e7f1c9fb)
Reviewed-on: http://git-master/r/140031
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Matthew Pedro <mapedro@nvidia.com>
Tested-by: Matthew Pedro <mapedro@nvidia.com>
Reviewed-by: Winnie Hsu <whsu@nvidia.com>

1 files changed, 95 insertions, 5 deletions

diff --git a/drivers/video/tegra/fb.c b/drivers/video/tegra/fb.c
index 69b30884e4df..da7b9d157402 100644
--- a/drivers/video/tegra/fb.c
+++ b/drivers/video/tegra/fb.c
@@ -38,6 +38,8 @@
 #include <mach/fb.h>
 #include <linux/nvhost.h>
 #include <linux/nvmap.h>
+#include <linux/console.h>
+
 
 #include "host/dev.h"
 #include "nvmap/nvmap.h"
@@ -158,8 +160,10 @@ static int tegra_fb_set_par(struct fb_info *info)
 #else
 					FB_VMODE_STEREO_LEFT_RIGHT);
 #endif
-
 		tegra_dc_set_fb_mode(tegra_fb->win->dc, info->mode, stereo);
+		/* Reflect the mode change on dc */
+		tegra_dc_disable(tegra_fb->win->dc);
+		tegra_dc_enable(tegra_fb->win->dc);
 
 		tegra_fb->win->w.full = dfixed_const(info->mode->xres);
 		tegra_fb->win->h.full = dfixed_const(info->mode->yres);
@@ -437,13 +441,62 @@ static struct fb_ops tegra_fb_ops = {
 	.fb_ioctl = tegra_fb_ioctl,
 };
 
+const struct fb_videomode *tegra_fb_find_best_mode(
+	struct fb_var_screeninfo *var,
+	struct list_head *head)
+{
+	struct list_head *pos;
+	struct fb_modelist *modelist;
+	struct fb_videomode *mode, *best = NULL;
+	int diff = 0;
+
+	list_for_each(pos, head) {
+		int d;
+
+		modelist = list_entry(pos, struct fb_modelist, list);
+		mode = &modelist->mode;
+
+		if (mode->xres >= var->xres && mode->yres >= var->yres) {
+			d = (mode->xres - var->xres) +
+				(mode->yres - var->yres);
+			if (diff < d) {
+				diff = d;
+				best = mode;
+			} else if (diff == d && best &&
+				   mode->refresh > best->refresh)
+				best = mode;
+		}
+	}
+	return best;
+}
+
+static int tegra_fb_activate_mode(struct tegra_fb_info *fb_info,
+				struct fb_var_screeninfo *var)
+{
+	int err;
+	struct fb_info *info = fb_info->info;
+
+	console_lock();
+	info->flags |= FBINFO_MISC_USEREVENT;
+	err = fb_set_var(info, var);
+	info->flags &= ~FBINFO_MISC_USEREVENT;
+	console_unlock();
+	if (err)
+		return err;
+	return 0;
+}
+
 void tegra_fb_update_monspecs(struct tegra_fb_info *fb_info,
 			      struct fb_monspecs *specs,
 			      bool (*mode_filter)(const struct tegra_dc *dc,
 						  struct fb_videomode *mode))
 {
-	struct fb_event event;
 	int i;
+	int ret = 0;
+	struct fb_event event;
+	struct fb_info *info = fb_info->info;
+	const struct fb_videomode *best_mode = NULL;
+	struct fb_var_screeninfo var = {0,};
 
 	mutex_lock(&fb_info->info->lock);
 	fb_destroy_modedb(fb_info->info->monspecs.modedb);
@@ -470,19 +523,56 @@ void tegra_fb_update_monspecs(struct tegra_fb_info *fb_info,
 	       sizeof(fb_info->info->monspecs));
 	fb_info->info->mode = specs->modedb;
 
+	/* Prepare a mode db */
 	for (i = 0; i < specs->modedb_len; i++) {
-		if (mode_filter) {
-			if (mode_filter(fb_info->win->dc, &specs->modedb[i]))
-				fb_add_videomode(&specs->modedb[i],
+		if (info->fbops->fb_check_var) {
+			struct fb_videomode m;
+
+			/* Call mode filter to check mode */
+			fb_videomode_to_var(&var, &specs->modedb[i]);
+			if (!(info->fbops->fb_check_var(&var, info))) {
+				fb_var_to_videomode(&m, &var);
+				fb_add_videomode(&m,
 						 &fb_info->info->modelist);
+			}
 		} else {
 			fb_add_videomode(&specs->modedb[i],
 					 &fb_info->info->modelist);
 		}
 	}
 
+	/* Get the best mode from modedb and apply on fb */
+	var.xres = 0;
+	var.yres = 0;
+	best_mode = tegra_fb_find_best_mode(&var, &info->modelist);
+
+	/* Update framebuffer with best mode */
+	fb_videomode_to_var(&var, best_mode);
+
+	/* TODO: Get proper way of getting rid of a 0 bpp */
+	if (!var.bits_per_pixel)
+		var.bits_per_pixel = 32;
+
+	memcpy(&info->var, &var, sizeof(struct fb_var_screeninfo));
+
+	ret = tegra_fb_activate_mode(fb_info, &var);
+	if (ret)
+		return;
+
 	event.info = fb_info->info;
+
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE
+/* Lock the console before sending the noti. Fbconsole
+  * on HDMI might be using console
+  */
+	console_lock();
+#endif
 	fb_notifier_call_chain(FB_EVENT_NEW_MODELIST, &event);
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE
+/* Unlock the console */
+	console_unlock();
+#endif
+
 	mutex_unlock(&fb_info->info->lock);
 }