1 files changed, 380 insertions, 0 deletions

diff --git a/drivers/video/fbcvt.c b/drivers/video/fbcvt.c
new file mode 100644
index 0000000..cfa61b5
--- /dev/null
+++ b/drivers/video/fbcvt.c
@@ -0,0 +1,380 @@
+/*
+ * linux/drivers/video/fbcvt.c - VESA(TM) Coordinated Video Timings
+ *
+ * Copyright (C) 2005 Antonino Daplas <adaplas@pol.net>
+ *
+ *      Based from the VESA(TM) Coordinated Video Timing Generator by
+ *      Graham Loveridge April 9, 2003 available at
+ *      http://www.vesa.org/public/CVT/CVTd6r1.xls
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ *
+ */
+#include <linux/fb.h>
+
+#define FB_CVT_CELLSIZE               8
+#define FB_CVT_GTF_C                 40
+#define FB_CVT_GTF_J                 20
+#define FB_CVT_GTF_K                128
+#define FB_CVT_GTF_M                600
+#define FB_CVT_MIN_VSYNC_BP         550
+#define FB_CVT_MIN_VPORCH             3
+#define FB_CVT_MIN_BPORCH             6
+
+#define FB_CVT_RB_MIN_VBLANK        460
+#define FB_CVT_RB_HBLANK            160
+#define FB_CVT_RB_V_FPORCH            3
+
+#define FB_CVT_FLAG_REDUCED_BLANK 1
+#define FB_CVT_FLAG_MARGINS       2
+#define FB_CVT_FLAG_INTERLACED    4
+
+struct fb_cvt_data {
+	u32 xres;
+	u32 yres;
+	u32 refresh;
+	u32 f_refresh;
+	u32 pixclock;
+	u32 hperiod;
+	u32 hblank;
+	u32 hfreq;
+	u32 htotal;
+	u32 vtotal;
+	u32 vsync;
+	u32 hsync;
+	u32 h_front_porch;
+	u32 h_back_porch;
+	u32 v_front_porch;
+	u32 v_back_porch;
+	u32 h_margin;
+	u32 v_margin;
+	u32 interlace;
+	u32 aspect_ratio;
+	u32 active_pixels;
+	u32 flags;
+	u32 status;
+};
+
+static int fb_cvt_vbi_tab[] = {
+	4,        /* 4:3      */
+	5,        /* 16:9     */
+	6,        /* 16:10    */
+	7,        /* 5:4      */
+	7,        /* 15:9     */
+	8,        /* reserved */
+	9,        /* reserved */
+	10        /* custom   */
+};
+
+/* returns hperiod * 1000 */
+static u32 fb_cvt_hperiod(struct fb_cvt_data *cvt)
+{
+	u32 num = 1000000000/cvt->f_refresh;
+	u32 den;
+
+	if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) {
+		num -= FB_CVT_RB_MIN_VBLANK * 1000;
+		den = 2 * (cvt->yres/cvt->interlace + 2 * cvt->v_margin);
+	} else {
+		num -= FB_CVT_MIN_VSYNC_BP * 1000;
+		den = 2 * (cvt->yres/cvt->interlace + cvt->v_margin * 2
+			   + FB_CVT_MIN_VPORCH + cvt->interlace/2);
+	}
+
+	return 2 * (num/den);
+}
+
+/* returns ideal duty cycle * 1000 */
+static u32 fb_cvt_ideal_duty_cycle(struct fb_cvt_data *cvt)
+{
+	u32 c_prime = (FB_CVT_GTF_C - FB_CVT_GTF_J) *
+		(FB_CVT_GTF_K) + 256 * FB_CVT_GTF_J;
+	u32 m_prime = (FB_CVT_GTF_K * FB_CVT_GTF_M);
+	u32 h_period_est = cvt->hperiod;
+
+	return (1000 * c_prime  - ((m_prime * h_period_est)/1000))/256;
+}
+
+static u32 fb_cvt_hblank(struct fb_cvt_data *cvt)
+{
+	u32 hblank = 0;
+
+	if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK)
+		hblank = FB_CVT_RB_HBLANK;
+	else {
+		u32 ideal_duty_cycle = fb_cvt_ideal_duty_cycle(cvt);
+		u32 active_pixels = cvt->active_pixels;
+
+		if (ideal_duty_cycle < 20000)
+			hblank = (active_pixels * 20000)/
+				(100000 - 20000);
+		else {
+			hblank = (active_pixels * ideal_duty_cycle)/
+				(100000 - ideal_duty_cycle);
+		}
+	}
+
+	hblank &= ~((2 * FB_CVT_CELLSIZE) - 1);
+
+	return hblank;
+}
+
+static u32 fb_cvt_hsync(struct fb_cvt_data *cvt)
+{
+	u32 hsync;
+
+	if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK)
+		hsync = 32;
+	else
+		hsync = (FB_CVT_CELLSIZE * cvt->htotal)/100;
+
+	hsync &= ~(FB_CVT_CELLSIZE - 1);
+	return hsync;
+}
+
+static u32 fb_cvt_vbi_lines(struct fb_cvt_data *cvt)
+{
+	u32 vbi_lines, min_vbi_lines, act_vbi_lines;
+
+	if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) {
+		vbi_lines = (1000 * FB_CVT_RB_MIN_VBLANK)/cvt->hperiod + 1;
+		min_vbi_lines =  FB_CVT_RB_V_FPORCH + cvt->vsync +
+			FB_CVT_MIN_BPORCH;
+
+	} else {
+		vbi_lines = (FB_CVT_MIN_VSYNC_BP * 1000)/cvt->hperiod + 1 +
+			 FB_CVT_MIN_VPORCH;
+		min_vbi_lines = cvt->vsync + FB_CVT_MIN_BPORCH +
+			FB_CVT_MIN_VPORCH;
+	}
+
+	if (vbi_lines < min_vbi_lines)
+		act_vbi_lines = min_vbi_lines;
+	else
+		act_vbi_lines = vbi_lines;
+
+	return act_vbi_lines;
+}
+
+static u32 fb_cvt_vtotal(struct fb_cvt_data *cvt)
+{
+	u32 vtotal = cvt->yres/cvt->interlace;
+
+	vtotal += 2 * cvt->v_margin + cvt->interlace/2 + fb_cvt_vbi_lines(cvt);
+	vtotal |= cvt->interlace/2;
+
+	return vtotal;
+}
+
+static u32 fb_cvt_pixclock(struct fb_cvt_data *cvt)
+{
+	u32 pixclock;
+
+	if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK)
+		pixclock = (cvt->f_refresh * cvt->vtotal * cvt->htotal)/1000;
+	else
+		pixclock = (cvt->htotal * 1000000)/cvt->hperiod;
+
+	pixclock /= 250;
+	pixclock *= 250;
+	pixclock *= 1000;
+
+	return pixclock;
+}
+
+static u32 fb_cvt_aspect_ratio(struct fb_cvt_data *cvt)
+{
+	u32 xres = cvt->xres;
+	u32 yres = cvt->yres;
+	u32 aspect = -1;
+
+	if (xres == (yres * 4)/3 && !((yres * 4) % 3))
+		aspect = 0;
+	else if (xres == (yres * 16)/9 && !((yres * 16) % 9))
+		aspect = 1;
+	else if (xres == (yres * 16)/10 && !((yres * 16) % 10))
+		aspect = 2;
+	else if (xres == (yres * 5)/4 && !((yres * 5) % 4))
+		aspect = 3;
+	else if (xres == (yres * 15)/9 && !((yres * 15) % 9))
+		aspect = 4;
+	else {
+		printk(KERN_INFO "fbcvt: Aspect ratio not CVT "
+		       "standard\n");
+		aspect = 7;
+		cvt->status = 1;
+	}
+
+	return aspect;
+}
+
+static void fb_cvt_print_name(struct fb_cvt_data *cvt)
+{
+	u32 pixcount, pixcount_mod;
+	int cnt = 255, offset = 0, read = 0;
+	u8 *buf = kmalloc(256, GFP_KERNEL);
+
+	if (!buf)
+		return;
+
+	memset(buf, 0, 256);
+	pixcount = (cvt->xres * (cvt->yres/cvt->interlace))/1000000;
+	pixcount_mod = (cvt->xres * (cvt->yres/cvt->interlace)) % 1000000;
+	pixcount_mod /= 1000;
+
+	read = snprintf(buf+offset, cnt, "fbcvt: %dx%d@%d: CVT Name - ",
+			cvt->xres, cvt->yres, cvt->refresh);
+	offset += read;
+	cnt -= read;
+
+	if (cvt->status)
+		snprintf(buf+offset, cnt, "Not a CVT standard - %d.%03d Mega "
+			 "Pixel Image\n", pixcount, pixcount_mod);
+	else {
+		if (pixcount) {
+			read = snprintf(buf+offset, cnt, "%d", pixcount);
+			cnt -= read;
+			offset += read;
+		}
+
+		read = snprintf(buf+offset, cnt, ".%03dM", pixcount_mod);
+		cnt -= read;
+		offset += read;
+
+		if (cvt->aspect_ratio == 0)
+			read = snprintf(buf+offset, cnt, "3");
+		else if (cvt->aspect_ratio == 3)
+			read = snprintf(buf+offset, cnt, "4");
+		else if (cvt->aspect_ratio == 1 || cvt->aspect_ratio == 4)
+			read = snprintf(buf+offset, cnt, "9");
+		else if (cvt->aspect_ratio == 2)
+			read = snprintf(buf+offset, cnt, "A");
+		else
+			read = 0;
+		cnt -= read;
+		offset += read;
+
+		if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK) {
+			read = snprintf(buf+offset, cnt, "-R");
+			cnt -= read;
+			offset += read;
+		}
+	}
+
+	printk(KERN_INFO "%s\n", buf);
+	kfree(buf);
+}
+
+static void fb_cvt_convert_to_mode(struct fb_cvt_data *cvt,
+				   struct fb_videomode *mode)
+{
+	mode->refresh = cvt->f_refresh;
+	mode->pixclock = KHZ2PICOS(cvt->pixclock/1000);
+	mode->left_margin = cvt->h_front_porch;
+	mode->right_margin = cvt->h_back_porch;
+	mode->hsync_len = cvt->hsync;
+	mode->upper_margin = cvt->v_front_porch;
+	mode->lower_margin = cvt->v_back_porch;
+	mode->vsync_len = cvt->vsync;
+
+	mode->sync &= ~(FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT);
+
+	if (cvt->flags & FB_CVT_FLAG_REDUCED_BLANK)
+		mode->sync |= FB_SYNC_HOR_HIGH_ACT;
+	else
+		mode->sync |= FB_SYNC_VERT_HIGH_ACT;
+}
+
+/*
+ * fb_find_mode_cvt - calculate mode using VESA(TM) CVT
+ * @mode: pointer to fb_videomode; xres, yres, refresh and vmode must be
+ *        pre-filled with the desired values
+ * @margins: add margin to calculation (1.8% of xres and yres)
+ * @rb: compute with reduced blanking (for flatpanels)
+ *
+ * RETURNS:
+ * 0 for success
+ * @mode is filled with computed values.  If interlaced, the refresh field
+ * will be filled with the field rate (2x the frame rate)
+ *
+ * DESCRIPTION:
+ * Computes video timings using VESA(TM) Coordinated Video Timings
+ */
+int fb_find_mode_cvt(struct fb_videomode *mode, int margins, int rb)
+{
+	struct fb_cvt_data cvt;
+
+	memset(&cvt, 0, sizeof(cvt));
+
+	if (margins)
+	    cvt.flags |= FB_CVT_FLAG_MARGINS;
+
+	if (rb)
+	    cvt.flags |= FB_CVT_FLAG_REDUCED_BLANK;
+
+	if (mode->vmode & FB_VMODE_INTERLACED)
+	    cvt.flags |= FB_CVT_FLAG_INTERLACED;
+
+	cvt.xres = mode->xres;
+	cvt.yres = mode->yres;
+	cvt.refresh = mode->refresh;
+	cvt.f_refresh = cvt.refresh;
+	cvt.interlace = 1;
+
+	if (!cvt.xres || !cvt.yres || !cvt.refresh) {
+		printk(KERN_INFO "fbcvt: Invalid input parameters\n");
+		return 1;
+	}
+
+	if (!(cvt.refresh == 50 || cvt.refresh == 60 || cvt.refresh == 70 ||
+	      cvt.refresh == 85)) {
+		printk(KERN_INFO "fbcvt: Refresh rate not CVT "
+		       "standard\n");
+		cvt.status = 1;
+	}
+
+	cvt.xres &= ~(FB_CVT_CELLSIZE - 1);
+
+	if (cvt.flags & FB_CVT_FLAG_INTERLACED) {
+		cvt.interlace = 2;
+		cvt.f_refresh *= 2;
+	}
+
+	if (cvt.flags & FB_CVT_FLAG_REDUCED_BLANK) {
+		if (cvt.refresh != 60) {
+			printk(KERN_INFO "fbcvt: 60Hz refresh rate "
+			       "advised for reduced blanking\n");
+			cvt.status = 1;
+		}
+	}
+
+	if (cvt.flags & FB_CVT_FLAG_MARGINS) {
+		cvt.h_margin = (cvt.xres * 18)/1000;
+		cvt.h_margin &= ~(FB_CVT_CELLSIZE - 1);
+		cvt.v_margin = ((cvt.yres/cvt.interlace)* 18)/1000;
+	}
+
+	cvt.aspect_ratio = fb_cvt_aspect_ratio(&cvt);
+	cvt.active_pixels = cvt.xres + 2 * cvt.h_margin;
+	cvt.hperiod = fb_cvt_hperiod(&cvt);
+	cvt.vsync = fb_cvt_vbi_tab[cvt.aspect_ratio];
+	cvt.vtotal = fb_cvt_vtotal(&cvt);
+	cvt.hblank = fb_cvt_hblank(&cvt);
+	cvt.htotal = cvt.active_pixels + cvt.hblank;
+	cvt.hsync = fb_cvt_hsync(&cvt);
+	cvt.pixclock = fb_cvt_pixclock(&cvt);
+	cvt.hfreq = cvt.pixclock/cvt.htotal;
+	cvt.h_back_porch = cvt.hblank/2 + cvt.h_margin;
+	cvt.h_front_porch = cvt.hblank - cvt.hsync - cvt.h_back_porch +
+		2 * cvt.h_margin;
+	cvt.v_back_porch = 3 + cvt.v_margin;
+	cvt.v_front_porch = cvt.vtotal - cvt.yres/cvt.interlace -
+	    cvt.v_back_porch - cvt.vsync;
+	fb_cvt_print_name(&cvt);
+	fb_cvt_convert_to_mode(&cvt, mode);
+
+	return 0;
+}
+EXPORT_SYMBOL(fb_find_mode_cvt);