From 4a904c98335b9e0ee322d271585cc04bd334f803 Mon Sep 17 00:00:00 2001
From: Ali Gholami Rudi <ali@rudi.ir>
Date: Mon, 22 Dec 2014 15:31:12 +0330
Subject: [PATCH] draw: clean up draw.h interface

The changes are as follows: fb_init() takes the framebuffer device
as an argument, fb_set() is no longer defined in draw.c, and the order
of framebuffer colors are included in fb_mode().
---
 config.h |  3 +++
 draw.c   | 36 ++++++++++++++++--------------------
 draw.h   | 13 +++++--------
 pad.c    |  8 +++++++-
 4 files changed, 31 insertions(+), 29 deletions(-)

diff --git a/config.h b/config.h
index 99c3472..064e797 100644
--- a/config.h
+++ b/config.h
@@ -1,3 +1,6 @@
+/* framebuffer device */
+#define FBDEV		"/dev/fb0"
+
 /* list of tags */
 #define TAGS		"xnlhtr01uiva-"
 #define TAGS_SAVED	""
diff --git a/draw.c b/draw.c
index 15e61a7..e016220 100644
--- a/draw.c
+++ b/draw.c
@@ -2,23 +2,23 @@
 #include <linux/fb.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <unistd.h>
-#include <string.h>
 #include "draw.h"
 
 #define MIN(a, b)	((a) < (b) ? (a) : (b))
 #define MAX(a, b)	((a) > (b) ? (a) : (b))
 #define NLEVELS		(1 << 8)
 
-static int fd;
-static void *fb;
-static struct fb_var_screeninfo vinfo;
-static struct fb_fix_screeninfo finfo;
-static int bpp;
-static int nr, ng, nb;
-static int rl, rr, gl, gr, bl, br;	/* fb_color() shifts */
+static struct fb_var_screeninfo vinfo;	/* linux-specific FB structure */
+static struct fb_fix_screeninfo finfo;	/* linux-specific FB structure */
+static int fd;				/* FB device file descriptor */
+static void *fb;			/* mmap()ed FB memory */
+static int bpp;				/* bytes per pixel */
+static int nr, ng, nb;			/* color levels */
+static int rl, rr, gl, gr, bl, br;	/* shifts per color */
 
 static int fb_len(void)
 {
@@ -67,7 +67,8 @@ void fb_cmap(void)
 
 unsigned fb_mode(void)
 {
-	return (bpp << 16) | (vinfo.red.length << 8) |
+	return ((rl < gl) << 22) | ((rl < bl) << 21) | ((gl < bl) << 20) |
+		(bpp << 16) | (vinfo.red.length << 8) |
 		(vinfo.green.length << 4) | (vinfo.blue.length);
 }
 
@@ -84,14 +85,14 @@ static void init_colors(void)
 	bl = vinfo.blue.offset;
 }
 
-int fb_init(void)
+int fb_init(char *dev)
 {
-	fd = open(FBDEV_PATH, O_RDWR);
-	if (fd == -1)
+	fd = open(dev, O_RDWR);
+	if (fd < 0)
 		goto failed;
-	if (ioctl(fd, FBIOGET_VSCREENINFO, &vinfo) == -1)
+	if (ioctl(fd, FBIOGET_VSCREENINFO, &vinfo) < 0)
 		goto failed;
-	if (ioctl(fd, FBIOGET_FSCREENINFO, &finfo) == -1)
+	if (ioctl(fd, FBIOGET_FSCREENINFO, &finfo) < 0)
 		goto failed;
 	fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
 	bpp = (vinfo.bits_per_pixel + 7) >> 3;
@@ -127,12 +128,7 @@ int fb_cols(void)
 
 void *fb_mem(int r)
 {
-	return fb + (r + vinfo.yoffset) * finfo.line_length;
-}
-
-void fb_set(int r, int c, void *mem, int len)
-{
-	memcpy(fb_mem(r) + (c + vinfo.xoffset) * bpp, mem, len * bpp);
+	return fb + (r + vinfo.yoffset) * finfo.line_length + vinfo.xoffset * bpp;
 }
 
 unsigned fb_val(int r, int g, int b)
diff --git a/draw.h b/draw.h
index 4cdd476..ad8886a 100644
--- a/draw.h
+++ b/draw.h
@@ -1,19 +1,16 @@
-/* framebuffer device */
-#define FBDEV_PATH	"/dev/fb0"
+/* fbpad's framebuffer interface */
 
 /* fb_mode() interpretation */
-#define FBM_BPP(m)	(((m) >> 16) & 0x0f)
-#define FBM_COLORS(m)	((m) & 0x0fff)
+#define FBM_BPP(m)	(((m) >> 16) & 0x0f)	/* bytes per pixel (4 bits) */
+#define FBM_CLR(m)	((m) & 0x0fff)		/* bits per color (12 bits) */
+#define FBM_ORD(m)	(((m) >> 20) & 0x07)	/* color order (3 bits) */
 
 /* main functions */
-int fb_init(void);
+int fb_init(char *dev);
 void fb_free(void);
 unsigned fb_mode(void);
 void *fb_mem(int r);
 int fb_rows(void);
 int fb_cols(void);
 void fb_cmap(void);
-
-/* helper functions */
-void fb_set(int r, int c, void *mem, int len);
 unsigned fb_val(int r, int g, int b);
diff --git a/pad.c b/pad.c
index f5a356f..25bbfaf 100644
--- a/pad.c
+++ b/pad.c
@@ -18,7 +18,7 @@ static struct font *fonts[3];
 int pad_init(void)
 {
 	int r, g, b;
-	if (fb_init())
+	if (fb_init(FBDEV))
 		return 1;
 	if (sizeof(fbval_t) != FBM_BPP(fb_mode())) {
 		fprintf(stderr, "pad_init: fbval_t doesn't match fb depth\n");
@@ -137,6 +137,12 @@ static fbval_t *ch2fb(int fn, int c, short fg, short bg)
 	return fbbits;
 }
 
+static void fb_set(int r, int c, void *mem, int len)
+{
+	int bpp = FBM_BPP(fb_mode());
+	memcpy(fb_mem(r) + c * bpp, mem, len * bpp);
+}
+
 static void fb_box(int sr, int er, int sc, int ec, fbval_t val)
 {
 	static fbval_t line[32 * NCOLS];
-- 
2.11.4.GIT