From 3595dfdbbdb8ad843742589ff59efa86b071075d Mon Sep 17 00:00:00 2001
From: Amy Gale Ruth Bowersox <amy@erbosoft.com>
Date: Sun, 1 Dec 2019 18:53:54 -0700
Subject: [PATCH] add framebuffer initialization

---
 src/Makefile |  2 +-
 src/fbinit.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/fbinit.h |  7 +++++
 src/main.c   |  4 +++
 4 files changed, 88 insertions(+), 1 deletion(-)
 create mode 100644 src/fbinit.c
 create mode 100644 src/fbinit.h

diff --git a/src/Makefile b/src/Makefile
index 08f0b3a..ac35150 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,4 +1,4 @@
-OBJS=main.o sysinput.o log.o gpio.o msg_queue.o time_func.o
+OBJS=main.o sysinput.o fbinit.o log.o gpio.o msg_queue.o time_func.o
 LIBS=-lbcm2835 -lpthread
 
 upiwin: $(OBJS)
diff --git a/src/fbinit.c b/src/fbinit.c
new file mode 100644
index 0000000..477dc8f
--- /dev/null
+++ b/src/fbinit.c
@@ -0,0 +1,76 @@
+#include <stddef.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <linux/fb.h>
+#include "log.h"
+#include "fbinit.h"
+
+static int fb_fd = -1;
+
+static void dump_fixed_info(const struct fb_fix_screeninfo *p)
+{
+  Log(LDEBUG, "--Fixed screen info follows--");
+  Log(LDEBUG, "ID=%s SMEM@0x%08x/%u TYPE=%u TYPEAUX=%u VIZ=%u",
+      p->id, p->smem_start, p->smem_len, p->type, p->type_aux, p->visual);
+  Log(LDEBUG, "XPAN=%u YPAN=%u YWRAP=%u LINELEN=%u", p->xpanstep, p->ypanstep, p->ywrapstep, p->line_length);
+  Log(LDEBUG, "MMIO@0x%08x/%u ACCEL=%02x CAP=%08x", p->mmio_start, p->mmio_len, p->accel, p->capabilities);
+  Log(LDEBUG, "--ends--");
+}
+
+static void dump_var_info(const struct fb_var_screeninfo *p)
+{
+  Log(LDEBUG, "--Variable screen info follows--");
+  Log(LDEBUG, "RES=(%u,%u) VRES=(%u,%u) OFS=(%u,%u) BPP=%u GS=%u", p->xres, p->yres,
+      p->xres_virtual, p->yres_virtual, p->xoffset, p->yoffset, p->bits_per_pixel, p->grayscale);
+  Log(LDEBUG, "RedBits: ofs=%u len=%u mright=%u", p->red.offset, p->red.length, p->red.msb_right);
+  Log(LDEBUG, "GreenBits: ofs=%u len=%u mright=%u", p->green.offset, p->green.length, p->green.msb_right);
+  Log(LDEBUG, "BlueBits: ofs=%u len=%u mright=%u", p->blue.offset, p->blue.length, p->blue.msb_right);
+  Log(LDEBUG, "XparBits: ofs=%u len=%u mright=%u", p->transp.offset, p->transp.length, p->transp.msb_right);
+  Log(LDEBUG, "NONSTD=%u ACTIV=%u PSIZ=(%u,%u) AFLG=%08x",
+      p->nonstd, p->activate, p->width, p->height, p->accel_flags);
+  Log(LDEBUG, "PIXCLK=%u LM=%u RM=%u TM=%u BM=%u HSYNC=%u VSYNC=%u", p->pixclock, p->left_margin, p->right_margin,
+      p->upper_margin, p->lower_margin, p->hsync_len, p->vsync_len);
+  Log(LDEBUG, "SYNC=%u VMODE=%u ROT=%u COLORSP=%u", p->sync, p->vmode, p->rotate, p->colorspace);
+  Log(LDEBUG, "--ends--");
+}
+
+int Fb_setup(void)
+{
+  struct fb_fix_screeninfo fixed;
+  struct fb_var_screeninfo var;
+  
+  fb_fd = open("/dev/fb1", O_RDWR);
+  if (fb_fd == -1)
+  {
+    Log(LFATAL, "Unable to open framebuffer (%d)", errno);
+    return -1;
+  }
+
+  if (ioctl(fb_fd, FBIOGET_FSCREENINFO, &fixed))
+  {
+    Log(LFATAL, "Could not get fixed screen info (%d)", errno);
+    return -1;
+  }
+
+  dump_fixed_info(&fixed);
+
+  if (ioctl(fb_fd, FBIOGET_VSCREENINFO, &var))
+  {
+    Log(LFATAL, "Could not get variable screen info (%d)", errno);
+    return -1;
+  }
+
+  dump_fixed_info(&var);
+
+  /* additional initialization here */
+
+  return 0;
+}
+
+void Fb_cleanup(void)
+{
+  /* additional cleanup here */
+  
+  close(fb_fd);
+}
diff --git a/src/fbinit.h b/src/fbinit.h
new file mode 100644
index 0000000..40737f3
--- /dev/null
+++ b/src/fbinit.h
@@ -0,0 +1,7 @@
+#ifndef __FBINIT_H_INCLUDED
+#define __FBINIT_H_INCLUDED
+
+extern int Fb_setup(void);
+extern void Fb_cleanup(void);
+
+#endif /* __FBINIT_H_INCLUDED */
diff --git a/src/main.c b/src/main.c
index 868fbee..f0d546f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include "gpio.h"
 #include "log.h"
+#include "fbinit.h"
 #include "time_func.h"
 #include "sysinput.h"
 
@@ -10,6 +11,9 @@ int main(int argc, char *argv[])
   MSG msg;
   
   Time_init();
+  if (Fb_setup() != 0)
+    return EXIT_FAILURE;
+  atexit(Fb_cleanup);
   if (Gpio_setup() != 0)
     return EXIT_FAILURE;
   atexit(Gpio_cleanup);