Some improvements at the building system

From: Mauro Carvalho Chehab <mchehab@infradead.org>

Building system now looks kernel config.h and autoconf.h files, 
seeking for the compiled options at kernel. If something is missing,
it will disable compilation for that driver, printing a warning message.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

4 files changed, 162 insertions, 34 deletions

diff --git a/v4l/Makefile b/v4l/Makefile
index 58354a035..881329d7d 100644
--- a/v4l/Makefile
+++ b/v4l/Makefile
@@ -17,7 +17,12 @@ else
 ifneq ($(SRCDIR),)
 KDIR := $(SRCDIR)
 else
+ifneq ($(KERNELRELEASE),)
 KDIR := /lib/modules/$(KERNELRELEASE)/build
+else
+KDIR := /lib/modules/$(shell uname -r|perl -ne 'if (/^([0-9]*)\.([0-9])*\.([0-9]*)(.*)$$/) { printf ("%s.%s.%s%s\n",$$1,$$2,$$3,$$4); };')/build
+
+endif
 endif
 
 endif
@@ -133,9 +138,6 @@ remove rminstall:: media-rminstall ivtv-rminstall
 #################################################
 # Compiling preparation rules
 
-Makefile.media:: .version
-	scripts/make_makefile.pl
-
 .version::
 ifneq ($(KERNELRELEASE),)
 	@echo -e VERSION=$(VERSION)\\nPATCHLEVEL:=$(PATCHLEVEL)\\nSUBLEVEL:=$(SUBLEVEL)\\nKERNELRELEASE:=$(KERNELRELEASE) > $(obj)/.version
@@ -147,6 +149,9 @@ else
 	@uname -r|perl -ne 'if (/^([0-9]*)\.([0-9])*\.([0-9]*)(.*)$$/) { printf ("VERSION=%s\nPATCHLEVEL:=%s\nSUBLEVEL:=%s\nKERNELRELEASE:=%s.%s.%s%s\n",$$1,$$2,$$3,$$1,$$2,$$3,$$4); };' > $(obj)/.version
 endif
 
+Makefile.media:: .version
+	scripts/make_makefile.pl $(KDIR)
+
 release::
 ifneq ($(VER),)
 	@echo "Forcing compiling to version $(VER)."
@@ -180,9 +185,7 @@ links::
 	@find ../linux/drivers/media -name '*.[ch]' -type f -exec ln -sf '{}' . \;
 	@find ../linux/sound -name '*.[ch]' -type f -exec ln -sf '{}' . \;
 
-config-compat.h::
-	scripts/make_myconfig.pl
-
+config-compat.h:: .myconfig
 	@echo \#ifndef __CONFIG_COMPAT_H__ > config-compat.h
 	@echo \#define __CONFIG_COMPAT_H__ >> config-compat.h
 	@echo >> config-compat.h
@@ -253,29 +256,27 @@ LXDIALOG_DIR := $(shell if [ -d $(KDIR)/scripts/kconfig/lxdialog ]; then echo kc
 LXDIALOG_LNK := $(if $(LXDIALOG_DIR),scripts/kconfig,scripts/lxdialog)
 LXDIALOG := $(KDIR)/scripts/$(LXDIALOG_DIR)lxdialog/lxdialog
 
+.myconfig : .config
+	./scripts/make_myconfig.pl
+
 xconfig:: links .version $(QCONF)
-	./scripts/make_kconfig.pl
+	./scripts/make_kconfig.pl $(KDIR)
 	$(QCONF) Kconfig
-	./scripts/make_myconfig.pl
 
 gconfig:: links .version $(GCONF)
-	./scripts/make_kconfig.pl
+	./scripts/make_kconfig.pl $(KDIR)
 	$(QCONF) Kconfig
-	./scripts/make_myconfig.pl
 
 config:: links .version $(CONF)
-	./scripts/make_kconfig.pl
+	./scripts/make_kconfig.pl $(KDIR)
 	$(CONF) Kconfig
-	./scripts/make_myconfig.pl
 
 menuconfig:: links .version $(MCONF) lxdialog
-	./scripts/make_kconfig.pl
+	./scripts/make_kconfig.pl $(KDIR)
 	$(MCONF) Kconfig
-	./scripts/make_myconfig.pl
 
 allyesconfig allmodconfig:: links .version
-	./scripts/make_kconfig.pl 1
-	./scripts/make_myconfig.pl
+	./scripts/make_kconfig.pl $(KDIR) 1
 
 # rule to build kernel conf programs
 KMAKEVARS := config-targets=1 mixed-targets=0 dot-config=0
diff --git a/v4l/scripts/make_kconfig.pl b/v4l/scripts/make_kconfig.pl
index b499fefa1..33a53d772 100755
--- a/v4l/scripts/make_kconfig.pl
+++ b/v4l/scripts/make_kconfig.pl
@@ -7,10 +7,69 @@ my %config = ();
 my %intopt = ();
 my %hexopt = ();
 my %tristate = ();
+my %kernopts = ();
+my %depmods = ();
 my $version, $level, $sublevel;
 
+my $kernel=shift;
 my $force_kconfig=shift;
 
+#!/usr/bin/perl
+use FileHandle;
+
+###########################################################
+# Checks config.h and autoconf.h for current kernel defines
+sub process_config ($)
+{
+	my $filename = shift;
+        my $in = new FileHandle;
+
+	open $in,"$kernel/include/$filename" or die;
+	while (<$in>) {
+	        if (m|\#include\s+\<(.*)\>|) {
+			process_config ($1);
+			next;
+	        }
+		if (m/\#define\s+CONFIG_([^ ]*)_ON_SMP\s+(.*)\n/) {
+			my $key=$1;
+			my $value=$2;
+#			printf "defined $key as $value\n";
+			if ( $value == 1 ) {
+				$value='y';
+			}
+			$kernopts{$key}=$value;
+			next;
+		}
+		if (m/\#define\s+CONFIG_([^ ]*)_MODULE\s+(.*)\n/) {
+			my $key=$1;
+			my $value=$2;
+#			printf "defined $key as $value\n";
+			if ( $value == 1 ) {
+				$value='m';
+			}
+			$kernopts{$key}=$value;
+			next;
+		}
+		if (m/\#define\s+CONFIG_([^ ]*)\s+(.*)\n/) {
+			my $key=$1;
+			my $value=$2;
+#			printf "defined $key as $value\n";
+			if ( $value == 1 ) {
+				$value='y';
+			}
+			$kernopts{$key}=$value;
+			next;
+		}
+		if (m/\#undef\s+CONFIG_([^ ]*)\n/) {
+#			printf "undefined $1\n";
+			$kernopts{$1}='n';
+			next;
+		}
+	}
+
+	close $in;
+}
+
 sub add_bool($)
 {
 	my $arg=shift;
@@ -18,6 +77,8 @@ sub add_bool($)
 	exists $config{$arg} or die "Adding unknown boolean '$arg'";
 	$tristate{$arg}="bool";
 #	printf "Boolean:%s\n",$arg;
+
+	$kernopts{$arg}='y';
 }
 
 sub add_tristate($)
@@ -26,7 +87,8 @@ sub add_tristate($)
 
 	exists $config{$arg} or die "Adding unknown tristate '$arg'";
 	$tristate{$arg}="tristate";
-#	printf "Tristate:%s\n",$arg;
+
+	$kernopts{$arg}='m';
 }
 
 sub add_int($)
@@ -75,6 +137,7 @@ sub add_config($)
 	}
 }
 
+########################################
 # Turn option off, iff it already exists
 sub disable_config($)
 {
@@ -83,9 +146,14 @@ sub disable_config($)
 	$config{$key} = 0 if (exists $config{$key});
 }
 
-sub check_deps($)
+#################################################################
+# Make a list of dependencies and the number of references for it
+sub check_deps($$)
 {
+	my $key=shift;
 	my $arg=shift;
+
+	$depmods{$key}=$arg;
 	$arg=$arg." ";
 
 	while ($arg ne "") {
@@ -96,6 +164,44 @@ sub check_deps($)
 		}
 		$arg =~ s/^[^ ]+ //;
 	}
+
+	return $ok;
+}
+
+######################################################
+# Checks if all dependencies for the key are satisfied
+sub deps_ok($)
+{
+	my $key=shift;
+	my $arg=$depmods{$key};
+	my $ok=1;
+
+	if ($arg eq "") {
+		return $ok;
+	}
+
+	$arg=$arg." ";
+
+
+#	printf "$key: deps are '$arg'\n";
+
+	while ($arg ne "") {
+		if ($arg =~ m/^([A-Z0-9_]+) /) {
+			if ((! exists $kernopts {$1}) || ($kernopts {$1} eq 'n')) {
+				printf "$key: Required kernel opt '$1' is not present\n";
+				$ok=0;
+			}
+		}
+		if ($arg =~ m/^\!([A-Z0-9_]+) /) {
+			if ($kernopts {$1} eq 'y') {
+				printf "$key: Driver is incompatible with  '$1'\n";
+				$ok=0;
+			}
+		}
+		$arg =~ s/^[^ ]+ //;
+	}
+
+	return $ok;
 }
 
 sub open_kconfig($$) {
@@ -105,7 +211,7 @@ sub open_kconfig($$) {
 	my $key;
 
 #print "opening $file\n";
-	open $in,"$file";
+	open $in,"$file" or die;
 	while (<$in>) {
 #		if (m;^\s*source[\s\"]+drivers/media/(video|dvb)/Kconfig;) {
 #			next;
@@ -124,10 +230,10 @@ sub open_kconfig($$) {
 			next;
 		}
 		if (m|^\s+depends on\s+(.*)\n|) {
-			check_deps ($1);
+			check_deps ($key,$1);
 		}
 		if (m|^\s+select\s+(.*)\n|) {
-			check_deps ($1);
+			check_deps ($key,$1);
 		}
 		if (m|^\s+bool(ean)?\s|) {
 			add_bool($key);
@@ -155,7 +261,6 @@ sub open_kconfig($$) {
 			$default_seen = 1;
 			$_ = "\tdefault n\n";
 		}
-
 		# check for end of config definition for disabled drivers
 		# we need to make sure we've disabled it, and add a bit
 		# to the help text
@@ -211,7 +316,7 @@ sub parse_versions ()
 	my $in = new FileHandle;
 	my $ver;
 
-	open $in,"versions.txt";
+	open $in,"versions.txt" or die;
 	while (<$in>) {
 		if (m/\[([\d.]*)\]/) {
 			$ver=$1;
@@ -226,9 +331,11 @@ sub parse_versions ()
 	close $in;
 }
 
+process_config("linux/config.h");
+
 parse_versions;
 
-open IN,".version";
+open IN,".version" or die;
 while (<IN>) {
 	if (m/KERNELRELEASE\s*[:]*[=]+\s*(\d+)\.(\d+)\.(\d+)/) {
 		$version=$1;
@@ -240,7 +347,7 @@ close IN;
 
 printf "Preparing to compile for kernel version %d.%d.%d\n",$version,$level,$sublevel;
 
-open OUT,">Kconfig";
+open OUT,">Kconfig" or die;
 
 print OUT <<"EOF";
 mainmenu "V4L/DVB menu"
@@ -273,14 +380,19 @@ while ( my ($key, $value) = each(%config) ) {
 		delete $depend{$key};
 }
 
-open OUT,">Kconfig.kern";
+open OUT,">Kconfig.kern" or die;
 
 print OUT "config MODULES\n\tboolean\n\tdefault y\n\n";
 add_config('MODULES');
 add_bool('MODULES');
 
 while ( my ($key, $value) = each(%depend) ) {
-	print OUT "# $key with $value refs\nconfig $key\n\ttristate\n\tdefault m\n\n";
+	if ($kernopts{$key}) {
+		print OUT "# $key with $value refs\nconfig $key\n\ttristate\n\tdefault ".
+			$kernopts{$key}."\n\n";
+	} else {
+		print OUT "# $key with $value refs\nconfig $key\n\ttristate\n\tdefault n #not found\n\n";
+	}
 }
 close OUT;
 
@@ -290,10 +402,24 @@ disable_config('DVB_CINERGYT2_TUNING');
 
 # Produce a .config file if it's forced or one doesn't already exist
 if (($force_kconfig eq 1) || !open IN,".config") {
-	open OUT,">.config";
+	open OUT,">.config" or die;
 	while ( my ($key,$value) = each(%tristate) ) {
 		if (!$config{$key}) {
-			print OUT "CONFIG_$key=n\n";
+			print OUT "# CONFIG_$key is not set\n";
+		} elsif ($kernopts{$key}) {
+			my $ok=deps_ok($key);
+
+			# If deps are not ok, mark default as n
+			if (!$ok) {
+#				print "$key disabled due to missing kernel required prereq\n";
+				$kernopts{$key}='n';
+			}
+
+			if ($kernopts{$key} eq 'n') {
+				print OUT "# CONFIG_$key is not set\n";
+			} else {
+				print OUT "CONFIG_$key=".$kernopts{$key}."\n";
+			}
 		} elsif ($value eq 'tristate') {
 			print OUT "CONFIG_$key=m\n";
 		} else { # must be 'bool'
diff --git a/v4l/scripts/make_makefile.pl b/v4l/scripts/make_makefile.pl
index f0d9aef7f..e0a099e9b 100755
--- a/v4l/scripts/make_makefile.pl
+++ b/v4l/scripts/make_makefile.pl
@@ -1,6 +1,7 @@
 #!/usr/bin/perl
 use FileHandle;
 
+my $kernel=shift;
 my $instdir = ();
 
 sub check_line($$$)
@@ -181,5 +182,5 @@ if (open IN,"Makefile.media") {
 if (open IN,".myconfig") {
 	close IN;
 } else {
-	system "./scripts/make_kconfig.pl 1";
+	system "./scripts/make_kconfig.pl $kernel 1";
 }
diff --git a/v4l/versions.txt b/v4l/versions.txt
index 35cb44fc6..6da410612 100644
--- a/v4l/versions.txt
+++ b/v4l/versions.txt
@@ -6,10 +6,6 @@ VIDEO_ZR36120
 # This is also marked as broken
 VIDEO_PLANB
 
-# Those are architecture-dependent
-VIDEO_VINO
-VIDEO_M32R_AR_M64278
-
 [2.6.16]
 VIDEO_USBVIDEO
 USB_VICAM
@@ -23,6 +19,10 @@ USB_ZC0301
 VIDEO_ZORAN_AVS6EYES
 VIDEO_TLV320AIC23B
 
+# Those are architecture-dependent
+VIDEO_VINO
+VIDEO_M32R_AR_M64278
+
 [2.6.14]
 VIDEO_ZORAN
 VIDEO_ZORAN_BUZ