Add opaque programmer registration infrastructure

An opaque programmer does not allow direct flash access and only offers
abstract probe/read/erase/write methods.
Due to that, opaque programmers need their own infrastructure and
registration framework.

Corresponding to flashrom svn r1459.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Michael Karcher <flashrom@mkarcher.dialup.fu-berlin.de>
diff --git a/opaque.c b/opaque.c
new file mode 100644
index 0000000..13c6a09
--- /dev/null
+++ b/opaque.c
@@ -0,0 +1,99 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2011 Carl-Daniel Hailfinger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+/*
+ * Contains the opaque programmer framework.
+ * An opaque programmer is a programmer which does not provide direct access
+ * to the flash chip and which abstracts all flash chip properties into a
+ * programmer specific interface.
+ */
+
+#include <stdint.h>
+#include "flash.h"
+#include "flashchips.h"
+#include "chipdrivers.h"
+#include "programmer.h"
+
+const struct opaque_programmer opaque_programmer_none = {
+	.max_data_read = MAX_DATA_UNSPECIFIED,
+	.max_data_write = MAX_DATA_UNSPECIFIED,
+	.probe = NULL,
+	.read = NULL,
+	.write = NULL,
+	.erase = NULL,
+};
+
+const struct opaque_programmer *opaque_programmer = &opaque_programmer_none;
+
+int probe_opaque(struct flashchip *flash)
+{
+	if (!opaque_programmer->probe) {
+		msg_perr("%s called before register_opaque_programmer. "
+			 "Please report a bug at flashrom@flashrom.org\n",
+			 __func__);
+		return 0;
+	}
+
+	return opaque_programmer->probe(flash);
+}
+
+int read_opaque(struct flashchip *flash, uint8_t *buf, int start, int len)
+{
+	if (!opaque_programmer->read) {
+		msg_perr("%s called before register_opaque_programmer. "
+			 "Please report a bug at flashrom@flashrom.org\n",
+			 __func__);
+		return 1;
+	}
+	return opaque_programmer->read(flash, buf, start, len);
+}
+
+int write_opaque(struct flashchip *flash, uint8_t *buf, int start, int len)
+{
+	if (!opaque_programmer->write) {
+		msg_perr("%s called before register_opaque_programmer. "
+			 "Please report a bug at flashrom@flashrom.org\n",
+			 __func__);
+		return 1;
+	}
+	return opaque_programmer->write(flash, buf, start, len);
+}
+
+int erase_opaque(struct flashchip *flash, unsigned int blockaddr, unsigned int blocklen)
+{
+	if (!opaque_programmer->erase) {
+		msg_perr("%s called before register_opaque_programmer. "
+			 "Please report a bug at flashrom@flashrom.org\n",
+			 __func__);
+		return 1;
+	}
+	return opaque_programmer->erase(flash, blockaddr, blocklen);
+}
+
+void register_opaque_programmer(const struct opaque_programmer *pgm)
+{
+	if (!pgm->probe || !pgm->read || !pgm->write || !pgm->erase) {
+		msg_perr("%s called with one of probe/read/write/erase being "
+			 "NULL. Please report a bug at flashrom@flashrom.org\n",
+			 __func__);
+		return;
+	}
+	opaque_programmer = pgm;
+	buses_supported |= BUS_PROG;
+}