Add support for the Eon EN29LV640B chip

This chip needs special command sequences in 8 bit mode. Also, 8 bit
programming needs actually 16bit double byte program.

The chip is found on the Bifferos Bifferboard, for example.

Corresponding to flashrom svn r1521.

Signed-off-by: Rudolf Marek <r.marek@assembler.cz>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>
diff --git a/chipdrivers.h b/chipdrivers.h
index bd81098..e3eb978 100644
--- a/chipdrivers.h
+++ b/chipdrivers.h
@@ -157,4 +157,10 @@
 int erase_sector_stm50flw0x0x(struct flashctx *flash, unsigned int block, unsigned int blocksize);
 int unlock_stm50flw0x0x(struct flashctx *flash);
 
+/* en29lv640b.c */
+int probe_en29lv640b(struct flashctx *flash);
+int block_erase_en29lv640b(struct flashctx *flash, unsigned int start, unsigned int len);
+int block_erase_chip_en29lv640b(struct flashctx *flash, unsigned int start, unsigned int len);
+int write_en29lv640b(struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len);
+
 #endif /* !__CHIPDRIVERS_H__ */