[PATCH 2/3] add check_block_erasers which returns the number of well-defined erasers for a chip

[Stefan Tauner]

This can be used in various situations (including one in the upcoming SFDP patch) and
removes one FIXME in current HEAD. Needed to move check_block_eraser (which checks a
single eraser) up to avoid (upcoming) forward declaration(s).

Signed-off-by: Stefan Tauner 
---
 flashrom.c |   70 ++++++++++++++++++++++++++++++++++-------------------------
 1 files changed, 40 insertions(+), 30 deletions(-)

diff --git a/flashrom.c b/flashrom.c
index 6979d84..aed10aa 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -711,6 +711,43 @@ char *extract_programmer_param(char *param_name)
    return extract_param(&programmer_param, param_name, ",");
 }

+static int check_block_eraser(const struct flashchip *flash, int k, int log)
+{
+	struct block_eraser eraser = flash->block_erasers[k];
+
+	if (!eraser.block_erase && !eraser.eraseblocks[0].count) {
+		if (log)
+			msg_cdbg("not defined. ");
+		return 1;
+	}
+	if (!eraser.block_erase && eraser.eraseblocks[0].count) {
+		if (log)
+			msg_cdbg("eraseblock layout is known, but matching "
+				 "block erase function is not implemented. ");
+		return 1;
+	}
+	if (eraser.block_erase && !eraser.eraseblocks[0].count) {
+		if (log)
+			msg_cdbg("block erase function found, but "
+				 "eraseblock layout is not defined. ");
+		return 1;
+	}
+	return 0;
+}
+
+/* Returns the number of well-defined erasers for a chip.
+ * The log parameter controls output. */
+static int check_block_erasers(const struct flashchip *flash, int log)
+{
+	int usable_erasefunctions = 0;
+	int k;
+	for (k = 0; k < NUM_ERASEFUNCTIONS; k++) {
+		if (!check_block_eraser(flash, k, 0))
+			usable_erasefunctions++;
+	}
+	return usable_erasefunctions;
+}
+
 /* start is an offset to the base address of the flash chip */
 int check_erased_range(struct flashchip *flash, int start, int len)
 {
@@ -1462,40 +1499,13 @@ static int walk_eraseregions(struct flashchip *flash, int erasefunction,
    return 0;
 }

-static int check_block_eraser(struct flashchip *flash, int k, int log)
-{
-	struct block_eraser eraser = flash->block_erasers[k];
-
-	if (!eraser.block_erase && !eraser.eraseblocks[0].count) {
-		if (log)
-			msg_cdbg("not defined. ");
-		return 1;
-	}
-	if (!eraser.block_erase && eraser.eraseblocks[0].count) {
-		if (log)
-			msg_cdbg("eraseblock layout is known, but matching "
-				 "block erase function is not implemented. ");
-		return 1;
-	}
-	if (eraser.block_erase && !eraser.eraseblocks[0].count) {
-		if (log)
-			msg_cdbg("block erase function found, but "
-				 "eraseblock layout is not defined. ");
-		return 1;
-	}
-	return 0;
-}
-
 int erase_and_write_flash(struct flashchip *flash, uint8_t *oldcontents, uint8_t *newcontents)
 {
    int k, ret = 0;
    uint8_t *curcontents;
    unsigned long size = flash->total_size * 1024;
-	int usable_erasefunctions = 0;
+	int usable_erasefunctions = check_block_erasers(flash, 0);

-	for (k = 0; k < NUM_ERASEFUNCTIONS; k++)
-		if (!check_block_eraser(flash, k, 0))
-			usable_erasefunctions++;
    msg_cinfo("Erasing and writing flash chip... ");
    if (!usable_erasefunctions) {
    	msg_cerr("ERROR: flashrom has no erase function for this flash "
@@ -1814,13 +1824,13 @@ int chip_safety_check(struct flashchip *flash, int force, int read_it, int write
    }
    if (erase_it || write_it) {
    	/* Write needs erase. */
-		if (flash->tested & TEST_BAD_ERASE) {
+		if (flash->tested & TEST_BAD_ERASE &&
+		    !check_block_erasers(flash, 0)) {
    		msg_cerr("Erase is not working on this chip. ");
    		if (!force)
    			return 1;
    		msg_cerr("Continuing anyway.\n");
    	}
-		/* FIXME: Check if at least one erase function exists. */
    }
    if (write_it) {
    	if (flash->tested & TEST_BAD_WRITE) {