Change in flashrom[master]: flashrom.c: Validate BUS before trying 4BA commands

[Edward O'Callaghan (Code Review)]

Edward O'Callaghan has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/64371 )

Change subject: flashrom.c: Validate BUS before trying 4BA commands
......................................................................

flashrom.c: Validate BUS before trying 4BA commands

4BA is sort of broken for opaque masters.

Instead of just leaning on the chip feature flag to determine when to
enter_exit out of 4ba modes, validate '(flash->chip->bustype == BUS_SPI)'.
The following chips;
     - GD25Q256D
     - MX25L25635F/MX25L25645G
     - W25Q256.V
     - W25Q256JV_M
Have issue with opaque masters that tries incorrectly
to issue 4BA commands which results in failure.

Change-Id: Ie26732b03a67bfafc8eae1f642dc85c6d37f7772
Signed-off-by: Edward O'Callaghan 
---
M flashrom.c
1 file changed, 2 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/71/64371/1

diff --git a/flashrom.c b/flashrom.c
index 7f54488..356de79 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -1845,7 +1845,8 @@
    }

/* Enable/disable 4-byte addressing mode if flash chip supports it */
-	if (flash->chip->feature_bits & (FEATURE_4BA_ENTER | FEATURE_4BA_ENTER_WREN | FEATURE_4BA_ENTER_EAR7)) {
+	if ((flash->chip->bustype == BUS_SPI) &&
+	    (flash->chip->feature_bits & (FEATURE_4BA_ENTER | FEATURE_4BA_ENTER_WREN | FEATURE_4BA_ENTER_EAR7))) {
    	int ret;
    	if (spi_master_4ba(flash))
    		ret = spi_enter_4ba(flash);