[flashrom-gerrit] Change in flashrom[master]: Subject: raiden_debug_spi.c: Disable USB retry during some error codes

[Brian Nemec (Code Review)]

Hello Brian Nemec,

I'd like you to do a code review. Please visit

https://review.coreboot.org/c/flashrom/+/41152

to review the following change.

Change subject: Subject: raiden_debug_spi.c: Disable USB retry during some error codes
......................................................................

Subject: raiden_debug_spi.c: Disable USB retry during some error codes

Enables the USB SPI transfer retry mechanism when the write count
error code is returned. This error code can indicate a recoverable
transfer failure.

BUG=b:153887087
BRANCH=none
TEST=Manual testing of ServoMicro and Flashrom when performing
    reads, writes, and verifications of the EC firmware on Nami.
TEST=Modified servo micro to produce periodic errors when reading
    the packet length to verify the recovery is successful.

Change-Id: I9e6b2ccec0b06aab0d6920f1bddf108058e5d6b1
---
M raiden_debug_spi.c
1 file changed, 7 insertions(+), 3 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/52/41152/1

diff --git a/raiden_debug_spi.c b/raiden_debug_spi.c
index 2127f69..ac74c0b 100644
--- a/raiden_debug_spi.c
+++ b/raiden_debug_spi.c
@@ -188,9 +188,13 @@
 static bool retry_recovery(int error_code)
 {
    if (error_code < 0x10000) {
-		/* Handle error codes returned from the device. */
-		if (USB_SPI_WRITE_COUNT_INVALID <= error_code &&
-			error_code <= USB_SPI_DISABLED) {
+		/*
+		 * Handle error codes returned from the device. USB_SPI_TIMEOUT,
+		 * USB_SPI_BUSY, and USB_SPI_WRITE_COUNT_INVALID have been observed
+		 * during transfer errors to the device and can be recovered.
+		 */
+		if (USB_SPI_READ_COUNT_INVALID <= error_code &&
+		    error_code <= USB_SPI_DISABLED) {
    		return false;
    	}
    } else if (usb_device_is_libusb_error(error_code)) {