From: Nishanth Menon <nm@ti.com>
Date: Fri, 17 Jun 2022 18:26:11 +0000 (-0500)
Subject: board: ti: common: Handle the legacy eeprom address width properly
X-Git-Url: http://git.dujemihanovic.xyz/img/%7B%7B%20%24image.RelPermalink%20%7D%7D?a=commitdiff_plain;h=bc1de483711c30e32dffdf71574aa878c1087ed0;p=u-boot.git

board: ti: common: Handle the legacy eeprom address width properly

Due to supply chain issues, we are starting to see a mixture of eeprom
usage including the smaller 7-bit addressing eeproms such as 24c04
used for eeproms.

These eeproms don't respond well to 2 byte addressing and fail the
read operation. We do have a check to ensure that we are reading the
alternate addressing size, however the valid failure prevents us
from checking at 1 byte anymore.

Rectify the same by falling through and depend on header data comparison
to ensure that we have valid data.

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
---

diff --git a/board/ti/common/board_detect.c b/board/ti/common/board_detect.c
index 381cddc00a..0806dea11e 100644
--- a/board/ti/common/board_detect.c
+++ b/board/ti/common/board_detect.c
@@ -86,7 +86,7 @@ __weak void gpi2c_init(void)
 static int __maybe_unused ti_i2c_eeprom_get(int bus_addr, int dev_addr,
 					    u32 header, u32 size, uint8_t *ep)
 {
-	u32 hdr_read;
+	u32 hdr_read = 0xdeadbeef;
 	int rc;
 
 #if CONFIG_IS_ENABLED(DM_I2C)
@@ -107,9 +107,13 @@ static int __maybe_unused ti_i2c_eeprom_get(int bus_addr, int dev_addr,
 	if (rc)
 		return rc;
 
-	rc = dm_i2c_read(dev, 0, (uint8_t *)&hdr_read, 4);
-	if (rc)
-		return rc;
+	/*
+	 * Skip checking result here since this could be a valid i2c read fail
+	 * on some boards that use 1 byte addressing.
+	 * We must allow for fall through to check the data if 1 byte
+	 * addressing works
+	 */
+	(void)dm_i2c_read(dev, 0, (uint8_t *)&hdr_read, 4);
 
 	/* Corrupted data??? */
 	if (hdr_read != header) {
@@ -144,9 +148,13 @@ static int __maybe_unused ti_i2c_eeprom_get(int bus_addr, int dev_addr,
 	 */
 	byte = 2;
 
-	rc = i2c_read(dev_addr, 0x0, byte, (uint8_t *)&hdr_read, 4);
-	if (rc)
-		return rc;
+	/*
+	 * Skip checking result here since this could be a valid i2c read fail
+	 * on some boards that use 1 byte addressing.
+	 * We must allow for fall through to check the data if 1 byte
+	 * addressing works
+	 */
+	(void)i2c_read(dev_addr, 0x0, byte, (uint8_t *)&hdr_read, 4);
 
 	/* Corrupted data??? */
 	if (hdr_read != header) {