diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c
index a326cf16ca3d..2a078c69f0d2 100644
--- a/drivers/thunderbolt/eeprom.c
+++ b/drivers/thunderbolt/eeprom.c
@@ -416,7 +416,7 @@ static int tb_drom_parse_entries(struct tb_switch *sw, size_t header_size)
 		if (pos + 1 == drom_size || pos + entry->len > drom_size
 				|| !entry->len) {
 			tb_sw_warn(sw, "DROM buffer overrun\n");
-			return -EILSEQ;
+			return -EIO;
 		}
 
 		switch (entry->type) {
@@ -543,7 +543,37 @@ static int tb_drom_read_n(struct tb_switch *sw, u16 offset, u8 *val,
 	return tb_eeprom_read_n(sw, offset, val, count);
 }
 
-static int tb_drom_parse(struct tb_switch *sw)
+static int tb_drom_bit_bang(struct tb_switch *sw, u16 *size)
+{
+	int res;
+
+	res = tb_drom_read_n(sw, 14, (u8 *) size, 2);
+	if (res)
+		return res;
+	*size &= 0x3ff;
+	*size += TB_DROM_DATA_START;
+	tb_sw_dbg(sw, "reading drom (length: %#x)\n", *size);
+	if (*size < sizeof(struct tb_drom_header)) {
+		tb_sw_warn(sw, "drom too small, aborting\n");
+		return -EIO;
+	}
+
+	sw->drom = kzalloc(*size, GFP_KERNEL);
+	if (!sw->drom)
+		return -ENOMEM;
+
+	res = tb_drom_read_n(sw, 0, sw->drom, *size);
+	if (res)
+		goto err;
+
+	return 0;
+err:
+	kfree(sw->drom);
+	sw->drom = NULL;
+	return res;
+}
+
+static int tb_drom_parse_v1(struct tb_switch *sw)
 {
 	const struct tb_drom_header *header =
 		(const struct tb_drom_header *)sw->drom;
@@ -554,7 +584,7 @@ static int tb_drom_parse(struct tb_switch *sw)
 		tb_sw_warn(sw,
 			"DROM UID CRC8 mismatch (expected: %#x, got: %#x)\n",
 			header->uid_crc8, crc);
-		return -EILSEQ;
+		return -EIO;
 	}
 	if (!sw->uid)
 		sw->uid = header->uid;
@@ -588,6 +618,43 @@ static int usb4_drom_parse(struct tb_switch *sw)
 	return tb_drom_parse_entries(sw, USB4_DROM_HEADER_SIZE);
 }
 
+static int tb_drom_parse(struct tb_switch *sw, u16 *size)
+{
+	struct tb_drom_header *header = (void *) sw->drom;
+	int res;
+
+	if (header->data_len + TB_DROM_DATA_START != *size) {
+		tb_sw_warn(sw, "drom size mismatch\n");
+		goto err;
+	}
+
+	tb_sw_dbg(sw, "DROM version: %d\n", header->device_rom_revision);
+
+	switch (header->device_rom_revision) {
+	case 3:
+		res = usb4_drom_parse(sw);
+		break;
+	default:
+		tb_sw_warn(sw, "DROM device_rom_revision %#x unknown\n",
+			   header->device_rom_revision);
+		fallthrough;
+	case 1:
+		res = tb_drom_parse_v1(sw);
+		break;
+	}
+
+	if (res) {
+		tb_sw_warn(sw, "parsing DROM failed\n");
+		goto err;
+	}
+
+	return 0;
+err:
+	kfree(sw->drom);
+	sw->drom = NULL;
+	return -EIO;
+}
+
 /**
  * tb_drom_read() - Copy DROM to sw->drom and parse it
  * @sw: Router whose DROM to read and parse
@@ -601,8 +668,7 @@ static int usb4_drom_parse(struct tb_switch *sw)
 int tb_drom_read(struct tb_switch *sw)
 {
 	u16 size;
-	struct tb_drom_header *header;
-	int res, retries = 1;
+	int res;
 
 	if (sw->drom)
 		return 0;
@@ -613,11 +679,11 @@ int tb_drom_read(struct tb_switch *sw)
 		 * in a device property. Use it if available.
 		 */
 		if (tb_drom_copy_efi(sw, &size) == 0)
-			goto parse;
+			return tb_drom_parse(sw, &size);
 
 		/* Non-Apple hardware has the DROM as part of NVM */
 		if (tb_drom_copy_nvm(sw, &size) == 0)
-			goto parse;
+			return tb_drom_parse(sw, &size);
 
 		/*
 		 * USB4 hosts may support reading DROM through router
@@ -626,7 +692,7 @@ int tb_drom_read(struct tb_switch *sw)
 		if (tb_switch_is_usb4(sw)) {
 			usb4_switch_read_uid(sw, &sw->uid);
 			if (!usb4_copy_host_drom(sw, &size))
-				goto parse;
+				return tb_drom_parse(sw, &size);
 		} else {
 			/*
 			 * The root switch contains only a dummy drom
@@ -640,67 +706,12 @@ int tb_drom_read(struct tb_switch *sw)
 	}
 
 	/* We can use LC to get UUID later */
-	if (sw->cap_lc && tb_drom_copy_nvm(sw, &size) == 0)
-		goto parse;
-
-	res = tb_drom_read_n(sw, 14, (u8 *) &size, 2);
+	if (sw->cap_lc)
+		res = tb_drom_copy_nvm(sw, &size);
+	else
+		res = tb_drom_bit_bang(sw, &size);
 	if (res)
 		return res;
-	size &= 0x3ff;
-	size += TB_DROM_DATA_START;
-	tb_sw_dbg(sw, "reading drom (length: %#x)\n", size);
-	if (size < sizeof(*header)) {
-		tb_sw_warn(sw, "drom too small, aborting\n");
-		return -EIO;
-	}
-
-	sw->drom = kzalloc(size, GFP_KERNEL);
-	if (!sw->drom)
-		return -ENOMEM;
-read:
-	res = tb_drom_read_n(sw, 0, sw->drom, size);
-	if (res)
-		goto err;
-
-parse:
-	header = (void *) sw->drom;
-
-	if (header->data_len + TB_DROM_DATA_START != size) {
-		tb_sw_warn(sw, "drom size mismatch\n");
-		if (retries--) {
-			msleep(100);
-			goto read;
-		}
-		goto err;
-	}
-
-	tb_sw_dbg(sw, "DROM version: %d\n", header->device_rom_revision);
-
-	switch (header->device_rom_revision) {
-	case 3:
-		res = usb4_drom_parse(sw);
-		break;
-	default:
-		tb_sw_warn(sw, "DROM device_rom_revision %#x unknown\n",
-			   header->device_rom_revision);
-		fallthrough;
-	case 1:
-		res = tb_drom_parse(sw);
-		break;
-	}
-
-	/* If the DROM parsing fails, wait a moment and retry once */
-	if (res == -EILSEQ && retries--) {
-		tb_sw_warn(sw, "parsing DROM failed\n");
-		msleep(100);
-		goto read;
-	}
 
-	if (!res)
-		return 0;
-
-err:
-	kfree(sw->drom);
-	sw->drom = NULL;
-	return -EIO;
+	return tb_drom_parse(sw, &size);
 }
