[PATCH AUTOSEL 5.13 138/189] rtl8xxxu: Fix device info for RTL8192EU devices

Sasha Levin
2021-07-06T11:24:17Z

From: Pascal Terjan <pterjan@google.com>

[ Upstream commit c240b044edefa3c3af4014a4030e017dd95b59a1 ]

Based on 2001:3319 and 2357:0109 which I used to test the fix and
0bda:818b and 2357:0108 for which I found efuse dumps online.

== 2357:0109 ==
=== Before ===
Vendor: Realtek
Product: \x03802.11n NI
Serial:
=== After ===
Vendor: Realtek
Product: 802.11n NIC
Serial not available.

== 2001:3319 ==
=== Before ===
Vendor: Realtek
Product: Wireless N
Serial: no USB Adap
=== After ===
Vendor: Realtek
Product: Wireless N Nano USB Adapter
Serial not available.

Signed-off-by: Pascal Terjan <pterjan@google.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210424172959.1559890-1-pterjan@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../net/wireless/realtek/rtl8xxxu/rtl8xxxu.h | 11 +---
.../realtek/rtl8xxxu/rtl8xxxu_8192e.c | 59 +++++++++++++++++--
2 files changed, 56 insertions(+), 14 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h
index d1a566cc0c9e..01735776345a 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h
@@ -853,15 +853,10 @@ struct rtl8192eu_efuse {
u8 usb_optional_function;
u8 res9[2];
u8 mac_addr[ETH_ALEN]; /* 0xd7 */
- u8 res10[2];
- u8 vendor_name[7];
- u8 res11[2];
- u8 device_name[0x0b]; /* 0xe8 */
- u8 res12[2];
- u8 serial[0x0b]; /* 0xf5 */
- u8 res13[0x30];
+ u8 device_info[80];
+ u8 res11[3];
u8 unknown[0x0d]; /* 0x130 */
- u8 res14[0xc3];
+ u8 res12[0xc3];
};

struct rtl8xxxu_reg8val {
diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c
index cfe2dfdae928..b06508d0cdf8 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c
@@ -554,9 +554,43 @@ rtl8192e_set_tx_power(struct rtl8xxxu_priv *priv, int channel, bool ht40)
}
}

+static void rtl8192eu_log_next_device_info(struct rtl8xxxu_priv *priv,
+ char *record_name,
+ char *device_info,
+ unsigned int *record_offset)
+{
+ char *record = device_info + *record_offset;
+
+ /* A record is [ total length | 0x03 | value ] */
+ unsigned char l = record[0];
+
+ /*
+ * The whole device info section seems to be 80 characters, make sure
+ * we don't read further.
+ */
+ if (*record_offset + l > 80) {
+ dev_warn(&priv->udev->dev,
+ "invalid record length %d while parsing \"%s\" at offset %u.\n",
+ l, record_name, *record_offset);
+ return;
+ }
+
+ if (l >= 2) {
+ char value[80];
+
+ memcpy(value, &record[2], l - 2);
+ value[l - 2] = '\0';
+ dev_info(&priv->udev->dev, "%s: %s\n", record_name, value);
+ *record_offset = *record_offset + l;
+ } else {
+ dev_info(&priv->udev->dev, "%s not available.\n", record_name);
+ }
+}
+
static int rtl8192eu_parse_efuse(struct rtl8xxxu_priv *priv)
{
struct rtl8192eu_efuse *efuse = &priv->efuse_wifi.efuse8192eu;
+ unsigned int record_offset;
int i;

if (efuse->rtl_id != cpu_to_le16(0x8129))
@@ -604,12 +638,25 @@ static int rtl8192eu_parse_efuse(struct rtl8xxxu_priv *priv)
priv->has_xtalk = 1;
priv->xtalk = priv->efuse_wifi.efuse8192eu.xtal_k & 0x3f;

- dev_info(&priv->udev->dev, "Vendor: %.7s\n", efuse->vendor_name);
- dev_info(&priv->udev->dev, "Product: %.11s\n", efuse->device_name);
- if (memchr_inv(efuse->serial, 0xff, 11))
- dev_info(&priv->udev->dev, "Serial: %.11s\n", efuse->serial);
- else
- dev_info(&priv->udev->dev, "Serial not available.\n");
+ /*
+ * device_info section seems to be laid out as records
+ * [ total length | 0x03 | value ] so:
+ * - vendor length + 2
+ * - 0x03
+ * - vendor string (not null terminated)
+ * - product length + 2
+ * - 0x03
+ * - product string (not null terminated)
+ * Then there is one or 2 0x00 on all the 4 devices I own or found
+ * dumped online.
+ * As previous version of the code handled an optional serial
+ * string, I now assume there may be a third record if the
+ * length is not 0.
+ */
+ record_offset = 0;
+ rtl8192eu_log_next_device_info(priv, "Vendor", efuse->device_info, &record_offset);
+ rtl8192eu_log_next_device_info(priv, "Product", efuse->device_info, &record_offset);
+ rtl8192eu_log_next_device_info(priv, "Serial", efuse->device_info, &record_offset);

if (rtl8xxxu_debug & RTL8XXXU_DEBUG_EFUSE) {
unsigned char *raw = priv->efuse_wifi.raw;
--
2.30.2