realtek: return correct error value for phy ops

A behavioural change was introduced with commit 758c88b96963 ("realtek:
Whitespace and codestyle cleanup") causing rtl838x_read_phy() and
rtl838x_write_phy() to unconditionally return -ETIMEDOUT. As a result,
probing the device during boot fails:

    Error setting up netdev, freeing it again.
    rtl838x-eth: probe of 1b00a300.ethernet failed with error -5

Fix the bootloop caused by this regression with kernel 5.15 on rtl838x
devices, by properly returning 0 on success.

Tested on a Netgear GS108T v3, a Netgear GS310TP v1, a Zyxel GS1900-8HP
v1 and an HPE 1920-8G.

Fixes: 758c88b969639d0e6b684669d2e54dd1be3102f4 ("realtek: Whitespace and codestyle cleanup")
Tested-by: Stijn Segers <foss@volatilesystems.org>
Tested-by: Jan Hoffmann <jan@3e8.eu>
Signed-off-by: Pascal Ernster <git@hardfalcon.net>

diff --git a/target/linux/realtek/files-5.15/drivers/net/dsa/rtl83xx/rtl838x.c b/target/linux/realtek/files-5.15/drivers/net/dsa/rtl83xx/rtl838x.c
index c1d6b0c554bc79488bb7ecc58ade545c1e21c561..cbd4543db4c7954ca5f5bdd283c61c8c5ea5595f 100644 (file)
--- a/target/linux/realtek/files-5.15/drivers/net/dsa/rtl83xx/rtl838x.c
+++ b/target/linux/realtek/files-5.15/drivers/net/dsa/rtl83xx/rtl838x.c
@@ -1832,7 +1832,7 @@ int rtl838x_read_phy(u32 port, u32 page, u32 reg, u32 *val)
 timeout:
        mutex_unlock(&smi_lock);
 
-       return -ETIMEDOUT;
+       return err;
 }
 
 /* Write to a register in a page of the PHY */
@@ -1868,7 +1868,7 @@ int rtl838x_write_phy(u32 port, u32 page, u32 reg, u32 val)
 timeout:
        mutex_unlock(&smi_lock);
 
-       return -ETIMEDOUT;
+       return err;
 }
 
 /* Read an mmd register of a PHY */